Blau syndrome (MONDO_0008523, a Monarch Disease Ontology id) (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. Also known as: BLAUS, EOS, Jabs syndrome, arthrocutaneouveal granulomatosis, early-onset sarcoidosis, granulomatosis, familial juvenile systemic, granulomatosis, familial, Blau type, granulomatous inflammatory arthritis, dermatitis, and uveitis, familial.