Primary hydatid disease in adductor muscles.

Primary muscular Echinococcus infection is very rare without involvement of thoracic and abdominal organs. In this case a 31-year-old man who had a growing mass in the postero-medial part of his right thigh was examined. The mass was diagnosed as hydatid cyst using ultrasound, magnetic resonance imaging (MRI) and serological tests. It was removed surgically and there has been no recurrence one year after the surgery. The MRI imaging characteristics may differ depending on the life cycle stage of the parasite. In this case report, we discuss the imaging characteristics of the muscular hydatid cyst with special emphasis on the MRI findings. In regions where hydatidosis is endemic, a mass found in body muscles should be considered as a muscular hydatid cyst.