Sarcoidosis

Abstract

Sarcoidosis is a systemic disorder of unknown aetiology characterised by noncaseating granulomas leading principally to bilateral hilar lymphadenopathies, pulmonary infiltration and skin and eye lesions. Sarcoidosis may involve other organs, including peripheral lymph nodes, liver, spleen, nervous and musculoskeletal systems, heart, ear, nose and kidney. Although the clinical involvement of liver and heart is relatively uncommon, hepatic and cardiac granulomas are present at autopsy in about 70 to 80% and 25 to 50%, respectively, of patients with this disease. The diagnosis of sarcoidosis includes compatible clinical and/or radiological presentations and histological evidence of noninfectious and noncaseating epitheloid cell granulomas in the absence of other identifiable agents responsible for such histological lesions. Disease course is variable and usually characterised by frequent remissions, but it may become progressive and chronic in a small percentage of patients. The optimal treatment of sarcoidosis remains poorly defined. In patients with progressive pulmonary dysfunction as well as in those with severe extrapulmonary localisations, systemic corticosteroids usually represent the first approach, limited by long term toxicity and frequent relapses after treatment interruption. In the presence of refractory or corticosteroid-dependent forms of the disease, antimalarial drugs or low dosage methotrexate may be used with prolonged benefit. The indications for immunosuppressive agents such as azathioprine, chlorambucil, cyclophosphamide and cyclosporin are uncommon and limited because of potentially serious adverse effects and lack of information on their long term efficacy. In the case of ocular and limited cutaneous manifestations, local corticosteroid therapy may be useful.