Sarcoidosis is a systemic disease of unknown etiology, usually affecting the respiratory tract, skin, eyes and other organs. The diagnosis can be challenging. Clinically, sarcoidosis frequently affects young and middle-aged adults and can present with pulmonary infiltrates, hilar lymphadenopathy, as well as ocular and skin lesions. Associated laboratory findings include elevated serum angiotensin-converting enzyme, lysozyme, and calcium levels.

According to a joint statement on sarcoidosis, the diagnosis of sarcoidosis requires: 1) a compatible clinical and radiological picture; 2) histological evidence of non-necrotizing epithelioid granulomas (although necrotizing sarcoid granulomatosis has been rarely described); and 3) exclusion of other causes of granulomatous inflammation (including mycobacterial and fungal infections, hypersensitivity syndromes, drug reactions, foreign-body granulomas, and certain tumors, especially lymphomas). In this case, special stains for fungi and Acid- Fast Bacilli tests were negative. Flow cytometry showed no evidence for a lymphoma. Upon further history, the patient was known to have sarcoidosis.

See related content for references:

1) Statement on sarcoidosis. Joint Statement of the American Thoracic Society (ATS), the European Respiratory Society (ERS) and the World Association of Sarcoidosis and Other Granulomatous Disorders (WASOG) adopted by the ATS Board of Directors and by the ERS Executive Committee, February 1999.