Recurrent primary hydatid disease of the tibia.

Hydatid disease is caused by a cestode, Echinococcus. Its intermediate hosts are herbivores but humans can be accidental hosts. Hydatid disease is endemic in some parts of America, Australia, the Mediterranean region, Central Asia, and Central and Eastern Europe. The organs most frequently affected by Echinococcus are the liver and the lungs. Primary involvement of the skeleton is rare. Cases have been reported in the vertebrae, pelvis, humerus and femur. The location of hydatid cysts in the tibia is rarely described in the medical literature. We, herein, report a case of primary hydatid cyst of the tibia presenting with a pathologic fracture simulating benign bone cystic lesion. The diagnosis of hydatid bone disease was not suspected preoperatively. This case emphasizes the importance of considering hydatid disease in the differential diagnosis of cystic bone lesions, especially in individuals coming from regions where the disease is endemic.