Clonorchis sinesis infection causing mechanical obstruction of the bile ducts by the worms, through the mucosa of bile ducts.
Caused by infection related inflammation, including secondary bacterial infection, and toxic effects of worms.
Patients present with symptoms that are related to worm burden.
Patients with low infection intensity are often asymptomatic or have mild symptoms.
The lifecycle of C sinensis is characterized by an alternation of sexual and asexual reproduction in different hosts.
Eggs laid by hermaphroditic adult worms, which can survive in humans for up to 26 years, reach the intestine with bile fluids are eliminated with the feces.
After freshwater snails and ingest the eggs, miracidra hatch and penetrate into the intestinal wall.
Subsequently asexual reproduction, sporocyst, redial, and then cercariae are produced.
Cercariae escape from snails about 95 days after infection and adhere to freshwater fish.
After encysting in the subcutaneous tissues or muscles of the fish, cercariae develop into mature metacercariae within 45 days and when eaten raw or insufficient cooked infected fish by people, the metacerariae separated from the flash to gastric juice digestion.
Through the action of triypsin and endogenous proteases the metscerariae excyst in the duodenum.
Excysted juvenile flukes migrate via the ampulla of Vater to intrahepatic bile ducts where they develop into to adult flukes.
Eggs can be detected in feces around 4 weeks after infection.
The egg laying capacity of an adult C sinensis fluke varies and is estimated around 4000 eggs per worm per day.
Patient with high infection intensity often have nonspecific symptoms such as weakness, nausea, indigestion, headache, dizziness, vertigo, abdominal discomfort , diarrhea, or abdominal pain, particularly in the right upper quadrant.
Physical signs typically are jaundice, hepato- megaly, and liver tenderness.
Chronic infection with C. senensis results in liver and biliary complications which include: cholelithiasis, cholangitis, and cholecystitis.
Cholelithiasis is one of the most frequent complications of C. senensis.
May be associated with liver abscess and pancreatitis.
Developmental retardation has been reported in children who have heavy infection with a C. senensis.
Associated with cholangiocarcinoma.
Estimated yearly incidence of cholangiocarcinoma related to C. senensis infection is 25 per hundred thousand in females and 30 per 100,000 in males.
An infectious disease caused by the Chinese liver fluke, Clonorchis sinensis, and two related species.
Clonorchiasis is a known risk factor for the development of cholangiocarcinoma, a neoplasm of the biliary system.
Differential symptoms of parasite infection by raw fish: Clonorchis sinensis (a trematode/fluke), Anisakis (a nematode/roundworm) and Diphyllobothrium a (cestode/tapeworm) all have gastrointestinal, but otherwise distinct, symptoms.
Clonorchiasis sinensis is a trematode, fluke, which is part of the phylum Platyhelminthes.
It is a hermaphroditic fluke that requires two intermediate hosts.
The parasitic worm lives in the bile ducts of the liver, and is as long as 10 to 25mm.
The eggs of the worms are passed through fecal matter and then ingested by mollusks.
One becomes infected by eating undercooked, smoked, pickled salted freshwater fish.
Freshwater fish are a second intermediate host for the parasitic worm.
They become infected when the larvae of the worm penetrates the flesh of the fish.
Pathogenesis of infection can compasses mechanical obstruction of the bile ducts.
The water snail is the first intermediate host in which an embryonated egg discharged in stool goes through its developmental stages.
Endemic in the Far East, especially in Korea, Japan, Taiwan, and Southern China.
Clonorchiasis has been reported in non endemic areas following the ingestion of imported, undercooked or pickled freshwater fish containing metacercariae.