[Single ruptured pelvic hydatid cyst as an unusual manifestation of secondary peritoneal echinococcosis].

The authors report the case of a large pelvic tumour compressing the bladder, the ureters and the recto-sigmoid junction. Its sudden rupture into the peritoneum led to an emergency operation and the discovery of a hydatid cyst ruptured into the pouch of Douglas and a hepatic cyst. The most frequent presentation of peritoneal echinococcosis, peritoneal cysts are metastases from a hepatic or splenic cyst which has ruptured into the peritoneum. They are usually multiple. Single pelvic lesions are rare, their hydatid nature is in the absence of a past history of hydatid disease difficult to suspect before operation. The object of the latter is to treat in one stage the primary cyst and its peritoneal metastases. The narrow vascular connections of the pelvic cysts render cystectomy dangerous and make one prefer removal of the germinal membrane followed by marsupialisation or drainage of the remaining cavity. In the long term, the frequency of peritoneal recurrences makes prolonged supervision necessary.