Abstract
Hydatidosis is a worldwide infectious disease caused by the larval form of a parasitic tapeworm of helminths affecting mainly the liver and lungs in cattle- and sheep-raising regions. Muscle localization remains extremely rare and its diagnosis is sometimes challenging. We report the case of a 45-year-old man presenting with a swelling of the left thigh gradually increasing in size. Clinical examination was non-specific, sonographic evaluation suggested the diagnosis, and the patient underwent successful surgical treatment. Intramuscular hydatid cyst is an uncommon disease even in endemic countries, usually confused with other lesions which is a source of delayed treatment and fatal complications. MRI is the gold standard allowing diagnosis and providing the characteristic aspects which are of major importance for optimal management.