Conditions with similar clinical presentations that must be differentiated from Acne Vulgaris:
Acne vulgaris is a chronic inflammatory disorder of the pilosebaceous unit driven by the interplay of sebaceous lipid dysregulation, follicular hyperkeratinization, Cutibacterium acnes (C. acnes) strain-level immunostimulation, and downstream innate/adaptive immune activation, modulated by androgen/IGF‑1 metabolic signaling and the cutaneous microbiome. Dysbiosis with enrichment of C. acnes phylotype IA1, altered sebum composition, and activation of TLR and inflammasome pathways converge to initiate IL‑1β–dependent comedogenesis and propagate Th17/IL‑17–skewed inflammation; chronicity can culminate in extracellular matrix (ECM) remodeling, with MMP/TGF‑β pathways contributing to scars. Clinical phenotypes span microcomedones, comedones, papules/pustules, nodules, and scarring. Prevalence is high in adolescence (≈85%) and persists in subsets such as adult female acne where androgenic drivers are prominent (15–20% prevalence among adult women; hyperandrogenism in ~50% of cases, commonly linked to PCOS). (kim2024exploringacnetreatments pages 3-4, dessinioti2024themicrobiomeand pages 3-4, amuzescu2024adultfemaleacne pages 1-2, mdermUnknownyearacnevulgarisadvancesa pages 1-2)
Where 2025 sources are cited (microbiome bibliometrics; sebaceous gland lipid review; matrix–microbiome review), they extend and reinforce 2023–2024 findings but should be interpreted with corroboration from contemporaneous primary studies. (zhang2025analysisofglobal pages 15-17, mosca2025thesebaceousgland pages 5-7)
References
(kim2024exploringacnetreatments pages 3-4): Hyun Jee Kim and Yeong Ho Kim. Exploring acne treatments: from pathophysiological mechanisms to emerging therapies. International Journal of Molecular Sciences, 25:5302, May 2024. URL: https://doi.org/10.3390/ijms25105302, doi:10.3390/ijms25105302. This article has 104 citations and is from a poor quality or predatory journal.
(dessinioti2024themicrobiomeand pages 3-4): Clio Dessinioti and Andreas Katsambas. The microbiome and acne: perspectives for treatment. Dermatology and Therapy, 14:31-44, Jan 2024. URL: https://doi.org/10.1007/s13555-023-01079-8, doi:10.1007/s13555-023-01079-8. This article has 50 citations and is from a poor quality or predatory journal.
(amuzescu2024adultfemaleacne pages 1-2): Andreea Amuzescu, Mircea Tampa, Clara Matei, and Simona Roxana Georgescu. Adult female acne: recent advances in pathophysiology and therapeutic approaches. Cosmetics, 11:74, May 2024. URL: https://doi.org/10.3390/cosmetics11030074, doi:10.3390/cosmetics11030074. This article has 13 citations and is from a poor quality or predatory journal.
(mdermUnknownyearacnevulgarisadvancesa pages 1-2): RYMDMHA Mderm and MD Baruch Kaplan. Acne vulgaris: advances in pathogenesis and innovations in therapeutic strategies. Unknown journal, Unknown year.
(mosca2025thesebaceousgland pages 5-7): Sarah Mosca, Monica Ottaviani, Stefania Briganti, Anna Di Nardo, and Enrica Flori. The sebaceous gland: a key player in the balance between homeostasis and inflammatory skin diseases. Cells, 14:747, May 2025. URL: https://doi.org/10.3390/cells14100747, doi:10.3390/cells14100747. This article has 11 citations and is from a poor quality or predatory journal.
(zhang2025analysisofglobal pages 15-17): Lanfang Zhang, Yuan Cai, Lin Li, Jie Hu, Changsha Jia, Xu Kuang, Yi Zhou, Zhiai Lan, Chunyan Liu, Feng Jiang, Nana Sun, and Ni Zeng. Analysis of global trends and hotspots of skin microbiome in acne: a bibliometric perspective. BioData Mining, Mar 2025. URL: https://doi.org/10.1186/s13040-025-00433-0, doi:10.1186/s13040-025-00433-0. This article has 3 citations and is from a peer-reviewed journal.
name: Acne Vulgaris
creation_date: '2026-01-23T23:13:39Z'
updated_date: '2026-02-16T20:19:38Z'
category: Complex
disease_term:
preferred_term: acne vulgaris
term:
id: MONDO:0011438
label: acne
parents:
- Inflammatory skin disease
- Pilosebaceous unit disorder
infectious_agent:
- name: Cutibacterium acnes
infectious_agent_term:
preferred_term: Cutibacterium acnes
term:
id: NCBITaxon:1747
label: Cutibacterium acnes
description: Commensal skin bacterium that proliferates in occluded follicles and contributes to inflammatory acne lesions.
evidence:
- reference: PMID:24062871
reference_title: "The role of inflammation in the pathology of acne."
supports: SUPPORT
snippet: "Propionibacterium acnes colonizes the duct of the sebaceous follicle, causing an innate immune response and the progression from a so-called noninflammatory comedo to an inflammatory papule, pustule, or nodule."
explanation: This review links C. acnes colonization to inflammatory progression in acne.
prevalence:
- population: Adolescents and young adults (Europe, ages 15-24 years)
percentage: 57.8
evidence:
- reference: PMID:28707712
reference_title: "Acne prevalence and associations with lifestyle: a cross-sectional online survey of adolescents/young adults in 7 European countries."
supports: SUPPORT
snippet: "The overall adjusted prevalence of self-reported acne was 57.8% (95% confidence interval 56.9% to 58.7%)."
explanation: This European survey reports a high prevalence of acne among adolescents and young adults.
- population: Adolescents and young adults (global, ages 10-24 years, 2021)
percentage: 9.79
evidence:
- reference: PMID:39271178
reference_title: "Global, regional and national burdens of acne vulgaris in adolescents and young adults aged 10-24 years from 1990 to 2021: a trend analysis."
supports: SUPPORT
snippet: |-
RESULTS: Globally, the age-standardized prevalence rate of acne vulgaris among
adolescents and young adults increased from 8563.4 per 100 000 population [95%
uncertainty interval (UI) 7343.5-9920.1] in 1990 to 9790.5 (95% UI 8420.9-11
287.2) per 100 000 population in 2021, with an AAPC of 0.43 [95% confidence
interval (CI) 0.41-0.46].
explanation: The 2021 age-standardized prevalence of 9790.5 per 100,000 corresponds to about 9.79%.
- population: Young people (moderate-to-severe acne)
percentage: 20
evidence:
- reference: PMID:23210645
reference_title: "Epidemiology of acne vulgaris."
supports: SUPPORT
snippet: "Moderate-to-severe acne affects around 20% of young people and severity correlates with pubertal maturity."
explanation: This review summarizes the prevalence of moderate-to-severe acne among young people.
pathophysiology:
- name: Follicular keratinization
description: >
Dysregulated keratinocyte differentiation and desquamation within the
follicular epithelium promotes retention hyperkeratosis.
cell_types:
- preferred_term: keratinocyte
term:
id: CL:0000312
label: keratinocyte
locations:
- preferred_term: pilosebaceous unit
term:
id: UBERON:0011932
label: pilosebaceous unit
evidence:
- reference: PMID:32748305
reference_title: "Effects of Diet on Acne and Its Response to Treatment."
supports: SUPPORT
snippet: "Acne pathogenesis is attributed to four key factors: excess sebum production, hyperproliferation of Cutibacterium acnes (C. acnes, formerly called Propionibacterium acnes) bacteria, hyperkeratinization of the pilosebaceous follicles, and inflammatory mechanisms"
explanation: This review explicitly identifies hyperkeratinization of the pilosebaceous follicles as a key factor in acne pathogenesis.
- name: Microcomedone formation
description: >
Follicular obstruction from retained keratin and sebum leads to early
microcomedone development that seeds later visible comedones.
cell_types:
- preferred_term: keratinocyte
term:
id: CL:0000312
label: keratinocyte
locations:
- preferred_term: pilosebaceous unit
term:
id: UBERON:0011932
label: pilosebaceous unit
evidence:
- reference: PMID:32748305
reference_title: "Effects of Diet on Acne and Its Response to Treatment."
supports: SUPPORT
snippet: "Acne pathogenesis is attributed to four key factors: excess sebum production, hyperproliferation of Cutibacterium acnes (C. acnes, formerly called Propionibacterium acnes) bacteria, hyperkeratinization of the pilosebaceous follicles, and inflammatory mechanisms"
explanation: Follicular hyperkeratinization is the initiating event that drives microcomedone formation in acne.
- name: Sebum overproduction
description: >
Androgen and IGF-1 signaling increase sebocyte activity, elevating sebum
output and creating a lipid-rich follicular environment.
cell_types:
- preferred_term: sebocyte
term:
id: CL:0000317
label: sebocyte
biological_processes:
- preferred_term: lipid metabolism
term:
id: GO:0006629
label: lipid metabolic process
evidence:
- reference: PMID:32748305
reference_title: "Effects of Diet on Acne and Its Response to Treatment."
supports: SUPPORT
snippet: "In acne, mTORC1 mediates sebaceous gland hyperproliferation, lipid synthesis, and hyperplasia of keratinocytes"
explanation: This review links sebaceous gland hyperproliferation and lipid synthesis to acne pathogenesis.
- name: Sebum compositional change
description: >
Altered fatty acid ratios and oxidation products within sebum contribute
to comedogenesis and inflammatory signaling.
cell_types:
- preferred_term: sebocyte
term:
id: CL:0000317
label: sebocyte
biological_processes:
- preferred_term: lipid metabolism
term:
id: GO:0006629
label: lipid metabolic process
evidence:
- reference: PMID:20871834
reference_title: "Lipid mediators in acne."
supports: SUPPORT
snippet: "Altered ratio between saturated and unsaturated fatty acids has been indicated as an important feature to be considered in addition to the altered amount of specific fatty acids such as linoleic acid"
explanation: This review highlights altered sebum fatty acid composition as a pathophysiologic feature of acne.
- name: C. acnes follicular colonization
description: >
Cutibacterium acnes expands within occluded follicles and contributes to
lesion progression from noninflammatory comedones to inflamed papules.
cell_types:
- preferred_term: sebocyte
term:
id: CL:0000317
label: sebocyte
locations:
- preferred_term: pilosebaceous unit
term:
id: UBERON:0011932
label: pilosebaceous unit
evidence:
- reference: PMID:24062871
reference_title: "The role of inflammation in the pathology of acne."
supports: SUPPORT
snippet: "Propionibacterium acnes colonizes the duct of the sebaceous follicle, causing an innate immune response and the progression from a so-called noninflammatory comedo to an inflammatory papule, pustule, or nodule."
explanation: This review describes C. acnes colonization and its role in lesion progression.
- name: Inflammasome activation
description: >
Innate immune sensing activates inflammasome pathways that amplify
inflammatory signaling in acne lesions.
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: DOI:10.3389/fimmu.2023.1075834
supports: PARTIAL
snippet: "The inflammasomes are intracellular multimeric protein complexes consisting of an innate immune sensor, the adapter protein ASC and the inflammatory caspases-1 and/or -11 and are important for the host defense against pathogens."
explanation: This review explains inflammasome activation, a key mechanism implicated in acne inflammation.
- name: Cytokine-driven inflammation
description: >
Inflammasome and innate immune activation drive cytokine release that
recruits neutrophils and sustains inflammatory lesion formation.
cell_types:
- preferred_term: neutrophil
term:
id: CL:0000775
label: neutrophil
biological_processes:
- preferred_term: inflammatory response
term:
id: GO:0006954
label: inflammatory response
evidence:
- reference: DOI:10.3389/fimmu.2023.1075834
supports: PARTIAL
snippet: "The inflammasomes are intracellular multimeric protein complexes consisting of an innate immune sensor, the adapter protein ASC and the inflammatory caspases-1 and/or -11 and are important for the host defense against pathogens."
explanation: Inflammasome activation supports downstream cytokine-mediated inflammation in acne lesions.
phenotypes:
- name: Comedones
description: >
Non-inflammatory lesions including open comedones (blackheads) and closed
comedones (whiteheads) resulting from follicular plugging.
phenotype_term:
preferred_term: comedonal acne
term:
id: HP:0040137
label: Comedonal acne
evidence:
- reference: PMID:24062871
reference_title: "The role of inflammation in the pathology of acne."
supports: SUPPORT
snippet: "evidence has emerged supporting a role for inflammation at all stages of acne lesion development, perhaps subclinically even before comedo formation"
explanation: This review discusses the role of comedones as a key lesion type in acne pathogenesis.
- name: Inflammatory papules
description: >
Small, raised, erythematous lesions resulting from inflammation around
occluded follicles.
phenotype_term:
preferred_term: erythematous papule
term:
id: HP:0030350
label: Erythematous papule
evidence:
- reference: PMID:24062871
reference_title: "The role of inflammation in the pathology of acne."
supports: SUPPORT
snippet: "the progression from a so-called noninflammatory comedo to an inflammatory papule, pustule, or nodule"
explanation: This review describes the progression from comedones to inflammatory papules in acne lesion development.
- name: Pustules
description: >
Inflamed lesions containing purulent material, representing more advanced
inflammatory response.
phenotype_term:
preferred_term: pustule
term:
id: HP:0200039
label: Pustule
evidence:
- reference: PMID:12113648
reference_title: "Pustular skin disorders: diagnosis and treatment."
supports: SUPPORT
snippet: "Localized pustular eruptions are seen on the hands and feet in adults with pustulosis palmaris et plantaris and acrodermatitis continua (both of which may be variants of psoriasis); on the face in patients with acne vulgaris, rosacea, and perioral dermatitis"
explanation: This review identifies pustular eruptions on the face as a characteristic feature of acne vulgaris.
- name: Nodules and cysts
description: >
Deep, painful lesions representing severe inflammatory acne with potential
for scarring.
phenotype_term:
preferred_term: cystic acne
term:
id: HP:0033188
label: Cystic acne
evidence:
- reference: PMID:21062102
reference_title: "Therapeutic considerations for severe nodular acne."
supports: SUPPORT
snippet: "Severe nodular acne, defined as grade 4 or 5 acne on the Investigator's Static Global Assessment scale, is a skin condition characterized by intense erythema, inflammation, nodules, cysts, and scarring."
explanation: This review defines severe nodular acne as characterized by nodules and cysts with associated inflammation and scarring potential.
- name: Post-inflammatory hyperpigmentation
description: >
Darkening of skin at sites of resolved acne lesions, particularly common
in individuals with darker skin tones. This sequela results from inflammatory
damage to melanocytes and is a common concern in patients with skin of color.
phenotype_term:
preferred_term: hyperpigmentation of the skin
term:
id: HP:0000953
label: Hyperpigmentation of the skin
evidence:
- reference: PMID:34468934
reference_title: "The Pathogenesis and Management of Acne-Induced Post-inflammatory Hyperpigmentation."
supports: SUPPORT
snippet: "the inflammatory processes of acne stimulate excess melanogenesis and abnormal melanin deposition, leading to pigmentary sequelae known as post-inflammatory hyperpigmentation"
explanation: This paper specifically describes the pathogenesis of acne-induced post-inflammatory hyperpigmentation through excess melanin production.
- name: Scarring
description: >
Permanent textural changes including atrophic (ice pick, boxcar, rolling)
and hypertrophic scars resulting from severe or inadequately treated acne.
phenotype_term:
preferred_term: atrophic scars
term:
id: HP:0001075
label: Atrophic scars
evidence:
- reference: PMID:29344322
reference_title: "Acne Scarring-Pathogenesis, Evaluation, and Treatment Options."
supports: SUPPORT
snippet: "This review focuses on atrophic scars, the most common type of acne scar."
explanation: This review confirms atrophic scars as the most common type of acne scarring.
biochemical:
- name: Androgens
presence: Elevated
notes: >
Androgens (testosterone, DHT) stimulate sebaceous gland activity through
androgen receptor signaling, explaining the onset of acne at puberty and
its association with hyperandrogenic states.
evidence:
- reference: PMID:32748305
reference_title: "Effects of Diet on Acne and Its Response to Treatment."
supports: SUPPORT
snippet: "Excess sebum production occurs because of increased activity of androgen hormones and IGF-1"
explanation: This paper directly links androgen hormones to excess sebum production in acne pathogenesis.
- name: Sebum lipids
presence: Altered
notes: >
Changes in sebum composition, including altered fatty acid profiles and
increased squalene oxidation, contribute to comedogenesis and inflammation.
evidence:
- reference: PMID:20871834
reference_title: "Lipid mediators in acne."
supports: SUPPORT
snippet: "Altered ratio between saturated and unsaturated fatty acids has been indicated as an important feature to be considered in addition to the altered amount of specific fatty acids such as linoleic acid"
explanation: This review describes alterations in sebum fatty acid composition as a key feature in acne pathogenesis.
- name: IL-17
presence: Decreased
notes: >
Serum IL-17 levels are lower in acne vulgaris compared with controls in a
severity-stratified cohort, suggesting altered systemic cytokine signaling.
evidence:
- reference: PMID:41465543
reference_title: "Assessment of Serum and Saliva CRP, IL-17, and IL-19 Levels in Patients with Different Severity of Acne Vulgaris."
supports: SUPPORT
snippet: "Serum IL-17 levels were significantly higher in the control group compared to both acne groups (p < 0.05), with no gender-related differences."
explanation: This study reports decreased serum IL-17 in acne vulgaris compared with controls.
genetic:
- name: Polygenic susceptibility
association: Associated
notes: >
Twin studies demonstrate high heritability. Multiple genetic variants
affecting androgen metabolism, inflammatory pathways, and sebaceous gland
function contribute to acne susceptibility.
evidence:
- reference: PMID:32748305
reference_title: "Effects of Diet on Acne and Its Response to Treatment."
supports: SUPPORT
snippet: "It is known that multiple factors impact acne pathophysiology, including genetic, hormonal, inflammatory, and environmental influences."
explanation: This review explicitly identifies genetic factors as one of the key influences on acne pathophysiology.
- reference: PMID:40689430
reference_title: "The Genetics of Acne."
supports: SUPPORT
snippet: "Both GWAS and single gene disorders unequivocally indicate stem/progenitor cell maintenance and cellular migration as the most important processes in the pathogenesis of acne."
explanation: This genetics review connects GWAS and monogenic findings to core biological processes underlying acne susceptibility.
- name: Candidate gene families
association: Associated
notes: >
Reviews highlight inflammatory cytokine genes (IL, TNF), RETN, CYP family
genes, and extracellular matrix regulators (MMPs, TIMPs) as recurrent
candidates linked to acne susceptibility.
evidence:
- reference: PMID:37662507
reference_title: "Genetic Variants Associated with Acne Vulgaris."
supports: SUPPORT
snippet: "some genes (such as IL, TNF, RETN, CYP family, MMPs and TIMPs genes et al) are associated with acne vulgaris and may affect the progression and prognosis of the disease."
explanation: This review summarizes multiple gene families repeatedly implicated in acne susceptibility and outcomes.
- name: RETN-420C>G and IL6-572G>C polymorphisms
association: Associated
notes: >
Case-control data in a Chinese cohort link RETN-420G and IL6-572C alleles
to increased acne susceptibility and severity.
evidence:
- reference: PMID:35279931
reference_title: "Influence of RETN, IL-1, and IL-6 gene polymorphisms on the risk of acne vulgaris in the Chinese population."
supports: SUPPORT
snippet: "There is a strong correlation between RETN-420 and IL6-572 polymorphisms and acne susceptibility; the RETN-420G and IL6-572C alleles increase the risk of acne development."
explanation: This study reports RETN-420 and IL6-572 risk alleles associated with acne susceptibility.
- name: TNFR2 M196R and TLR2 Arg753Gln polymorphisms
association: Associated
notes: >
Risk alleles in TNFR2 and TLR2 are enriched in moderate-to-severe acne
subgroups, supporting an inflammatory genetic contribution.
evidence:
- reference: PMID:20861605
reference_title: "Association study of tumor necrosis factor receptor type 2 M196R and toll-like receptor 2 Arg753Gln polymorphisms with acne vulgaris in a Chinese Han ethnic group."
supports: SUPPORT
snippet: "The 196R allele of TNFR2 M196R as well as the 753Gln allele of TLR2 Arg753Gln are risk factors for acne vulgaris in Chinese Han patients, further supporting the contribution of inflammatory cytokines to the pathogenesis of acne."
explanation: This study links TNFR2 and TLR2 risk alleles to acne susceptibility in a Chinese Han cohort.
environmental:
- name: Diet
description: >
High glycemic index foods and dairy products have been associated with
acne severity, possibly through effects on insulin/IGF-1 signaling and
hormonal modulation.
evidence:
- reference: PMID:32748305
reference_title: "Effects of Diet on Acne and Its Response to Treatment."
supports: SUPPORT
snippet: "Several studies have evaluated the significance of the glycemic index of various foods and glycemic load in patients with acne, demonstrating individuals with acne who consume diets with a low glycemic load have reduced acne lesions compared with individuals on high glycemic load diets."
explanation: This review provides evidence for the association between high glycemic load diets and acne severity.
- reference: PMID:32748305
reference_title: "Effects of Diet on Acne and Its Response to Treatment."
supports: SUPPORT
snippet: "Dairy has also been a focus of study regarding dietary influences on acne; whey proteins responsible for the insulinotropic effects of milk may contribute more to acne development than the actual fat or dairy content."
explanation: The paper describes the mechanism by which dairy consumption may influence acne through insulinotropic effects.
- name: Stress
description: >
Psychological stress can exacerbate acne through effects on the
hypothalamic-pituitary-adrenal axis and increased sebum production.
evidence:
- reference: PMID:28871928
reference_title: "The Impact of Pyschological Stress on Acne."
supports: SUPPORT
snippet: "Even though emotional stress has long been suspected to trigger or exacerbate acne, its influence on acne severity has been mostly underestimated until recently when studies have brought new data about the different mechanisms and possible factors involved in this interaction."
explanation: This review examines the link between psychological stress and acne exacerbation.
- reference: PMID:28871928
reference_title: "The Impact of Pyschological Stress on Acne."
supports: SUPPORT
snippet: "The basis for the association between emotional stress and the onset or exacerbation of acne is in several cutaneous neurogenic factors which interact with a pathogenic cascade in acne."
explanation: The paper describes neurogenic mechanisms linking stress to acne pathogenesis.
- name: Air pollution and climate stressors
description: >
Repeated exposure to rising pollutant levels and climate-related
environmental changes is associated with acne burden.
evidence:
- reference: PMID:41464454
reference_title: "The Environmental Determinants of Skin Health: Linking Climate Change, Air Pollution, and the Dermatologic Disease Burden."
supports: SUPPORT
snippet: "Psoriasis, acne vulgaris, atopic dermatitis, photoaging, melasma, and skin cancers have been associated with repeated exposure to rising levels of pollutants."
explanation: This review links acne vulgaris with pollutant exposure among climate-sensitive skin conditions.
datasets:
- accession: geo:GSE315350
title: Microbiome-Derived Indole-3-lactic Acid Attenuates Cutibacterium acnes-Induced Inflammation via the Aryl Hydrocarbon Receptor Pathway
description: >-
Transcriptomic profiling of C. acnes-driven inflammation with microbiome-
derived tryptophan metabolites highlighting AHR pathway modulation.
notes: Summary describes human keratinocyte stimulation and a C. acnes mouse model.
- accession: geo:GSE301280
title: Spatial transcriptomics reveals dysfunctional lipid metabolism and abnormal pilosebaceous differentiation in acne vulgaris
description: >-
Spatial transcriptomics of healthy, non-lesional, comedonal, and pustular
acne skin using a panel targeting sebaceous differentiation, lipid
metabolism, and retinoid signaling.
organism:
preferred_term: human
term:
id: NCBITaxon:9606
label: Homo sapiens
data_type: SPATIAL_TRANSCRIPTOMICS
conditions:
- healthy skin
- non-lesional acne skin
- comedonal acne skin
- pustular acne skin
notes: Identifies altered sebogenesis and retinoid signaling across lesion types.
- accession: geo:GSE292394
title: High-Resolution Spatial Map of the Human Facial Sebaceous Gland Reveals Marker Genes and Decodes Sebocyte Differentiation [MERFISH]
description: >-
Spatial transcriptomics and MERFISH profiling of human facial sebaceous
glands to map sebocyte differentiation stages.
organism:
preferred_term: human
term:
id: NCBITaxon:9606
label: Homo sapiens
data_type: SPATIAL_TRANSCRIPTOMICS
notes: Integrates spatial transcriptomics with single-cell profiling of sebaceous glands.
treatments:
- name: Topical retinoids
description: >
First-line treatment that normalizes follicular keratinization, reduces
comedone formation, and has anti-inflammatory effects. Examples include
tretinoin, adapalene, and tazarotene.
treatment_term:
preferred_term: retinoid agent therapy
term:
id: MAXO:0000237
label: retinoid agent therapy
qualifiers:
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: retinoid
term:
id: NCIT:C68299
label: Retinoid
evidence:
- reference: PMID:30674002
reference_title: "Topical Retinoids in Acne Vulgaris: A Systematic Review."
supports: SUPPORT
snippet: "Topical retinoids are safe and efficacious for the treatment of acne vulgaris."
explanation: This systematic review confirms the safety and efficacy of topical retinoids for acne treatment.
- name: Trifarotene
description: >
Topical retinoid selective for retinoic acid receptor gamma with evidence
for reducing comedonal and inflammatory lesions, including truncal acne.
treatment_term:
preferred_term: retinoid agent therapy
term:
id: MAXO:0000237
label: retinoid agent therapy
qualifiers:
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: trifarotene
term:
id: NCIT:C118577
label: Trifarotene
evidence:
- reference: PMID:36927117
reference_title: "Management of Acne Vulgaris With Trifarotene."
supports: SUPPORT
snippet: "Large-scale randomized, controlled clinical trials have demonstrated trifarotene to be safe, well tolerated, and efficacious in reducing both comedones and papules/pustules of acne."
explanation: This review summarizes randomized trials showing trifarotene efficacy across comedonal and inflammatory acne lesions.
- name: Benzoyl peroxide
description: >
Antimicrobial agent that kills C. acnes through oxidative damage without
promoting antibiotic resistance. Also has mild comedolytic activity.
treatment_term:
preferred_term: antimicrobial agent therapy
term:
id: MAXO:0001021
label: antimicrobial agent therapy
qualifiers:
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: benzoyl peroxide
term:
id: NCIT:C47411
label: Benzoyl Peroxide
evidence:
- reference: PMID:19761357
reference_title: "Benzoyl peroxide: a review of its current use in the treatment of acne vulgaris."
supports: SUPPORT
snippet: "BPO-containing combinations do not induce bacterial resistance and are important first-line treatments for mild to moderate acne vulgaris."
explanation: This review establishes benzoyl peroxide as an important first-line treatment for acne that does not promote bacterial resistance.
- name: Topical antibiotics
description: >
Clindamycin and erythromycin reduce C. acnes populations and have
anti-inflammatory effects. Should be combined with benzoyl peroxide to
prevent resistance.
treatment_term:
preferred_term: antibacterial agent therapy
term:
id: MAXO:0000061
label: antibacterial agent therapy
qualifiers:
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: antibiotic
term:
id: NCIT:C258
label: Antibiotic
evidence:
- reference: PMID:16086756
reference_title: "Treatment of acne with topical antibiotics: lessons from clinical studies."
supports: SUPPORT
snippet: "topical antibiotics remain one of the cornerstones of acne management"
explanation: This systematic review confirms topical antibiotics as a cornerstone treatment for acne.
- name: Clindamycin/adapalene/benzoyl peroxide gel
description: >
Triple-combination topical therapy for moderate to severe acne, combining
clindamycin phosphate, adapalene, and benzoyl peroxide for long-term use.
treatment_term:
preferred_term: pharmacotherapy
term:
id: MAXO:0000058
label: pharmacotherapy
qualifiers:
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: clindamycin phosphate
term:
id: NCIT:C47978
label: Clindamycin Phosphate
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: adapalene
term:
id: NCIT:C28989
label: Adapalene
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: benzoyl peroxide
term:
id: NCIT:C47411
label: Benzoyl Peroxide
evidence:
- reference: PMID:41552868
reference_title: "Long-term efficacy and tolerability of clindamycin phosphate 1.2%/adapalene 0.15%/benzoyl peroxide 3.1% gel for acne: pooled results from two 6-month studies."
supports: SUPPORT
snippet: "At week 24, 67% of participants achieved treatment success, and significant reductions from baseline in inflammatory (88%) and noninflammatory (68%) lesions were observed (p < 0.001, both)."
explanation: This pooled analysis supports long-term efficacy of the triple-combination gel.
- name: Oral antibiotics
description: >
Tetracyclines (doxycycline, minocycline) are used for moderate-to-severe
inflammatory acne. Have both antimicrobial and anti-inflammatory effects,
but prolonged use contributes to antimicrobial resistance and requires
stewardship.
treatment_term:
preferred_term: antibacterial agent therapy
term:
id: MAXO:0000061
label: antibacterial agent therapy
qualifiers:
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: tetracycline antibiotic
term:
id: NCIT:C1595
label: Tetracycline Antibiotic
evidence:
- reference: PMID:28542914
reference_title: "Efficacy and adverse events of oral isotretinoin for acne: a systematic review."
supports: SUPPORT
snippet: "isotretinoin therapy reduced acne lesion counts by a clinically relevant amount, and always by a greater amount than control, which was either placebo (two studies), oral antibiotics (seven studies) or other control"
explanation: This systematic review confirms oral antibiotics as an established comparator treatment for acne in clinical trials.
- reference: PMID:36568833
reference_title: "Antibiotics and Antimicrobial Resistance in Acne: Epidemiological Trends and Clinical Practice Considerations."
supports: SUPPORT
snippet: "The overuse of topical and/or systemic antibiotics, the long treatment courses used for acne, and the availability of over-the-counter antibiotic preparations, have led to the worldwide emergence of resistant strains in acne patients."
explanation: This review documents antibiotic resistance concerns tied to prolonged acne antibiotic use, supporting stewardship in treatment.
- name: Oral isotretinoin
description: >
Systemic retinoid reserved for severe, recalcitrant acne. Addresses all
four pathogenic factors but requires careful monitoring due to
teratogenicity and other adverse effects.
treatment_term:
preferred_term: retinoid agent therapy
term:
id: MAXO:0000237
label: retinoid agent therapy
qualifiers:
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: isotretinoin
term:
id: NCIT:C603
label: Isotretinoin
evidence:
- reference: PMID:33085149
reference_title: "Systematic review of low-dose isotretinoin for treatment of acne vulgaris: Focus on indication, dosage, regimen, efficacy, safety, satisfaction, and follow up, based on clinical studies."
supports: SUPPORT
snippet: "Oral isotretinoin is the most effective treatment for moderate to severe acne and its side effects are mostly dose-dependent."
explanation: This systematic review confirms oral isotretinoin as the most effective treatment for moderate to severe acne.
- name: Hormonal therapy
description: >
Combined oral contraceptives and spironolactone reduce androgen effects
on sebaceous glands. Used in female patients with hormonal acne patterns.
treatment_term:
preferred_term: hormone modifying therapy
term:
id: MAXO:0000283
label: hormone modifying therapy
qualifiers:
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: oral contraceptive
term:
id: NCIT:C389
label: Oral Contraceptive
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: spironolactone
term:
id: NCIT:C840
label: Spironolactone
evidence:
- reference: PMID:28492054
reference_title: "A Review of hormone-based therapies to treat adult acne vulgaris in women."
supports: SUPPORT
snippet: "Hormone-based therapies including combined oral contraceptive medications and spironolactone are considered effective therapies to treat adult acne in women."
explanation: This systematic review confirms the efficacy of hormonal therapies including oral contraceptives and spironolactone for treating acne in women.
- name: Chemical peels
description: >
Organic acid-based peels are used to exfoliate acne-prone skin and reduce
lesion counts, with agent selection tailored to patient tolerability.
treatment_term:
preferred_term: therapeutic procedure of skin of body
term:
id: MAXO:0001417
label: therapeutic procedure of skin of body
qualifiers:
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: chemical peel
term:
id: NCIT:C93203
label: Chemical Peel
evidence:
- reference: PMID:37894698
reference_title: "A Comprehensive Bibliographic Review Concerning the Efficacy of Organic Acids for Chemical Peels Treating Acne Vulgaris."
supports: SUPPORT
snippet: "The findings of this comprehensive bibliographic review indicate that organic acid-based chemical peels represent effective and safe treatment options for individuals with acne-prone skin."
explanation: This review supports organic acid chemical peels as effective and safe adjuncts for acne-prone skin.
- name: Azelaic acid peel
description: >
Azelaic acid peels reduce sebum and lesion burden as a nonpharmacologic
option for facial acne.
treatment_term:
preferred_term: therapeutic procedure of skin of body
term:
id: MAXO:0001417
label: therapeutic procedure of skin of body
qualifiers:
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: chemical peel
term:
id: NCIT:C93203
label: Chemical Peel
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: azelaic acid
term:
id: NCIT:C47407
label: Azelaic Acid
evidence:
- reference: PMID:31455112
reference_title: "Efficacy of 30% azelaic acid peel in the nonpharmacological treatment of facial acne."
supports: SUPPORT
snippet: "Peels with 30% AZA reduced acne lesions and normalized the activity of the sebaceous glands."
explanation: This study reports acne lesion reduction and sebum normalization with 30% azelaic acid peels.
- name: Chemical peels for acne scarring
description: >
Medium-depth peels such as glycolic acid and trichloroacetic acid are
used to improve atrophic acne scars.
treatment_term:
preferred_term: therapeutic procedure of skin of body
term:
id: MAXO:0001417
label: therapeutic procedure of skin of body
qualifiers:
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: chemical peel
term:
id: NCIT:C93203
label: Chemical Peel
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: glycolic acid
term:
id: NCIT:C83737
label: Glycolic Acid
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: topical trichloroacetic acid
term:
id: NCIT:C125002
label: Topical Trichloroacetic Acid
evidence:
- reference: PMID:39483653
reference_title: "A comparative study of 70% glycolic acid and 30% trichloroacetic acid peel in the treatment of facial atrophic acne scars: A split-face study."
supports: SUPPORT
snippet: "A 30% TCA peel is efficacious and well-tolerated for mild-to-moderate acne scars."
explanation: This split-face study supports TCA peels for improving acne scarring.
- name: Ablative fractional CO2 laser
description: >
Ablative fractional CO2 laser is used for atrophic acne scars but can
cause erythema, dyspigmentation, and prolonged recovery.
treatment_term:
preferred_term: laser surgical procedure
term:
id: MAXO:0001578
label: laser surgical procedure
qualifiers:
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: laser therapy
term:
id: NCIT:C15466
label: Laser Therapy
evidence:
- reference: PMID:41521693
reference_title: "Reparative Effects of a Topical Antioxidant Serum Containing Vitamin C, Vitamin E, and Ferulic Acid After Ablative Fractional CO(2) Laser Treatment for Atrophic Acne Scars: A Randomized, Investigator-Blinded, Split-Face, Controlled Trial."
supports: SUPPORT
snippet: "Ablative fractional CO2 laser is effective for acne scar treatment but is often associated with side effects such as erythema and dyspigmentation, along with prolonged recovery time."
explanation: This trial background notes efficacy of CO2 laser for acne scars with notable side effects.
- name: Post-laser antioxidant serum
description: >
Topical antioxidant serum with vitamins C and E (with ferulic acid) is
used after ablative laser procedures to support skin recovery.
treatment_term:
preferred_term: pharmacotherapy
term:
id: MAXO:0000058
label: pharmacotherapy
qualifiers:
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: vitamin C
term:
id: NCIT:C68507
label: Vitamin C
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: topical vitamin E
term:
id: NCIT:C67081
label: Topical Vitamin E
evidence:
- reference: PMID:41521693
reference_title: "Reparative Effects of a Topical Antioxidant Serum Containing Vitamin C, Vitamin E, and Ferulic Acid After Ablative Fractional CO(2) Laser Treatment for Atrophic Acne Scars: A Randomized, Investigator-Blinded, Split-Face, Controlled Trial."
supports: SUPPORT
snippet: "This study found that CE Ferulic led to enhanced wound healing, reduced erythema and melanin levels, and improved skin hydration following laser treatment, suggesting its beneficial application in combination with laser treatment to accelerate skin recovery."
explanation: This split-face trial supports antioxidant serum use after CO2 laser for acne scars.
- name: Blue light therapy
description: >
Blue light phototherapy is used as an alternative for inflammatory acne,
with evidence of clinical improvement.
treatment_term:
preferred_term: radiation therapy
term:
id: MAXO:0000014
label: radiation therapy
qualifiers:
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: phototherapy
term:
id: NCIT:C15301
label: Phototherapy
evidence:
- reference: PMID:34696155
reference_title: "Effect of Blue Light on Acne Vulgaris: A Systematic Review."
supports: SUPPORT
snippet: "Studies have shown significant improvements in the overall picture of acne."
explanation: This systematic review reports clinical improvement in acne with blue light phototherapy.
- name: Visible light therapy
description: >
Visible light devices, including blue light, can reduce acne lesion
counts in patients seeking nonpharmacologic treatments.
treatment_term:
preferred_term: radiation therapy
term:
id: MAXO:0000014
label: radiation therapy
qualifiers:
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: phototherapy
term:
id: NCIT:C15301
label: Phototherapy
evidence:
- reference: PMID:39056372
reference_title: "Visible Light in the Treatment of Acne Vulgaris."
supports: SUPPORT
snippet: "Overall, 92% of patients achieved partial remission of their acne lesions using visible light therapy."
explanation: This systematic review summarizes lesion improvement across visible light studies in acne.
- name: Photodynamic therapy
description: >
Photodynamic therapy is used off-label for inflammatory acne with
evidence supporting efficacy in dermatologic indications.
treatment_term:
preferred_term: radiation therapy
term:
id: MAXO:0000014
label: radiation therapy
qualifiers:
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: photodynamic therapy
term:
id: NCIT:C15300
label: Photodynamic Therapy
evidence:
- reference: PMID:39226531
reference_title: "Photodynamic therapy in dermatology: established and new indications."
supports: SUPPORT
snippet: "Newer indications, for which no approval has yet been granted, but which nevertheless have sufficient evidence of efficacy according to the study situation, are inflammatory (lichen sclerosus, acne) and infectious dermatoses (viral warts, cutaneous leishmaniasis, atypical mycobacteriosis)."
explanation: This review identifies acne as an emerging indication for photodynamic therapy with supportive evidence.
- name: Nd:YAG laser and intralesional PRP
description: >
Nd:YAG laser and intralesional platelet-rich plasma injections are used
for inflammatory acne in split-face comparative protocols.
treatment_term:
preferred_term: therapeutic procedure of skin of body
term:
id: MAXO:0001417
label: therapeutic procedure of skin of body
qualifiers:
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: laser therapy
term:
id: NCIT:C15466
label: Laser Therapy
- predicate:
preferred_term: therapeutic agent
term:
id: NCIT:C2259
label: Therapeutic Agent
value:
preferred_term: platelet-rich plasma
term:
id: NCIT:C106557
label: Platelet-rich Plasma
evidence:
- reference: PMID:35084634
reference_title: "Clinical evaluation of efficacy of intralesional platelet-rich plasma injection versus 1064 nm long-pulsed Neodymium:YAG laser in the treatment of inflammatory acne vulgaris in adolescent and post-adolescent patients: a prospective randomized split-face comparative study."
supports: SUPPORT
snippet: "The intralesional PRP injection and 1064 nm long-pulsed Nd:YAG laser are safe and effective methods for controlling inflammatory as well as non-inflammatory acne vulgaris in both adolescents and post-adolescent patients."
explanation: This randomized split-face study supports Nd:YAG laser and PRP injections for inflammatory acne vulgaris.
- name: 1726 nm laser therapy
description: >
Targeted laser therapy that selectively affects sebaceous glands and is
being evaluated for moderate to severe acne.
treatment_term:
preferred_term: laser surgical procedure
term:
id: MAXO:0001578
label: laser surgical procedure
qualifiers:
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: laser therapy
term:
id: NCIT:C15466
label: Laser Therapy
- predicate:
preferred_term: therapeutic procedure
term:
id: NCIT:C49236
label: Therapeutic Procedure
value:
preferred_term: infrared laser therapy
term:
id: NCIT:C66918
label: Infrared Laser Therapy
evidence:
- reference: PMID:38271552
reference_title: "1726 nm Lasers for the Treatment of Acne Vulgaris."
supports: SUPPORT
snippet: "New 1726 nm lasers specifically target the sebaceous gland, which is known to be pivotal in acne pathophysiology."
explanation: This review highlights 1726 nm lasers as a sebaceous gland-targeted treatment approach for acne.
clinical_trials:
- name: NCT00421993
phase: PHASE_III
status: COMPLETED
description: Multicenter, randomized, double-blind trial comparing adapalene/benzoyl peroxide gel with monotherapies and vehicle in acne vulgaris over 12 weeks.
target_phenotypes:
- preferred_term: comedonal acne
term:
id: HP:0040137
label: Comedonal acne
- preferred_term: erythematous papule
term:
id: HP:0030350
label: Erythematous papule
- preferred_term: pustule
term:
id: HP:0200039
label: Pustule
evidence:
- reference: clinicaltrials:NCT00421993
supports: SUPPORT
snippet: "This is a multi-center, randomized, double-blind, parallel group study with 12 weeks of treatment of acne vulgaris."
explanation: The trial evaluates a combination topical therapy specifically in participants with acne vulgaris.
- name: NCT02249767
phase: PHASE_III
status: COMPLETED
description: Double-blind, randomized, parallel-group study assessing tretinoin gel bioequivalence in patients with mild acne vulgaris.
target_phenotypes:
- preferred_term: comedonal acne
term:
id: HP:0040137
label: Comedonal acne
- preferred_term: erythematous papule
term:
id: HP:0030350
label: Erythematous papule
evidence:
- reference: clinicaltrials:NCT02249767
supports: SUPPORT
snippet: "Normal, healthy male and female children and adults (i.e., ages 12 to 40 years) with at least Grade 2 (i.e., mild severity) acne vulgaris were treated on the full face once daily for 84 days with the Tretinoin Gel 0.05%, Brand (tretinoin) Gel 0.05%, or Gel Vehicle."
explanation: This study explicitly enrolls participants with acne vulgaris and evaluates topical tretinoin treatment.
differential_diagnoses:
- name: PAPASH syndrome
disease_term:
preferred_term: PAPASH syndrome
term:
id: MONDO:0958343
label: PAPASH syndrome
description: >
Autoinflammatory syndrome combining acne with pyoderma gangrenosum,
hidradenitis suppurativa, and inflammatory arthritis.
distinguishing_features:
- Syndromic triad with pyoderma gangrenosum and hidradenitis suppurativa alongside acne.
- Systemic inflammatory arthritis or other autoinflammatory features.
evidence:
- reference: PMID:41499625
reference_title: "PAPASH Syndrome: A Case Report and Lessons for Clinical Practice."
supports: SUPPORT
snippet: "PAPASH spectrum syndrome is a rare autoinflammatory condition encompassing psoriatic arthritis, pyoderma gangrenosum, acne, and hidradenitis suppurativa."
explanation: This case report defines PAPASH syndrome as a syndromic condition including acne and related inflammatory diseases.
- name: Rosacea
disease_term:
preferred_term: rosacea
term:
id: MONDO:0006604
label: rosacea
description: >
Chronic inflammatory facial dermatosis with papules and pustules but no comedones. Central facial erythema, flushing,
and telangiectasias can mimic inflammatory acne on the face.
distinguishing_features:
- Absence of comedones with prominent centrofacial erythema and telangiectasias.
- Burning or stinging with triggers such as heat, alcohol, or spicy foods rather than androgen-driven distribution.
evidence:
- reference: PMID:12113648
reference_title: "Pustular skin disorders: diagnosis and treatment."
supports: SUPPORT
snippet: "Localized pustular eruptions are seen on the hands and feet in adults with pustulosis palmaris et plantaris and acrodermatitis continua (both of which may be variants of psoriasis); on the face in patients with acne vulgaris, rosacea, and perioral dermatitis; and on the trunk and/or extremities in patients with folliculitis."
explanation: The abstract lists rosacea alongside acne as a facial pustular eruption, underscoring the need for clinical differentiation.
- name: Bacterial folliculitis
disease_term:
preferred_term: folliculitis
term:
id: MONDO:0006552
label: folliculitis
description: >
Infection or inflammation of hair follicles producing papules and pustules on hair-bearing skin, often the trunk or extremities,
that can resemble acne lesions but lacks comedones and is frequently pruritic.
distinguishing_features:
- Lesions centered on hair follicles without open or closed comedones; often pruritic and may follow shaving or occlusion.
- Distribution favors trunk, buttocks, and extremities rather than the typical facial and truncal comedones of acne.
evidence:
- reference: PMID:12113648
reference_title: "Pustular skin disorders: diagnosis and treatment."
supports: SUPPORT
snippet: "Localized pustular eruptions are seen on the hands and feet in adults with pustulosis palmaris et plantaris and acrodermatitis continua (both of which may be variants of psoriasis); on the face in patients with acne vulgaris, rosacea, and perioral dermatitis; and on the trunk and/or extremities in patients with folliculitis."
explanation: The abstract notes folliculitis presents with pustular eruptions on the trunk or extremities, highlighting its overlap with acneiform lesions.