A family with a syndrome consisting of granulomatous arthritis, uveitis, and rash was first described in 1985. Another family with the same syndrome was described subsequently in 1990. The condition, in both families, is clinically different from sarcoidosis. To verify whether the granulomas in such patients also could be distinctive, we performed histologic, ultrastructural, and immunocytochemical studies on skin and synovial biopsy specimens from a child under our care who suffered from the same syndrome. The results indicated that the granulomas could not be distinguished from those seen in sarcoidosis either by light microscopy or by immunocytochemical studies. However, by electron microscopy, "wormlike" or "comma-shaped" bodies were noted within the cytoplasm of epithelioid cells. The significance of this observation is discussed.