Blood Test For Parasites - An Informative Diagnostic Method

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Blood Test For Parasites - An Informative Diagnostic Method
Blood Test For Parasites - An Informative Diagnostic Method
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A blood test for parasites is the most reliable diagnostic method that helps to identify the presence of parasites in the human body. Tests for the detection of parasitic invasion can be microscopic, serological and hardware, each of which is shown to identify a specific type of parasite in the body. The most effective research methods is the donation of blood for parasites.

The content of the article:

  • 1 Parasites - what is it
  • 2 Ways of infection
  • 3 Danger of parasites
  • 4 Symptoms
  • 5 Complications of parasitic diseases
  • 6 Diagnostic methods
  • 7 Advantages and Disadvantages of Research
  • 8 What tests are needed to detect parasites
  • 9 Studies to identify parasites
  • 10 Blood test for parasites - studies in children
  • 11 Interpretation of ELISA results

Parasites - what is it

Parasites are understood to be microorganisms that live and feed on other organisms. At the same time, parasites not only live in the body of their host, but also harm it. Parasites are conventionally subdivided into phytoparasites and zooparasites. Phytoparasites include:

  • mushrooms;
  • bacteria;
  • some varieties of plants, etc.

Zooparasites include:

  • the simplest microorganisms;
  • helminths;
  • arachnids;
  • insects, etc.

Parasites also include various viruses that live in a foreign body at its expense.

Having settled in the body, parasites cause its weakening and exhaustion, which sometimes leads to death. Many parasites are capable of acting as the causative agent of diseases dangerous to human health.

Infection routes

There are several typical infection mechanisms:

  • What is the name of a blood test for parasites
    What is the name of a blood test for parasites

    Helminth eggs are in the ground, mixed with dust particles. Therefore, unwashed vegetables and fruits are dangerous from the point of view of infection. Helminth eggs are in the ground, mixed with dust particles. Therefore, unwashed vegetables and fruits are dangerous from the point of view of infection.

  • Water. Also, helminth eggs are found in water: not only standing (ponds), but also flowing (rivers), tap water.
  • Animals. Domestic animals (cats, dogs, ferrets). These animals can be intermediate hosts for various types of parasites.
  • Person. Parasitosis can be infected by the fecal-oral route. One of such methods can be inhalation of helminth cysts or eggs, which "fly" into the air, for example, in spring, when animal excrement is released from under the snow and with warm weather and wind is easily transported through the air.

Danger of parasites

If the number and size of parasites is small, their presence may go unnoticed for a long time, however, the rapid reproduction or growth of parasites, their movement through the body during the life cycle, is often the cause of the development of serious health problems.

For example, roundworms that accumulate in the intestines can cause constipation and obstruction. Bovine tapeworm grows up to several meters in length and seriously damages the digestive tract, deprives the host of nutrients and vitamins.

Echinococcus forms cysts in internal organs, including the brain, liver, and lungs. The rupture of such a cyst can occur unexpectedly, after a minor injury or during examination. The contents of the cyst can cause anaphylactic shock or collapse. Trichinella larvae feed and live in the muscles, gradually destroying them. According to the WHO, parasitic diseases account for about 14 million deaths in the world per year.


In most cases, the manifestations of parasite infestation are nonspecific. The presence of parasites in a person is difficult to establish, since infection with helminths can mimic other diseases, for example, attacks of cholecystitis or gastritis.

What is the name of a blood test for parasites
What is the name of a blood test for parasites

Parasitosis may be indicated by:

  • temperature increase,
  • weakness and lethargy
  • decreased performance and mood,
  • bad dream,
  • irritability,
  • stomach ache,
  • diarrhea or constipation
  • weight loss,
  • nausea and vomiting,
  • desire to eat unusual foods or inedible substances,
  • the appearance of a yellowish tint of the skin and sclera,
  • weight loss,
  • a tendency to various allergic reactions (most often of the type of urticaria).

The excretion of worms in the feces is an important symptom that indicates the causes of the ailment. However, this does not always happen, and the presence of parasites in the human body can be suspected only by indirect signs.

Worm infestations are often associated with malabsorption of nutrients and micronutrients. Worms in the human body cause a lack of important vitamins and minerals:

  • dry skin
  • hair loss,
  • brittle nails
  • violation of reproductive health (impotence, menstrual irregularities, infertility),
  • decreased memory
  • decreased visual acuity, etc.

Complications of parasitic diseases

Blood test for parasites. During the life or death of the parasite, toxic substances are released into the host organism. They can cause weakness, constant fatigue, dizziness, headache, nausea, decreased appetite. In addition, these substances provoke sensitization of the body, which causes allergies - rashes, dermatitis, bronchitis.

Many parasites choose the human gastrointestinal tract for habitation. When strengthened in the intestines, as well as nutrition, the parasites damage and destroy mucosal cells and blood cells. Extensive damage to the mucous membrane can manifest itself as pain, nausea, and digestive and nutrient problems.

A large number of parasites (for example, ascaris), entwining into a ball, can cause intestinal blockage and acute intestinal obstruction. The risk of this complication is especially high in young children, because they already have an intestinal lumen.

The parasite is so called because the interests of the host organism are not too concerned with. It takes all the necessary elements from food, depriving the host of many necessary nutrients - minerals and vitamins. Therefore, one of the consequences of parasitic diseases is hypovitaminosis and avitaminosis, which can manifest itself as a decrease in immunity, deterioration of the condition of the skin, nails, hair, etc. A significant loss of blood cells (due to the parasite feeding on them) and their insufficient formation (due to hypovitaminosis) leads to anemia.

What is the name of a blood test for parasites
What is the name of a blood test for parasites

A parasite like Trichinella lives in and feeds on muscles, causing severe muscle pain. Parasites that live or multiply in the bile ducts (for example, opisthorchias) can provoke a blockage of the bile ducts, which is manifested by jaundice of the skin and sclera, itching.

Parasites are a source of regular chronic damage to cells, which provokes their malignant changes and the development of cancer.

Another danger of parasites is that an infected person becomes, in most cases, the cause of infection of other people. As a result, all family members can get sick if one of them has the parasite.

Some parasites have a very complex life cycle to improve their survival, during which they change several hosts and exist in each in the form of different life forms. For echinococcus, for example, a person is a dead end of the life cycle and, getting into his body, the parasite forms cysts and capsules in various organs (brain, liver, lungs). The appearance of cysts in the brain can lead to the development of epilepsy and other neurological disorders. In addition, cysts are a source of abscess formation in internal organs.

To protect yourself and your loved ones from parasites, it is necessary to timely identify and treat parasitic diseases. A comprehensive examination for helminthiasis helps in this.

Diagnostic methods

What is the name of a blood test for parasites
What is the name of a blood test for parasites

A blood test for parasites is called a blood parasite immunoassay (ELISA). Using it, you can identify antibodies (immunoglobulin) that are produced in response to an antigen (foreign body). By the presence of complexes "antibodies-antigens" it is concluded that there are certain pathogenic organisms. ELISA will determine parasitic invasions even in the case of their negligible number of parasites. Blood sampling is carried out in the laboratory from a vein at the elbow. The results will have to wait about a week.

The polymerase chain reaction shows what is the causative agent of the infection, by creating for each its own genetic detector, which detects an exact copy of all DNA and reproduces a large number of such samples. Suitable for infections caused by protozoa. Material for research - any biological excretion (urine sample, plasma). The serological method of determination is the study of antibody responses to antigens (immunofluorenscence, hemagglutination, latex agglutination). The material for research is blood serum. The disadvantage of this method is the inability to determine the stage of the disease.

Hemoscanning is called a rather simple, but very informative research method by a drop of blood, by which it is possible to identify the larvae of worms. The drop is monitored through a microscope for some time.

These tests make it possible to verify if there is an infection. They also determine the type of helminths, the presence of viruses, the presence of fungi, the level of increase in leukocytes and erythrocytes. A complete blood count will also help diagnose harmful organisms if an eosinophil count is 20% higher than normal.

Research advantages and disadvantages

Blood test for parasites. The advantages of examining blood fluid for infectious parasite infections include:

  • full automation;
  • information content and reliability;
  • objectivity;
  • comfort of conducting;
  • early diagnosis of parasites;
  • the ability to analyze quality and quantity;
  • accuracy.


  • high price;
  • not available in every laboratory;
  • waiting time for the result - up to 7 days;
  • not always all reagents are available.

What tests are needed to detect parasites

What is the name of a blood test for parasites
What is the name of a blood test for parasites

Blood test for parasites. Detection of the presence of helminths in the body allows the study of blood and feces. Parasites that live in the intestines multiply with eggs or whole compartments with a large number of eggs, which are excreted along with stool. So a sick person becomes a parasite distributor. The analysis of feces is carried out in order to detect worm eggs and allows you to determine the presence of a helminth and its type (pinworms, tapeworm, etc.).

Since the active vital activity of the parasite is manifested by the release of toxic substances and sensitization of the body, characteristic changes in the blood formula can be seen in the analysis. A complete blood count helps detect an increase in the level of eosinophils and, less often, anemia. This study allows one to suspect or confirm the presence of a parasitic disease without specifying the type of parasite.

Blood test for parasites. Stool analysis is not always informative. The absence of worm eggs in the feces gives grounds to exclude only some types of helminthiasis. To detect other parasites, a blood test is carried out for antibodies to them (echinococcus, opisthorchia, trichinella, etc.). Determining the type of parasite helps the doctor to prescribe the necessary additional examinations or immediately choose the right treatment.

Tests for parasites can and should be taken if there is a suspicion of infection (the appearance of characteristic complaints and health problems), those who live in areas with an increased risk of infection, employees of child care facilities, the food industry, family members in which a parasitic disease was found, etc..d.

Timely detection and treatment of parasitosis avoids threatening complications and health problems.

Studies to identify parasites

The simplest test for the presence of parasites in the body is the analysis of feces. To carry out this analysis, a stool sample is placed in a special sterile container, which must be delivered to the research laboratory within 30 to 45 minutes. In the course of such work, laboratory specialists try to find eggs of worms and others in the provided sample. Such an analysis allows you to determine the existence:

  • round worms or nematodes;
  • flukes or trematodes;
  • tapeworms.

Unfortunately, such a study cannot offer high reliability of the result, which is associated with some features of the reproduction of helminths. Even if such an analysis is submitted more than once, its results still cannot be called reliable.

What is the name of a blood test for parasites
What is the name of a blood test for parasites

A more modern and effective method is a blood test for the existence of parasites. An enzyme-linked immunosorbent assay (ELISA) consists of detecting antigens and antibodies to parasites in a blood sample. If you pass such tests for parasites, then you can more likely determine the existence of a wide variety of microorganisms, and at the earliest stages of their appearance.

Blood test for parasites. In order to pass ELISA tests, it is enough to provide a blood sample taken from a vein. It will take no more than nine days to identify any parasite, and the results obtained will have a reliability of 95%.

Analyzes can be implemented in other ways as well. So, for this purpose, the following can be carried out:

  • X-ray and ultrasound examinations of organs;
  • endoscopy;
  • endobiopsy;
  • CT scan.

What kind of material needs to be submitted for research and how they will be implemented is usually decided by the doctor.

Blood test for parasites - studies in children

What is the name of a blood test for parasites
What is the name of a blood test for parasites

Parasitic infestation is especially common in children. The reason for this is inattentive adherence to the rules of personal hygiene. It has been statistically proven that every child at least once in his life suffers from helminthiasis. Giardiasis occurs more often in children 1-4 years old. If the child has a stool disorder, there are bouts of nausea in the morning, decreased or excessively increased appetite, weight loss, pallor of the skin, itching in the anus, teeth grinding in sleep, moodiness, pain in the navel - there is a risk that there is a parasitic pathology. This should be an incentive for parents to get tested for parasites.

Blood test for parasites. Standard research methods for suspicion of a parasitic process in a child's body are scraping for enterobiasis and analysis of feces for worm eggs. This is often enough to make a diagnosis. But if there are doubts, and the fecal analysis indicators did not give an unambiguous answer, it is better to check again. It is worth doing a detailed blood test for parasites (ELISA or PCR).

Interpretation of ELISA results

Blood test for parasites. Diagnostics is carried out in specialized medical institutions. ELISA results are expected for about a week, PCR results - for a couple of hours. Hemoscanning is performed in the presence of the patient. The interpretation of the results is carried out by a specialist in the field of parasitology. The meaning of the diagnosis is to detect antibodies, their three main types are determined: lgG, lgA, lgM. Depending on the positive or negative result, the following conclusions can be drawn for each of them:

  • in case of a negative result for the investigated infection, all three indicators will be with a sign (-): lgG (-), lgA (-), lgM (-);
  • if the disease is in the acute stage: lgG (+/-), lgA (+ -), lgM (+);
  • there is immunity: lgG (+), lgA (-), lgM (-);
  • chronic disease: lgG (+/-), lgA (+ /), lgM (-);
  • exacerbation of a chronic disease: lgG (+), lgA (+), lgM (+).

Antibodies lgM are fixed in the blood fluid no earlier than 2 weeks from the moment of infection, and lgG are stored in abundance during the course of the disease and for some time after recovery. "Pure", completely negative indicators will become only six months after the death of pathogenic organisms. An accurate decoding can be made by the attending doctor or a doctor who is familiar with the work of the laboratory in which the analyzes were carried out.

Find out more:

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  • Giardia in adults - symptoms, diagnosis and treatment
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