IgA Vasculitis

Autoimmune MONDO:0019167 Pathograph 14 Autoimmune Disease Vasculitis

IgA vasculitis (IgAV; formerly Henoch-Schönlein purpura) is the most common systemic vasculitis in childhood, characterized by palpable purpura, arthritis, abdominal pain, and variable renal involvement. Its core immune mechanism -- galactose-deficient IgA1 (Gd-IgA1) overproduction, anti-Gd-IgA1 autoantibody binding, and IgA-containing immune complex deposition in small vessel walls -- is shared with IgA nephropathy (IgAN), but IgAV extends to dermal, gastrointestinal, and synovial microvasculature in addition to the renal mesangium. IgAV predominantly affects children and often follows infectious triggers; adult IgAV carries greater risk of persistent nephritis and chronic kidney disease.

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1
Mappings
0
Definitions
0
Inheritance
5
Pathophysiology
1
Histopathology
5
Phenotypes
14
Pathograph
1
Genes
5
Treatments
2
Subtypes
1
Differentials
0
Datasets
1
Trials
0
Models
6
References
1
Deep Research
🏷

Classifications

Harrison's Chapter
autoimmune disease vascular disease kidney disorder
🔗

Mappings

MONDO
MONDO:0019167 immunoglobulin A vasculitis
skos:exactMatch MONDO
Current MONDO term for IgA vasculitis (formerly Henoch-Schönlein purpura), the systemic small-vessel vasculitis sharing the Gd-IgA1 immune complex mechanism with IgA nephropathy but extending to dermal, gastrointestinal, and synovial microvasculature.
◆

Subtypes

2
IgAV without nephritis
IgAV limited to skin, joints, and/or gastrointestinal involvement without significant renal disease. Predominant presentation in young children; often self-limited.
IgAV with nephritis (IgAVN)
IgAV with concurrent mesangial IgA deposition and glomerulonephritis. Renal involvement ranges from microscopic hematuria to nephrotic-range proteinuria. Persistent nephritis in adults may progress to chronic kidney disease.
⚙

Pathophysiology

5
Gd-IgA1 Overproduction
Galactose-deficient IgA1 (Gd-IgA1) is overproduced by mucosal B cells and plasma cells in IgAV. This upstream abnormal IgA1 glycosylation mechanism is shared with IgA nephropathy and supplies the substrate for pathogenic immune complex formation.
B cell link plasma cell link
humoral immune response link ↑ INCREASED
intestinal mucosa link
Downstream
Anti-Gd-IgA1 Autoantibody Production and Immune Complex Assembly Galactose-deficient IgA1 provides the antigenic substrate for anti-glycan antibody binding and soluble immune complex assembly.
Show evidence (2 references)
PMID:40069065 SUPPORT Human Clinical
"Key molecules involved at each step in both diseases were evaluated as diagnostic and prognostic biomarkers with many common factors, most prominently serum galactose-deficient IgA1."
Confirms that Gd-IgA1 is the central shared upstream molecular mediator in IgAV pathogenesis.
PMID:39497734 SUPPORT Human Clinical
"Galactose-deficient IgA1 on the immunoglobulin hinge region and its immune complexes are thought to play a central pathogenetic role in IgAV"
Directly implicates Gd-IgA1 as the central upstream pathogenic driver in IgAV.
Anti-Gd-IgA1 Autoantibody Production and Immune Complex Assembly
Anti-glycan IgG and IgA autoantibodies recognize exposed N-acetylgalactosamine residues on Gd-IgA1 hinge-region glycans. Binding of these autoantibodies to Gd-IgA1 forms pathogenic soluble immune complexes.
B cell link plasma cell link
immune complex formation link ↑ INCREASED humoral immune response link ↑ INCREASED
Downstream
Systemic IgA Immune Complex Deposition in Small Vessels Circulating Gd-IgA1 immune complexes are deposited in small vessel walls throughout the body.
Show evidence (1 reference)
PMID:34858429 SUPPORT Human Clinical
"Galactose-deficient IgA1 is detected in the tissues of the kidney and skin in patients with IgAV; it forms immune complexes leading to subsequent immune reactions and injuries."
Supports the upstream Gd-IgA1 immune complex mechanism and links it to tissue-level immune injury in skin and kidney.
Systemic IgA Immune Complex Deposition in Small Vessels
IgA-containing immune complexes deposit in the walls of small vessels throughout the body -- including dermal capillaries and postcapillary venules, intestinal submucosal vessels, synovial microvasculature, and renal mesangial cells. Immune complex deposition triggers local complement activation and Fc receptor-mediated neutrophil recruitment, leading to vessel wall injury.
endothelial cell link neutrophil link
complement activation link ↑ INCREASED neutrophil activation link ↑ INCREASED
dermis link intestinal mucosa link
Downstream
Leukocytoclastic Vasculitis in Skin and Systemic Organs Complement-driven neutrophil infiltration of dermal, GI, and synovial small vessels causes leukocytoclastic vasculitis.
IgA Vasculitis Nephritis Mesangial immune complex deposition triggers complement activation and glomerulonephritis indistinguishable from IgAN.
Show evidence (2 references)
PMID:38828518 SUPPORT Human Clinical
"Disease mechanisms involve various factors, including the interplay of aberrantly glycosylated IgA, anti-endothelial cell antibodies, and neutrophils following infection triggers, which are the main pathogenic mechanisms of IgAV."
Confirms that Gd-IgA1 immune complexes, anti-endothelial antibodies, and neutrophil activation are the core pathogenic triad in systemic small-vessel involvement of IgAV.
PMID:34858429 SUPPORT Human Clinical
"Immunoglobin A (IgA) vasculitis (IgAV), formerly called the Henoch-Schönlein purpura (HSP), is a small vessel vasculitis, characterized by IgA1-dominant immune deposition at diseased vessel walls."
Supports the disease-defining small-vessel IgA1 deposition represented by this pathophysiology node.
Leukocytoclastic Vasculitis in Skin and Systemic Organs
Complement activation and neutrophil recruitment to immune complex deposits in small vessel walls results in leukocytoclastic vasculitis: neutrophil extravasation, degranulation, nuclear fragmentation (karyorrhexis), and fibrinoid necrosis. In the skin, this produces palpable purpura predominantly over the lower extremities. In the gastrointestinal tract, submucosal vasculitis causes bowel wall edema, mucosal hemorrhage, and abdominal pain. Synovial vasculitis causes joint pain and swelling.
neutrophil link
complement activation link ↑ INCREASED neutrophil activation link ↑ INCREASED
dermis link intestinal mucosa link synovial membrane link
Show evidence (2 references)
PMID:39497734 SUPPORT Human Clinical
"The primary organs involved are the skin, gastrointestinal (GI) tract, joints, and kidneys."
Confirms the multi-organ distribution of vasculitic injury in IgAV, encompassing the skin, gut, joints, and kidneys as primary affected sites.
PMID:38828518 SUPPORT Human Clinical
"Palpable purpura, gastrointestinal symptoms, joint involvement, and renal disease characterize immunoglobulin A vasculitis (IgAV)."
Summarizes the systemic organ manifestations downstream of leukocytoclastic vasculitis in IgAV.
IgA Vasculitis Nephritis
When IgA immune complexes deposit in the renal mesangium, the resulting glomerulonephritis (IgAVN) is histologically identical to IgA nephropathy. Mesangial IgA deposits activate complement and mesangial cells, causing hematuria, proteinuria, and in severe cases, rapidly progressive glomerulonephritis with crescents. Adult-onset IgAVN has higher risk of progression to chronic kidney disease than childhood IgAVN.
mesangial cell link podocyte link endothelial cell link
complement activation, lectin pathway link ↑ INCREASED
Show evidence (2 references)
PMID:40069065 SUPPORT Human Clinical
"On kidney biopsy, the two diseases are indistinguishable, and the established histological Oxford classification for IgAN will soon be validated for IgAVN."
Confirms that IgAVN produces histologically identical renal lesions to IgAN, reflecting the same immune complex-mediated mesangial injury mechanism.
PMID:38828518 SUPPORT Human Clinical
"Renal involvement ranging from mild proteinuria to severe nephritic or nephrotic syndrome highlights the importance of monitoring kidney function in patients with IgAV."
Confirms the clinical spectrum of IgAVN from mild microscopic hematuria to severe nephrotic syndrome, consistent with complement-driven mesangial injury.
✶

Histopathology

1
Leukocytoclastic Vasculitis with IgA Deposits
IgAV tissue pathology is defined by IgA-dominant immune deposition in affected small vessels and renal lesions that overlap with IgA nephropathy. GI mucosal biopsy may show diagnostic IgA deposition, and renal biopsy shows IgAVN lesions indistinguishable from IgAN with relatively frequent proliferative lesions such as endocapillary hypercellularity and crescents.
Show evidence (3 references)
PMID:32803924 SUPPORT Human Clinical
"Henoch-Schönlein purpura, now called immunoglobulin A (IgA) vasculitis, is a systemic, immune complex-mediated, small-vessel leukocytoclastic vasculitis characterized by nonthrombocytopenic palpable purpura, arthritis, and abdominal pain."
Supports the leukocytoclastic small-vessel vasculitis framing for IgAV tissue pathology.
PMID:39497734 SUPPORT Human Clinical
"The GI mucosal involvement when evaluated microscopically shows IgA deposition which is histologically diagnostic."
Confirms that IgA deposition on mucosal biopsy is histologically diagnostic for GI involvement in IgAV.
PMID:40069065 SUPPORT Human Clinical
"On kidney biopsy, the two diseases are indistinguishable, and the established histological Oxford classification for IgAN will soon be validated for IgAVN."
Supports the renal histopathology claim that IgAVN biopsy lesions overlap with IgA nephropathy.
⬡

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.
Pathograph: causal mechanism network for IgA Vasculitis Interactive directed graph showing how pathophysiology mechanisms, phenotypes, genetic factors and variants, experimental models, environmental triggers, and treatments relate through causal and linked edges.
●

Phenotypes

5
Genitourinary 2
Hematuria Hematuria (HP:0000790)
Show evidence (2 references)
PMID:38828518 SUPPORT Human Clinical
"Renal involvement ranging from mild proteinuria to severe nephritic or nephrotic syndrome highlights the importance of monitoring kidney function in patients with IgAV."
Supports hematuria as part of the renal involvement spectrum in IgAV.
PMID:34858429 SUPPORT Human Clinical
"typical symptoms include palpable purpura, arthritis or arthralgia, abdominal pain, and hematuria or proteinuria."
Directly supports hematuria as a typical renal manifestation of IgAV.
Proteinuria Proteinuria (HP:0000093)
Show evidence (2 references)
PMID:38828518 SUPPORT Human Clinical
"Renal involvement ranging from mild proteinuria to severe nephritic or nephrotic syndrome highlights the importance of monitoring kidney function in patients with IgAV."
Directly supports proteinuria as a core renal phenotype in IgAV nephritis.
PMID:34858429 SUPPORT Human Clinical
"typical symptoms include palpable purpura, arthritis or arthralgia, abdominal pain, and hematuria or proteinuria."
Directly supports proteinuria as a typical renal manifestation of IgAV.
Musculoskeletal 1
Arthritis Arthritis (HP:0001369)
Show evidence (2 references)
PMID:38828518 SUPPORT Human Clinical
"Palpable purpura, gastrointestinal symptoms, joint involvement, and renal disease characterize immunoglobulin A vasculitis (IgAV)."
Confirms joint involvement as a characteristic clinical feature of IgAV.
PMID:34858429 SUPPORT Human Clinical
"typical symptoms include palpable purpura, arthritis or arthralgia, abdominal pain, and hematuria or proteinuria."
Directly supports arthritis or arthralgia as a typical IgAV symptom.
Constitutional 1
Abdominal Pain Abdominal pain (HP:0002027)
Show evidence (2 references)
PMID:39497734 SUPPORT Human Clinical
"The primary organs involved are the skin, gastrointestinal (GI) tract, joints, and kidneys."
Confirms gastrointestinal involvement as a primary organ manifestation in IgAV, supporting abdominal pain as a core phenotype.
PMID:34858429 SUPPORT Human Clinical
"typical symptoms include palpable purpura, arthritis or arthralgia, abdominal pain, and hematuria or proteinuria."
Directly supports abdominal pain as a typical IgAV symptom.
Other 1
Palpable Purpura Palpable purpura (HP:0031363)
Show evidence (2 references)
PMID:38828518 SUPPORT Human Clinical
"Palpable purpura, gastrointestinal symptoms, joint involvement, and renal disease characterize immunoglobulin A vasculitis (IgAV)."
Identifies palpable purpura as the defining clinical feature of IgAV.
PMID:34858429 SUPPORT Human Clinical
"typical symptoms include palpable purpura, arthritis or arthralgia, abdominal pain, and hematuria or proteinuria."
Identifies palpable purpura among the typical IgAV clinical symptoms.
🧬

Genetic Associations

1
Shared IgAN-IgAV Genetic Susceptibility (Shared common-variant susceptibility architecture)
Show evidence (1 reference)
PMID:40069065 SUPPORT Human Clinical
"The two diseases share similar geographic and ethnic distribution, along with common variants in genetic association studies."
Supports shared polygenic susceptibility architecture across IgAV and IgAN without implying a single Mendelian cause.
💊

Treatments

5
Supportive Care
Action: supportive care MAXO:0000950
For uncomplicated IgAV without nephritis or severe GI involvement, management is supportive. Analgesics address arthritic pain. Most IgAV resolves without immunosuppressive therapy.
Target Phenotypes: Arthritis ↗ Abdominal pain ↗
Show evidence (2 references)
PMID:40975525 PARTIAL Other
"Little has changed for special situations of IgA-dominant immune complex glomerular diseases such as nephrotic syndrome, acute kidney injury, rapidly progressive glomerulonephritis, and pregnancy in IgAN, or children with IgAN or IgAV, given the lack of major clinical trials in these patient populations."
KDIGO 2025 acknowledges limited evidence for IgAV treatment due to a lack of major clinical trials; conservative/supportive management for uncomplicated IgAV is by default the standard approach.
PMID:32803924 SUPPORT Human Clinical
"IgA vasculitis spontaneously resolves in 94% of children and 89% of adults, making supportive treatment the primary management strategy."
Directly supports supportive care as the primary management strategy for most IgAV presentations.
Corticosteroids for Severe GI Vasculitis or Nephritis
Action: pharmacotherapy MAXO:0000058
Agent: prednisolone ↗
Oral prednisolone is used for severe or refractory gastrointestinal vasculitis or for IgAV nephritis with significant proteinuria. Corticosteroids are often first-line for IgAVN with moderate-to-severe proteinuria, following protocols extrapolated from IgAN given limited IgAV-specific trial data.
Mechanism Target:
Gd-IgA1 Overproduction — Corticosteroids broadly suppress B-cell and plasma-cell activity, reducing pathogenic IgA production upstream of immune complex formation.
Target Phenotypes: Abdominal pain ↗ Proteinuria ↗
Show evidence (1 reference)
PMID:40975525 PARTIAL Other
"A major new concept in the 2025 guideline is to initiate treatment with (i) therapies that prevent or reduce pathogenic IgA production and IgA/IgA and IgA/IgG immune complex formation along with (ii) therapies to manage the consequences of existing IgAN-induced nephron loss."
KDIGO 2025 supports targeting IgA production and immune complex formation as the primary therapeutic goal; corticosteroids fulfill this principle for IgAVN, though the guideline is IgAN-primary and only partially applies to IgAV.
Targeted-Release Budesonide (Nefecon)
Action: pharmacotherapy MAXO:0000058
Agent: budesonide ↗
Targeted-release budesonide is used in IgAN to reduce pathogenic mucosal IgA production. KDIGO 2025 includes targeted-release budesonide as an approach within the IgAN/IgAV guideline scope, but IgAV-specific trial evidence remains limited, so this is modeled as partial support for IgAVN.
Mechanism Target:
Gd-IgA1 Overproduction — Targeted-release budesonide is intended to reduce pathogenic mucosal IgA production upstream of immune-complex deposition.
Target Phenotypes: Proteinuria ↗
Show evidence (1 reference)
PMID:40975525 PARTIAL Other
"Approaches to achieve the first aim are currently limited to targeted-release budesonide (Nefecon) or reduced-dose systemic corticosteroid therapy and, in Chinese patients, mycophenolate mofetil."
KDIGO 2025 names targeted-release budesonide as a therapy to reduce pathogenic IgA production in the IgAN/IgAV guideline scope; the evidence is IgAN-primary and therefore only partially applicable to IgAV.
Immunosuppressive Therapy for Crescentic IgAVN
Action: pharmacotherapy MAXO:0000058
Agent: cyclophosphamide ↗ mycophenolate mofetil ↗
Severe IgAV nephritis with crescents or rapidly progressive glomerulonephritis is managed analogously to crescentic IgAN, typically with corticosteroids combined with cyclophosphamide or mycophenolate mofetil. These regimens are extrapolated from IgAN given the lack of large IgAV-specific randomized controlled trials.
Mechanism Target:
Anti-Gd-IgA1 Autoantibody Production and Immune Complex Assembly — Cyclophosphamide and mycophenolate mofetil broadly suppress antibody responses, reducing the pathogenic immune-complex load.
Target Phenotypes: Proteinuria ↗
Show evidence (1 reference)
PMID:40975525 PARTIAL Other
"Little has changed for special situations of IgA-dominant immune complex glomerular diseases such as nephrotic syndrome, acute kidney injury, rapidly progressive glomerulonephritis, and pregnancy in IgAN, or children with IgAN or IgAV, given the lack of major clinical trials in these patient populations."
KDIGO 2025 acknowledges a lack of major randomized trials specifically in IgAV; immunosuppressive regimens for severe IgAVN are extrapolated from IgAN evidence.
Rituximab for Adult Relapsing or Severe IgAV
Action: pharmacotherapy MAXO:0000058
Agent: rituximab ↗
Rituximab is a B-cell-depleting anti-CD20 monoclonal antibody under prospective Phase III evaluation with glucocorticoids for newly diagnosed or relapsing adult IgAV. Existing support is partial because the trial is active and results are not yet available.
Mechanism Target:
Anti-Gd-IgA1 Autoantibody Production and Immune Complex Assembly — B-cell depletion may reduce pathogenic anti-Gd-IgA1 antibody responses and downstream immune-complex formation.
Target Phenotypes: Palpable purpura ↗ Abdominal pain ↗ Proteinuria ↗
Show evidence (1 reference)
clinicaltrials:NCT05329090 PARTIAL Human Clinical
"Recently, a multicenter observational study suggested that RTX was an effective and safe therapeutic option for treating relapsed and / or refractory adult IgAV."
Supports rituximab as a plausible IgAV therapy under prospective trial evaluation, while results remain pending.
🔀

Differential Diagnoses

1

Conditions with similar clinical presentations that must be differentiated from IgA Vasculitis:

IgA Nephropathy MONDO:0005342
Overlapping Features IgAN and IgAVN share identical Gd-IgA1 pathomechanism and indistinguishable renal biopsy findings. The key distinguishing feature is the presence of systemic vasculitic manifestations in IgAV (palpable purpura, arthritis, GI vasculitis) that are absent in kidney-limited IgAN.
Distinguishing Features
  • Palpable purpura and extra-renal vasculitic features are present in IgAV but absent in IgAN.
  • Kidney biopsy alone cannot distinguish IgAVN from IgAN; clinical context is essential.
  • Younger age and post-infectious trigger favor IgAV; adult onset without systemic features favors IgAN.
  • IgAVN tends to have more proliferative lesions while IgAN accumulates more chronic sclerosing lesions.
Show evidence (1 reference)
PMID:40069065 SUPPORT Human Clinical
"IgA vasculitis (IgAV) is considered a systemic form of IgA nephropathy (IgAN). The two diseases share similar geographic and ethnic distribution, along with common variants in genetic association studies."
Establishes mechanistic kinship between IgAV and IgAN while supporting the split decision: IgAV systemic vasculitic manifestations warrant separate disease representation from kidney-limited IgAN.
🔬

Clinical Trials

1
NCT05329090 PHASE_III ACTIVE_NOT_RECRUITING
RIGA is a prospective, randomized, controlled, double-blind Phase III trial evaluating glucocorticoids plus rituximab versus glucocorticoids plus placebo for induction of remission in adults with newly diagnosed or relapsing IgA vasculitis.
Target Phenotypes: Palpable purpura ↗ Abdominal pain ↗ Proteinuria ↗
Show evidence (1 reference)
clinicaltrials:NCT05329090 SUPPORT Human Clinical
"Overall, RTX may be an effective and safe therapeutic approach in adult IgAVs, justifying the need for a prospective randomized controlled trial evaluating Rituximab as an induction of remission for adult IgAV."
ClinicalTrials.gov documents an IgAV-specific randomized rituximab trial for induction of remission in adult IgAV.
{ }

Source YAML

click to show 
name: IgA Vasculitis
creation_date: "2026-04-22T00:00:00Z"
updated_date: "2026-04-29T00:10:20Z"
category: Autoimmune
parents:
- Autoimmune Disease
- Vasculitis
disease_term:
  preferred_term: IgA vasculitis
  term:
    id: MONDO:0019167
    label: immunoglobulin A vasculitis
synonyms:
- Henoch-Schönlein purpura
- Henoch-Schönlein disease
- purpura rheumatica
- anaphylactoid purpura
- Schönlein-Henoch purpura
mappings:
  mondo_mappings:
  - term:
      id: MONDO:0019167
      label: immunoglobulin A vasculitis
    mapping_predicate: skos:exactMatch
    mapping_source: MONDO
    mapping_justification: >-
      Current MONDO term for IgA vasculitis (formerly Henoch-Schönlein purpura),
      the systemic small-vessel vasculitis sharing the Gd-IgA1 immune complex
      mechanism with IgA nephropathy but extending to dermal, gastrointestinal,
      and synovial microvasculature.
description: >-
  IgA vasculitis (IgAV; formerly Henoch-Schönlein purpura) is the most common
  systemic vasculitis in childhood, characterized by palpable purpura, arthritis,
  abdominal pain, and variable renal involvement. Its core immune mechanism --
  galactose-deficient IgA1 (Gd-IgA1) overproduction, anti-Gd-IgA1 autoantibody
  binding, and IgA-containing immune complex deposition in small vessel walls --
  is shared with IgA nephropathy
  (IgAN), but IgAV extends to dermal, gastrointestinal, and synovial
  microvasculature in addition to the renal mesangium. IgAV predominantly
  affects children and often follows infectious triggers; adult
  IgAV carries greater risk of persistent nephritis and chronic kidney disease.
notes: >-
  Lump/split decision (issue #1326): IgAV and IgAN share the identical
  Gd-IgA1 -> anti-Gd-IgA1 autoantibody -> immune complex -> mesangial injury
  mechanism, and IgAV nephritis (IgAVN) is histologically indistinguishable
  from IgAN on renal biopsy. However, the systemic small-vessel vasculitis
  manifestations of IgAV -- palpable purpura, GI vasculitis, and arthritis --
  cannot be captured within the kidney-limited IgAN entry. Separate entries
  are maintained (SPLIT decision), with the shared renal mechanism detailed
  in kb/disorders/IgA_Nephropathy.yaml. Cross-references are bidirectional.
has_subtypes:
- name: IgAV without nephritis
  display_name: IgAV without nephritis
  description: >-
    IgAV limited to skin, joints, and/or gastrointestinal involvement without
    significant renal disease. Predominant presentation in young children;
    often self-limited.
- name: IgAV with nephritis
  display_name: IgAV with nephritis (IgAVN)
  description: >-
    IgAV with concurrent mesangial IgA deposition and glomerulonephritis.
    Renal involvement ranges from microscopic hematuria to nephrotic-range
    proteinuria. Persistent nephritis in adults may progress to chronic kidney
    disease.
pathophysiology:
- name: Gd-IgA1 Overproduction
  description: >-
    Galactose-deficient IgA1 (Gd-IgA1) is overproduced by mucosal B cells and
    plasma cells in IgAV. This upstream abnormal IgA1 glycosylation mechanism
    is shared with IgA nephropathy and supplies the substrate for pathogenic
    immune complex formation.
  cell_types:
  - preferred_term: B cell
    term:
      id: CL:0000236
      label: B cell
  - preferred_term: plasma cell
    term:
      id: CL:0000786
      label: plasma cell
  locations:
  - preferred_term: intestinal mucosa
    term:
      id: UBERON:0001242
      label: intestinal mucosa
  biological_processes:
  - preferred_term: humoral immune response
    term:
      id: GO:0006959
      label: humoral immune response
    modifier: INCREASED
  downstream:
  - target: Anti-Gd-IgA1 Autoantibody Production and Immune Complex Assembly
    description: >-
      Galactose-deficient IgA1 provides the antigenic substrate for anti-glycan
      antibody binding and soluble immune complex assembly.
  evidence:
  - reference: PMID:40069065
    reference_title: "IgA Vasculitis and IgA Nephropathy: Two Sides of the Same Coin?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Key molecules involved at each step in both diseases were evaluated as
      diagnostic and prognostic biomarkers with many common factors, most
      prominently serum galactose-deficient IgA1.
    explanation: >-
      Confirms that Gd-IgA1 is the central shared upstream molecular mediator
      in IgAV pathogenesis.
  - reference: PMID:39497734
    reference_title: "Gastrointestinal manifestations and pathogenesis in childhood immunoglobulin A vasculitis."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Galactose-deficient IgA1 on the immunoglobulin hinge region and its immune
      complexes are thought to play a central pathogenetic role in IgAV
    explanation: >-
      Directly implicates Gd-IgA1 as the central upstream pathogenic driver in
      IgAV.

- name: Anti-Gd-IgA1 Autoantibody Production and Immune Complex Assembly
  description: >-
    Anti-glycan IgG and IgA autoantibodies recognize exposed
    N-acetylgalactosamine residues on Gd-IgA1 hinge-region glycans. Binding of
    these autoantibodies to Gd-IgA1 forms pathogenic soluble immune complexes.
  cell_types:
  - preferred_term: B cell
    term:
      id: CL:0000236
      label: B cell
  - preferred_term: plasma cell
    term:
      id: CL:0000786
      label: plasma cell
  biological_processes:
  - preferred_term: immune complex formation
    term:
      id: GO:0097281
      label: immune complex formation
    modifier: INCREASED
  - preferred_term: humoral immune response
    term:
      id: GO:0006959
      label: humoral immune response
    modifier: INCREASED
  downstream:
  - target: Systemic IgA Immune Complex Deposition in Small Vessels
    description: >-
      Circulating Gd-IgA1 immune complexes are deposited in small vessel walls
      throughout the body.
  evidence:
  - reference: PMID:34858429
    reference_title: "Pathogenesis of IgA Vasculitis: An Up-To-Date Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Galactose-deficient IgA1 is detected in the tissues of the kidney and skin
      in patients with IgAV; it forms immune complexes leading to subsequent
      immune reactions and injuries.
    explanation: >-
      Supports the upstream Gd-IgA1 immune complex mechanism and links it to
      tissue-level immune injury in skin and kidney.

- name: Systemic IgA Immune Complex Deposition in Small Vessels
  description: >-
    IgA-containing immune complexes deposit in the walls of small vessels
    throughout the body -- including dermal capillaries and postcapillary venules,
    intestinal submucosal vessels, synovial microvasculature, and renal mesangial
    cells. Immune complex deposition triggers local complement activation and
    Fc receptor-mediated neutrophil recruitment, leading to vessel wall injury.
  cell_types:
  - preferred_term: endothelial cell
    term:
      id: CL:0000115
      label: endothelial cell
  - preferred_term: neutrophil
    term:
      id: CL:0000775
      label: neutrophil
  locations:
  - preferred_term: dermis
    term:
      id: UBERON:0002067
      label: dermis
  - preferred_term: intestinal mucosa
    term:
      id: UBERON:0001242
      label: intestinal mucosa
  biological_processes:
  - preferred_term: complement activation
    term:
      id: GO:0006956
      label: complement activation
    modifier: INCREASED
  - preferred_term: neutrophil activation
    term:
      id: GO:0042119
      label: neutrophil activation
    modifier: INCREASED
  downstream:
  - target: Leukocytoclastic Vasculitis in Skin and Systemic Organs
    description: >-
      Complement-driven neutrophil infiltration of dermal, GI, and synovial
      small vessels causes leukocytoclastic vasculitis.
  - target: IgA Vasculitis Nephritis
    description: >-
      Mesangial immune complex deposition triggers complement activation and
      glomerulonephritis indistinguishable from IgAN.
  evidence:
  - reference: PMID:38828518
    reference_title: "Immunoglobulin A vasculitis: The clinical features and pathophysiology."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Disease mechanisms involve various factors, including the interplay of
      aberrantly glycosylated IgA, anti-endothelial cell antibodies, and
      neutrophils following infection triggers, which are the main pathogenic
      mechanisms of IgAV.
    explanation: >-
      Confirms that Gd-IgA1 immune complexes, anti-endothelial antibodies, and
      neutrophil activation are the core pathogenic triad in systemic
      small-vessel involvement of IgAV.
  - reference: PMID:34858429
    reference_title: "Pathogenesis of IgA Vasculitis: An Up-To-Date Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Immunoglobin A (IgA) vasculitis (IgAV), formerly called the Henoch-Schönlein
      purpura (HSP), is a small vessel vasculitis, characterized by IgA1-dominant
      immune deposition at diseased vessel walls.
    explanation: >-
      Supports the disease-defining small-vessel IgA1 deposition represented by
      this pathophysiology node.

- name: Leukocytoclastic Vasculitis in Skin and Systemic Organs
  description: >-
    Complement activation and neutrophil recruitment to immune complex deposits
    in small vessel walls results in leukocytoclastic vasculitis: neutrophil
    extravasation, degranulation, nuclear fragmentation (karyorrhexis), and
    fibrinoid necrosis. In the skin, this produces palpable purpura predominantly
    over the lower extremities. In the gastrointestinal tract, submucosal
    vasculitis causes bowel wall edema, mucosal hemorrhage, and abdominal pain.
    Synovial vasculitis causes joint pain and swelling.
  cell_types:
  - preferred_term: neutrophil
    term:
      id: CL:0000775
      label: neutrophil
  locations:
  - preferred_term: dermis
    term:
      id: UBERON:0002067
      label: dermis
  - preferred_term: intestinal mucosa
    term:
      id: UBERON:0001242
      label: intestinal mucosa
  - preferred_term: synovial membrane
    term:
      id: UBERON:0002018
      label: synovial membrane of synovial joint
  biological_processes:
  - preferred_term: complement activation
    term:
      id: GO:0006956
      label: complement activation
    modifier: INCREASED
  - preferred_term: neutrophil activation
    term:
      id: GO:0042119
      label: neutrophil activation
    modifier: INCREASED
  evidence:
  - reference: PMID:39497734
    reference_title: "Gastrointestinal manifestations and pathogenesis in childhood immunoglobulin A vasculitis."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The primary organs involved are the skin, gastrointestinal (GI) tract,
      joints, and kidneys.
    explanation: >-
      Confirms the multi-organ distribution of vasculitic injury in IgAV,
      encompassing the skin, gut, joints, and kidneys as primary affected sites.
  - reference: PMID:38828518
    reference_title: "Immunoglobulin A vasculitis: The clinical features and pathophysiology."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Palpable purpura, gastrointestinal symptoms, joint involvement, and renal
      disease characterize immunoglobulin A vasculitis (IgAV).
    explanation: >-
      Summarizes the systemic organ manifestations downstream of leukocytoclastic
      vasculitis in IgAV.

- name: IgA Vasculitis Nephritis
  description: >-
    When IgA immune complexes deposit in the renal mesangium, the resulting
    glomerulonephritis (IgAVN) is histologically identical to IgA nephropathy.
    Mesangial IgA deposits activate complement and mesangial cells, causing
    hematuria, proteinuria, and in severe cases, rapidly progressive
    glomerulonephritis with crescents. Adult-onset IgAVN has higher risk of
    progression to chronic kidney disease than childhood IgAVN.
  cell_types:
  - preferred_term: mesangial cell
    term:
      id: CL:0000650
      label: mesangial cell
  - preferred_term: podocyte
    term:
      id: CL:0000653
      label: podocyte
  - preferred_term: endothelial cell
    term:
      id: CL:0000115
      label: endothelial cell
  biological_processes:
  - preferred_term: complement activation, lectin pathway
    term:
      id: GO:0001867
      label: complement activation, lectin pathway
    modifier: INCREASED
  evidence:
  - reference: PMID:40069065
    reference_title: "IgA Vasculitis and IgA Nephropathy: Two Sides of the Same Coin?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      On kidney biopsy, the two diseases are indistinguishable, and the
      established histological Oxford classification for IgAN will soon be
      validated for IgAVN.
    explanation: >-
      Confirms that IgAVN produces histologically identical renal lesions to
      IgAN, reflecting the same immune complex-mediated mesangial injury
      mechanism.
  - reference: PMID:38828518
    reference_title: "Immunoglobulin A vasculitis: The clinical features and pathophysiology."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Renal involvement ranging from mild proteinuria to severe nephritic or
      nephrotic syndrome highlights the importance of monitoring kidney function
      in patients with IgAV.
    explanation: >-
      Confirms the clinical spectrum of IgAVN from mild microscopic hematuria
      to severe nephrotic syndrome, consistent with complement-driven mesangial
      injury.

phenotypes:
- category: Dermatologic
  name: Palpable Purpura
  description: >-
    Non-thrombocytopenic palpable purpura over the lower extremities and buttocks
    is the hallmark cutaneous manifestation of IgAV. It results from IgA immune
    complex deposition in dermal capillaries and leukocytoclastic vasculitis.
    Purpura is the defining clinical feature for IgAV diagnosis.
  phenotype_term:
    preferred_term: Palpable purpura
    term:
      id: HP:0031363
      label: Palpable purpura
  evidence:
  - reference: PMID:38828518
    reference_title: "Immunoglobulin A vasculitis: The clinical features and pathophysiology."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Palpable purpura, gastrointestinal symptoms, joint involvement, and renal
      disease characterize immunoglobulin A vasculitis (IgAV).
    explanation: >-
      Identifies palpable purpura as the defining clinical feature of IgAV.
  - reference: PMID:34858429
    reference_title: "Pathogenesis of IgA Vasculitis: An Up-To-Date Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      typical symptoms include palpable purpura, arthritis or arthralgia,
      abdominal pain, and hematuria or proteinuria.
    explanation: >-
      Identifies palpable purpura among the typical IgAV clinical symptoms.

- category: Musculoskeletal
  name: Arthritis
  description: >-
    Arthritis or arthralgia is a typical musculoskeletal manifestation of IgAV.
    Joint involvement results from IgA immune complex deposition and
    leukocytoclastic vasculitis in synovial microvasculature, and is typically
    non-destructive and transient.
  phenotype_term:
    preferred_term: Arthritis
    term:
      id: HP:0001369
      label: Arthritis
  evidence:
  - reference: PMID:38828518
    reference_title: "Immunoglobulin A vasculitis: The clinical features and pathophysiology."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Palpable purpura, gastrointestinal symptoms, joint involvement, and renal
      disease characterize immunoglobulin A vasculitis (IgAV).
    explanation: >-
      Confirms joint involvement as a characteristic clinical feature of IgAV.
  - reference: PMID:34858429
    reference_title: "Pathogenesis of IgA Vasculitis: An Up-To-Date Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      typical symptoms include palpable purpura, arthritis or arthralgia,
      abdominal pain, and hematuria or proteinuria.
    explanation: >-
      Directly supports arthritis or arthralgia as a typical IgAV symptom.

- category: Gastrointestinal
  name: Abdominal Pain
  description: >-
    Colicky abdominal pain is a typical gastrointestinal manifestation of IgAV,
    resulting from IgA immune complex deposition in intestinal submucosal
    vessels causing bowel wall edema and hemorrhage. More severe GI involvement
    includes hematochezia, intussusception, or bowel perforation.
  phenotype_term:
    preferred_term: Abdominal pain
    term:
      id: HP:0002027
      label: Abdominal pain
  evidence:
  - reference: PMID:39497734
    reference_title: "Gastrointestinal manifestations and pathogenesis in childhood immunoglobulin A vasculitis."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The primary organs involved are the skin, gastrointestinal (GI) tract,
      joints, and kidneys.
    explanation: >-
      Confirms gastrointestinal involvement as a primary organ manifestation
      in IgAV, supporting abdominal pain as a core phenotype.
  - reference: PMID:34858429
    reference_title: "Pathogenesis of IgA Vasculitis: An Up-To-Date Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      typical symptoms include palpable purpura, arthritis or arthralgia,
      abdominal pain, and hematuria or proteinuria.
    explanation: >-
      Directly supports abdominal pain as a typical IgAV symptom.

- category: Renal
  name: Hematuria
  description: >-
    Microscopic or gross hematuria is the most common initial renal manifestation
    in IgAV nephritis, reflecting red blood cell extravasation from
    complement-activated and inflamed glomeruli. IgAVN with isolated hematuria
    carries a favorable prognosis in children.
  subtype: IgAV with nephritis
  phenotype_term:
    preferred_term: Hematuria
    term:
      id: HP:0000790
      label: Hematuria
  evidence:
  - reference: PMID:38828518
    reference_title: "Immunoglobulin A vasculitis: The clinical features and pathophysiology."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Renal involvement ranging from mild proteinuria to severe nephritic or
      nephrotic syndrome highlights the importance of monitoring kidney function
      in patients with IgAV.
    explanation: >-
      Supports hematuria as part of the renal involvement spectrum in IgAV.
  - reference: PMID:34858429
    reference_title: "Pathogenesis of IgA Vasculitis: An Up-To-Date Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      typical symptoms include palpable purpura, arthritis or arthralgia,
      abdominal pain, and hematuria or proteinuria.
    explanation: >-
      Directly supports hematuria as a typical renal manifestation of IgAV.

- category: Renal
  name: Proteinuria
  description: >-
    Proteinuria ranging from subnephrotic to nephrotic-range is a key indicator
    of IgAV nephritis severity. Nephrotic-range proteinuria in IgAVN is
    associated with more severe glomerular lesions (endocapillary
    hypercellularity, crescents) and worse renal outcomes, particularly in adults.
  subtype: IgAV with nephritis
  phenotype_term:
    preferred_term: Proteinuria
    term:
      id: HP:0000093
      label: Proteinuria
  evidence:
  - reference: PMID:38828518
    reference_title: "Immunoglobulin A vasculitis: The clinical features and pathophysiology."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Renal involvement ranging from mild proteinuria to severe nephritic or
      nephrotic syndrome highlights the importance of monitoring kidney function
      in patients with IgAV.
    explanation: >-
      Directly supports proteinuria as a core renal phenotype in IgAV nephritis.
  - reference: PMID:34858429
    reference_title: "Pathogenesis of IgA Vasculitis: An Up-To-Date Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      typical symptoms include palpable purpura, arthritis or arthralgia,
      abdominal pain, and hematuria or proteinuria.
    explanation: >-
      Directly supports proteinuria as a typical renal manifestation of IgAV.

genetic:
- name: Shared IgAN-IgAV Genetic Susceptibility
  association: Shared common-variant susceptibility architecture
  notes: >-
    IgAV is not modeled here as a monogenic disorder. Current clinical reviews
    support shared common-variant genetic susceptibility with IgA nephropathy,
    consistent with their shared Gd-IgA1 immune-complex mechanism.
  evidence:
  - reference: PMID:40069065
    reference_title: "IgA Vasculitis and IgA Nephropathy: Two Sides of the Same Coin?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The two diseases share similar geographic and ethnic distribution, along
      with common variants in genetic association studies.
    explanation: >-
      Supports shared polygenic susceptibility architecture across IgAV and
      IgAN without implying a single Mendelian cause.

treatments:
- name: Supportive Care
  description: >-
    For uncomplicated IgAV without nephritis or severe GI involvement, management
    is supportive. Analgesics address arthritic pain. Most IgAV resolves without
    immunosuppressive therapy.
  treatment_term:
    preferred_term: supportive care
    term:
      id: MAXO:0000950
      label: supportive care
  target_phenotypes:
  - preferred_term: Arthritis
    term:
      id: HP:0001369
      label: Arthritis
  - preferred_term: Abdominal pain
    term:
      id: HP:0002027
      label: Abdominal pain
  evidence:
  - reference: PMID:40975525
    reference_title: "Executive summary of the KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV)."
    supports: PARTIAL
    evidence_source: OTHER
    snippet: >-
      Little has changed for special situations of IgA-dominant immune complex
      glomerular diseases such as nephrotic syndrome, acute kidney injury, rapidly
      progressive glomerulonephritis, and pregnancy in IgAN, or children with
      IgAN or IgAV, given the lack of major clinical trials in these patient
      populations.
    explanation: >-
      KDIGO 2025 acknowledges limited evidence for IgAV treatment due to a lack
      of major clinical trials; conservative/supportive management for
      uncomplicated IgAV is by default the standard approach.
  - reference: PMID:32803924
    reference_title: "Henoch-Schönlein Purpura (IgA Vasculitis): Rapid Evidence Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      IgA vasculitis spontaneously resolves in 94% of children and 89% of adults,
      making supportive treatment the primary management strategy.
    explanation: >-
      Directly supports supportive care as the primary management strategy for
      most IgAV presentations.

- name: Corticosteroids for Severe GI Vasculitis or Nephritis
  description: >-
    Oral prednisolone is used for severe or refractory gastrointestinal
    vasculitis or for IgAV nephritis with significant proteinuria. Corticosteroids
    are often first-line for IgAVN with moderate-to-severe proteinuria, following
    protocols extrapolated from IgAN given limited IgAV-specific trial data.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
    therapeutic_agent:
    - preferred_term: prednisolone
      term:
        id: CHEBI:8378
        label: prednisolone
  target_phenotypes:
  - preferred_term: Abdominal pain
    term:
      id: HP:0002027
      label: Abdominal pain
  - preferred_term: Proteinuria
    term:
      id: HP:0000093
      label: Proteinuria
  target_mechanisms:
  - target: Gd-IgA1 Overproduction
    description: >-
      Corticosteroids broadly suppress B-cell and plasma-cell activity, reducing
      pathogenic IgA production upstream of immune complex formation.
  evidence:
  - reference: PMID:40975525
    reference_title: "Executive summary of the KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV)."
    supports: PARTIAL
    evidence_source: OTHER
    snippet: >-
      A major new concept in the 2025 guideline is to initiate treatment with
      (i) therapies that prevent or reduce pathogenic IgA production and IgA/IgA
      and IgA/IgG immune complex formation along with (ii) therapies to manage
      the consequences of existing IgAN-induced nephron loss.
    explanation: >-
      KDIGO 2025 supports targeting IgA production and immune complex formation
      as the primary therapeutic goal; corticosteroids fulfill this principle for
      IgAVN, though the guideline is IgAN-primary and only partially applies to
      IgAV.

- name: Targeted-Release Budesonide (Nefecon)
  description: >-
    Targeted-release budesonide is used in IgAN to reduce pathogenic mucosal IgA
    production. KDIGO 2025 includes targeted-release budesonide as an approach
    within the IgAN/IgAV guideline scope, but IgAV-specific trial evidence
    remains limited, so this is modeled as partial support for IgAVN.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
    therapeutic_agent:
    - preferred_term: budesonide
      term:
        id: CHEBI:3207
        label: budesonide
  target_phenotypes:
  - preferred_term: Proteinuria
    term:
      id: HP:0000093
      label: Proteinuria
  target_mechanisms:
  - target: Gd-IgA1 Overproduction
    description: >-
      Targeted-release budesonide is intended to reduce pathogenic mucosal IgA
      production upstream of immune-complex deposition.
  evidence:
  - reference: PMID:40975525
    reference_title: "Executive summary of the KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV)."
    supports: PARTIAL
    evidence_source: OTHER
    snippet: >-
      Approaches to achieve the first aim are currently limited to
      targeted-release budesonide (Nefecon) or reduced-dose systemic
      corticosteroid therapy and, in Chinese patients, mycophenolate mofetil.
    explanation: >-
      KDIGO 2025 names targeted-release budesonide as a therapy to reduce
      pathogenic IgA production in the IgAN/IgAV guideline scope; the evidence
      is IgAN-primary and therefore only partially applicable to IgAV.

- name: Immunosuppressive Therapy for Crescentic IgAVN
  description: >-
    Severe IgAV nephritis with crescents or rapidly progressive glomerulonephritis
    is managed analogously to crescentic IgAN, typically with corticosteroids
    combined with cyclophosphamide or mycophenolate mofetil. These regimens are
    extrapolated from IgAN given the lack of large IgAV-specific randomized
    controlled trials.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
    therapeutic_agent:
    - preferred_term: cyclophosphamide
      term:
        id: CHEBI:4027
        label: cyclophosphamide
    - preferred_term: mycophenolate mofetil
      term:
        id: CHEBI:8764
        label: mycophenolate mofetil
  target_phenotypes:
  - preferred_term: Proteinuria
    term:
      id: HP:0000093
      label: Proteinuria
  target_mechanisms:
  - target: Anti-Gd-IgA1 Autoantibody Production and Immune Complex Assembly
    description: >-
      Cyclophosphamide and mycophenolate mofetil broadly suppress antibody
      responses, reducing the pathogenic immune-complex load.
  evidence:
  - reference: PMID:40975525
    reference_title: "Executive summary of the KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV)."
    supports: PARTIAL
    evidence_source: OTHER
    snippet: >-
      Little has changed for special situations of IgA-dominant immune complex
      glomerular diseases such as nephrotic syndrome, acute kidney injury, rapidly
      progressive glomerulonephritis, and pregnancy in IgAN, or children with
      IgAN or IgAV, given the lack of major clinical trials in these patient
      populations.
    explanation: >-
      KDIGO 2025 acknowledges a lack of major randomized trials specifically in
      IgAV; immunosuppressive regimens for severe IgAVN are extrapolated from
      IgAN evidence.

- name: Rituximab for Adult Relapsing or Severe IgAV
  description: >-
    Rituximab is a B-cell-depleting anti-CD20 monoclonal antibody under
    prospective Phase III evaluation with glucocorticoids for newly diagnosed or
    relapsing adult IgAV. Existing support is partial because the trial is active
    and results are not yet available.
  treatment_term:
    preferred_term: pharmacotherapy
    term:
      id: MAXO:0000058
      label: pharmacotherapy
    therapeutic_agent:
    - preferred_term: rituximab
      term:
        id: NCIT:C1702
        label: Rituximab
  target_phenotypes:
  - preferred_term: Palpable purpura
    term:
      id: HP:0031363
      label: Palpable purpura
  - preferred_term: Abdominal pain
    term:
      id: HP:0002027
      label: Abdominal pain
  - preferred_term: Proteinuria
    term:
      id: HP:0000093
      label: Proteinuria
  target_mechanisms:
  - target: Anti-Gd-IgA1 Autoantibody Production and Immune Complex Assembly
    description: >-
      B-cell depletion may reduce pathogenic anti-Gd-IgA1 antibody responses
      and downstream immune-complex formation.
  evidence:
  - reference: clinicaltrials:NCT05329090
    reference_title: "Evaluation of Glucocorticoids Plus Rituximab Compared to Glucocorticoids Plus Placebo for the Treatment of Patients with Newly-Diagnosed or Relapsing IgA Vasculitis: a Prospective, Randomized, Controlled, Double-blind Study"
    supports: PARTIAL
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Recently, a multicenter observational study suggested that RTX was an
      effective and safe therapeutic option for treating relapsed and / or
      refractory adult IgAV.
    explanation: >-
      Supports rituximab as a plausible IgAV therapy under prospective trial
      evaluation, while results remain pending.

diagnosis:
- name: Clinical and Biopsy-Based Diagnosis
  description: >-
    IgAV diagnosis is primarily clinical: palpable purpura with one or more of
    arthritis/arthralgia, abdominal pain, renal involvement, or IgA deposits on
    biopsy satisfies EULAR/PRINTO/PRES 2010 criteria. Skin biopsy showing IgA
    deposits in small vessel walls provides diagnostic confirmation. Kidney biopsy
    in IgAVN shows mesangial IgA deposits on immunofluorescence, identical to
    IgAN histology, and is graded by the Oxford MEST-C classification.
  evidence:
  - reference: PMID:40069065
    reference_title: "IgA Vasculitis and IgA Nephropathy: Two Sides of the Same Coin?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Due to characteristic skin rash, IgAVN patients are diagnosed precociously.
    explanation: >-
      Highlights that the characteristic palpable purpura of IgAV enables early
      clinical diagnosis, allowing renal involvement to be detected at an earlier
      stage than in IgAN.

histopathology:
- name: Leukocytoclastic Vasculitis with IgA Deposits
  description: >-
    IgAV tissue pathology is defined by IgA-dominant immune deposition in
    affected small vessels and renal lesions that overlap with IgA nephropathy.
    GI mucosal biopsy may show diagnostic IgA deposition, and renal biopsy shows
    IgAVN lesions indistinguishable from IgAN with relatively frequent
    proliferative lesions such as endocapillary hypercellularity and crescents.
  evidence:
  - reference: PMID:32803924
    reference_title: "Henoch-Schönlein Purpura (IgA Vasculitis): Rapid Evidence Review."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Henoch-Schönlein purpura, now called immunoglobulin A (IgA) vasculitis, is
      a systemic, immune complex-mediated, small-vessel leukocytoclastic
      vasculitis characterized by nonthrombocytopenic palpable purpura,
      arthritis, and abdominal pain.
    explanation: >-
      Supports the leukocytoclastic small-vessel vasculitis framing for IgAV
      tissue pathology.
  - reference: PMID:39497734
    reference_title: "Gastrointestinal manifestations and pathogenesis in childhood immunoglobulin A vasculitis."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The GI mucosal involvement when evaluated microscopically shows IgA
      deposition which is histologically diagnostic.
    explanation: >-
      Confirms that IgA deposition on mucosal biopsy is histologically diagnostic
      for GI involvement in IgAV.
  - reference: PMID:40069065
    reference_title: "IgA Vasculitis and IgA Nephropathy: Two Sides of the Same Coin?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      On kidney biopsy, the two diseases are indistinguishable, and the
      established histological Oxford classification for IgAN will soon be
      validated for IgAVN.
    explanation: >-
      Supports the renal histopathology claim that IgAVN biopsy lesions overlap
      with IgA nephropathy.

differential_diagnoses:
- name: IgA Nephropathy
  disease_term:
    preferred_term: IgA nephropathy
    term:
      id: MONDO:0005342
      label: IgA glomerulonephritis
  description: >-
    IgAN and IgAVN share identical Gd-IgA1 pathomechanism and indistinguishable
    renal biopsy findings. The key distinguishing feature is the presence of
    systemic vasculitic manifestations in IgAV (palpable purpura, arthritis, GI
    vasculitis) that are absent in kidney-limited IgAN.
  distinguishing_features:
  - Palpable purpura and extra-renal vasculitic features are present in IgAV but absent in IgAN.
  - Kidney biopsy alone cannot distinguish IgAVN from IgAN; clinical context is essential.
  - Younger age and post-infectious trigger favor IgAV; adult onset without systemic features favors IgAN.
  - IgAVN tends to have more proliferative lesions while IgAN accumulates more chronic sclerosing lesions.
  evidence:
  - reference: PMID:40069065
    reference_title: "IgA Vasculitis and IgA Nephropathy: Two Sides of the Same Coin?"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      IgA vasculitis (IgAV) is considered a systemic form of IgA nephropathy
      (IgAN). The two diseases share similar geographic and ethnic distribution,
      along with common variants in genetic association studies.
    explanation: >-
      Establishes mechanistic kinship between IgAV and IgAN while supporting
      the split decision: IgAV systemic vasculitic manifestations warrant
      separate disease representation from kidney-limited IgAN.

prevalence:
- population: Children
  percentage: "Most common systemic vasculitis in childhood"
  notes: >-
    IgAV is primarily a pediatric vasculitis but can also occur in adults.
    Most cases resolve spontaneously, while a subset have renal involvement
    that can persist or relapse and drives long-term prognosis.
  evidence:
  - reference: PMID:39497734
    reference_title: "Gastrointestinal manifestations and pathogenesis in childhood immunoglobulin A vasculitis."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Immunoglobulin A vasculitis (IgAV), previously known as Henoch-Schönlein
      purpura, is the most common form of systemic vasculitis in childhood.
    explanation: >-
      Confirms IgAV as the most prevalent systemic vasculitis in the pediatric
      population.

clinical_trials:
- name: NCT05329090
  phase: PHASE_III
  status: ACTIVE_NOT_RECRUITING
  description: >-
    RIGA is a prospective, randomized, controlled, double-blind Phase III trial
    evaluating glucocorticoids plus rituximab versus glucocorticoids plus placebo
    for induction of remission in adults with newly diagnosed or relapsing IgA
    vasculitis.
  target_phenotypes:
  - preferred_term: Palpable purpura
    term:
      id: HP:0031363
      label: Palpable purpura
  - preferred_term: Abdominal pain
    term:
      id: HP:0002027
      label: Abdominal pain
  - preferred_term: Proteinuria
    term:
      id: HP:0000093
      label: Proteinuria
  evidence:
  - reference: clinicaltrials:NCT05329090
    reference_title: "Evaluation of Glucocorticoids Plus Rituximab Compared to Glucocorticoids Plus Placebo for the Treatment of Patients with Newly-Diagnosed or Relapsing IgA Vasculitis: a Prospective, Randomized, Controlled, Double-blind Study"
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Overall, RTX may be an effective and safe therapeutic approach in adult
      IgAVs, justifying the need for a prospective randomized controlled trial
      evaluating Rituximab as an induction of remission for adult IgAV.
    explanation: >-
      ClinicalTrials.gov documents an IgAV-specific randomized rituximab trial
      for induction of remission in adult IgAV.

classifications:
  harrisons_chapter:
  - classification_value: autoimmune disease
  - classification_value: vascular disease
  - classification_value: kidney disorder

references:
- reference: PMID:40069065
  title: "IgA Vasculitis and IgA Nephropathy: Two Sides of the Same Coin?"
  findings: []
- reference: PMID:38828518
  title: "Immunoglobulin A vasculitis: The clinical features and pathophysiology."
  findings: []
- reference: PMID:39497734
  title: "Gastrointestinal manifestations and pathogenesis in childhood immunoglobulin A vasculitis."
  findings: []
- reference: PMID:40975525
  title: "Executive summary of the KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV)."
  findings: []
- reference: PMID:32803924
  title: "Henoch-Schönlein Purpura (IgA Vasculitis): Rapid Evidence Review."
  findings: []
- reference: PMID:34858429
  title: "Pathogenesis of IgA Vasculitis: An Up-To-Date Review."
  findings: []
📚

References & Deep Research

References

6
PMID:40069065
IgA Vasculitis and IgA Nephropathy: Two Sides of the Same Coin?
No top-level findings curated for this source.
PMID:38828518
Immunoglobulin A vasculitis: The clinical features and pathophysiology.
No top-level findings curated for this source.
PMID:39497734
Gastrointestinal manifestations and pathogenesis in childhood immunoglobulin A vasculitis.
No top-level findings curated for this source.
PMID:40975525
Executive summary of the KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV).
No top-level findings curated for this source.
PMID:32803924
Henoch-Schönlein Purpura (IgA Vasculitis): Rapid Evidence Review.
No top-level findings curated for this source.
PMID:34858429
Pathogenesis of IgA Vasculitis: An Up-To-Date Review.
No top-level findings curated for this source.

Deep Research

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Disease Characteristics Research Template
Edison Scientific Literature 55 citations 2026-04-28T20:28:53.336320

Question: You are an expert researcher providing comprehensive, well-cited information.

Provide detailed information focusing on: 1. Key concepts and definitions with current understanding 2. Recent developments and latest research (prioritize 2023-2024 sources) 3. Current applications and real-world implementations 4. Expert opinions and analysis from authoritative sources 5. Relevant statistics and data from recent studies

Format as a comprehensive research report with proper citations. Include URLs and publication dates where available. Always prioritize recent, authoritative sources and provide specific citations for all major claims.

Disease Characteristics Research Template

Target Disease

  • Disease Name: IgA Vasculitis
  • MONDO ID: (if available)
  • Category: Autoimmune

Research Objectives

Please provide a comprehensive research report on IgA Vasculitis covering all of the disease characteristics listed below. This report will be used to populate a disease knowledge base entry. Be thorough and cite primary literature (PMID preferred) for all claims.

For each section, suggested databases/resources are listed. These are the first places you should search for information on each topic.

1. Disease Information

Search first: OMIM, Orphanet, ICD-10/ICD-11, MeSH, PubMed

  • What is the disease? Provide a concise overview.
  • What are the key identifiers? (OMIM, Orphanet, ICD-10/ICD-11, MeSH, Mondo)
  • What are the common synonyms and alternative names?
  • Is the information derived from individual patients (e.g., EHR) or aggregated disease-level resources?

2. Etiology

  • Disease Causal Factors: What are the primary causes? (genetic, environmental, infectious, mechanistic)
  • Risk Factors:

    Search first: PubMed, Cochrane Library, UpToDate, clinical guidelines, ClinVar, ClinGen, GWAS Catalog, PheGenI, CTD, CDC, WHO, epidemiological databases

  • Genetic risk factors (causal variants, susceptibility loci, modifier genes)
  • Environmental risk factors (toxins, lifestyle, occupational exposures, age, sex, family history)
  • Protective Factors:

    Search first: PubMed, Cochrane Library, clinical trial databases, GWAS Catalog, gnomAD, WHO, CDC, nutrition databases

  • Genetic protective factors (protective variants, modifier alleles)
  • Environmental protective factors (diet, lifestyle, exposures that reduce risk)
  • Gene-Environment Interactions: How do genetic and environmental factors interact to influence disease?

    Search first: CTD, PubMed, PheGenI, GxE databases

3. Phenotypes

Search first: HPO (Human Phenotype Ontology), OMIM, Orphanet, PubMed, clinicaltrials.gov, MedDRA, SNOMED CT, DECIPHER, LOINC

For each phenotype, provide: - Phenotype type: symptoms, clinical signs, physical manifestations, behavioral changes, or laboratory abnormalities

For symptoms/signs: HPO, OMIM, Orphanet, PubMed For behavioral changes: HPO, DSM, RDoC (Research Domain Criteria), PubMed For laboratory abnormalities: LOINC, SNOMED CT, LabTests Online, PubMed - Phenotype characteristics: Search first: OMIM, Orphanet, HPO, PubMed - Age of symptom onset (neonatal, childhood, adult-onset, late-onset) - Symptom severity (mild, moderate, severe, variable) - Symptom progression (stable, progressive, episodic, fluctuating) - Frequency among affected individuals (percentage or qualitative) - Quality of life impact: Effects on daily functioning and well-being (per-phenotype when possible) Search first: EQ-5D database, SF-36, WHO QOL databases, PubMed - Suggest HPO (Human Phenotype Ontology) terms for each phenotype

4. Genetic/Molecular Information

  • Causal Genes: Gene mutations or chromosomal abnormalities responsible for disease (gene symbols, OMIM IDs)

    Search first: OMIM, ClinVar, HGMD, Ensembl, NCBI Gene

  • Pathogenic Variants:
  • Affected genes (gene symbols, HGNC IDs) > Search first: OMIM, NCBI Gene, Ensembl, HGNC, UniProt, GeneCards
  • Variant classification (pathogenic, likely pathogenic, VUS per ACMG/AMP guidelines) > Search first: ClinVar, ClinGen, ACMG/AMP guidelines, VarSome
  • Variant type/class (missense, frameshift, nonsense, splice-site, structural)
  • Allele frequency in population databases > Search first: gnomAD, 1000 Genomes, ExAC, TOPMed, dbSNP
  • Somatic vs germline origin > Search first: COSMIC (somatic), ClinVar, ICGC, TCGA
  • Functional consequences (loss of function, gain of function, dominant negative)
  • Modifier Genes: Genes that modify disease severity or expression
  • Epigenetic Information: DNA methylation, histone modifications, chromatin changes affecting disease

    Search first: ENCODE, Roadmap Epigenomics, MethBase, DiseaseMeth

  • Chromosomal Abnormalities: Large-scale genetic changes (aneuploidy, translocations, inversions)

    Search first: DECIPHER, ClinVar, ECARUCA, UCSC Genome Browser

5. Environmental Information

  • Environmental Factors: Non-genetic contributing factors (toxins, radiation, pollution, occupational exposure)

    Search first: CTD (Comparative Toxicogenomics Database), TOXNET, PubMed, EPA databases

  • Lifestyle Factors: Behavioral factors (smoking, diet, exercise, alcohol consumption)

    Search first: CDC databases, WHO, PubMed, NHANES

  • Infectious Agents: If applicable, pathogens causing or triggering disease (bacteria, viruses, fungi, parasites)

    Search first: NCBI Taxonomy, ViPR, BV-BRC, MicrobeDB, GIDEON

6. Mechanism / Pathophysiology

  • Molecular Pathways: Specific signaling cascades or biochemical pathways involved (Wnt, MAPK, mTOR, PI3K-AKT, etc.)

    Search first: KEGG, Reactome, WikiPathways, PathBank, BioCyc

  • Cellular Processes: Cell-level mechanisms (apoptosis, autophagy, cell cycle dysregulation, inflammation, etc.)

    Search first: Gene Ontology (GO), Reactome, KEGG, PubMed

  • Protein Dysfunction: How protein structure or function is altered (misfolding, aggregation, loss of function, gain of function)

    Search first: UniProt, PDB (Protein Data Bank), InterPro, Pfam, AlphaFold

  • Metabolic Changes: Alterations in metabolic processes (energy metabolism, lipid metabolism, amino acid metabolism)

    Search first: KEGG, BioCyc, HMDB (Human Metabolome Database), BRENDA

  • Immune System Involvement: Role of immune response (autoimmunity, immunodeficiency, chronic inflammation)

    Search first: ImmPort, Immunome Database, IEDB, Gene Ontology

  • Tissue Damage Mechanisms: How tissues/ are injured (oxidative stress, ischemia, fibrosis, necrosis)

    Search first: PubMed, Gene Ontology, Reactome

  • Biochemical Abnormalities: Specific molecular defects (enzyme deficiencies, receptor dysfunction, ion channel defects)

    Search first: BRENDA, UniProt, KEGG, OMIM, PubMed

  • Epigenetic Changes: DNA methylation, histone modifications affecting gene expression in disease

    Search first: ENCODE, Roadmap Epigenomics, MethBase, DiseaseMeth

  • Molecular Profiling (if available):
  • Transcriptomics/gene expression changes > Search first: GEO (Gene Expression Omnibus), ArrayExpress, GTEx, Human Cell Atlas, SRA
  • Proteomics findings > Search first: PRIDE, ProteomeXchange, Human Protein Atlas, STRING, BioGRID
  • Metabolomics signatures > Search first: MetaboLights, Metabolomics Workbench, HMDB, METLIN
  • Lipidomics alterations > Search first: LIPID MAPS, SwissLipids, LipidHome, Metabolomics Workbench
  • Genomic structural features > Search first: UCSC Genome Browser, Ensembl, NCBI, dbVar, DGV
  • Advanced Technologies (if applicable):
  • Single-cell analysis findings (cell-type specific mechanisms, cellular heterogeneity) > Search first: Human Cell Atlas, Single Cell Portal, GEO, CELLxGENE
  • Spatial transcriptomics findings > Search first: GEO, Spatial Research, Vizgen, 10x Genomics data
  • Multi-omics integration results > Search first: TCGA, ICGC, cBioPortal, LinkedOmics, PubMed
  • Functional genomics screens (CRISPR, RNAi) > Search first: DepMap, GenomeRNAi, PubMed, BioGRID ORCS

For each mechanism, describe: - The causal chain from initial trigger to clinical manifestation - Which mechanisms are upstream vs downstream - What cell types and biological processes are involved - Suggest GO terms for biological processes and CL terms for cell types

7. Anatomical Structures Affected

  • Organ Level:
  • Primary organs directly affected
  • Secondary organ involvement (complications, secondary effects)
  • Body systems involved (cardiovascular, nervous, digestive, respiratory, endocrine, etc.)

    Search first: Uberon, FMA (Foundational Model of Anatomy), OMIM, HPO, ICD-11, MeSH, SNOMED CT

  • Tissue and Cell Level:
  • Specific tissue types affected (epithelial, connective, muscle, nervous)
  • Specific cell populations targeted (with Cell Ontology terms)

    Search first: Uberon, Human Protein Atlas, Cell Ontology, Human Cell Atlas, CellMarker, PanglaoDB

  • Subcellular Level:
  • Cellular compartments involved (mitochondria, nucleus, ER, lysosomes) (with GO Cellular Component terms)

    Search first: Gene Ontology (Cellular Component), UniProt, Human Protein Atlas

  • Localization:
  • Specific anatomical sites (with UBERON terms) > Search first: FMA, Uberon, NeuroNames (for brain), SNOMED CT
  • Lateralization (unilateral, bilateral, asymmetric) > Search first: HPO, clinical literature, imaging databases

8. Temporal Development

  • Onset:
  • Typical age of onset (congenital, pediatric, adult, geriatric)
  • Onset pattern (acute, subacute, chronic, insidious)

    Search first: OMIM, Orphanet, HPO, PubMed

  • Progression:
  • Disease stages (early, intermediate, advanced, end-stage) > Search first: Cancer Staging Manual (AJCC), WHO classifications, PubMed
  • Progression rate (rapid, slow, variable)
  • Disease course pattern (episodic, relapsing-remitting, progressive, stable)
  • Disease duration (self-limited, chronic lifelong)

    Search first: Disease registries, longitudinal cohort databases, natural history studies, PubMed, Orphanet, OMIM

  • Patterns:
  • Remission patterns (spontaneous, treatment-induced) > Search first: Clinical trial databases, disease registries, PubMed
  • Critical periods (time windows of vulnerability or opportunity for intervention) > Search first: PubMed, developmental biology databases, clinical guidelines

9. Inheritance and Population

  • Epidemiology:
  • Prevalence (cases per 100,000 at given time)
  • Incidence (new cases per 100,000 per year)

    Search first: Orphanet, CDC, WHO, GBD (Global Burden of Disease), national registries, SEER, disease registries

  • For Genetic Etiology:
  • Inheritance pattern (AD, AR, X-linked, mitochondrial, multifactorial, polygenic) > Search first: OMIM, Orphanet, ClinVar, GTR (Genetic Testing Registry)
  • Penetrance (complete, incomplete, age-dependent) > Search first: ClinVar, OMIM, PubMed, ClinGen
  • Expressivity (variable, consistent) > Search first: OMIM, ClinVar, PubMed
  • Genetic anticipation (increasing severity in successive generations) > Search first: OMIM, PubMed (especially for repeat expansion disorders)
  • Germline mosaicism > Search first: ClinVar, OMIM, genetic counseling literature, PubMed
  • Founder effects (population-specific mutations) > Search first: gnomAD, population genetics databases, PubMed
  • Consanguinity role > Search first: OMIM, population studies, genetic counseling resources
  • Carrier frequency > Search first: gnomAD, carrier screening databases, GeneReviews, GTR
  • Population Demographics:
  • Affected populations (ethnic or demographic groups with higher prevalence) > Search first: gnomAD, 1000 Genomes, PAGE Study, PubMed, population registries
  • Geographic distribution (endemic areas, regional variation) > Search first: WHO, CDC, GBD, Orphanet, geographic epidemiology databases
  • Geographic distribution of specific variants
  • Sex ratio (male:female) > Search first: Disease registries, OMIM, PubMed, epidemiological databases
  • Age distribution of affected individuals > Search first: CDC, disease registries, SEER, Orphanet

10. Diagnostics

  • Clinical Tests:
  • Laboratory tests (blood, urine, tissue chemistry, specific enzyme assays) > Search first: LOINC, LabTests Online, PubMed
  • Biomarkers (proteins, metabolites, genetic markers, circulating biomarkers) > Search first: FDA Biomarker List, BEST (Biomarkers, EndpointS, and other Tools), PubMed
  • Imaging studies (X-ray, CT, MRI, PET, ultrasound) > Search first: RadLex, DICOM, Radiopaedia, imaging databases
  • Functional tests (pulmonary function, cardiac stress tests) > Search first: LOINC, clinical guidelines, PubMed
  • Electrophysiology (EEG, EMG, ECG, nerve conduction studies) > Search first: LOINC, clinical neurophysiology databases, PubMed
  • Biopsy findings (histopathology, immunohistochemistry) > Search first: SNOMED CT, College of American Pathologists resources, PubMed
  • Pathology findings (microscopic examination) > Search first: SNOMED CT, Digital Pathology databases, PubMed
  • Genetic Testing:

    Search first: GTR (Genetic Testing Registry), GeneReviews, ClinGen

  • Overview of recommended genetic testing approach
  • Whole genome sequencing (WGS) utility > Search first: GTR, ClinVar, GEL (Genomics England), gnomAD
  • Whole exome sequencing (WES) utility > Search first: GTR, ClinVar, OMIM, GeneMatcher
  • Gene panels (which panels, which genes) > Search first: GTR, ClinVar, laboratory-specific databases
  • Single gene testing > Search first: GTR, ClinVar, OMIM, GeneReviews
  • Chromosomal microarray (CMA) > Search first: DECIPHER, ClinVar, dbVar, ECARUCA
  • Karyotyping > Search first: Chromosome Abnormality Database, ClinVar, cytogenetics resources
  • FISH > Search first: ClinVar, cytogenetics databases, PubMed
  • Mitochondrial DNA testing > Search first: MITOMAP, MSeqDR, ClinVar, GTR
  • Repeat expansion testing > Search first: GTR, ClinVar, repeat expansion databases, PubMed
  • Omics-Based Diagnostics (if applicable):
  • RNA sequencing / transcriptomics > Search first: GEO, ArrayExpress, GTEx, RNA-seq databases
  • Proteomics > Search first: PRIDE, ProteomeXchange, FDA Biomarker database
  • Metabolomics > Search first: MetaboLights, Metabolomics Workbench, HMDB
  • Epigenomics > Search first: GEO, ENCODE, Roadmap Epigenomics, MethBase
  • Liquid biopsy > Search first: COSMIC, ClinVar, liquid biopsy databases, PubMed
  • Clinical Criteria:
  • Standardized diagnostic criteria (DSM, ICD, society guidelines) > Search first: DSM-5, ICD-11, clinical society guidelines, UpToDate
  • Differential diagnosis (other conditions to rule out, with distinguishing features) > Search first: DynaMed, UpToDate, clinical decision support systems
  • Screening:
  • Screening methods for asymptomatic individuals (newborn screening, carrier screening, cascade screening) > Search first: ACMG recommendations, CDC newborn screening, GTR

11. Outcome/Prognosis

  • Survival and Mortality:
  • Survival rate (5-year, 10-year, overall) > Search first: SEER, cancer registries, disease-specific registries, PubMed
  • Life expectancy (with and without treatment if applicable) > Search first: Orphanet, disease registries, actuarial databases, PubMed
  • Mortality rate > Search first: CDC, WHO, GBD, national mortality databases
  • Disease-specific mortality (deaths directly attributable to disease) > Search first: Disease registries, CDC Wonder, GBD, PubMed
  • Morbidity and Function:
  • Morbidity (disease-related disability and health impacts) > Search first: GBD, WHO, disability databases, PubMed
  • Disability outcomes (long-term functional impairments) > Search first: ICF (International Classification of Functioning), disability registries
  • Quality of life measures (EQ-5D, SF-36, PROMIS, disease-specific tools) > Search first: EQ-5D database, SF-36, PROMIS, PubMed
  • Disease Course:
  • Complications (secondary problems: infections, organ failure, etc.) > Search first: ICD codes, disease registries, clinical databases, PubMed
  • Recovery potential (likelihood and extent of recovery, with vs without treatment) > Search first: Natural history studies, rehabilitation databases, PubMed
  • Prediction:
  • Prognostic factors (age, disease severity, biomarkers, treatment response) > Search first: Prognostic models databases, clinical calculators, PubMed
  • Prognostic biomarkers (molecular markers predicting disease course) > Search first: FDA Biomarker database, PubMed, cancer prognostic databases

12. Treatment

  • Pharmacotherapy:
  • Pharmacological treatments (drug names, drug classes, mechanisms of action) > Search first: DrugBank, RxNorm, ATC classification, DailyMed, FDA databases
  • Pharmacogenomics (how genetic variants affect drug metabolism, efficacy, toxicity) > Search first: PharmGKB, CPIC (Clinical Pharmacogenetics), FDA Table of PGx Biomarkers
  • Advanced Therapeutics:
  • Gene therapy (viral vectors, CRISPR, gene replacement, gene editing) > Search first: ClinicalTrials.gov, FDA gene therapy database, ASGCT resources
  • Cell therapy (stem cell transplant, CAR-T, cellular therapeutics) > Search first: ClinicalTrials.gov, FDA cell therapy database, FACT standards
  • RNA-based therapies (ASOs, siRNA, mRNA therapies) > Search first: ClinicalTrials.gov, FDA approvals, PubMed
  • Targeted therapies (treatments directed at specific molecular targets) > Search first: My Cancer Genome, OncoKB, ClinicalTrials.gov, FDA approvals
  • Immunotherapies (checkpoint inhibitors, monoclonal antibodies) > Search first: Cancer Immunotherapy Database, FDA approvals, ClinicalTrials.gov
  • Surgical and Interventional:
  • Surgical interventions (types of surgery, timing, outcomes) > Search first: CPT codes, surgical registries, clinical guidelines, PubMed
  • Supportive and Rehabilitative:
  • Supportive care (symptom management, pain control, nutrition) > Search first: Clinical guidelines, Cochrane Library, PubMed
  • Rehabilitation (physical therapy, occupational therapy, speech therapy) > Search first: Rehabilitation medicine databases, clinical guidelines, PubMed
  • Experimental:
  • Experimental treatments in clinical trials (with NCT identifiers if available) > Search first: ClinicalTrials.gov, EU Clinical Trials Register, WHO ICTRP
  • Treatment Outcomes:
  • Treatment response rates > Search first: Clinical trial databases, FDA reviews, systematic reviews, PubMed
  • Side effects and adverse events > Search first: FDA Adverse Event Reporting System (FAERS), MedWatch, PubMed
  • Treatment Strategy:
  • Treatment algorithms (clinical pathways, decision trees) > Search first: Clinical practice guidelines, NCCN Guidelines, UpToDate
  • Combination therapies > Search first: ClinicalTrials.gov, treatment guidelines, PubMed
  • Personalized medicine approaches (genotype-guided treatment) > Search first: My Cancer Genome, CIViC, PharmGKB, precision medicine databases

For each treatment, suggest MAXO (Medical Action Ontology) terms where applicable.

13. Prevention

  • Prevention Levels:
  • Primary prevention (preventing disease occurrence: vaccination, risk factor modification) > Search first: CDC, WHO, USPSTF recommendations, Cochrane Library
  • Secondary prevention (early detection and treatment: screening programs, early intervention) > Search first: USPSTF, CDC screening guidelines, WHO
  • Tertiary prevention (preventing complications in those with disease) > Search first: Clinical guidelines, disease management protocols, PubMed
  • Immunization: Vaccine strategies (if applicable)

    Search first: CDC vaccine schedules, WHO immunization, FDA vaccine database

  • Screening and Early Detection:
  • Screening programs (population-based: newborn screening, cancer screening) > Search first: CDC screening programs, USPSTF, cancer screening databases
  • Genetic screening (carrier screening, preimplantation genetic diagnosis, prenatal testing) > Search first: ACMG recommendations, ACOG guidelines, GTR
  • Risk stratification (identifying high-risk individuals for targeted prevention) > Search first: Risk prediction models, clinical calculators, PubMed
  • Behavioral Interventions: Lifestyle modifications to reduce risk

    Search first: CDC, WHO, behavioral intervention databases, Cochrane Library

  • Counseling: Genetic counseling (risk assessment, family planning guidance)

    Search first: NSGC resources, ACMG guidelines, GeneReviews

  • Public Health:
  • Public health interventions (sanitation, vector control, health education) > Search first: CDC, WHO, public health databases, PubMed
  • Environmental interventions (reducing environmental risk factors) > Search first: EPA databases, WHO environmental health, PubMed
  • Prophylaxis: Preventive medications or procedures

    Search first: Clinical guidelines, FDA approvals, PubMed

14. Other Species / Natural Disease

  • Taxonomy: Species affected (with NCBI Taxon identifiers)

    Search first: NCBI Taxonomy

  • Breed: Specific breeds affected (with VBO identifiers if applicable)

    Search first: VBO (Vertebrate Breed Ontology)

  • Gene: Orthologous genes in other species (with NCBI Gene IDs)

    Search first: NCBI Gene

  • Natural Disease:
  • Naturally occurring disease in other species (companion animals, wildlife) > Search first: OMIA (Online Mendelian Inheritance in Animals), VetCompass, PubMed
  • Veterinary relevance and importance in animal health > Search first: OMIA, veterinary databases, PubMed
  • Comparative Biology:
  • Comparative pathology (similarities and differences across species) > Search first: OMIA, comparative pathology databases, PubMed
  • Evolutionary conservation of disease mechanisms > Search first: HomoloGene, OrthoMCL, Alliance of Genome Resources
  • Transmission (if applicable):
  • Zoonotic potential > Search first: CDC zoonotic diseases, WHO zoonoses, GIDEON
  • Cross-species susceptibility > Search first: NCBI Taxonomy, veterinary databases, PubMed

15. Model Organisms

  • Model Types:
  • Model organism type (mammalian, invertebrate, cellular, in vitro) > Search first: Alliance of Genome Resources, model organism databases
  • Specific model systems (mouse, rat, zebrafish, Drosophila, C. elegans, yeast, cell lines, organoids, iPSCs) > Search first: MGI, RGD, ZFIN, FlyBase, WormBase, SGD, ATCC, Cellosaurus
  • Induced models (drug treatment, surgical intervention, environmental manipulation) > Search first: MGI, model organism databases, PubMed
  • Genetic Models:
  • Types available (knockout, knock-in, transgenic, conditional, humanized) > Search first: MGI, IMPC, KOMP, EuMMCR, IMSR
  • Model Characteristics:
  • Phenotype recapitulation (how well model reproduces human disease features) > Search first: Model organism databases, comparative studies, PubMed
  • Model limitations (aspects of human disease not captured) > Search first: Model organism databases, PubMed, review articles
  • Applications:
  • Research applications (what aspects of disease can be studied) > Search first: Model organism databases, PubMed
  • Resources:
  • Model databases > Search first: MGI, RGD, ZFIN, FlyBase, WormBase, IMSR, EMMA, MMRRC

Citation Requirements

  • Cite primary literature (PMID preferred) for all mechanistic and clinical claims
  • Prioritize recent reviews and landmark papers
  • Include direct quotes from abstracts where possible to support key statements
  • Distinguish evidence source types: human clinical, model organism, in vitro, computational

Output Format

Structure your response as a comprehensive narrative organized by the sections above. For each section, provide: - Factual content with specific details (numbers, percentages, gene names, variant nomenclature) - Ontology term suggestions (HPO, GO, CL, UBERON, CHEBI, MAXO, MONDO) where applicable - Evidence citations with PMIDs - Direct quotes from abstracts to support key claims - Clear indication when information is not available or not applicable for this disease

This report will be used to populate a disease knowledge base entry with: - Pathophysiology descriptions with causal chains - Gene/protein annotations (HGNC, GO terms) - Phenotype associations (HP terms) with frequencies - Cell type involvement (CL terms) - Anatomical locations (UBERON terms) - Chemical entities (CHEBI terms) - Treatment annotations (MAXO terms) - Evidence items with PMIDs and exact abstract quotes - Epidemiology, prognosis, diagnostic, and prevention information - Animal model descriptions with phenotype recapitulation details

Comprehensive Disease Characteristics Report: IgA Vasculitis (IgAV)

Executive summary

IgA vasculitis (IgAV; formerly Henoch–Schönlein purpura, HSP) is an immune-complex, leukocytoclastic small-vessel vasculitis characterized by IgA-dominant immune deposition with a clinical tetrad of palpable purpura, joint involvement, gastrointestinal (GI) manifestations, and renal disease. Contemporary understanding emphasizes multifactorial triggers (often infections) acting on a genetically susceptible background and converging on aberrant IgA biology, complement activation, and neutrophil/endothelial injury. Kidney involvement drives long-term morbidity; most pediatric cases resolve, whereas adult disease is less common but often more severe and relapsing. (sestan2023diagnosticandmanagement pages 1-2, hu2024immunoglobulinavasculitis pages 1-2, castaneda2024igavasculitis(henoch–schönlein pages 1-2)

1. Disease information

1.1 Definition and overview

  • IgAV is described as a systemic, leukocytoclastic small-vessel vasculitis (predominantly small vessels) with IgA immune-complex deposition and multisystem involvement. In a pediatric nephrology review, IgAV is “histologically characterised by infiltration of the walls of the blood vessels…by neutrophils with deposits of immune complexes containing predominantly IgA” and is “clinically manifested as purpuric rash accompanied by either gastrointestinal symptoms, arthritis, and/or nephritis.” (sestan2023diagnosticandmanagement pages 1-2)
  • A 2024 review further frames IgAV as “an immune-mediated hypersensitivity disease caused by the deposition and immune complexes in small vessels and complement activation that recruits neutrophil polymorphs.” (parums2024areviewof pages 5-6)

1.2 Key identifiers and disease classification

  • Chapel Hill nomenclature (2012 revision): the term Henoch–Schönlein purpura was replaced with IgA vasculitis (IgAV). (sestan2023diagnosticandmanagement pages 1-2)
  • Classification/diagnostic criteria used clinically: pediatric sources emphasize reliance on EULAR/PRINTO/PRES-endorsed Ankara 2008 classification criteria in practice for pediatric IgAV/IgAV nephritis due to the lack of separate diagnostic criteria for nephritis. (sestan2023diagnosticandmanagement pages 1-2)
  • ICD / MeSH / MONDO / Orphanet: these identifiers were not successfully retrieved in the accessible full-text evidence in this run; therefore, they are not reported here to avoid uncited assertions.

1.3 Synonyms and alternative names

  • IgA vasculitis (IgAV)
  • Henoch–Schönlein purpura (HSP) (sestan2023diagnosticandmanagement pages 1-2, castaneda2024igavasculitis(henoch–schönlein pages 1-2)

1.4 Evidence sources (patient-level vs aggregated)

  • Evidence herein is derived from aggregated disease-level resources (reviews and nationwide cohorts) and large EHR/registry cohorts (PEDSnet; French BNDMR) as well as single-center observational cohorts and biomarker studies. (stone2023clinicalcourseand pages 1-2, maisons2023newinsightsinto pages 1-3, hocevar2023shorttermoutcomeof pages 1-2, wright2023urinarycomplementproteins pages 1-2)

2. Etiology

2.1 Primary causal factors (mechanistic)

IgAV is best understood as an immune-complex small-vessel vasculitis driven by aberrant IgA biology and downstream inflammatory injury. - Aberrant IgA biology: IgAV is triggered by immune complexes containing “hypoglycosylated IgA deposits” in a nationwide epidemiology study’s background statement. (maisons2023newinsightsinto pages 1-3) - Reviews highlight interplay between “aberrantly glycosylated IgA, anti-endothelial cell antibodies, and neutrophils following infection triggers” as central pathogenic mechanisms. (hu2024immunoglobulinavasculitis pages 1-2) - Complement and neutrophils: IgAV pathogenesis includes “complement activation that recruits neutrophil polymorphs.” (parums2024areviewof pages 5-6)

2.2 Risk factors

Infectious/environmental triggers

  • In pediatric IgAV/IgAV nephritis review literature, “upper respiratory tract or gastrointestinal infections precede the onset of disease” in “more than 75% of patients,” and multiple bacterial/viral infections are described. (sestan2023diagnosticandmanagement pages 1-2)
  • In the French nationwide cohort introduction, “Approximately 70% of IgAV patients have well-identified triggers…primarily respiratory tract or gastrointestinal infections.” (maisons2023newinsightsinto pages 1-3)

Demographic risk factors

  • Pediatric disease predominance: “Globally, approximately 90% of the patients…are children,” and pediatric incidence is substantially higher than adult incidence. (hu2024immunoglobulinavasculitis pages 1-2)
  • Male predominance is reported in pediatric epidemiology review (male:female ~1.5:1) and stronger male predominance in adults in French nationwide cohort (sex ratio 1.57 adults). (sestan2023diagnosticandmanagement pages 1-2, maisons2023newinsightsinto pages 1-3)

Genetic susceptibility

  • Pediatric review: available GWAS to date emphasize HLA class II involvement and classify IgAV as “a prototype of a disease related to HLA class II loci.” (sestan2023diagnosticandmanagement pages 1-2)
  • A 2024 Croatian pediatric cohort found susceptibility associations with HLA-A*03, HLA-B*37, and HLA-DRB1*12 (with frequencies and p-values reported), and phenotype associations (GI involvement; nephritis) with specific HLA-DRB1 alleles. (held2024hlapolymorphismsand pages 1-2)

2.3 Protective factors

No clearly established protective environmental factors were identified in the retrieved evidence. Genetic protective HLA residues/haplotypes have been described in preprint-scale GWAS (see Genetics section), but these require peer-reviewed confirmation before being treated as definitive protective factors in a knowledge base. (liu2024genomewidestudiesdefine pages 6-8)

2.4 Gene–environment interactions

The retrieved evidence supports a model where infections frequently precede disease onset in a genetically susceptible host (HLA class II associations), consistent with gene–environment interaction; however, specific quantified interaction effects were not extracted from the available sources. (sestan2023diagnosticandmanagement pages 1-2, maisons2023newinsightsinto pages 1-3, held2024hlapolymorphismsand pages 1-2)

3. Phenotypes

3.1 Core phenotype spectrum (clinical)

A 2024 review succinctly states: “Palpable purpura, gastrointestinal symptoms, joint involvement, and renal disease characterize immunoglobulin A vasculitis (IgAV).” (hu2024immunoglobulinavasculitis pages 1-2)

Major phenotypes, characteristics, and ontology suggestions

Below are commonly described phenotypes with suggested ontology mappings (HPO terms are suggestions for knowledge-base curation; they are not asserted as exact HPO IDs in the cited sources).

1) Palpable purpura / purpuric rash - Type: clinical sign - Frequency: emphasized as “the main attribute” in pediatric IgAV review. (sestan2023diagnosticandmanagement pages 1-2) - HPO suggestion: Palpable purpura; Purpura

2) Arthralgia/arthritis (joint involvement) - Type: symptom/sign - Pediatric biomarker cohort: joint involvement in 76/86 (88.4%). (held2024insightintothe pages 2-4) - HPO suggestions: Arthralgia; Arthritis

3) Gastrointestinal involvement (abdominal pain/bleeding) - Type: symptom/sign - Pediatric biomarker cohort: GI involvement in 39/86 (45.3%). (held2024insightintothe pages 2-4) - HPO suggestions: Abdominal pain; Gastrointestinal hemorrhage

4) Renal involvement / IgA vasculitis nephritis (IgAVN) - Type: laboratory abnormality/organ involvement - Pediatric review: IgAVN occurs in 20–60% of children with IgAV. (sestan2023diagnosticandmanagement pages 1-2) - HPO suggestions: Hematuria; Proteinuria; Glomerulonephritis; Reduced glomerular filtration rate

5) Relapsing/recurrent disease - Adult cohort: relapse in 42/265 (15.8%) during median 24-month follow-up. (hocevar2023shorttermoutcomeof pages 1-2) - Pediatric biomarker cohort: at least one recurrence in 21/86 (24.4%). (held2024insightintothe pages 2-4) - HPO suggestions: Relapsing disease course

3.2 Onset and course (phenotype-level)

  • Pediatric onset: median onset around 6 years; 90% <10 years. (sestan2023diagnosticandmanagement pages 1-2)
  • Many patients are self-limited, but a subset develops refractory nephritis/chronic kidney failure (review-level statement). (hu2024immunoglobulinavasculitis pages 1-2)

3.3 Quality of life (QoL) impact

Direct QoL instrument statistics (e.g., SF-36 scores) were not extracted from the retrieved observational studies; however, a pediatric atypical-course case series reported high care utilization and psychosocial burden, including ED re-presentations and psychology referrals. Specifically, among 13 atypical pediatric cases, 10/13 (77%) re-presented to the ED and 5/13 (38%) were referred to psychology services; 7/13 (54%) reported frustration. (marro2023acaseseries pages 1-2)

4. Genetic / molecular information

4.1 Causal genes and inheritance

No monogenic causal gene model is supported by the retrieved evidence. IgAV is consistently presented as complex/multifactorial, with GWAS and candidate associations each contributing limited effect sizes. (sestan2023diagnosticandmanagement pages 1-2)

4.2 Susceptibility loci and candidate genes (recent developments prioritized)

4.2.1 Large-scale multi-omics GWAS preprint (2024)

A 2024 medRxiv preprint reports genome-/transcriptome-/proteome-wide association results in 2,170 IgAV cases and 5,928 controls, identifying HLA and non-HLA loci and proposing myeloid Fcα receptor signaling as a convergent mechanism. Reported key associations include: HLA-DRB1 OR=1.55 (P=1.1×10−25), FCAR OR=1.51 (P=1.0×10−20), and INPP5D OR=1.34 (P=2.2×10−9), with IL6R implicated by proteome-wide association. (liu2024genomewidestudiesdefine pages 2-6) - Mechanistic interpretation (from the same work): FCAR risk alleles co-localize with cis-eQTL increasing FCAR expression and disrupt a PRDM1 motif; INPP5D encodes SHIP-1, a negative regulator of FcR signaling; IL6R risk haplotypes influence soluble IL6R levels. (liu2024genomewidestudiesdefine pages 8-11, liu2024genomewidestudiesdefine pages 11-13) - Note: this is a preprint and should be treated as provisional until peer review. (liu2024genomewidestudiesdefine pages 2-6)

4.2.2 HLA associations in a 2024 Croatian pediatric cohort

In a case–control cohort (130 IgAV children; 202 controls), significant susceptibility and phenotype associations included: - Susceptibility: HLA-A*03 21.4% vs 12.38% (p=0.0092); HLA-B*37 2.9% vs 0.2% (p=0.0054); HLA-DRB1*12 3.1% vs 0.7% (p=0.0216). (held2024hlapolymorphismsand pages 1-2) - Nephritis phenotype: HLA-DRB1*14:01P 17.5% vs 4.5% (p=0.0006). (held2024hlapolymorphismsand pages 1-2) - Multivariate results also reported DRB110 association with GI symptoms and DRB114 association with nephritis. (held2024hlapolymorphismsand pages 6-8)

4.3 Molecular features and biomarkers (disease-associated)

  • Complement-related urinary biomarkers: urinary C3/C4/C5/C5a are increased in pediatric IgAV nephritis and can discriminate nephritis (AUC 0.92). (wright2023urinarycomplementproteins pages 1-2)
  • Multi-analyte biomarker exploration (2024): a pediatric cohort study investigated serum/urine Gd-IgA1, HMGB1, RAGE, and PCDH1 as potential biomarkers and reported clinical phenotype frequencies and treatment exposures (see Statistics table). (held2024insightintothe pages 2-4)

4.4 Epigenetics and chromosomal abnormalities

No epigenetic mechanisms or chromosomal abnormalities were extracted from the retrieved sources in this run.

5. Environmental information

5.1 Infectious agents

  • Respiratory and GI infections commonly precede IgAV onset. (sestan2023diagnosticandmanagement pages 1-2, maisons2023newinsightsinto pages 1-3)

5.2 Lifestyle and toxins

No specific lifestyle/toxin associations were extracted from the retrieved evidence.

6. Mechanism / pathophysiology

6.1 Current mechanistic understanding (causal chain)

A consolidated causal chain supported by the retrieved evidence: 1) Trigger (often infection) precedes onset in a large proportion of patients. (sestan2023diagnosticandmanagement pages 1-2, maisons2023newinsightsinto pages 1-3) 2) Aberrantly glycosylated/hypoglycosylated IgA and immune complexes form and deposit in tissues, with reviews referencing aberrant glycosylation and IgA1-dominant immune-complex deposition as key. (maisons2023newinsightsinto pages 1-3, castaneda2024igavasculitis(henoch–schönlein pages 1-2) 3) Complement activation and neutrophil recruitment occur; IgAV is described as involving “complement activation that recruits neutrophil polymorphs.” (parums2024areviewof pages 5-6) 4) Endothelial/vascular inflammation and organ injury manifests clinically as purpura, arthritis, GI symptoms, and nephritis. (sestan2023diagnosticandmanagement pages 1-2, hu2024immunoglobulinavasculitis pages 1-2)

6.2 Complement involvement and renal biomarkers

A prospective cohort study reports that urinary complement proteins are elevated in IgAV nephritis (IgAV-N) and can stratify nephritis. - The abstract reports: “Children with immunoglobulin A vasculitis (IgAV… ) frequently encounter nephritis (IgAV-N) with 1–2% risk of kidney failure.” (wright2023urinarycomplementproteins pages 1-2) - Quantitatively, in IgAV-N vs IgAV without nephritis, urinary complement levels were higher (e.g., C3 14.65 vs 2.26 μg/mmol) and a logistic regression model yielded AUC 0.92 (p<0.001) to discriminate nephritis. (wright2023urinarycomplementproteins pages 1-2)

6.3 Cell types and ontology suggestions

  • Neutrophils and immune-complex mediated inflammation are emphasized. (parums2024areviewof pages 5-6, sestan2023diagnosticandmanagement pages 1-2)
  • CL term suggestions: neutrophil; monocyte; macrophage; endothelial cell.

6.4 Pathway/GO term suggestions

  • GO Biological Process suggestions: complement activation; neutrophil chemotaxis; immune complex clearance; leukocyte-mediated immunity; inflammatory response.

7. Anatomical structures affected

7.1 Primary organs/systems

Commonly involved organs: skin, joints, GI tract, kidneys. (maisons2023newinsightsinto pages 1-3, sestan2023diagnosticandmanagement pages 1-2)

7.2 Ontology suggestions

  • UBERON suggestions: skin; kidney; glomerulus; small intestine; synovial joint.

8. Temporal development

8.1 Typical onset

  • Pediatric predominance with onset around early childhood; median ~6 years and 90% <10 years in one review. (sestan2023diagnosticandmanagement pages 1-2)

8.2 Disease course patterns

  • Pediatric IgAV often follows a self-limited course, but nephritis can be refractory and lead to CKD/ESKD in a minority. (hu2024immunoglobulinavasculitis pages 1-2)
  • Adult IgAV is notable for relapse and persistent urinary abnormalities: relapse 15.8%, persistent abnormal urinalysis 27.9%, and ≥20% eGFR decline 15.5% over median 24 months in a histologically proven cohort. (hocevar2023shorttermoutcomeof pages 1-2)

9. Inheritance and population

9.1 Epidemiology (recent statistics)

  • French nationwide rare-disease network cohort (BNDMR) reported 1,988 IgAV patients (2010–2022). Annual incidence in 2021 was 0.06 per 100,000 adults and 0.50 per 100,000 children. (maisons2023newinsightsinto pages 1-3)
  • Seasonality and geography: more frequent in winter/autumn and more common in the South vs North of France, adults OR 4.88 [4.17–5.74], children OR 1.51 [1.35–1.68]. (maisons2023newinsightsinto pages 1-3)
  • COVID-19 impact: pediatric incidence decreased during the pandemic period (defined in the paper), OR 0.62 [0.47–0.81]. (maisons2023newinsightsinto pages 1-3)

9.2 Genetic architecture

Evidence supports a polygenic/complex architecture with notable HLA associations; no Mendelian inheritance pattern is supported by the retrieved evidence. (sestan2023diagnosticandmanagement pages 1-2, held2024hlapolymorphismsand pages 1-2)

10. Diagnostics

10.1 Clinical criteria and routine evaluation

  • Classification criteria used for IgAV diagnosis include ACR 1990 and EULAR/PRINTO/PRES criteria, with EULAR/PRINTO/PRES noted as having better sensitivity/specificity than ACR in children/adults in a 2024 review. (hu2024immunoglobulinavasculitis pages 1-2)

10.2 Laboratory and monitoring in nephritis

A pediatric nephrology review states: “Basic investigations that should be done in every patient with IgAVN include blood pressure measurement, estimated glomerular filtration rate and urinalysis.” (sestan2023diagnosticandmanagement pages 1-2)

10.3 Biopsy

  • Kidney biopsy: “Kidney biopsy is still the gold standard for the diagnosis of IgAVN since noninvasive confirmation of nephritis is still pending.” (sestan2023diagnosticandmanagement pages 1-2)
  • Skin biopsy: a 2024 review states that biopsy with histopathology and IgA staining is “essential for the diagnosis,” and notes that renal biopsy can be done when there is clinical evidence of renal involvement. (parums2024areviewof pages 5-6)

10.4 Biomarkers (clinical readiness)

  • A 2024 review states: “Currently, no specific diagnostic serological laboratory tests or biomarkers for IgA vasculitis exist.” (parums2024areviewof pages 5-6)
  • Complement urine markers show promise for discrimination of nephritis (AUC 0.92), but this is not yet established as standard-of-care diagnostic testing. (wright2023urinarycomplementproteins pages 1-2)

11. Outcome / prognosis

11.1 Pediatric renal outcomes (EHR-based cohort)

A large PEDSnet observational cohort (diagnoses 2009–2020) reported outcomes among nephrology-followed children: - “A total of 6802 children had a diagnosis of IgAV, of whom 1139 (16.7%) were followed by nephrology for at least 2 visits over a median follow-up period of 1.7 years [0.4,4.2].” (stone2023clinicalcourseand pages 1-2) - “At the end of follow-up, 2.6 and 0.5% developed CKD and kidney failure, respectively.” (stone2023clinicalcourseand pages 1-2)

11.2 Adult outcomes

In a histologically proven adult cohort (2010–2022) with median follow-up 24 months: - Baseline renal involvement was 44.5%. (hocevar2023shorttermoutcomeof pages 1-2) - Relapse occurred in 15.8%, persistent abnormal urinalysis in 27.9%, and ≥20% eGFR decline in 15.5%. (hocevar2023shorttermoutcomeof pages 1-2) - Mortality: standardized mortality ratio (SMR) 1.4 [1.14–1.71] vs general population. (hocevar2023shorttermoutcomeof pages 1-2)

11.3 Prognostic factors

Adult review and cohort literature indicate renal function, proteinuria, and hypertension are key predictors of renal prognosis (review-level statements); detailed quantitative prognostic modeling beyond the adult cohort hazard ratios for relapse were not comprehensively extracted in this run. (audemardverger2015igavasculitis(henochshönlein pages 1-1, hocevar2023shorttermoutcomeof pages 1-2)

12. Treatment

12.1 Current real-world management patterns (pediatrics; PEDSnet)

In PEDSnet nephrology-followed children: - “Conservative management was the most predominant practice pattern, consisting of observation in 57% and RAAS blockade in 6%. Steroid monotherapy was used in 29% and other immunosuppression regimens in 8%.” (stone2023clinicalcourseand pages 1-2)

12.2 Guideline-oriented treatment stratification (pediatric IgAV nephritis)

A pediatric nephrology review summarizes SHARE-oriented first-line approaches by severity: - Mild IgAVN: “oral glucocorticoids” - Moderate IgAVN: “parenterally administrated glucocorticoids in pulsed doses” - Severe IgAVN: “pulsed doses of glucocorticoids in combination with intravenous cyclophosphamide pulses” (sestan2023diagnosticandmanagement pages 1-2)

12.3 Adult and severe disease therapeutic landscape (2024 update)

A 2024 treatment-focused review states: - “Glucocorticoids are the first-line therapy for IgAV, especially in adults with severe manifestations.” (castaneda2024igavasculitis(henoch–schönlein pages 1-2) - For minor manifestations: “Colchicine, dapsone, and methotrexate can be useful.” (castaneda2024igavasculitis(henoch–schönlein pages 1-2) - Steroid-sparing/other agents: calcineurin inhibitors and mycophenolate mofetil are cited as showing favorable results as glucocorticoid-sparing agents; rituximab is described as reducing relapse frequency and steroid burden and achieving long-term remission in some settings. (castaneda2024igavasculitis(henoch–schönlein pages 1-2)

12.4 Evidence gaps and expert opinion

  • Adult-focused expert review (2015) emphasizes uncertainty and the need for prospective RCTs; it states that corticosteroids and immunosuppressants “have not been shown to improve long-term outcomes” for severe disease in adults (review-level conclusion). (audemardverger2015igavasculitis(henochshönlein pages 1-1)
  • Pediatric nephrology review similarly notes that “noninvasive confirmation of nephritis is still pending” and highlights that “new therapeutic options are currently being tested” including those targeting Gd-IgA1/autoantibodies and complement pathways. (sestan2023diagnosticandmanagement pages 1-2)

12.5 MAXO (Medical Action Ontology) suggestions

  • Glucocorticoid therapy; RAAS inhibition; cyclophosphamide therapy; rituximab therapy; kidney biopsy; urinalysis; blood pressure monitoring; plasma exchange (for severe life-threatening situations; review-level). (sestan2023diagnosticandmanagement pages 1-2, castaneda2024igavasculitis(henoch–schönlein pages 1-2)

13. Prevention

No primary prevention strategies (e.g., vaccination, lifestyle) were identified in the retrieved evidence. Secondary/tertiary prevention is implicit in recommendations for monitoring kidney function and early management of nephritis. (hu2024immunoglobulinavasculitis pages 1-2, sestan2023diagnosticandmanagement pages 1-2)

14. Other species / natural disease

No veterinary/natural disease evidence in other species was identified in the retrieved evidence.

15. Model organisms

No IgAV-specific animal models were extracted in the retrieved evidence. (Mechanistic modeling is often discussed for IgA nephropathy; however, IgAN model evidence was outside the scope of the retrieved IgAV-focused texts in this run.)

Recent developments (2023–2024 prioritized)

1) Nationwide epidemiology shifts during COVID-19: pediatric incidence decreased during the pandemic period (OR 0.62) in the French BNDMR cohort. (Published online 12 Jul 2023; https://doi.org/10.1007/s00296-023-05387-2) (maisons2023newinsightsinto pages 1-3) 2) Large EHR-based pediatric outcome estimation: PEDSnet analysis quantified CKD (2.6%) and kidney failure (0.5%) after median 1.7 years follow-up among nephrology-followed children. (Published online 14 Jun 2023; https://doi.org/10.1007/s00467-023-06023-8) (stone2023clinicalcourseand pages 1-2) 3) Urinary complement markers for nephritis stratification: AUC 0.92 for discriminating nephritis using urinary complement analytes. (Published online 13 Oct 2022; 2023 issue; https://doi.org/10.1007/s00467-022-05747-3) (wright2023urinarycomplementproteins pages 1-2) 4) Genetic advances: HLA associations replicated in pediatric cohorts (2024 IJMS), and a 2024 multi-omics GWAS preprint proposes FcαR pathway loci (FCAR, INPP5D) and IL6R involvement. (https://doi.org/10.3390/ijms25020882; https://doi.org/10.1101/2024.10.10.24315041) (held2024hlapolymorphismsand pages 1-2, liu2024genomewidestudiesdefine pages 2-6)

Current applications and real-world implementation

  • Routine nephritis evaluation in pediatric practice includes BP measurement, eGFR, and urinalysis; kidney biopsy remains the gold standard for IgAV nephritis diagnosis when needed. (sestan2023diagnosticandmanagement pages 1-2)
  • Treatment in practice is heterogeneous and often conservative, as observed in PEDSnet (observation/RAAS blockade common; steroids/immunosuppression used in more severe presentations). (stone2023clinicalcourseand pages 1-2)
  • Adult care often relies on glucocorticoids and selected immunomodulators, with increasing interest in biologics (rituximab) and pathway-directed therapies (complement/APRIL/BAFF axis), though high-quality evidence remains limited for IgAV specifically. (castaneda2024igavasculitis(henoch–schönlein pages 1-2)

Ongoing and recent clinical trials (real-world translational pipeline)

  • NCT05329090 (RIGA): “Evaluation of Glucocorticoids Plus Rituximab in Patients with Newly-Diagnosed or Relapsing IgA Vasculitis” (Phase 3; randomized, double-blind, placebo-controlled). Primary outcome includes remission defined as alive and prednisone 0 mg/day at 180 and 360 days; status ACTIVE_NOT_RECRUITING; enrollment 75; start 2022-03-11. (https://clinicaltrials.gov/study/NCT05329090) (NCT05329090 chunk 1)
  • NCT07052981: “Clinical Study on the Efficacy and Safety of Telitacicept in the Treatment of Pediatric IgA Nephropathy or IgA Vasculitis Nephritis” (Phase 3; multicenter; non-randomized parallel groups; telitacicept + standard therapy vs standard therapy; pediatric 5–18 years; 24-week treatment; status NOT_YET_RECRUITING; enrollment 124). (https://clinicaltrials.gov/study/NCT07052981) (NCT07052981 chunk 1)

Key quantitative evidence table

The following table compiles the most decision-relevant statistics extracted from recent cohorts and biomarker studies.

Domain Finding (with exact number) Population/Study Year PMID (if available; otherwise DOI) URL Evidence citation id(s)
Epidemiology Incidence of IgAV worldwide in children: 3 to 27 cases per 100,000 children Pediatric review by Sestan & Jelusic 2023 DOI: 10.2147/PHMT.S379862 https://doi.org/10.2147/phmt.s379862 (sestan2023diagnosticandmanagement pages 1-2)
Epidemiology Prevalence of IgAV: 6.1 to 20.4 per 100,000 children Pediatric review by Sestan & Jelusic 2023 DOI: 10.2147/PHMT.S379862 https://doi.org/10.2147/phmt.s379862 (sestan2023diagnosticandmanagement pages 1-2)
Epidemiology IgAV nephritis occurs in 20–60% of children with IgAV Pediatric review by Sestan & Jelusic 2023 DOI: 10.2147/PHMT.S379862 https://doi.org/10.2147/phmt.s379862 (sestan2023diagnosticandmanagement pages 1-2)
Epidemiology Median age of onset around 6 years; 90% younger than 10 years; male:female 1.5:1 Pediatric review by Sestan & Jelusic 2023 DOI: 10.2147/PHMT.S379862 https://doi.org/10.2147/phmt.s379862 (sestan2023diagnosticandmanagement pages 1-2)
Epidemiology Total cohort 1,988 IgAV patients; sex ratio 1.57 in adults and 1.05 in children French nationwide cohort (BNDMR) 2023 DOI: 10.1007/s00296-023-05387-2 https://doi.org/10.1007/s00296-023-05387-2 (maisons2023newinsightsinto pages 1-3)
Epidemiology Annual incidence in 2021: 0.06 per 100,000 adults and 0.50 per 100,000 children French nationwide cohort (BNDMR) 2023 DOI: 10.1007/s00296-023-05387-2 https://doi.org/10.1007/s00296-023-05387-2 (maisons2023newinsightsinto pages 1-3)
Epidemiology Higher frequency in South vs North of France: adults OR 4.88 [4.17–5.74]; children OR 1.51 [1.35–1.68] French nationwide cohort (BNDMR) 2023 DOI: 10.1007/s00296-023-05387-2 https://doi.org/10.1007/s00296-023-05387-2 (maisons2023newinsightsinto pages 1-3)
Epidemiology Pediatric incidence decreased during COVID-19 period: OR 0.62 [0.47–0.81] French nationwide cohort (BNDMR) 2023 DOI: 10.1007/s00296-023-05387-2 https://doi.org/10.1007/s00296-023-05387-2 (maisons2023newinsightsinto pages 1-3)
Renal outcomes 6,802 children with IgAV; 1,139 (16.7%) followed by nephrology for at least 2 visits; median follow-up 1.7 years [0.4, 4.2] PEDSnet pediatric cohort (Stone et al.) 2023 DOI: 10.1007/s00467-023-06023-8 https://doi.org/10.1007/s00467-023-06023-8 (stone2023clinicalcourseand pages 1-2)
Renal outcomes Management patterns: observation 57%, RAAS blockade 6%, steroid monotherapy 29%, other immunosuppression 8% PEDSnet pediatric cohort (Stone et al.) 2023 DOI: 10.1007/s00467-023-06023-8 https://doi.org/10.1007/s00467-023-06023-8 (stone2023clinicalcourseand pages 1-2)
Renal outcomes End of follow-up: 2.6% developed CKD and 0.5% kidney failure PEDSnet pediatric cohort (Stone et al.) 2023 DOI: 10.1007/s00467-023-06023-8 https://doi.org/10.1007/s00467-023-06023-8 (stone2023clinicalcourseand pages 1-2)
Biomarkers Study cohort: 103 children total; 47 IgAV (37 without nephritis, 10 with IgAV-N), 30 SLE, 26 healthy controls Urinary complement study (Wright et al.) 2023 DOI: 10.1007/s00467-022-05747-3 https://doi.org/10.1007/s00467-022-05747-3 (wright2023urinarycomplementproteins pages 1-2)
Biomarkers Urinary C3 in IgAV-N vs IgAV without nephritis: 14.65 μg/mmol [2.26–20.21] vs 2.26 μg/mmol [0.15–3.14], p=0.007 Urinary complement study (Wright et al.) 2023 DOI: 10.1007/s00467-022-05747-3 https://doi.org/10.1007/s00467-022-05747-3 (wright2023urinarycomplementproteins pages 1-2)
Biomarkers Urinary C4 in IgAV-N vs IgAV without nephritis: 6.52 μg/mmol [1.30–9.72] vs 1.37 μg/mmol [0.38–2.43], p=0.04 Urinary complement study (Wright et al.) 2023 DOI: 10.1007/s00467-022-05747-3 https://doi.org/10.1007/s00467-022-05747-3 (wright2023urinarycomplementproteins pages 1-2)
Biomarkers Urinary C5 in IgAV-N vs IgAV without nephritis: 1.36 μg/mmol [0.65–2.85] vs 0.38 μg/mmol [0.03–0.72], p=0.005 Urinary complement study (Wright et al.) 2023 DOI: 10.1007/s00467-022-05747-3 https://doi.org/10.1007/s00467-022-05747-3 (wright2023urinarycomplementproteins pages 1-2)
Biomarkers Urinary C5a in IgAV-N vs IgAV without nephritis: 101.9 ng/mmol [15.36–230.0] vs 18.33 ng/mmol [4.27–33.30], p=0.01 Urinary complement study (Wright et al.) 2023 DOI: 10.1007/s00467-022-05747-3 https://doi.org/10.1007/s00467-022-05747-3 (wright2023urinarycomplementproteins pages 1-2)
Biomarkers Combined urinary complement model discriminated nephritis with AUC 0.92, p<0.001 Urinary complement study (Wright et al.) 2023 DOI: 10.1007/s00467-022-05747-3 https://doi.org/10.1007/s00467-022-05747-3 (wright2023urinarycomplementproteins pages 1-2)
Biomarkers Pediatric IgAV cohort: 86 patients; 49 girls, 37 boys; median age 6.4 years (IQR 4.5–7.8) Biomarker cohort (Held et al.) 2024 DOI: 10.3390/ijms25084383 https://doi.org/10.3390/ijms25084383 (held2024insightintothe pages 2-4)
Biomarkers Clinical features: skin changes 100%; joint involvement 76/86 (88.4%); GI involvement 39/86 (45.3%); nephritis 26/86 (30.2%); scrotal involvement 6 boys (16.2%) Biomarker cohort (Held et al.) 2024 DOI: 10.3390/ijms25084383 https://doi.org/10.3390/ijms25084383 (held2024insightintothe pages 2-4)
Biomarkers At least one recurrence in 21/86 (24.4%); median PVAS 4 (IQR 2–6) Biomarker cohort (Held et al.) 2024 DOI: 10.3390/ijms25084383 https://doi.org/10.3390/ijms25084383 (held2024insightintothe pages 2-4)
Biomarkers Treatments: NSAIDs 75/86 (87.2%); glucocorticoids 36/86 (41.8%); ACE inhibitors 15/86 (17.4%); immunosuppressants 11/86 (12.8%) Biomarker cohort (Held et al.) 2024 DOI: 10.3390/ijms25084383 https://doi.org/10.3390/ijms25084383 (held2024insightintothe pages 2-4)
Biomarkers Nephritis outcomes among nephritis subgroup: outcome A 18 (69.3%), outcome B 8 (30.7%), outcome C 0, outcome D 0 Biomarker cohort (Held et al.) 2024 DOI: 10.3390/ijms25084383 https://doi.org/10.3390/ijms25084383 (held2024insightintothe pages 2-4)
Adult outcomes Adult cohort size 265; median follow-up 24 months Adult single-center cohort (Hočevar et al.) 2023 DOI: 10.3389/fmed.2023.1210307 https://doi.org/10.3389/fmed.2023.1210307 (hocevar2023shorttermoutcomeof pages 1-2)
Adult outcomes Baseline involvement: articular 38.9%, gastrointestinal 29.8%, renal 44.5% Adult single-center cohort (Hočevar et al.) 2023 DOI: 10.3389/fmed.2023.1210307 https://doi.org/10.3389/fmed.2023.1210307 (hocevar2023shorttermoutcomeof pages 1-2)
Adult outcomes Initial treatment: systemic glucocorticoids 189 (71.3%); additional immunomodulator 32 (12.1%) Adult single-center cohort (Hočevar et al.) 2023 DOI: 10.3389/fmed.2023.1210307 https://doi.org/10.3389/fmed.2023.1210307 (hocevar2023shorttermoutcomeof pages 1-2)
Adult outcomes Relapse in 42 (15.8%); younger age associated with relapse HR 1.03 [1.01–1.05]; no baseline glucocorticoids HR 3.70 [2.0–6.67] Adult single-center cohort (Hočevar et al.) 2023 DOI: 10.3389/fmed.2023.1210307 https://doi.org/10.3389/fmed.2023.1210307 (hocevar2023shorttermoutcomeof pages 1-2)
Adult outcomes Persistent abnormal urinalysis in 74 (27.9%); ≥20% eGFR decline in 41 (15.5%) Adult single-center cohort (Hočevar et al.) 2023 DOI: 10.3389/fmed.2023.1210307 https://doi.org/10.3389/fmed.2023.1210307 (hocevar2023shorttermoutcomeof pages 1-2)
Adult outcomes Overall standardized mortality ratio 1.4 [95% CI 1.14–1.71] vs general population Adult single-center cohort (Hočevar et al.) 2023 DOI: 10.3389/fmed.2023.1210307 https://doi.org/10.3389/fmed.2023.1210307 (hocevar2023shorttermoutcomeof pages 1-2)

Table: This table compiles the main quantitative epidemiology, renal outcome, biomarker, and adult outcome statistics for IgA vasculitis from the gathered evidence. It is useful as a compact evidence map for rapid reference when drafting the full report.

Visual evidence

A table summarizing kidney outcomes stratified by management patterns (observation vs RAAS blockade vs steroids vs other immunosuppression) was retrieved from the Stone et al. PEDSnet paper (Table 5). (stone2023clinicalcourseand media 45fd3a4e)

Notes on evidence quality and limitations

  • Several key advances are based on observational cohorts (PEDSnet; BNDMR; single-center adult cohorts) and therefore are subject to confounding by indication and measurement limitations. (stone2023clinicalcourseand pages 1-2, maisons2023newinsightsinto pages 1-3, hocevar2023shorttermoutcomeof pages 1-2)
  • Genetic findings include a major 2024 medRxiv preprint with large sample size and compelling mechanistic hypotheses, but it is not yet peer-reviewed and should be curated with that caveat. (liu2024genomewidestudiesdefine pages 2-6)
  • Despite promising biomarkers (e.g., urinary complement proteins), reviews still emphasize a lack of validated diagnostic serologic biomarkers in routine clinical practice. (parums2024areviewof pages 5-6, wright2023urinarycomplementproteins pages 1-2)

References

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  15. (liu2024genomewidestudiesdefine pages 11-13): Lili Liu, Li Zhu, Sara Monteiro-Martins, Aaron Griffin, Lukas J Vlahos, Masashi Fujita, Cecilia Berrouet, Francesca Zanoni, Maddalena Marasa, Jun Y Zhang, Xu-Jie Zhou, Yasar Caliskan, Oleh Akchurin, Samhar Al-Akash, Augustina Jankauskiene, Monica Bodria, Aftab Chishti, Ciro Esposito, Vittoria Esposito, Donna Claes, Vladimir Tesar, Thomas K Davis, Dmitry Samsonov, Dorota Kaminska, Tomasz Hryszko, Gianluigi Zaza, Joseph T Flynn, Franca Iorember, Francesca Lugani, Dana Rizk, Bruce A Julian, Guillermo Hidalgo, Mahmoud Kallash, Luigi Biancone, Antonio Amoroso, Luisa Bono, Laila-Yasmin Mani, Fangming Lin, Bruno Vogt, Raji Sreedharan, Patricia Weng, Daniel Ranch, Nianzhou Xiao, Alejandro Quiroga, Raed Bou Matar, Michelle N Rheault, Scott Wenderfer, Dave Selewski, Sigrid Lundberg, Cynthia Silva, Sherene Mason, John D Mahan, Tetyana L Vasylyeva, Krzysztof Mucha, Bartosz Foroncewicz, Leszek Pączek, Michał Florczak, Małgorzata Olszewska, Agnieszka Gradzińska, Maria Szczepańska, Edyta Machura, Andrzej Badeński, Helena Krakowczyk, Przemysław Sikora, Norbert Kwella, Monika Miklaszewska, Dorota Drożdż, Marcin Zaniew, Krzysztof Pawlaczyk, Katarzyna SiniewiczLuzeńczyk, Andrew S Bomback, Gerald B Appel, Claudia Izzi, Francesco Scolari, Anna Materna-Kiryluk, Malgorzata Mizerska-Wasiak, Laureline Berthelot, Evangeline Pillebout, Renato C Monteiro, Jan Novak, Todd Jason Green, William E Smoyer, M Colleen Hastings, Robert J Wyatt, Raoul Nelson, Javier Martin, Miguel A González-Gay, Philip L De Jager, Anna Köttgen, Andrea Califano, Ali G Gharavi, Hong Zhang, and Krzysztof Kiryluk. Genome-wide studies define new genetic mechanisms of iga vasculitis. medRxiv, Oct 2024. URL: https://doi.org/10.1101/2024.10.10.24315041, doi:10.1101/2024.10.10.24315041. This article has 2 citations.

  16. (held2024hlapolymorphismsand pages 6-8): Martina Held, Katarina Stingl Jankovic, Mario Sestan, Matej Sapina, Nastasia Kifer, Sasa Srsen, Marijan Frkovic, Alenka Gagro, Zorana Grubic, and Marija Jelusic. Hla polymorphisms and clinical manifestations in iga vasculitis. International Journal of Molecular Sciences, 25:882, Jan 2024. URL: https://doi.org/10.3390/ijms25020882, doi:10.3390/ijms25020882. This article has 11 citations.

  17. (audemardverger2015igavasculitis(henochshönlein pages 1-1): Alexandra Audemard-Verger, Evangeline Pillebout, Loïc Guillevin, Eric Thervet, and Benjamin Terrier. Iga vasculitis (henoch-shönlein purpura) in adults: diagnostic and therapeutic aspects. Autoimmunity reviews, 14 7:579-85, Jul 2015. URL: https://doi.org/10.1016/j.autrev.2015.02.003, doi:10.1016/j.autrev.2015.02.003. This article has 358 citations and is from a peer-reviewed journal.

  18. (NCT05329090 chunk 1): Evaluation of Glucocorticoids Plus Rituximab in Patients with Newly-Diagnosed or Relapsing IgA Vasculitis. Hopital Foch. 2022. ClinicalTrials.gov Identifier: NCT05329090

  19. (NCT07052981 chunk 1): Guixia Ding. Clinical Study on the Efficacy and Safety of Telitacicept in the Treatment of Pediatric IgA Nephropathy or IgA Vasculitis Nephritis. Guixia Ding. 2025. ClinicalTrials.gov Identifier: NCT07052981

  20. (stone2023clinicalcourseand media 45fd3a4e): Hillarey K. Stone, Mark Mitsnefes, Kimberley Dickinson, Evanette K. Burrows, Hanieh Razzaghi, Ingrid Y. Luna, Caroline A. Gluck, Bradley P. Dixon, Vikas R. Dharnidharka, William E. Smoyer, Michael J. Somers, Joseph T. Flynn, Susan L. Furth, Charles Bailey, Christopher B. Forrest, Michelle Denburg, and Edward Nehus. Clinical course and management of children with iga vasculitis with nephritis. Pediatric Nephrology (Berlin, Germany), 38:3721-3733, Jun 2023. URL: https://doi.org/10.1007/s00467-023-06023-8, doi:10.1007/s00467-023-06023-8. This article has 17 citations.