SARCOIDOSIS

Sarcoidosis is a systemic granulomatous process of unknown cause. Path ologically, it is characterized by noncaseous granuloma, and in more t han 90% of patients, the lung or intrathoracic lymph nodes are affecte d. A roentgenographic staging system (stages I, II, and III), based on the appearance of the plain chest roentgenogram, conveys important in formation about prognosis, degree of symptoms, and pulmonary function abnormalities. The diagnosis should be confirmed by histopathologic ex amination and exclusion of known causes for the noncaseous granulomato us reaction. When indicated, treatment with alternate-day regimens of prednisone is highly effective. Serial chest roentgenography, pulmonar y function studies, and the serum angiotensin-converting enzyme level are useful for monitoring the course of the disease.