A 12-year-old girl presented with uveitis, joint disease and ichthyosis resembling ichthyosis vulgaris. A biopsy taken from the affected lower leg demonstrated sarcoidal-type granulomas. Synovial biopsy from the knee also showed granulomas. There was a family history of similar clinical features in the patient's younger sister. There were no other systemic features present to suggest a diagnosis of sarcoidosis or other granulomatous disease such as Crohn's disease or tuberculosis. The familial nature of the condition also made these diagnoses less likely. A clinical diagnosis of Blau syndrome was made. Blau syndrome is an uncommon sarcoidosis-like multisystem autosomal-dominant granulomatous disorder caused by mutations in the CARD15 gene. This gene has also recently been found to be a factor in the development of psoriatic arthritis and Crohn's disease. Although many forms of skin involvement have been described in Blau syndrome, this is the first case described of ichthyosis as the primary skin manifestation.