Blood Test For Echinococcus - Decoding, Norm And Preparation

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Blood Test For Echinococcus - Decoding, Norm And Preparation
Blood Test For Echinococcus - Decoding, Norm And Preparation

Video: Blood Test For Echinococcus - Decoding, Norm And Preparation

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Video: Parasitology 143 a Casoni Test Skin Hydatid disease Intradermal injection Echinococcus granulosus 2023, February
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When and to whom the analysis for echinococcus is shown

Content

  • 1 Echinococcus, its life cycle and routes of infection
  • 2 The clinical picture of echinococcosis
  • 3 Diagnostics
  • 4 Preparing for blood donation for ELISA
  • 5 How long to wait for an answer?
  • 6 Analysis results
  • 7 Treatment
  • 8 Prevention of infection

An analysis for echinococcus should periodically be taken by persons whose professional activities involve contact with animals - veterinarians, livestock breeders, dog handlers, since they are at an increased risk of infection by the larvae of this dangerous helminth. Also, a blood test for echinococcus can be prescribed in conjunction with other diagnostic measures if this disease is suspected.

Echinococcus, its life cycle and ways of infection

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Echinococcus, its life cycle and ways of infection

Adults of echinococcus are tapeworms 3-5 mm long. These sexually mature parasites live in the small intestines of dogs, wolves, foxes, bears, and occasionally cats, where they reproduce. Echinococcus eggs, together with excrement, go out into the environment, where they are carried by animals and the wind, polluting grasslands and water.

Cattle grazing on pastures seeded with Echinococcus eggs and drinking contaminated water becomes infected and becomes the carrier of the larval stage of helminth - its intermediate host. This stage of development of the parasite is characterized by the formation and growth of rounded cysts (Finn) filled with fluid in the internal organs. The larval stage of development of echinococcus can last for years until its larvae enter the intestinal tract of the main host - dogs, wolves, while they eat the organs of a dead sick animal.

Once in the human intestinal tract, the eggs of the echinococcus are transformed into larvae and penetrate through the walls of the small intestine into the veins, from where they are carried by the bloodstream throughout the body. Getting into various organs, the larvae form cysts in them (Finns), which can exist for more than a dozen years, gradually growing to the size of a baby's head.

The clinical picture of echinococcosis

The clinical manifestations of echinococcosis depend on how many parasite larvae have entered the bloodstream, and into which organs they have managed to penetrate. In its development, the disease goes through several stages:

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  • I - from the moment of infection until the first signs of the disease appear (this period can last from six months to 5 years);
  • II - the appearance of mild disorders of well-being, subjective signs;
  • III - pronounced symptoms, depending on the localization of growing cysts;
  • IV - the appearance of complications.

Important! A blood test for echinococcosis makes it possible to identify a parasitic disease in the early stages, before the appearance of objective symptoms caused by pressure on the organs of the growing Finns.

Echinococcosis may not manifest itself for many years, sometimes the detection of echinococcal cysts occurs during prophylactic ultrasound of the internal organs, before objective symptoms appear. The development of the clinical picture is due to the localization of the parasite.

In most cases, the liver is affected by the larvae of echinococcus. The symptoms are similar to the manifestations of other diseases of this organ - pain and heaviness on the right under the ribs. A complication is suppuration and rupture of an echinococcal cyst, which are fatal.

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The second, according to the frequency of cases, the dwelling of helminth larvae in the body is the lungs. The growing cyst, squeezing the tissue, causes chest pain, shortness of breath, and cough. With large Finn sizes, rib deformities appear. Complications include pneumonia, pleurisy, suppuration and rupture of the cyst.

More rare cases of echinococcus lesions of the kidneys, brain, heart, bones, biliary tract, peritoneum, spleen, spinal cord. In terms of symptoms, echinococcosis is similar to tumor processes of the same localization, therefore it is important to differentiate these diseases. It helps to do a blood test for echinococcosis.

Diagnostics

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For the diagnosis of echinococcosis, such modern diagnostic methods as ultrasound, CT, MRI are used, which allow us to detect the localization and size of echinococcal cysts. However, these methods are useless in the early stages of the disease, when the Finns have not yet formed, or are not large enough to detect them.

A blood test for echinococcus helps to diagnose echinococcosis in the initial stages. This laboratory test is called enzyme-linked immunosorbent assay (ELISA), it is based on the detection of antibodies to various infections in the blood serum. ELISA is used not only for blood tests for echinococcosis, it is used to detect a variety of bacterial and viral infections, HIV, STDs, autoimmune, hormonal and oncological diseases.

Before the advent of the blood test for echinococcosis by the ELISA method, they practiced the skin-allergic test, proposed by the Italian doctor Cazoni at the beginning of the twentieth century. It consists in the intradermal administration of antigens isolated from helminth larvae. According to the local reaction (absence or appearance of redness at the injection site), a conclusion was made about the absence or presence of infection of the body with echinococcus.

However, Kazoni's test does not always give a reliable result; errors occur in almost 50% of cases. In addition, during its implementation, there is a significant risk of anaphylactic shock. In this regard, the diagnosis by the Cazoni test is rarely used today.

The ELISA method is based on the body's immunological response to the ingress of foreign microorganisms. As you know, when pathogenic bacteria, viruses or other foreign bodies enter the body, the immune system produces special proteins - antibodies (immunoglobulins) to fight them. By the presence and type of antibodies contained in the patient's blood serum, it is possible to determine the presence of infection, its type, as well as the stage of the disease.

At different stages of echinococcosis, antibodies of different classes are produced. There are 3 classes of immunoglobulins in total, which are designated:

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  • IgM;
  • IgA;
  • IgG.

When an infection enters the body, IgM antibodies are produced first and are detected within 1 to 3 weeks from the onset of the disease, or from the moment of exacerbation of chronic processes. These immunoglobulins actively perform their functions for about 3 months (sometimes up to 2 years), and then disappear and are not detected in blood serum.

Immunoglobulins of the IgA class are characteristic of the chronic course of processes, they are detected after 4 weeks (appear earlier) and disappear only after the complete destruction of the infection in the body.

IgG antibodies start to be produced from 4 weeks after infection. Their presence in the blood indicates the presence of immunity to the previous disease or the carrier of the infection. They can remain in the blood for more than one year, and for certain diseases - for life.

In addition to ELISA, a general detailed blood test can serve as an indirect method for diagnosing echinococcosis. An increased level of eosinophils may serve as an indication of the presence of a parasitic invasion.

Preparing for blood donation for ELISA

The material for ELISA is taken from a vein in the elbow area in an amount of up to 5 ml. Before taking blood, the following rules must be observed:

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  • Blood sampling for echinococcosis is performed on an empty stomach;
  • At least 14 days before the day of the study, it is necessary to stop taking medications (if the patient is undergoing treatment with antibiotics, antiviral or antiparasitic drugs, then it should be suspended);
  • For several hours before taking an analysis for echinococcosis, smoking is prohibited.

How long to wait for an answer?

The enzyme-linked immunosorbent assay does not require lengthy research. It can be produced within 24 hours after the delivery of the material. Delays in the blood test for echinococcus can only be associated with the problematic timeliness of studies due to the overload of the laboratory.

Analysis results

Depending on the presence or absence of antibodies of each class, as well as their combination and quantity, which was shown by a blood test for echinococcus, decoding is performed by a specialist. The answer is usually formulated as:

  • Negative when no parasites are found;
  • Positive when there is an infection with echinococcus larvae.
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Analysis result

When analyzed for echinococcus, the concept of a norm does not exist, since the presence of this parasite in the body cannot be the norm, even if it is only one larva that has invaded some organ.

Attention! There is a possibility that infection with echinococcus has occurred, but at the time of blood sampling for IFO, antibodies in sufficient quantity for their detection had not yet been developed. To exclude the unreliability of the analysis for echinococcus, it must be repeated with an interval of 4 weeks.

Treatment

In the early stages of echinococcosis, until the Finns have formed, treatment with antiparasitic drugs is possible. But in most cases it is necessary to resort to surgical methods of removing echinococcal cysts.

With a small size, the Finn can use a modern minimally invasive surgical method through punctures under the control of ultrasonic waves under local anesthesia. In this case, trauma to the affected organs will be minimal.

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Echinococcal cyst removal

With a medium size and a small number of echinococcal cysts, laparoscopic operations with general anesthesia can be used. Depending on the stage of the process, only Finns can be removed, or Finns with an adjacent part of the organ.

With large sizes of a Finn, as well as in cases of suppuration and rupture of echinococcal cysts, open surgical interventions are performed using the method of laparotomy under general anesthesia. In this case, resection can be carried out, and, if necessary, ectomy (complete removal of an organ), for example, a kidney or gallbladder.

In the postoperative period, therapeutic treatment is prescribed and a second diagnosis is performed, including a blood test for echinococcus, the decoding of which can confirm or question the effectiveness of the treatment performed.

In the future, the patient stays on the dispensary for at least 10 years, with mandatory systematic examinations at least once every two years.

Prevention of infection

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Prevention of infection

Echinococcus is one of the most dangerous helminths, the consequences of infection with its larvae can be tragic. To avoid the danger of infection with echinococcus, the following rules must be strictly observed:

  • Systematically conduct deworming of domestic dogs and cats with anthelmintic drugs;
  • Make sure that pets do not find food outside the house, especially when traveling out of town;
  • Thoroughly wash hands with soap, using a nail brush, after touching animals, before eating, after natural needs;
  • Do not drink unboiled water from open sources;
  • Wash vegetables, fruits and berries before eating;
  • Medicinal herbs collected in nature should be thoroughly washed and heat treated (decoctions, infusions of boiling water), or insist on alcohol;
  • Ensure sufficient heat treatment of meat, especially for livestock by-products - liver, lungs, kidneys;
  • Persons whose professional activity is associated with contacts with animals and wildlife (veterinarians, livestock specialists, furriers, livestock breeders, dog handlers, butchers, gamekeepers, hunters, etc.) need to periodically take a blood test for echinococcus in order to timely identify the invasion, if it is happened.

Attention! If you suspect yourself of the possibility of infection with echinococcus, you can not self-medicate! Traditional methods are powerless against echinococcosis! It is necessary to contact a specialized medical institution, donate blood for echinococcosis, undergo other diagnostic procedures and, in case of a parasite, receive qualified medical care.

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