Abstract
The hydatid cyst is a parasitic pathology which is endemic in Tunisia and presents a public health problem.Hydatid cysts located in the retroperitoneum, especially around or in the kidney, are rare and only represent 5% of visceral locations. The kidney is the most commonly affected organ of the urinary tract.The psoas muscle is an uncommon location and not less than 70 cases have been cited. We report the Case of an unusual presentation of a right kidney hydatid cyst associated with a psoas muscle location. To our knowledge, this association of double retroperitoneal location has not been reported in the literature.