Blau syndrome
Findings
No curated finding names Blau syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Blau syndrome (BS) is a rare systemic inflammatory disease characterized by early onset granulomatous arthritis, uveitis and skin rash. BS now refers to both the familial and sporadic (formerly early-onset sarcoidosis) form of the same disease. The proposed term pediatric granulomatous arthritis is currently questioned since it fails to represent the systemic nature of the disease.
Definition from the Mondo Disease Ontology (MONDO:0008523), read 2026-09-29. CC BY 4.0.
Features
49 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Intermittent generalized erythematous papular rashHPOHP:0007432
- 42 of 44 reported patients
- ArthritisHPOHP:0001369
- 61 of 66 reported patients
- Frequent (30% to 79% of cases)
- Abnormal inflammatory responseHPOHP:0012647
- Very frequent (80% to 99% of cases)
- ArthralgiaHPOHP:0002829
- Very frequent (80% to 99% of cases)
- ErythemaHPOHP:0010783
- Very frequent (80% to 99% of cases)
- Hyperpigmentation of the skinHPOHP:0000953
- Very frequent (80% to 99% of cases)
- IridocyclitisHPOHP:0001094
- Very frequent (80% to 99% of cases)
- Joint swellingHPOHP:0001386
- Very frequent (80% to 99% of cases)
- KeratitisHPOHP:0000491
- Very frequent (80% to 99% of cases)
- Limitation of joint mobilityHPOHP:0001376
- Very frequent (80% to 99% of cases)
- PapuleHPOHP:0200034
- Very frequent (80% to 99% of cases)
- Polyarticular arthritisHPOHP:0005764
- Very frequent (80% to 99% of cases)
Show the remaining 37
- Posterior uveitisHPOHP:0012123
- Very frequent (80% to 99% of cases)
- Skin rashHPOHP:0000988
- Very frequent (80% to 99% of cases)
- SynovitisHPOHP:0100769
- Very frequent (80% to 99% of cases)
- UveitisHPOHP:0000554
- 39 of 54 reported patients
- Camptodactyly of fingerHPOHP:0100490
- Frequent (30% to 79% of cases)
- CataractHPOHP:0000518
- Frequent (30% to 79% of cases)
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- NOD2HGNC:5331
- Definitive · ClinGen · Autosomal dominant · 2020
- Definitive · Illumina · Autosomal dominant · 2020
- Definitive · G2P · Autosomal dominant · 2017
- Strong · Genomics England PanelApp · Autosomal dominant · 2020
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal dominant · 2023
- Strong · PanelApp Australia · Autosomal dominant · 2025
- Supportive · Orphanet · Autosomal dominant · 2021
Where it sits
Other names
11 names
Resolves to: Blau syndrome
- Also called
- arthrocutaneouveal granulomatosisBLAUSearly-onset sarcoidosisEOSgranulomatosis, familial juvenile systemicgranulomatosis, familial, Blau typegranulomatous inflammatory arthritis, dermatitis, and uveitis, familialJabs syndromepaediatric granulomatous arthritispediatric granulomatous arthritissarcoidosis, early-onset