Acute Appendicitis Caused by an Echinococcal Brood Capsule Unmasks an Asymptomatic Hepatic Hydatid Cyst.

Hydatidosis is an endemic helminthic disease in the cattle-grazing regions of Asia. It is usually caused by the cestode Echinococcus granulosus. Internal organs, particularly the liver and lungs, are predominantly affected, but the appendix is only rarely involved with the formation of characteristic hydatid cyst. We present a unique case of appendiceal hydatidosis in an 18-year-old woman with acute appendicitis. Her preoperative abdominal ultrasound revealed an asymptomatic hydatid cyst in the liver. An echinococcal brood capsule was detected postoperatively within the appendicular lumen under microscope.