Liver fluke is a parasite that causes infection in the bile duct from consuming raw or undercooked fish or aquatic animals. Liver fluke lives in the body of humans or mammals to grow and lay eggs. As a result, the bile duct becomes chronically inflamed or blocked by eggs and parasites. Patients may therefore experience bloating, abdominal tightness, or fatigue. However, if the symptoms become severe, patients may have yellow eyes, yellow body , itching, or loss of appetite.
The most common liver fluke in Thailand is the species Opisthorchis Viverrini. It is elongated, flat, thin and transparent. When fully grown, it can be 2-3 centimeters wide and 5-10 centimeters long and can live in the bile duct of the human liver for up to 26 years.
Symptoms of liver fluke In the early stages of infection, if the number of liver flukes is still small and the liver tissue is still inflamed or changes only slightly, the patient may not show any symptoms. But if a large number of liver flukes accumulate for a long time, causing chronic infection and more liver damage, the patient may start to show symptoms similar to common gastrointestinal diseases, such as:
- Feeling hot in the stomach area
- Indigestion, stomachbloating, flatulence
- Chronic diarrhea or alternating diarrhea with constipation
- backache
- Abdominal pain in the upper right quadrant due to hepatitis
- Pain under the right rib cage or below the sternum
- Palpable liver or lump in the upper right abdomen
- tired
If the patient has been sick for a long time but has not received treatment, the liver may become more inflamed and damaged, including parasites and parasite eggs blocking the bile duct in the liver , causing the patient to have symptoms of enlarged liver and gallbladder , yellow eyes and body occasionally, malnutrition, and if the symptoms become more severe, the patient may have the following symptoms:
- The pain in the upper right abdomen is getting worse. The abdominal distension is from the enlarged liver.
- Loss of appetite, weight loss
- Have a low fever
- Itchy body
- Swollen limbs and often have fluid in the abdomen or ascites.
- Dark urine and pale stools
- Yellow body, yellow eyes
- Permanent bile duct obstruction
- The liver and gallbladder are so enlarged that they can be felt.
Causes of liver fluke
Liver fluke infection is usually caused by Opisthorchis viverini parasites that enter the liver bile ducts from consuming fish or aquatic animals that have infective larvae without being cooked to kill the parasites, especially freshwater fish such as carp, minnows, silver barb, whitefish, and white fish, or fish from processed and fermented fish such as fermented fish and food made from fermented fish such as som tam, jaew, etc.
The larvae of the liver fluke use the human bile duct to develop into adults, causing damage to the body and various illnesses. The life cycle of the liver fluke is as follows:
- Humans or other mammals ingest cystic or infective stages of the liver fluke .
- The larvae enter the small intestine and liver through the opening of the hepatic bile duct that opens into the small intestine and grows in the hepatic bile duct.
- The larvae live in the bile duct until they develop into adults and become worms.
- When humans or mammals that are hosts of liver fluke defecate in an inappropriate place, liver fluke eggs mixed in the feces will contaminate water sources and be eaten by freshwater snails, such as the bitter snails. The larvae then live in the body of the freshwater snails and develop into the cercaria stage.
- The cercaria larvae burrow out of freshwater snails into water sources and live in freshwater fish until they develop into metacercaria cysts or infective larvae.
- When humans or other mammals consume fish infected with the parasite, the parasite grows and lays eggs in the bile ducts of the liver.
Diagnosis of liver fluke
Initially, the doctor may diagnose the symptoms by asking the patient about the place of residence, food consumed, and any symptoms that appear. Then, a stool sample may be examined under a microscope to find parasite eggs. However, if no eggs are found, the doctor may have to diagnose by looking for antibodies (Antigen) to liver fluke in the stool or blood.
In addition, if liver enlargement is found, the doctor may order an ultrasound or CT scan to look for additional complications from liver fluke disease.
Treatment of liver fluke
For proper treatment of liver fluke, the doctor may need to consider the results of the worm egg diagnosis, the severity of the infection, and any complications that may occur. Treatment for liver fluke is as follows:
Drug use
- Praziquantel is administered in doses of 25 mg/kg body weight 3 times after dinner or before bedtime, or 40-50 mg/kg body weight once. After that, the parasite eggs in the feces will disappear within 1 week.
- Antibiotics are used for patients with concomitant bacterial infections.
Surgery
If complications arise in the biliary tract, surgery may be required.
In addition, some patients may need to receive supportive treatment for their symptoms, such as taking painkillers, inserting a tube into the bile duct to drain bile, reducing jaundice, or occasionally draining fluid from the stomach when there is severe abdominal distension due to fluid in the stomach, etc.
Complications of liver fluke infection
Patients with liver fluke infection may experience the following complications:
- Anemia
- Bacterial infection
- Infectious cholangitis
- Cholecystitis
- Pancreatitis
- liver cirrhosis
- Bile duct cancer
- Bloodstream infection and spread of infection throughout the body
Prevention of liver fluke
Since liver fluke infection is caused by ingesting liver fluke, changing your eating habits is the best prevention, as follows:
- Stop eating raw, semi-cooked, or processed fish or freshwater animals, such as fermented fish.
- Always cook fish or freshwater animals thoroughly before consuming at a temperature of at least 70 degrees Celsius.
- If you want to eat raw fish, you should freeze the fish at a temperature below -20 degrees Celsius for 7 days before eating.
After recovery, you should check your stool periodically as advised by your doctor to prevent recurrence.
