Sarcoidosis is a well-characterized systemic disease, the origin of which remains elusive despite years of intense research.

It is characterized pathologically by noncaseating epithelioid granulomas that contain giant cells. As a systemic disease, it may affect any organ system, but it commonly affects the lungs and lymph nodes.

Skin manifestations are common, and patients with hilar adenopathy and erythema nodosum alone usually have less severe disease than those with parenchymal lung involvement and other extrapulmonary manifestations. Sarcoidosis occurs most commonly in adults 20 to 40 years old and is slightly more common in women than in men. In the United States, African- Americans are more commonly affected, but the disease allergic, prevalent in Scandinavian countries. Infectious, and environmental exposures have all been proposed as triggers of the disease in patients with a genetic susceptibility, but neither genetic factors nor specific triggers have been established. Sarcoidosis has distinct immunologic features. Circulating CD4′ lymphocytes are decreased, and CD4 cells obtained from bronchoalveolar lavage are increase Findings include variable cutaneous anergy, increased concentrations of interleukin-1 and tumor necrosis factor in bronchoalveolar lavage fluid, decreased numbers of circulating B lymphocytes, and increased serum concentrations of polyclonal immunoglobulins. All these findings indicate activation of the immune system. symptoms of sarcoidosis reflect the organ systems involved. The most common presenting complaints are cough and dyspnea.

Fatigue and are common, but even high can occur on occasion. skin manifestations include erythema nodosum, plaques, common.

The Ocular symptoms are also triad of uveitis, parotitis, facial palsy, called uveoparotid fever, is known as Heerfordt’s syndrome .