Hydatid cysts in muscles: clinical manifestations, diagnosis, and management of this atypical presentation

Introduction: Hydatid cysts are rarely detected in muscle tissue (0.7-0.9%), even in endemic countries. The aim of this study was to present information regarding the clinical manifestations, diagnosis, and management of muscle echinococcosis. Methods: Twenty-two patients with hydatid cysts in the muscle were followed from January 2006 through December 2014. Results: Twenty-four sites of muscle involvement were observed in the 22 patients. Fifteen (68%) of our patients were women, while seven (32%) were men. The mean age was 28.1 +/- 15.4 (6-61) years. The most frequent locations were the thigh (27.2%) and the paravertebral region (13.6%). Most patients reported a painless slow-growing mass with normal overlying skin. Most (90.2%) cases were treated by surgical excision and fine-needle aspiration. Conclusions: Primary muscle hydatid cyst should be considered in the differential diagnosis in cystic masses of the muscular system without pain and localized enlargement of soft tissue, especially in endemic areas. Hydatid cyst should be investigated using serological tests and imaging modalities. If possible, total surgical excision of hydatid cyst in the muscle should be performed.