Fever, chills, nausea, vomiting, pain and tenderness in your right upper abdominal area can all be symptoms of a problem with your gallbladder. Eating raw fish that has become infected with a worm called Clonorchis sinensis can cause these symptoms, because the worm will migrate from your intestines to your bile ducts and gallbladder.
Clonorchis Sinensis
Clonorchis sinensis is a trematode, or a type of worm that is also referred to as a fluke. It can infect the bile ducts that carry bile from the liver and gallbladder to the small intestines; it can also infect the gallbladder. In fact, C. sinensis can live as long as 50 years in the bile ducts and gallbladder of an infected human, releasing as many as 2,000 eggs a day, according to Kenneth Ryan, M.D., Emeritus Professor of Pathology and Microbiology at the University of Arizona College of Medicine in "Sherris Medical Microbiology."
Life Cycle
As shown in the diagram on the website of the Centers for Disease Control and Prevention, the eggs will travel down the bile ducts to the small intestines, then large intestines, to exit in the bowel movements. The eggs may then be eaten by snails, where they change into another form, only to leave the snails and enter into a freshwater fish, where they will change their form again. If you eat raw fish that has been infected with C. sinensis, the worm will travel to your small intestines, then migrate up to the bile ducts and mature to an adult worm in approximately 30 days.
Symptoms
As the larva form travels from the small intestines to the bile ducts and gallbladder, your body experiences fever and chills. Clonorchis can destroy the lining of the bile ducts; this can gradually cause the walls of the bile ducts to become thick and sometimes, the walls can rupture and release worms into the surrounding area, as described in the "Foundations of Parasitology" by Larry Roberts of the University of Miami. While a mild infection may not cause any symptoms, an infection of at least 500 worms can cause bile stones. Dead Clonorchis can block the flow of bile within the bile duct, causing jaundice and a bacterial infection.
Diagnosis
Blood tests may show that your eosinophils, bilirubin and alkaline phosphatase are higher than normal, but this cannot pinpoint what is wrong, per Richard Pearson, M.D., Professor of Medicine and Pathology at the University of Virginia School of Medicine in "The Merck Manual for Healthcare Professionals." The eosinophils are white blood cells that increase when you have any parasitic infection. Bilirubin increases when the bile flow is blocked, while an increase in alkaline phosphatase can mean a problem in the bile ducts or liver. The diagnosis is made when the lab finds Clonorchis eggs in your stool sample.
References
- Centers for Disease Control and Prevention: Life Cycle
- "Foundations of Parasitology"; Larry Roberts, John Janovy, Jr.; 1996
- "Review of Medical Microbiology and Immunology"; Warren Levinson, M.D., Ph.D.; 2008
- "Sherris Medical Microbiology"; Kenneth Ryan, M.D., C. George Ray, M.D.; 2010
- "The Merck Manual for Healthcare Professionals"; Clonorchiasis
