Sarcoidosis: still a mystery?

Sarcoidosis is a systemic granulomatous disease of unknown etiology. It has diverse clinical manifestations, most frequently including pulmonary disorders. It is associated with immunological abnormalities, the intricacies of which have yet to be clearly delineated. In the immunologically susceptible individual, genetic, environmental, nutritional, and socioeconomic factors may play a governing role in its development. Sarcoidosis is a diagnosis of exclusion established by clinical manifestations, radiologic findings, and histologic evidence of noncaseating epithelioid-cell granulomas in >1 organ. We will discuss parameters that are helpful in making this diagnosis.