Blood Test For Opisthorchiasis - How To Prepare And Conduct

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Blood Test For Opisthorchiasis - How To Prepare And Conduct
Blood Test For Opisthorchiasis - How To Prepare And Conduct

Video: Blood Test For Opisthorchiasis - How To Prepare And Conduct

Video: Blood Test For Opisthorchiasis - How To Prepare And Conduct
Video: Blood Test Procedure | Nuffield Health 2023, December

Opisthorchiasis is a helminth disease that is caused by parasitic flatworms of the fluke class. The disease is difficult - fever, abdominal pain, jaundice, dyspepsia may occur. Analysis for opisthorchiasis is carried out in many laboratories and helps to diagnose the presence of parasites in a timely manner.

The content of the article:

  • 1 Opisthorchiasis
  • 2 Diagnosis of the disease
  • 3 Research methods
  • 4 What should serve as a signal for taking tests
  • 5 How to properly prepare for the study
  • 6 General information about the study
  • 7 What the research is used for
  • 8 When a study is scheduled
  • 9 What the results mean
  • 10 Important notes


Blood test for opisthorchiasis
Blood test for opisthorchiasis

Opisthorchiasis is a serious disease from the group of helminthiasis that affects the liver and pancreas. The causative agent of opisthorchiasis - Siberian fluke, or feline (Opisthorchis felineus), parasitizes in humans, cats, dogs in the liver, gallbladder, biliary tract, pancreas. The main source of invasion is a sick person and animals, with the feces of which the eggs of the causative agents of opisthorchiasis fall into the water, where they are swallowed by snails, in which the parasite larvae multiply, ending in the release of cercaria larvae into the water.

Cercariae penetrate into carp fish (carp, crucian carp, asp, ide, dace, roach, bream, tench, chebak). Infection of the final hosts (humans and mammals) with opisthorchiasis occurs when raw, slightly salted, dried or insufficiently thermally processed fish containing invasive larvae are eaten.

Distinguish between acute opisthorchiasis (from several days to 4-8 weeks or more) and chronic opisthorchiasis (lasts 15-25 years and even for life).

Acute opisthorchiasis is characterized by:

  • fever
  • hives
  • aching muscles and joints,
  • later pains appear in the right hypochondrium, in the epigastric region,
  • there is an increase in the liver and gallbladder,
  • pain and a feeling of heaviness in the epigastrium appear,
  • nausea,
  • vomiting
  • heartburn,
  • frequent loose stools
  • flatulence,
  • decreased appetite.

Fibrogastroscopy reveals:

  • erosive gastroduodenitis,
  • stomach ulcers
  • duodenal ulcers.

Chronic opisthorchiasis is manifested by symptoms:

  • chronic cholecystitis,
  • gastroduodenitis,
  • pancreatitis,
  • hepatitis A.

There are persistent paroxysmal pains in the right hypochondrium, resembling biliary colic, passing into the right half of the chest. There is a dyspeptic syndrome, pain on palpation at the point of the gallbladder, dyskinesia of the gallbladder.

The stomach and intestines are also involved in the pathological process, which is manifested by signs of gastroduodenitis and intestinal dysfunction, pancreatitis (the usual consequences of opisthorchiasis).

Opisthorchiasis invasion leads to disruption of the nervous system, as evidenced by the frequent complaints of patients about:

  • increased fatigue,
  • irritability,
  • insomnia,
  • headache,
  • dizziness.

Sweating, tremors of the eyelids, tongue, fingers are observed. In some cases, neurological symptomatology in the case of opisthorchiasis comes to the fore, and the patient is diagnosed with neurocirculatory dystonia and autonomic neurosis. Asthenic syndrome manifests itself in complaints of rapid physical fatigue, general weakness.

Allergic syndrome in chronic opisthorchiasis is manifested:

  • itchy skin
  • hives
  • Quincke's edema,
  • arthralgia,
  • food allergies.

Diagnosis of the disease

Diagnosis of opisthorchiasis at an early stage of the disease is very difficult. The eggs of parasites can be found in the feces of a patient at least 4 weeks after infection. Therefore, the diagnosis is often made through a survey. The doctor, as a rule, asks the patient about where he has been recently, whether he ate raw, dried, fried fish.

If a deterioration in the patient's well-being began a few days after eating fish, the specialist diagnoses opisthorchiasis.

Diagnosis of the disease includes instrumental and laboratory research:

  • General urine analysis;
  • Clinical and biochemical (blood a-amylase, AST, ALT, cholesterol level, plasma protein composition, alkaline phosphatase) blood tests;
  • Coprology (feces analysis);
  • Ultrasound of the abdominal organs;
  • Fibrogastroduodenoscopy (endoscopic examination of the stomach, esophagus and duodenum);
  • Study of blood serum for the presence of antibodies to opisthorchis.

Opisthorchiasis requires mandatory qualified treatment. This disease can cause complications such as pancreatitis, inflammation of the biliary tract, biliary peritonitis, and in some cases, cirrhosis or liver cancer.

Research methods

Enzyme-linked immunosorbent assay (ELISA).

What should serve as a signal for taking tests

Blood test for opisthorchiasis
Blood test for opisthorchiasis

The following symptoms should be a signal for testing: allergic manifestations, pain in the epigastric region and in the right hypochondrium, nausea, profuse salivation, vomiting, dizziness, weakness, headaches, enlarged liver, erosive-ulcerative gastritis, allergic hepatitis, etc.

How to properly prepare for the study

Do not smoke for 30 minutes before donating blood.

General information about the study

Blood test for opisthorchiasis
Blood test for opisthorchiasis

The study is being carried out to detect infection with a trematode of the Opistorchidae family, Opistorchis felineus (feline fluke, or Siberian fluke) - flatworms that cause the development of opisthorchiasis.

The main source of infection is domestic and wild animals that feed on fish, as well as humans infected with O. felineus. In their bodies, the final maturation of the parasites to adults occurs, which produce eggs that are excreted into the environment with feces. When they enter water bodies, the eggs are swallowed by mollusks by bitinia (the first intermediate host), in which the development and asexual reproduction of the helminth takes place with the formation of larvae - cercariae. Cercariae are freed from molluscs and actively penetrate into carp fish (the second intermediate host), encysting in muscles and subcutaneous fat in the form of metacercariae. A person becomes infected by eating insufficiently processed fish containing O. felineus metacercariae.

After they get inside, the formation of adults of the parasite begins in the duodenum. Then they migrate to the bile and pancreatic ducts, where they reach sexual maturity after a few weeks, and after a month they begin to lay eggs.

Adults of O. felineus attach to the mucous membrane of the bile and pancreatic ducts, causing mechanical damage to their walls. The accumulation of a large number of parasites in the ducts can cause their blockage and, as a result, secondary jaundice and pancreatitis, and also creates favorable conditions for the addition of a secondary infection of the biliary tract. The waste products of opisthorchis are strong allergens and lead to allergic reactions and eosinophilia.

Opisthorchiasis can occur in various forms, often asymptomatic. The main signs of infection with O. felineus: fever, general malaise, skin rash, gastrointestinal disturbances, with massive invasions - pain in the right hypochondrium, possibly enlarged liver and spleen.

With a long course, the disease becomes chronic, chronic cholecystitis, duodenitis and pancreatitis develop.

If the patient is not treated in the early stages, he may develop serious complications, such as purulent cholangitis, rupture of cystic-dilated bile ducts followed by biliary peritonitis, acute pancreatitis. It has been proven that chronic O. felineus lasting more than 20 years can lead to primary liver cancer.

What the research is used for

Blood test for opisthorchiasis
Blood test for opisthorchiasis

The test is carried out in order to identify the trematode of the Opistorchidae family - Opistorchis felineus (cat fluke, or Siberian fluke), which causes the development of opisthorchiasis. The survey is especially recommended for people who are at risk - living or who have ever been in an endemic area, for example, fishermen, indigenous peoples of the North.

There are several methods that can be used to test for opisthorchiasis. One of them is the determination of antibodies to the pathogen in the blood.

When a person comes into contact with Opistorchis felineus, their immune system reacts by producing IgM and IgG antibodies.

Immunoglobulins of class G to O. felineus in detectable quantities appear in the blood after 6-8 weeks from the moment of infection. Their concentration increases and after 2-3 months reaches a maximum, remaining at a certain level for a long time.

However, with long periods of the disease (more than 10 years), the level of specific antibodies significantly decreases and falls below the threshold value due to the development of the patient's immunodeficiency state and the adsorption of plasma proteins on the cuticle of the parasite.

It is advisable to use this test as an addition to complex examination methods.

When the study is scheduled

Determination of IgG antibodies to opisthorchiasis is usually not a routine test and can be prescribed by a doctor in the following cases:

  • when the patient has signs of liver, gallbladder, or pancreatic involvement, indicating a possible infection by trematodes,
  • for epidemiological indications - when living in endemic areas,
  • when eating poorly processed carp fish,
  • the patient is in a high-risk group (fishermen, indigenous peoples of the North).

What the results mean

False positive test results are possible for the following diseases:

  • Blood test for opisthorchiasis
    Blood test for opisthorchiasis

    A positive result means the patient is infected with Opistorchis felineus. However, a negative result does not always mean that the patient does not have opisthorchiasis Toxoplasmosis - 5.6%;

  • Toxocariasis - 7.3%;
  • Echinococcosis - 15.4%;
  • Trichinosis - 20.0%
  • Fascioliasis - 29.4%

The indigenous inhabitants of the zone of natural foci of opisthorchiasis (Ob-Irtysh basin) have low levels of antibodies due to innate tolerance to the pathogen.

  • Reference values
  • Result: negative.
  • KP (coefficient of positivity): 0 - 0.84.

Reasons for a negative result:

  • No infection.
  • Too early infection, when the immune response has not yet developed.
  • Long term disease (more than 10 years).

Reasons for a positive result:

  • Acute opisthorchiasis.
  • Latent opisthorchiasis.
  • Primary liver cancer associated with opisthorchiasis.

A positive result means the patient is infected with Opistorchis felineus. However, a negative result does not always mean that the patient does not have opisthorchiasis.

A positive result in a previously seronegative patient confirms the primary infection.

A negative result for IgG antibodies to Opistorchis felineus may indicate the absence of infection or its too early period when an immune response has not been developed.

In addition, a negative result can be observed with a long duration of the disease, due to the patient's immunodeficiency state and the adsorption of plasma proteins on the cuticle of the parasite.

Important notes

  • The examination for opisthorchiasis must necessarily be comprehensive, include anamnesis, clinical picture and laboratory data, including the detection of the pathogen and the results of a serological examination. Moreover, confirmation of the diagnosis by laboratory data is required.
  • It is necessary to take into account the epidemiological history: being ever in an endemic area, eating poorly thermally processed carp fish.
  • The disease is not spread from person to person.
  • If opisthorchiasis is detected, a full course of treatment must be carried out, otherwise serious complications may develop, up to liver cancer.
  • The basis for the prevention of opisthorchiasis is the exclusion of non-disinfected fish from food.

Find out more:

  • Opisthorchiasis - symptoms, causes, diagnosis and treatment
  • Opisthorchiasis - home treatment with folk remedies