Introduction
Clonorchiasis, due to Clonorchis sinensis and opisthorchiasis, due to Opisthorchis, occur in Southeast Asia and Eastern Europe
-Clonorchiasis and opisthorchiasis are clinically indistinguishable.
-Humans are infected by eating raw, pickled, frozen, dried, salted, and smoked fish containing the encysted larvae (metacercariae)
-After excystation in the duodenum, immature flukes invade the biliary ducts and differentiate into adults
Symptoms & Signs
Most infections are asymptomatic
Fever, chills, abdominal pain, urticaria, eosinophilia, hepatomegaly, cholecystitis, cholangitis, pancreatitis, liver abscess, jaundice
-Chronic infection is associated with increased risk of cholangiocarcinoma
Diagnosis
Definitive diagnosis is made by finding the typical brownish, small, operculated eggs in the stool
-The eggs of Opisthorchis are indistinguishable from those of Clonorchis
– Imaging studies: Biliary tract dilatations with filling defects due to flukes
Treatment
The drug of choice is praziquantel
Other effective agent: Albendazole