Antibodies To Lamblia: What Is It, Decoding Of Indicators

2023 Author: Riley Dean | [email protected]. Last modified: 2023-11-27 09:15

Antibodies to lamblia are specific proteins produced by cells of the immune system in a child or adult. The synthesis of immunoglobulins is activated after helminthic infection. Giardiasis is an infectious disease that is widespread in the modern world. Infection usually occurs through water, but food is often the source of the hazard.

The content of the article:

1 Giardiasis
2 What is lamblia
3 How does infection occur
4 Types of antibodies
5 Evidence of which are antibodies
6 How does giardiasis manifest in adults
7 Why is giardiasis dangerous for a child
8 What are the consequences of giardiasis
9 Antibodies to lamblia antigens total IgA, IgM, IgG
10 How is giardiasis diagnosed?
11 Blood for antibodies to lamblia
12 How to get tested
13 Decoding analysis. How accurate are the results

Giardiasis

Giardiasis is a widespread disease caused by a member of the Protozoe Lamblia intestinalis family (Giardia Lamblia).

The source of the infection is a person infected with lamblia. The transmission of infection is carried out by the fecal-oral route. The main transmission factor is water, but the transfer can also be carried out through food products, on which lamblia cysts remain viable from 6 hours to 2 days, contact transmission from person to person is also possible. Giardia can cause serious intestinal diseases in humans, both in the form of epidemics and in the form of sporadic cases. Children are more susceptible to invasion by lamblia, their disease proceeds with more pronounced clinical signs.

Giardia infection can spontaneously disappear after 6 weeks, or it can persist for years. Colonizing the mucous membrane of the small intestine, the trophozoites of lamblia penetrate into the epithelium and cause a systemic immune response.

The effectiveness of these methods is about 50% due to the characteristic discontinuity in cyst secretion associated with the characteristics of the reproduction of giardia trophozoites. The detection of antibodies to lamblia antigens substantially complements the methods aimed at detecting lamblia in feces, although this test is also not always sufficiently sensitive. It is advisable to carry out the test after 1-2 weeks from the onset of clinical symptoms, if fecal studies in an earlier period did not give a result.

According to clinical studies, antibodies to lamblia antigens are detected in 39 - 42% of patients with pathology of the gastrointestinal tract. In 89 - 92% of them, giardiasis is confirmed by a positive test of fecal samples or duodenal contents for the presence of lamblia cysts. There is a problem of cross-reactions of lamblia antigens with other parasitic and somatic antigens, which give false positive results, therefore, to increase the reliability and reliability of the diagnosis of giardiasis, a comprehensive examination is necessary.

What is lamblia

The causative agent of giardiasis in humans is the well-known protozoal organism Lamblia intestinalis, which lives in the small intestine and causes indigestion.

In humans and animals, lamblia exist in two forms. In the form of a vegetative form ( such lamblia are called trophozoids ), they are found mainly in the upper parts of the small intestine, and when they enter the large intestine, they turn into cysts (spore form), which are excreted into the external environment with feces. Giardia in the form of cysts can be in a "conserved" state for a long time and only when favorable conditions come to turn into trophozoids.

Once in the intestine, lamblia turn into trophozoids, attaching to the surface cells of the mucous membrane and sucking nutrients out of it. Their life cycle is from three to forty days.

Antibodies to lamblia. Despite the fact that this is a fairly short period, the disease can proceed for a very long time, since repeated self-infection occurs all the time. As a result of the long existence of lamblia in the body, a syndrome of chronic endogenous intoxication is formed. With a reduced immune defense, this can lead to damage to almost all organs and systems of the body.

How does infection occur

There are three main ways of transmission of giardiasis:

water;
contact and household;
food.

Most often, infection occurs when drinking poorly treated tap water or water from open bodies of water. With the contact-household route, entry into the body is carried out through household items contaminated with cysts: linen, toys, dishes. Infection is also possible when eating foodstuffs infected with cysts, especially without heat treatment (vegetables, berries, fruits).

Types of antibodies

Latin letters are assigned to specific protein compounds. There are 5 types of antibodies to lamblia: A, D, E, G, M. They have several distinctive features:

individual specific gravity;
characteristic shape;
the period of formation after infection;
the ability to participate in the infection process in its own way.

ATs to lamblia IgA, IgM, IgG play a role in the processes caused by parasitic infections. Class E protein compounds indicate the presence of allergic reactions. Class D antibodies help build immunity.

Antibodies Evidence

Antibodies to lamblia. Each class of immunoglobulins defines its own range of problems:

class A antibodies indicate that the infection has entered an active phase (they are detected when lamblia has lived in the body for at least 30 days);
lamblia of the IgM class is found 2 weeks after infection with helminths;
proteins of type G replace immunoglobulin M, they are found at every stage of the development of giardiasis (the concentration of substances significantly decreases with the use of drugs selected by a doctor);
if IgM, IgG are simultaneously detected in the blood, it means: either primary giardiasis is in the initial stage of development, or the chronic form of the disease has worsened.

How does giardiasis manifest in adults

The incubation period of the disease lasts 1-3 weeks. As a rule, giardiasis proceeds without any manifestations. With a large number of parasites inside the human body, the disease proceeds with severe clinical symptoms and has an acute or chronic course.

Antibodies to lamblia. In the acute form, the disease begins with the appearance of a liquid, watery stool without mucus and blood. Pain appears in the epigastric region. A large amount of gas is formed that inflates the intestines, belching is observed. Patients have a decrease in appetite, nausea, vomiting, a slight increase in body temperature.

In most patients, the manifestations of the disease disappear spontaneously within 1-4 weeks. Then the disease becomes chronic, which is periodically manifested by bloating, pain in the epigastric region, and liquefied stools.

All patients with giardiasis show signs of vitamin deficiency: pallor of the skin, blue under the eyes, seizures in the corners of the mouth, allergic rashes.

Why is giardiasis dangerous for a child

In children, giardiasis develops much more often and is more severe than in adults.

Modern epidemiological studies have shown that about 30% of preschool children are infected with lamblia. Moreover, in most cases, giardiasis in a child is manifested by symptoms that mimic other diseases and make it difficult to identify the true cause of the disease.

Once in the child's intestines, lamblia begins to actively multiply, using the nutrients the child needs to grow. As a result, there is a lack of vitamins in the body, which inhibits the normal development of the child.

Antibodies to lamblia. In the process of life, lamblia also emit a number of toxic substances. This leads to severe allergization of the child's body and suppresses his immunity. For this reason, one of the common manifestations of giardiasis in children is: atopic dermatitis, bronchial asthma, chronic dry cough and frequent colds.

What are the consequences of giardiasis

Giardiasis can aggravate the course of any other associated diseases of the gastrointestinal tract. It masks them and promotes allergic reactions.

Situations are quite common when the diagnosis of giardiasis hides such chronic diseases of the gastrointestinal tract as inflammation of the pancreas, dyskenesia (impaired motor activity) of the gallbladder, inflammation of the intestines of various kinds, etc.

The nervous system is often affected. Patients complain of general weakness, fatigue, irritability, shallow sleep, anxious dreams, headaches, and dizziness. Development of hypotonic crises with fainting conditions is possible. Vegetative-vascular dystonia and arrhythmia are quite common.

In chronic giardiasis in children and adults, skin lesions are detected: pallor, uneven skin color ("multi-colored skin"), lesions of the red border of the lips. The severity of the lesions is different: from slight peeling and dryness to pronounced cheilitis with cracks, seizures.

In connection with the discovery of lamblia in the feces in a child and the appearance of characteristic complaints in him, an additional examination is required in order to identify latent chronic inflammatory diseases of the gastrointestinal tract.

Antibodies to lamblia antigens total IgA, IgM, IgG

Antibodies to lamblia. Giardiasis is a widespread disease caused by a member of the Protozoe Lamblia intestinalis family (Giardia Lamblia).

The source of the infection is a person infected with lamblia. The transmission of infection is carried out by the fecal-oral route.

The main factor of transmission is water, but the transfer can also be carried out through food products, on which lamblia cysts remain viable from 6 hours to 2 days, contact transmission from person to person is also possible. Giardia can cause serious intestinal diseases in humans, both in the form of epidemics and in the form of sporadic cases. Children are more susceptible to invasion by lamblia, and their disease proceeds with more pronounced clinical signs.

Lamblia intestinalis invasion of the mucous membrane of the small intestine can give a different clinical picture: from asymptomatic to allergic symptoms and diarrheal syndrome, which is especially difficult with severe immunosuppression.

Although giardiasis has been known for a long time, there are serious problems in its diagnosis. Traditionally, it is carried out by detecting cysts or trophozoites of lamblia in fecal samples or duodenal contents. The effectiveness of these methods is about 50% due to the characteristic discontinuity in cyst secretion associated with the characteristics of the reproduction of giardia trophozoites. The detection of antibodies to lamblia antigens substantially complements the methods aimed at detecting lamblia in feces.

How is giardiasis diagnosed?

The variety of clinical manifestations of giardiasis and the absence of symptoms characteristic only of this disease require mandatory laboratory confirmation of the diagnosis. Feces and duodenal contents serve as research material. Only trophozoids are found in duodenal contents, only cysts are found in formalized feces, and trophozoids and cysts are found in liquid and semi-formed feces.

Currently, in order to diagnose giardiasis, a number of techniques are used that differ in sensitivity, specificity and general availability.

The most accessible method for laboratory diagnosis of giardiasis is scatological examination. When conducting research, it must be remembered that cysts in feces can not always be found. The inconsistent excretion of cysts with feces requires repeated examination of feces, as well as the use of other laboratory research methods.

Antibodies to lamblia. Patients with clinical manifestations of giardiasis, but with a negative result of the study of feces, it is advisable to examine a graduate student of the duodenum or upper jejunum. As a rule, it contains a large number of lamblia, including trophozoids (they are visible in fresh smears).

The analysis of failures in detecting lamblia in the study of feces made it possible to systematize the main reasons for false negative results. These include:

incorrectly collected material for research;
submission to the laboratory of feces against the background of taking medications that damage the morphology of parasites;
laboratory research errors;
examination of feces in the so-called "silent" period, when the secretion of lamblia cysts stops (8-14 days).

Identification of lamblia is possible already in 76% of patients with the elimination of these reasons during the first examination of feces. After the second study, the probability increases to 90%.

The most reliable method for diagnosing giardiasis is a duodenal biopsy. The indications for duodenal biopsy are:

a typical clinical picture of giardiasis;
negative result of scatological studies;
one of the pathological symptoms (for example, edema and segmentation of the jejunum during endoscopic examination);
pathological lactose tolerance test, (i.e. the presence of abnormal bacterial flora during aspiration of intestinal contents);
lack of secretory Jgd;
hypogammaglobulinemia (deficiency of one of the types of proteins in the human body - gammaglobulin);
achlorhydria (lack of hydrochloric acid in gastric juice).

Immunological methods (ELISA method for detecting the Giardia lamblia antigen) have recently been widely used all over the world for the diagnosis of giardiasis. Such test systems have very high sensitivity and specificity, and allow the simultaneous detection of both cysts and trophozoids in stool samples. Usually G lamblia is detected in 50-70% of patients after a single stool analysis. After three times analysis - in 90%.

The detection of antibodies of the total classes IgA, IgM, IgG to the antigens of lamblia (serological methods) is an indirect method of laboratory diagnosis of giardiasis. It can be used as an additional diagnostic method to determine the body's immune response to the introduction of the pathogen.

Blood for antibodies to lamblia

Blood for antibodies to lamblia can be donated not only in the laboratory of a medical institution, but also in any of the many independent laboratories.

In the case of giardiasis, enzyme immunoassay is able to determine not only the presence of the disease, but also how far the disease has gone.

If only specific IgM antibodies are detected in the blood, this means that no more than several weeks have passed since the moment of infection with lamblia. And the presence of specific IgG antibodies to lamblia antigens indicates that the invasion occurred a long time ago.

However, IgG antibodies can be detected in the patient's blood for some time (up to 2 months) and after complete recovery.

How to get tested

For the analysis, a fresh sample of the patient's feces is required. For maximum accuracy of the analysis, feces must be collected in the morning, in a special container with a preservative. Such a container must be taken from the laboratory in advance. Feces can be collected in other clean dishes, but it is important to get it to the hospital as soon as possible.

Stool collected in the evening should be refrigerated, but the likelihood of obtaining a correct test result from such a sample is reduced.

Decoding the analysis. How accurate are the results

Indisputable confirmation of giardiasis is the detection of cysts or adult motile lamblia in the feces.

Antibodies to lamblia. The accuracy of one analysis of feces for lamblia is on average 50-70%. Three times the analysis of feces collected on different days has an accuracy of about 90%. Thus, a negative result of one stool test for lamblia does not always indicate the absence of infection. For more or less complete confidence in the absence of the parasite, it is recommended to take a stool test 3-4 times with an interval of 3 days between separate analyzes.

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