[Primary extensive hydatidosis of the thigh: unusual radiological aspects]

Soft tissue involvement by hydatid disease remains unusual (5%) even in endemic areas. Patients typically present late because disease progression is slow and often asymptomatic. The authors report the unusual imaging appearance in a 59 year old woman with a one year history of progressive diffuse painless swelling of the left thigh. Ultrasonography showed multiple anechoic and hypoechoic cystic lesions, some of which containing serpentine echogenic structures consistent with partly calcified membranes. CT and MRI confirmed a diagnosis of hydatid disease and were helpful to demonstrate the relationship between cysts and adjacent structures. Surgical management was performed early because of fistulization to the skin.