Sarcoidosis of the skin: a review for the pulmonologist.

With vastly heterogeneous morphologic manifestations, sarcoidosis is one of the "great imitators" of medicine. Because there is no specific confirmatory test, the diagnosis rests on clinical acumen coupled with supportive information from tissue or blood evaluation and the exclusion of other diseases. The characteristic histologic pattern of noncaseating, epithelioid cell granulomas is not always present in skin lesions, which may be visually distinctive or diverse in appearance. As a result of their high incidence of respiratory disease, patients with sarcoidosis frequently seek care from pulmonologists who may become their primary health-care providers. Physicians who treat patients with sarcoidosis should be aware of the disease's diverse organ manifestations, but particularly those appearing on the skin because these can be disfiguring, have prognostic importance, and may not be readily diagnosed even by skin specialists. In this comprehensive review, we sought to illustrate this diversity and to update the diagnostic approach, histologic spectrum, and therapeutic strategies involved in cutaneous sarcoidosis.