Hydatid disease of the vermiform appendix

A 50-year old woman came with a six-month history of a right iliac fossa painful palpable mass. Abdominal ultrasonography and computerized tomography revealed a calcified cystic mass. At laparotomy, the cystic mass was an enlarged appendix, containing a hydatid cyst without any other organ involvement. This is a rare manifestation of this disease