Chinese liver fluke

Chinese liver fluke: description

The Chinese liver fluke (Clonorchis sinensis or Opisthorchis sinensis) is a small, lanceolate-like worm. The parasite causes in humans the infectious disease clonorchiasis (opisthorchiasis). Sometimes related species cause the disease: Opisthorchis felineus (cat’s liver) and Opisthorchis viverrini.

Chinese liver fluke belongs to the class of sucking worms (trematodes) and is a hybrid. It is mainly distributed in Southeast Asia, but also in Eastern Europe. The parasite needs a host to feed on. Depending on the stage of development, it parasitizes in various host animals, including humans. In East Asia, about 40 million people are affected by the Chinese liver fluke.

Chinese liver fluke: symptoms

A Chinese liver fluke mainly affects the bile ducts. Therefore, the clonorchiasis manifests itself mainly by complaints that are caused by a transfer or inflammation of the biliary tract. These include:

• anorexia
• bloating
• diarrhea
• Gallbladder inflammation (cholecystitis) with pain in the right upper abdomen
• Liver inflammation (hepatitis)
• Jaundice (jaundice): discoloration of the conjunctiva of the eyes and skin

Chinese liver fluke infestation does not always cause complaints. Many patients do not notice him. Only when there are over 100 worms in the body do patients complain of symptoms.

Chinese liver fluke: causes and risk factors

As a parasite, a Chinese liver fluke uses other creatures to multiply and mature. When the larvae (Mirazidien) of the Clonorchis sinensis get into fresh water, they look for there water snails as intermediate hosts. In them, they ripen to another larvae – the circus. These are released into the water where they can pierce the skin of carp-like freshwater fish, which they use as another intermediate host. If the freshwater fish is subsequently eaten by humans, dogs or cats, the larvae enter the bile ducts of these end hosts via the gastrointestinal tract. There they grow within about four weeks to sexually mature, two-centimeter liver flukes. They lay eggs that are excreted through the gut of the host.

Chinese liver fluke: risk factors

The main risk factor for infection with Clonorchis sinensis is the consumption of raw fish. Make sure that the fish is heated for a sufficiently long and strong (at 55 ° C) during preparation. As a result, the larvae die, and humans can no longer become infected.

A Chinese liver fluke also benefits from poor hygienic conditions. If faeces are not disposed of professionally, but the wastewater is discharged into surrounding waters, the worm eggs from the chair get into the fresh water. There they meet water snails, where they develop further.

Chinese liver fluke: examinations and diagnosis

If you feel ill after a stay abroad, you should first visit your family doctor. He interrogates you in detail about your medical history (anamnesis). Possible questions are:

• Where abroad were you?
• At what time were they there?
• Did you eat fish there?
• Since when are you having those complaints?

Subsequently, your doctor will examine you. He scans your stomach to check for pain. He then palpates the edge of the liver and spleen to detect possible enlargement of the organs. Frequently, physical examination for diarrheal diseases is not clear, so a stool sample from you in a lab needs to be analyzed for different pathogens. A Chinese liver fluke is not directly detected. Much more are sought in stool, bile or secretions from the duodenum (worm) worm eggs.

Chinese liver fluke: treatment

If worm eggs from the Chinese liver fluke have been detected in the stool, you will receive a drug containing the active ingredient praziquantel. This is a worm (antihelminthic) that can be swallowed. It paralyzes the Chinese liver fluke and kills it. The parasite is then excreted with the stool. Praziquantel must be taken for three weeks. Then the chair is examined again for worm eggs.

Chinese liver fluke: disease course and prognosis

With proper and rapid treatment, a Chinese liver fluke infestation has a good prognosis. Without therapy, the parasite can survive up to 30 years in the bile ducts of humans and lay eggs. The long and constant irritation of the bile ducts increases the risk of malignant diseases such as bile duct carcinoma. It also increases Chinese liver fluke– the risk of liver cirrhosis, gallstones, pancreatitis and enlargement of the liver and spleen (hepatosplenomegaly).