[Bone hydatid cyst: a rare localization at the level of the hip bone].

Hydatid disease is a parasitic disease caused by the development in humans of the larval form of a tapeworm, namely a very small tænia called Echinococcus Granulosus. This anthropozoonosis is characterized by the presence of different types of anatomo-radiologic variants associated with various topographic and evolutionary aspects of the cysts. Bone hydatid disease is a rare condition, it accounts for only 0.9-2.5% of all locations. We report the case of a 9 year old child, who was admitted with febrile lameness and with a mass in the right iliac fossa, revealing a hydatid cyst at the level of the hip bone. Lesion assessment objectified a hydatid cyst of the hip bone with extension into adjacent soft tissues. An infected cyst was detected during surgery, hence the performance of a surgical excision of the cyst with drainage. Hydatic osteopathy is infiltrating, diffuse, slow and gradual, causing delays in diagnosis and compromising the quality of care.