Hydatid Disease - Echinococcus Granulosus Infection

Abstract

A 60-year-old Turkish woman presented with a rapidly growing cystic enlargement of the liver. Ultrasound at admission revealed multiple liver cysts without calcifications. Magnetic resonance imaging (MRI) was performed to evaluate resectability. Transversal and coronal T1- and -weighted MRI through the level of the lesion demonstrated a septate cystic mass with multiple large “daughter cysts” within a well-defined fibrous capsule (18.6×12.5×18 cm). A strong mass effect upon adjacent structures was apparent. Measurement of antibodies specific for Echinococcus granulosus confirmed the diagnosis of hydatid disease (ELISA: E. granulosus EIA positive, echinococcus IHA 1:400). The patient was treated with albendazole (10 mg/kg body mass) for 4 weeks and a total of two cycles with a 2-week break between. However, operation was refused and the patient left Germany for a pilgrimage to Mecca, Saudi Arabia. Differential diagnosis of echinococcosis and polycystic liver cysts based on MRI imaging may be difficult and is not possible based on the thickness of the cyst wall. Cysts with different densities may suggest hydatid disease rich in accumulated scolices but do not allow differentiation from bleeding into a cyst - which may reveal similar findings. The only pathognomonic signs, which allow a differential diagnosis based on MR imaging between polycystic liver cysts and hydatid disease (Echinococcus granulosus) are daughter cysts, which are demonstrable within a larger cyst.