Sarcoidosis is a multi-system granulomatous diseases of undetermined etiology characterized by activation of lymphocytes and mononuclear phagocytes at the site of the disease (1). Seen most often between 30-40 years of age, it can effect any race, though less common in tropics. It involves lungs in 80-90% of cases (2), although it is a multi-organ disease and can present to any of the medical or surgical discipline (3). In areas endemic for Tuberculosis like Pakistan there may be lot of difficulty in excluding Mycobacterial infection, since both the diseases have similar clinico-radiological, biochemical and pathological features (4). Clinical and epidemiological features favor the hypothesis that it results from environmental exposure, possibly infectioe agents. An updated review of the subject is presented.