A long-term follow-up of Japanese mother and her daughter with Blau syndrome: Effective treatment of anti-TNF inhibitors and useful diagnostic tool of joint ultrasound examination.

Blau syndrome (BS) is an autosomal dominant autoinflammatory disease associated with NOD2 gene mutations. It is characterized by arthritis, skin rash, and uveitis. Here, we report contrasting outcomes of a daughter and her mother with BS. Their long-term follow-up revealed the efficacy of anti-tumor necrosis factor inhibitor (TNF) with respect to BS. Joint findings of BS feature tenosynovitis over articular synovitis on ultrasonography. BS might be one of the differential diagnoses of juvenile idiopathic arthritis and rheumatoid arthritis.