Clonorchiasis is infection with the liver fluke Clonorchis sinensis. Infection is acquired by eating undercooked freshwater fish. Symptoms include fever, chills, epigastric pain, tender hepatomegaly, diarrhea, and mild jaundice. Humans become infected by eating raw, undercooked, dried, salted, or pickled fish containing encysted metacercariae. Metacercariae are released in the duodenum, enter the common bile duct through the ampulla of Vater, and migrate to smaller intrahepatic ducts, where they mature into adults in about 1 mo. Symptoms of Clonorchiasis include heavier infections can cause fever, chills, epigastric pain, tender hepatomegaly, mild jaundice, and eosinophilia. Chronic cholangitis in heavy infections may progress to atrophy of liver parenchyma, portal fibrosis, and cirrhosis. Jaundice may occur if a mass of flukes obstructs the biliary tree. Other complications include suppurative cholangitis, cholelithiasis, pancreatitis, and, late in the course, cholangiocarcinoma. Diagnosis of Clonorchiasis includes finding eggs in the feces or duodenal contents.
In Ireland one outbreak was reported in 1998 accounting for 2.4% of all food-related outbreaks; 2(45) cases in 1999;1 (9) cases in 2000; 1 (11) cases in 2009.
For treatment of Clonorchiasis there is only one medicine Praziquantel. It should be administered at the dose of 25 mg/kg 3 times daily for 2–3 consecutive days or of 40 mg/kg, single administration.
Clonorchiasis ongoing research
Some of the ongoing research studies on Clonorchiasis are ClonorESTdb: a comprehensive database for Clonorchis sinensis EST sequences, Cholangiocarcinoma: descriptive epidemiology and risk factors.