Primary cystic echinococcosis in the subcutaneous gluteal region - a case report.

Cystic echinococcosis (hydatidosis, hydatid disease) belongs to the group of the most severe parasitic diseases of man and is caused by metacestodes (larvae) of Echinococcus granulosus. Dogs and other canid mammals are the definitive hosts harbouring the adult stages of the tape worm in their intestines. Proglottids containing eggs are passed in the faeces of the definitive host. The eggs are ingested by intermediate hosts (i.e. sheep, cattle, swine etc.), in which the metacestode stage develops. Humans are accidental hosts and are infected by ingestion of eggs upon contact with contaminated water, vegetables, fur (of the dogs) or contaminated hands, the subsequently developing metacestodes are usually localized in the liver, the lungs and many other organs. We report on a case of a 57 year old female patient of Turkish origin suffering from a multicystic gluteal lesion diagnosed by CT- and MRT scan. Surgical intervention revealed a subcutaneous hydatid cyst of 15 cm in diameter. Parasitological-serological examinations revealed a highly positive specific antibody level against E. granulosus arc 5 antigen. The surgically resected cysts could be identified as E. granulosus sheep strain (genotype G1). Additionally to the surgical treatment the patient received albendazole postoperatively. Primary subcutaneous cystic echinococcosis without involving thoracic or abdominal organs is extremely rare and it has not been reported so far. Since soft tissue tumors may resemble hydatid cysts, careful preoperative evaluation is critical for proper handling during surgery to avoid possible anaphylactic reactions or spillage of protoscoleces, particularly when patients are deriving from endemic areas.