ABSTRACT

Sarcoidosis is a systemic autoimmune disease characterized by non-caseating granulomatous inflammation with unknown etiology. Although the lungs and respiratory system are most commonly involved, sarcoidosis may involve virtually any part of the body, including the locomotor system. The most common rheumatological presentation of sarcoidosis may be considered as arthritis involving ankles and/or knees, frequently associated with erythema nodosum. Muscle involvement may be asymptomatic, or may cause acute or chronic myositis or nodular masses. Bone lesions tend to ocur in chronic cases having additional skin involvement. Occasionally, axial skeletal involvement, dactylitis, exocrine gland involvement or blood vessel infiltration may also occur. Therefore, sarcoidosis may sometimes mimic inflammatory myopathies, metastatic bone diseases, and spondylarthritis including psoriatic arthritis, Sjogren's syndrome or vasculitis. Presence of hyperuricemia may cause misdiagnosis of gout. Sarcoidosis generally follows a benign course with occasional spontan remissions. Histopathological features remain the gold standard in diagnosis. Level of evidence for management of sarcoidosis is low, generally reflecting the results of limited number of clinical studies, case series and expert opinion.The most commonly used agents include corticosteroids and conventional immunosuppressive agents. In selected cases, biological agents including, tumour necrosis factor inhibitors, seem to be promising. With regard to locomotor system involvement, sarcoid arthritis and myositis generally respond to treatment better, while bone lesions are commonly treatment-resistant.