Sarcoidosis is a multisystem disorder of unknown cause(s) that commonly affects young and middle-age adults worldwide. Its common presentations include bilateral hilar adenopathy, pulmonary infiltration, and skin and ocular lesions. There is significant variability in its clinical features and outcome among the different ethnic groups. The clinical manifestations are protean and can present in an acute, subacute, or chronic form. The clinical course is also variable from spontaneous resolution to progressive disease despite treatment. The diagnosis of sarcoidosis requires compatible clinical and radiological features and often a histologic evidence of noncaseating granuloma on biopsy of affected site. Other causes of granuloma formation and local sarcoid reactions have to be excluded. The … Source: MedWorm: Sarcoidosis