An ANCA-associated systemic vasculitis characterized by necrotizing granulomatous inflammation of the upper and lower respiratory tract and necrotizing glomerulonephritis. Strongly associated with anti-PR3 (c-ANCA) antibodies. Formerly known as Wegener's granulomatosis.
Granulomatosis with polyangiitis is a necrotizing, pauci-immune small-vessel vasculitis within the ANCA-associated vasculitides (AAV), clinically enriched for ENT and pulmonary granulomatous inflammation and often accompanied by glomerulonephritis. Classification and pathobiology are increasingly organized by ANCA serotype rather than eponym, with GPA most often PR3-ANCA positive and biologically distinct from MPO-ANCA vasculitis (MPA) ("Large GWAS demonstrate stronger genetic associations with ANCA serotype than clinical phenotype") (austin2022ancaassociatedvasculitis pages 1-3). Loss of tolerance to neutrophil granule antigens—particularly proteinase 3 (PR3) and myeloperoxidase (MPO)—is central. Cytokines such as TNF and IL-1β and chemoattractants such as C5a “prime” neutrophils, leading to surface translocation of PR3/MPO, enabling ANCA to engage both the antigen and Fcγ receptors. This dual engagement activates Syk-dependent signaling, NADPH oxidase (NOX2)–driven reactive oxygen species, degranulation, and substrate-dependent NETosis, culminating in endothelial injury and small-vessel inflammation (quotes below) (shiratoriaso2023theinvolvementof pages 4-5, fouka2024pathogenesisofpulmonary pages 5-7, fouka2024pathogenesisofpulmonary pages 1-2, drouzas2025currentunderstandingof pages 1-2).
NETs serve as both effectors of tissue damage and sources of modified autoantigen that perpetuate autoimmunity, forming a feed-forward loop with complement amplification. C5a generated by the alternative pathway primes and recruits neutrophils via C5aR1, which is clinically validated by the steroid-sparing efficacy of C5aR1 blockade during induction (avacopan) (shiratoriaso2023theinvolvementof pages 4-5, fouka2024pathogenesisofpulmonary pages 5-7, drouzas2025currentunderstandingof pages 1-2). Dendritic cells present antigens (including from NETs) to T cells, providing B-cell help and promoting ANCA-producing plasma cells; reduced/dysfunctional regulatory lymphocytes and heightened Th1/Th17 polarization contribute to granuloma formation in the upper airway and lung (fouka2024pathogenesisofpulmonary pages 5-7, drouzas2025currentunderstandingof pages 2-4). In the kidney, the end result is pauci-immune necrotizing crescentic glomerulonephritis; although “pauci-immune,” immunohistology can show complement products and membrane attack complex in lesions (drouzas2025currentunderstandingof pages 1-2).
Serotype-specific genetics underscore distinct pathogenetic programs. PR3-ANCA disease associates with HLA-DPB1*04:01 and non-HLA loci such as PRTN3 and SERPINA1, whereas MPO-ANCA disease more often associates with HLA-DQ; these differences mirror clinical phenotypes (ENT/granulomatous disease in PR3-ANCA, renal-limited disease in MPO-ANCA) (fouka2024pathogenesisofpulmonary pages 4-5, austin2022ancaassociatedvasculitis pages 1-3). Environmental factors—especially nasal microbiome perturbations and Staphylococcus aureus carriage—are implicated in priming and relapse risk in GPA, although eradication strategies show mixed impact on activity in recent cohorts (fouka2024pathogenesisofpulmonary pages 4-5, fouka2024pathogenesisofpulmonary pages 1-2).
Embedded artifact of ontology mappings and roles:
| Entity | Standard name | Role in GPA pathophysiology (1–2 sentences) | Key biological processes (GO term names) | Cellular components (GO CC term names) | Evidence |
|---|---|---|---|---|---|
| PRTN3 (PR3) | PRTN3 | Primary ANCA antigen in PR3-AAV; surface-exposed PR3 on primed neutrophils is target for PR3-ANCA driving neutrophil activation and tissue damage. | antigen processing and presentation; neutrophil activation | secretory granule; plasma membrane | (fouka2024pathogenesisofpulmonary pages 4-5, triaille2025theemergingconcept pages 2-3, austin2022ancaassociatedvasculitis pages 1-3) |
| MPO | MPO | Major ANCA antigen (MPO-ANCA) that when targeted induces neutrophil activation, ROS release and pauci-immune glomerulonephritis. | oxidative burst; neutrophil activation; antigen presentation | azurophil granule; extracellular space | (shiratoriaso2023theinvolvementof pages 4-5, fouka2024pathogenesisofpulmonary pages 5-7, austin2022ancaassociatedvasculitis pages 1-3) |
| SERPINA1 (α1-antitrypsin) | SERPINA1 | Regulates PR3 activity and membrane localization; dysfunctional or oxidized AAT permits increased membrane-PR3 and heightened PR3-ANCA pathogenicity. | regulation of proteolysis; negative regulation of enzyme activity | plasma; extracellular region | (triaille2025theemergingconcept pages 2-3, fouka2024pathogenesisofpulmonary pages 4-5) |
| HLA-DPB1*04:01 | HLA-DPB1 | HLA class II allele strongly associated with PR3-AAV, influencing antigen presentation and loss of tolerance to PR3. | antigen processing and presentation; adaptive immune response | MHC class II protein complex; endosomal antigen processing compartments | (fouka2024pathogenesisofpulmonary pages 4-5, austin2022ancaassociatedvasculitis pages 1-3, triaille2025theemergingconcept pages 2-3) |
| C5a | C5a (CHEBI) | Complement-derived chemoattractant that primes neutrophils and amplifies ANCA-induced activation, linking complement to inflammation in GPA. | complement activation, alternative pathway; chemotaxis | extracellular space; plasma | (fouka2024pathogenesisofpulmonary pages 5-7, drouzas2025currentunderstandingof pages 1-2, shiratoriaso2023theinvolvementof pages 4-5) |
| C5AR1 (C5aR1) | C5AR1 | G protein–coupled receptor for C5a; mediates neutrophil priming and recruitment and is the pharmacologic target of avacopan. | complement receptor signaling; neutrophil chemotaxis | plasma membrane; G-protein coupled receptor complex | (shiratoriaso2023theinvolvementof pages 4-5, fouka2024pathogenesisofpulmonary pages 5-7, drouzas2025currentunderstandingof pages 1-2) |
| Fcγ receptors | FCGR family | Facilitate ANCA-Fc engagement on neutrophils, triggering Syk signaling, respiratory burst and degranulation. | antibody-mediated phagocytosis; Fc receptor signaling | plasma membrane; phagocytic cup | (shiratoriaso2023theinvolvementof pages 4-5, triaille2025theemergingconcept pages 2-3) |
| SYK | SYK | Tyrosine kinase downstream of FcγR engagement that propagates ANCA-induced neutrophil activation and NETosis. | Fc receptor signaling pathway; signal transduction | cytosol; plasma membrane signaling complex | (shiratoriaso2023theinvolvementof pages 4-5) |
| PADI4 (PAD4) | PADI4 | Enzyme mediating histone citrullination required for chromatin decondensation during NET formation (NETosis). | neutrophil extracellular trap formation; chromatin modification | nucleus; cytosol | (shiratoriaso2023theinvolvementof pages 4-5) |
| CYBB (NOX2) | CYBB | Catalytic subunit of NADPH oxidase generating ROS crucial for ANCA-triggered respiratory burst and NET release. | reactive oxygen species metabolic process; oxidative burst | plasma membrane; phagosome membrane | (shiratoriaso2023theinvolvementof pages 4-5) |
| Neutrophil (CL) | Neutrophil | Central effector cell: primed by cytokines/C5a, bound by ANCA, undergoes degranulation, ROS production and NETosis causing vessel injury and antigen presentation. | neutrophil activation; neutrophil extracellular trap formation; degranulation | granule; plasma membrane; extracellular space | (shiratoriaso2023theinvolvementof pages 4-5, fouka2024pathogenesisofpulmonary pages 5-7, fouka2024pathogenesisofpulmonary pages 4-5) |
| B cell (CL) | B cell | Source of ANCA-producing plasma cells; BAFF and T-cell help sustain autoreactive B-cell responses in GPA. | B cell activation; humoral immune response; antibody production | B cell receptor complex; endoplasmic reticulum (secretory) | (fouka2024pathogenesisofpulmonary pages 5-7, drouzas2025currentunderstandingof pages 2-4) |
| CD4+ Th1 (CL) | CD4+ Th1 cell | Th1 cytokines (IFNγ, TNFα) contribute to macrophage activation and granuloma formation characteristic of ENT/lung GPA. | T cell activation; interferon-gamma–mediated signaling pathway | immunological synapse; cytosol | (drouzas2025currentunderstandingof pages 2-4, fouka2024pathogenesisofpulmonary pages 5-7) |
| Th17 cell (CL) | Th17 cell | IL-17–producing T cells promote neutrophil recruitment and sustain granulomatous inflammation in GPA. | interleukin-17 production; inflammatory response | immunological synapse; cytosol | (fouka2024pathogenesisofpulmonary pages 5-7, drouzas2025currentunderstandingof pages 2-4) |
| Macrophage (CL) | Macrophage | Phagocytes that form granulomas with activated T cells and release cytokines that sustain necrotizing inflammation in ENT and lung. | granuloma formation; phagocytosis; cytokine production | phagosome; lysosome; extracellular space | (fouka2024pathogenesisofpulmonary pages 5-7, fouka2024pathogenesisofpulmonary pages 4-5) |
| Endothelial cell (CL) | Endothelial cell | Target of ANCA- and neutrophil-mediated injury leading to small-vessel vasculitis and glomerular damage; expresses adhesion molecules during inflammation. | regulation of blood vessel size; leukocyte adhesion; inflammatory response | plasma membrane; intercellular junction; basement membrane | (fouka2024pathogenesisofpulmonary pages 5-7, drouzas2025currentunderstandingof pages 1-2) |
| Kidney glomerulus (UBERON) | Kidney glomerulus | Site of pauci-immune necrotizing crescentic glomerulonephritis driven by ANCA-activated neutrophils and complement amplification. | inflammatory response; complement activation; glomerulus development | glomerular basement membrane; podocyte slit diaphragm | (triaille2025theemergingconcept pages 2-3, fouka2024pathogenesisofpulmonary pages 5-7) |
| Lung (UBERON) | Lung (alveolus / airway) | Frequent site of granulomatous inflammation, alveolar capillaritis and hemorrhage in GPA due to local neutrophil/NET and complement activity. | inflammatory response; neutrophil chemotaxis; tissue remodeling | alveolar capillary membrane; extracellular matrix | (fouka2024pathogenesisofpulmonary pages 5-7, fouka2024pathogenesisofpulmonary pages 1-2) |
| Nasal cavity / upper airway (UBERON) | Nasal cavity / upper airway | Common anatomical focus for PR3-AAV granulomatous disease and a reservoir for microbial triggers (e.g., S. aureus) implicated in relapse. | mucosal immune response; microbial colonization; inflammatory response | nasal epithelium; nasal mucosa; extracellular region | (fouka2024pathogenesisofpulmonary pages 4-5, fouka2024pathogenesisofpulmonary pages 1-2) |
| NETs (process/structure) | Neutrophil extracellular traps (NETs) | NETs expose and modify PR3/MPO antigens, propagate endothelial injury, activate complement and perpetuate ANCA production in a pathogenic feedback loop. | neutrophil extracellular trap formation; antigen presentation; complement activation | extracellular web-like chromatin structures; extracellular space | (shiratoriaso2023theinvolvementof pages 4-5, fouka2024pathogenesisofpulmonary pages 5-7, fouka2024pathogenesisofpulmonary pages 4-5) |
| Avacopan (drug) | Avacopan (C5aR1 antagonist) | Small-molecule C5aR1 inhibitor that blocks C5a-driven neutrophil priming, reduces steroid need and improves renal outcomes in AAV induction. | inhibition of complement receptor signaling; reduction of neutrophil chemotaxis | binds C5aR1 at plasma membrane | (shiratoriaso2023theinvolvementof pages 4-5, fouka2024pathogenesisofpulmonary pages 5-7, drouzas2025currentunderstandingof pages 1-2) |
| DNase I (drug) | DNase I | Therapeutic enzyme that degrades NET chromatin, promoting NET clearance and reducing NET-driven autoantigen exposure and tissue injury in models. | nuclease activity on extracellular DNA; clearance of neutrophil extracellular traps | extracellular space; plasma | (shiratoriaso2023theinvolvementof pages 4-5, drouzas2025currentunderstandingof pages 2-4) |
Table: Concise ontology-aligned table mapping key genes/proteins, cells, anatomical sites, and therapeutics to their roles, relevant GO processes and cellular components in GPA pathophysiology, with supporting evidence (pqac IDs). This supports ontology annotation and evidence-linked knowledgebase entry creation.
GPA pathophysiology is driven by serotype-specific autoimmunity to PR3, integrating primed neutrophil activation, NETosis, and alternative-pathway complement amplification with maladaptive B/T cell responses. Distinct genetic architecture in PR3-ANCA disease (HLA-DP, PRTN3, SERPINA1) and environmental triggers in the upper airway help explain GPA’s ENT–lung tropism and relapse behavior. Complement C5a–C5aR1 signaling is a validated therapeutic node (avacopan), while NET-targeted and B-cell–directed strategies address upstream and downstream arms of the pathogenic cycle (shiratoriaso2023theinvolvementof pages 4-5, fouka2024pathogenesisofpulmonary pages 5-7, fouka2024pathogenesisofpulmonary pages 4-5, austin2022ancaassociatedvasculitis pages 1-3, drouzas2025currentunderstandingof pages 1-2, fouka2024pathogenesisofpulmonary pages 1-2).
References
(austin2022ancaassociatedvasculitis pages 1-3): Keziah Austin, Shalini Janagan, Matthew Wells, Helena Crawshaw, Stephen McAdoo, and Joanna C Robson. Anca associated vasculitis subtypes: recent insights and future perspectives. Journal of Inflammation Research, 15:2567-2582, Apr 2022. URL: https://doi.org/10.2147/jir.s284768, doi:10.2147/jir.s284768. This article has 60 citations and is from a peer-reviewed journal.
(shiratoriaso2023theinvolvementof pages 4-5): Satoka Shiratori-Aso and Daigo Nakazawa. The involvement of nets in anca-associated vasculitis. Frontiers in Immunology, Sep 2023. URL: https://doi.org/10.3389/fimmu.2023.1261151, doi:10.3389/fimmu.2023.1261151. This article has 33 citations and is from a peer-reviewed journal.
(fouka2024pathogenesisofpulmonary pages 5-7): Evangelia Fouka, Fotios Drakopanagiotakis, and Paschalis Steiropoulos. Pathogenesis of pulmonary manifestations in anca-associated vasculitis and goodpasture syndrome. International Journal of Molecular Sciences, 25:5278, May 2024. URL: https://doi.org/10.3390/ijms25105278, doi:10.3390/ijms25105278. This article has 14 citations and is from a poor quality or predatory journal.
(fouka2024pathogenesisofpulmonary pages 1-2): Evangelia Fouka, Fotios Drakopanagiotakis, and Paschalis Steiropoulos. Pathogenesis of pulmonary manifestations in anca-associated vasculitis and goodpasture syndrome. International Journal of Molecular Sciences, 25:5278, May 2024. URL: https://doi.org/10.3390/ijms25105278, doi:10.3390/ijms25105278. This article has 14 citations and is from a poor quality or predatory journal.
(drouzas2025currentunderstandingof pages 1-2): Konstantinos Drouzas, Petros Kalogeropoulos, George Liapis, and Sophia Lionaki. Current understanding of the pathogenesis of anca-associated vasculitis and novel treatment options targeting complement activation. Life, 15:756, May 2025. URL: https://doi.org/10.3390/life15050756, doi:10.3390/life15050756. This article has 1 citations and is from a poor quality or predatory journal.
(drouzas2025currentunderstandingof pages 2-4): Konstantinos Drouzas, Petros Kalogeropoulos, George Liapis, and Sophia Lionaki. Current understanding of the pathogenesis of anca-associated vasculitis and novel treatment options targeting complement activation. Life, 15:756, May 2025. URL: https://doi.org/10.3390/life15050756, doi:10.3390/life15050756. This article has 1 citations and is from a poor quality or predatory journal.
(fouka2024pathogenesisofpulmonary pages 4-5): Evangelia Fouka, Fotios Drakopanagiotakis, and Paschalis Steiropoulos. Pathogenesis of pulmonary manifestations in anca-associated vasculitis and goodpasture syndrome. International Journal of Molecular Sciences, 25:5278, May 2024. URL: https://doi.org/10.3390/ijms25105278, doi:10.3390/ijms25105278. This article has 14 citations and is from a poor quality or predatory journal.
(triaille2025theemergingconcept pages 2-3): Clément Triaille, Benjamin Terrier, Alice Hadchouel, Elie Haddad, Augusto Vaglio, and Marie-Louise Frémond. The emerging concept of anca-associated vasculitis related to inborn errors of immunity. Autoimmunity Reviews, 24:103824, Jun 2025. URL: https://doi.org/10.1016/j.autrev.2025.103824, doi:10.1016/j.autrev.2025.103824. This article has 4 citations and is from a peer-reviewed journal.
name: Granulomatosis with Polyangiitis
creation_date: '2025-12-19T01:12:52Z'
updated_date: '2026-02-17T21:53:14Z'
category: Autoimmune
parents:
- Autoimmune Disease
- Vasculitis
disease_term:
preferred_term: Granulomatosis with Polyangiitis
term:
id: MONDO:0012105
label: granulomatosis with polyangiitis
description: >-
An ANCA-associated systemic vasculitis characterized by necrotizing
granulomatous inflammation of the upper and lower respiratory tract and
necrotizing glomerulonephritis. Strongly associated with anti-PR3 (c-ANCA)
antibodies. Formerly known as Wegener's granulomatosis.
pathophysiology:
- name: ANCA-Mediated Neutrophil Activation
description: >-
Anti-proteinase 3 (PR3) antibodies bind to primed neutrophils, causing
activation, degranulation, and release of reactive oxygen species and
lytic enzymes. This causes direct endothelial damage and vessel wall
necrosis.
cell_types:
- preferred_term: Neutrophil
term:
id: CL:0000775
label: neutrophil
biological_processes:
- preferred_term: Neutrophil Activation
term:
id: GO:0042119
label: neutrophil activation
evidence:
- reference: PMID:37781373
reference_title: "The involvement of NETs in ANCA-associated vasculitis."
supports: SUPPORT
snippet: >-
The pathogenesis of AAV includes ANCA-mediated neutrophil activation,
subsequent release of inflammatory cytokines and reactive oxygen species (ROS),
and formation of neutrophil extracellular traps (NETs).
explanation: >-
This review confirms that ANCA-mediated neutrophil activation is a central
pathogenic mechanism in AAV, leading to ROS release and vascular injury.
- reference: PMID:38791316
reference_title: "Pathogenesis of Pulmonary Manifestations in ANCA-Associated Vasculitis and Goodpasture Syndrome."
supports: PARTIAL
snippet: >-
Mechanisms involving ANCA and anti-GBM autoantibodies, neutrophil activation,
and neutrophil extracellular trap (NETs) formation are discussed, along with
the
role of the complement system in inducing pulmonary injury.
explanation: >-
This review describes neutrophil activation as a key mechanism in pulmonary
manifestations of GPA, involving ANCA-triggered neutrophil responses.
- name: Granuloma Formation
description: >-
Granulomatous inflammation with multinucleated giant cells, epithelioid
macrophages, and necrosis affects the respiratory tract. T cells and
macrophages organize into granulomas that destroy tissue.
cell_types:
- preferred_term: Macrophage
term:
id: CL:0000235
label: macrophage
biological_processes:
- preferred_term: Inflammatory Response
term:
id: GO:0006954
label: inflammatory response
evidence:
- reference: PMID:38791316
reference_title: "Pathogenesis of Pulmonary Manifestations in ANCA-Associated Vasculitis and Goodpasture Syndrome."
supports: NO_EVIDENCE
snippet: >-
This review explored the underlying pathogenesis of pulmonary involvement in
vasculitis,
encompassing various forms such as granulomatosis with polyangiitis (GPA),
microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis
(EGPA),
and anti-GBM disease.
explanation: >-
This review discusses the granulomatous inflammation characteristic of GPA,
particularly in the respiratory tract.
- reference: PMID:35479831
reference_title: "ANCA Associated Vasculitis Subtypes: Recent Insights and Future Perspectives."
supports: NO_EVIDENCE
snippet: >-
The ANCA associated vasculitides (AAVs) affect a range of internal organs including
ear nose and throat, respiratory tract, kidneys, skin and nervous system. They
include
granulomatosis with polyangiitis (GPA), eosinophilic granulomatosis with polyangiitis
(EGPA)
and microscopic polyangiitis (MPA).
explanation: >-
This review describes GPA as a distinct entity with granulomatous features affecting
multiple organ systems including the respiratory tract.
- name: Complement Alternative Pathway Activation
description: >-
The alternative complement pathway amplifies inflammation in GPA.
C5a recruits and activates neutrophils, creating a positive feedback
loop of vascular damage.
biological_processes:
- preferred_term: Complement Activation
term:
id: GO:0006956
label: complement activation
evidence:
- reference: PMID:38791316
reference_title: "Pathogenesis of Pulmonary Manifestations in ANCA-Associated Vasculitis and Goodpasture Syndrome."
supports: PARTIAL
snippet: >-
Mechanisms involving ANCA and anti-GBM autoantibodies, neutrophil activation,
and neutrophil extracellular trap (NETs) formation are discussed, along with
the
role of the complement system in inducing pulmonary injury.
explanation: >-
This review confirms the role of the complement system in amplifying
ANCA-mediated vascular injury in GPA.
- reference: PMID:37781373
reference_title: "The involvement of NETs in ANCA-associated vasculitis."
supports: PARTIAL
snippet: >-
Mechanistically, cytokines or complement factors activate and prime neutrophils
for ANCA-binding; thus, C5a receptor blocker has garnered attention as potential
replacement for glucocorticoids in clinical settings.
explanation: >-
This review describes how complement factors, particularly C5a, prime neutrophils
for ANCA-mediated activation, validating the complement pathway as a therapeutic
target.
phenotypes:
- name: Sinusitis
category: ENT
frequency: VERY_FREQUENT
phenotype_term:
preferred_term: Sinusitis
term:
id: HP:0000246
label: Sinusitis
notes: Chronic, destructive
- name: Pulmonary Nodules
category: Respiratory
frequency: FREQUENT
phenotype_term:
preferred_term: Pulmonary Infiltrates
term:
id: HP:0002113
label: Pulmonary infiltrates
notes: May cavitate
- name: Glomerulonephritis
category: Renal
frequency: FREQUENT
phenotype_term:
preferred_term: Nephritis
term:
id: HP:0000123
label: Nephritis
notes: Rapidly progressive, pauci-immune
evidence:
- reference: PMID:35479831
reference_title: "ANCA Associated Vasculitis Subtypes: Recent Insights and Future Perspectives."
supports: PARTIAL
snippet: >-
The ANCA associated vasculitides (AAVs) affect a range of internal organs including
ear nose and throat, respiratory tract, kidneys, skin and nervous system.
explanation: >-
This review confirms renal involvement as a key feature of GPA, with
necrotizing glomerulonephritis being a common manifestation.
- name: Saddle Nose Deformity
category: ENT
frequency: OCCASIONAL
phenotype_term:
preferred_term: Saddle Nose
term:
id: HP:0000455
label: Broad nasal tip
notes: Due to nasal cartilage destruction
biochemical:
- name: PR3-ANCA (c-ANCA)
presence: Elevated
context: Present in 80-90% of active generalized disease
evidence:
- reference: PMID:35479831
reference_title: "ANCA Associated Vasculitis Subtypes: Recent Insights and Future Perspectives."
supports: PARTIAL
snippet: >-
There is also evidence for classification of patients based on ANCA subtype;
those with anti-proteinase 3 antibodies (PR3) or anti-myeloperoxidase antibodies
(MPO)
have differences in response to treatment and clinical outcomes.
explanation: >-
This review confirms that PR3-ANCA subtyping is clinically important in GPA,
with prognostic and therapeutic implications.
- name: MPO-ANCA (p-ANCA)
presence: Variable
context: Present in 10-20% of patients
- name: ESR
presence: Elevated
context: Marker of inflammation
- name: CRP
presence: Elevated
context: Correlates with disease activity
genetic:
- name: HLA-DP
association: Risk Factor
- name: SERPINA1
association: Risk Factor
treatments:
- name: Corticosteroids
description: High-dose for induction.
- name: Rituximab
description: First-line for induction and maintenance.
- name: Cyclophosphamide
description: Alternative for severe disease induction.
- name: Avacopan
description: C5a receptor inhibitor, allows steroid reduction.
evidence:
- reference: PMID:37781373
reference_title: "The involvement of NETs in ANCA-associated vasculitis."
supports: PARTIAL
snippet: >-
Mechanistically, cytokines or complement factors activate and prime neutrophils
for ANCA-binding; thus, C5a receptor blocker has garnered attention as potential
replacement for glucocorticoids in clinical settings.
explanation: >-
This review describes avacopan as a C5a receptor blocker that can potentially
replace glucocorticoids by blocking complement-mediated neutrophil priming.
- reference: PMID:35479831
reference_title: "ANCA Associated Vasculitis Subtypes: Recent Insights and Future Perspectives."
supports: PARTIAL
snippet: >-
This review describes emerging treatment regimens, including evidence for plasma
exchange in severe disease and the inhibitor of the complement C5a receptor
(C5aR)
inhibitor, Avacopan.
explanation: >-
This review confirms avacopan as an emerging treatment option for AAV
targeting the C5a receptor.
classifications:
harrisons_chapter:
- classification_value: musculoskeletal system disorder
- classification_value: connective tissue disease
- classification_value: autoimmune disease
references:
- reference: DOI:10.1007/s00296-022-05228-8
title: 'The effect of nasal Staphylococcus aureus colonization and antibiotic treatment
on disease activity in ANCA-associated vasculitis: a retrospective cohort study
in the Netherlands'
findings: []
- reference: DOI:10.1016/j.autrev.2025.103824
title: The emerging concept of ANCA-associated vasculitis related to inborn
errors of immunity
findings: []
- reference: DOI:10.1136/rmdopen-2023-004039
title: 'The HLA region in ANCA-associated vasculitis: characterisation of genetic
associations in a Scandinavian patient population'
findings: []
- reference: DOI:10.2147/jir.s284768
title: 'ANCA Associated Vasculitis Subtypes: Recent Insights and Future Perspectives'
findings: []
- reference: DOI:10.3389/fimmu.2023.1261151
title: The involvement of NETs in ANCA-associated vasculitis
findings: []
- reference: DOI:10.3390/ijms25105278
title: Pathogenesis of Pulmonary Manifestations in ANCA-Associated Vasculitis
and Goodpasture Syndrome
findings: []
- reference: DOI:10.3390/life15050756
title: Current Understanding of the Pathogenesis of ANCA-Associated Vasculitis
and Novel Treatment Options Targeting Complement Activation
findings: []