Clonorchis sinensis /klōnôr″kis sinen″sis/ , the Chinese or Oriental liver fluke, a trematode that is acquired by humans who eat raw, imperfectly cooked, pickled, salted, or smoked fish that is the intermediate host of the parasite. The fluke exists in a dormant stage as a cercaria, encysted in the skin of a fish and unable to continue its life cycle until ingested by a warm-blooded animal, in which the larvae mature and produce eggs. The eggs are excreted in the feces of the host to enter water, where the new generation evolves first in aquatic snails and then in fish. In human hosts the liver fluke lives in the bile ducts and gallbladder, causing chronic liver disease with enlargement of the liver, diarrhea, edema, and, eventually, death. Cholangitis, cholelithiasis, pancreatitis, and cholangiosarcoma are common complications and may be fatal. The adult fluke can survive in the biliary duct of its host for up to 50 years. Treatment is with praziquantel or albendazole. Also called Opisthorchis sinensis.
