Nodular sarcoid myositis of skeletal muscle diagnosed by fine needle aspiration biopsy - A case report

BACKGROUND: Symptomatic striated muscle involvement in sarcoidosis is rare. Muscle biopsy is usually required for the diagnosis. Fine needle aspiratio n biopsy (FNAB) has been successfully used in diagnosing soft tissue lesion s. To the best of our knowledge, FNAB of sarcoid myositis has not been repo rted. CASE: A 31-year-old, black female with a history of sarcoidosis presented w ith an enlarging, painful, left calf mass. Infected thrombi were suspected. FNAB showed numerous loosely arranged epithelioid histiocytes, multinuclea ted giant cells and skeletal muscle cells. The overall cytologic picture wa s that of granulomatous myositis. The cytologic features coupled with the p atient's history and magnetic resonance imaging findings suggested sarcoid myositis. Subsequent muscle biopsy showing noncaseating granulomata and neg ative stains for organisms confirmed the diagnosis of nodular sarcoid myosi tis. CONCLUSION: Nodular sarcoid myositis can be,suggested by FNAB cytology in a patient with a past history of sarcoidosis.