The diagnosis of Poncet's disease.

Two cases of polyarthritis in young people with extra-articular tuberculosis are described. The clinical features were consistent with the concept of Poncet's disease. After synovial biopsy one patient proved to have tuberculous peripheral arthritis. This observation raised doubts about the diagnosis in the other patient. Multiple joints may be simultaneously infected with Mycobacterium tuberculosis and Poncet's disease, if it exists, should not be entertained in the absence of synovial biopsy.