Total immunoglobulin E blood test. Increased immunoglobulin E - what does this mean? Immunoglobulin M is elevated, what does this mean?

Immunoglobulins are specific protein compounds that can selectively bind to a certain type of molecule and cause a specific immune response in the body.

Immunoglobulins (or antibodies) are part of the immune system. There are several classes of antibodies, each of which causes its own specific reaction depending on the antigen to which it binds. Immunoglobulin E is classified as an antibody that provokes allergic reactions.

Immunoglobulins play an important role in the body. They bind to certain types of foreign substances and signal to the immune system, resulting in an immune response. Each immunoglobulin has its own spectrum of antigens to which it reacts.

High immunoglobulin E in the blood can be found in allergy sufferers and children whose parents suffer from various types. That is, allergens are antigens for IgE.

Immunoglobulin E is found on the surface of B lymphocytes. It is located in the membrane and when allergens enter the body, it binds to them, releasing various active substances into the blood that provoke an immune response. Typically, this type of antibody provokes the most common allergic reactions such as skin rash, itching, swelling, shortness of breath and cough.

It is mainly found in the skin and mucous membranes, which most often come into contact with the external environment: in the tonsils, lungs, mucous membranes of the throat and nose, as well as. It circulates in the blood for about 2-3 days and dies off; it lives longer in the skin - up to 2 weeks.

Immunoglobulin E begins to be produced by the body during fetal development, in the first trimester of pregnancy. After the birth of a child, the amount of IgE in the blood increases until adolescence, and in old age it decreases slightly. Plasma cells are responsible for the production of antibodies.

Diagnostics and norm

The procedure for drawing blood to test the level of immunoglobulin E

Normally, the level of IgE in the blood is low, but the level may vary depending on age. For example, in children under one year of age the norm is from 0 to 15 IU/ml; by 6 years the upper limit of the norm increases to 60 IU/ml. By the age of 16, the norm rises to 200, and then by maturity it decreases again to 100 IU/ml.

The diagnosis of immunoglobulin E in the blood is. A similar analysis is prescribed to young children whose parents suffer from allergies, to check the likelihood of an allergic reaction, if helminthic infestations are suspected, to check the effectiveness of allergy treatment.

As a rule, the analysis is prescribed for atopic conditions such as dermatitis, asthma, rhinitis, and Quincke's edema.

Immunological analysis has some features:

• The analysis does not require special preparation, but it is recommended to take it in the morning on an empty stomach, and before that, abstain from fatty foods for 1-2 days. This is necessary to ensure that the blood serum does not become cloudy and clot prematurely.
• There is no need to give up antiallergic medications. Taking antihistamines does not affect the test results, but other drugs may affect the blood serum, so you should inform your doctor about taking any medications before taking the test.
• When taking the test, it is taken into account that not all atopic diseases and allergic reactions are accompanied by an increase in the level of immunoglobulin E in the blood.
• The analysis takes into account the level of both total and specific immunoglobulin E, since the indicators may differ. For example, in asthma, general immunoglobulin may be normal, but specific immunoglobulin may be increased. This is due to the fact that only one specific allergen causes an immune reaction.

More information about the blood test for immunoglobulins can be found in the video:

Detection of an increased level of IgE to any allergen still does not prove that this allergen caused atopic manifestations. The diagnosis is made only after further examination. And also a low level of immunoglobulin in the blood does not indicate the absence of allergic reactions.

Reasons for the increase

The diagnostic value of an immunological blood test in determining the level of IgE is quite high, but it is impossible to unambiguously interpret the result based on a blood test alone. This is due to the fact that the level of immunoglobulin E can change for various reasons. For example, immunoglobulins of other classes can suppress the production of IgE.

The reasons for the increase in immunoglobulin E may be the following:

Even after an immunological blood test, an allergy cannot be diagnosed solely on the basis of an elevated level of immunoglobulin E in the blood. It is recommended to undergo skin tests and other tests to confirm the diagnosis.

The level of immunoglobulin E decreases with adequate treatment of the disease causing the increase. Therefore, the analysis is often retaken several times during and after the course of treatment.

Treatment methods directly depend on the identified disease:

• Antihistamines. They are prescribed for an allergic reaction. If the allergy is seasonal, then it is necessary to select medications for long-term use. Antihistamines block those receptors that respond to the allergen itself. These drugs include Diazolin, Loratadine, Suprastin, Zodak, Clemastine, Cetirizine.
• Local medications. In the treatment of allergies, various local preparations are used: ointments, creams, solutions, hormonal sprays, eye drops, etc. They significantly relieve allergy symptoms and reduce the risk of complications.
• Immunotherapy. This is a method of treating allergies, not relieving symptoms. Immunotherapy allows allergy sufferers to live for a long time without exacerbations. However, this treatment method is recommended exclusively for people with IgE-related allergies. It consists of gradually introducing increasing doses of allergens into the body.
• Anthelmintic drugs. These are drugs that destroy adult helminths, but do not affect their eggs. After a couple of weeks, the course of anthelmintic drugs must be repeated. Similar medications include Pyrantel, Albendazole, Levamisole.
• Diet. For helminthic infestations, it is recommended to adhere to proper nutrition and avoid foods that are strong allergens (honey, citrus fruits, flavorings).

Treatment methods should be selected by a doctor. In the case of allergies, you need to remember about prevention. It is important to identify all possible allergens and avoid contact with them.

A blood test for immunoglobulin E is the main indicator of an allergological profile, allowing one to identify diseases of an allergic nature and differentiate them.

Blood test for immunoglobulin E: general information

This class of immunoglobulins was first described in the 1960s, due to its relatively low concentration (20-100 IU/ml, which is about 0.2% of all serum immunoglobulins) in blood serum compared to other immunoglobulins. According to WHO calibration standards, one international unit (IU) in a blood test for immunoglobulin E is 2.4 ng (that is, 2.4 * 10-9 g).

Immunoglobulins class E (reagins) by their structure they are gamma globulins, which are produced by B lymphocytes. They, like all immunoglobulins, have 2 light (L) and 2 heavy (H) chains in their structure. Differences in the structure of heavy chains determine certain biological functions of immunoglobulins of different classes. Reagins (Ig E) have the ability to attach to the cell surface of basophils and mast cells using specific receptors. This plays a major role in the development of type I (immediate) hypersensitivity reaction. Upon subsequent contact of reagins with the allergen (already on the surface of these cells), vasoactive substances (serotonin, histamine, etc.) are released and clinical manifestations of allergy develop. Immunoglobulins E are more associated with atopic diseases such as urticaria, allergic rhinitis, atopic dermatitis, and bronchial asthma.

Diagnostic value of a blood test for immunoglobulin E

This research method allows you to:

• assessment of the risk of an allergic reaction in children (Ig E level as a prognostic indicator);
• assessment of the immune status of the body as a whole;
• diagnosis of helminthic infestations;
• differential diagnosis of hypersensitivity reactions among diseases with similar symptoms (dermatitis, other diseases of the upper respiratory tract);
• assessment of the effectiveness of treatment of allergic diseases, as well as pulmonary aspergillosis;
• diagnosis of some immunopathological diseases;
• objective assessment of sensitization to a specific allergen.

Accordingly, indications for a blood test for immunoglobulin E may include allergic diseases (primarily atopic), suspected helminthic infestation, autoimmune diseases, immunodeficiency conditions, suspected IgE myeloma, bronchopulmonary aspergillosis.

Features of the analysis

To test blood for immunoglobulin E, venous blood is taken on an empty stomach, several weeks after stopping medication (if possible). There is an analysis for and for specific ones (for certain inhalation, food, household, medicinal, chemical and other allergens). Thus, total immunoglobulin in patients with bronchial asthma may remain within normal limits, but one of the specific reagins will be elevated.

Interpretation of blood test results for immunoglobulin E

The normal level of total Ig E in the blood serum varies depending on age. So, in children under one year of age the norm is 0-20 IU/ml, up to 5 years - 10-50 IU/ml, up to 14 years - 20-60, in adolescence it can increase to 100-200, and in adults - 20- 100 IU/ml.

A decrease in Ig E levels is observed with:

• hereditary or acquired hypogammaglobulinemia;
• ataxia-telangiectasia due to a defect in the T-lymphocyte unit;
• primary or secondary immunodeficiencies;
• sex-linked hypogammaglobulinemia.

It should also be remembered that the indicated reference (normal) values ​​for the level of immunoglobulin E are determined for Europeans and cannot be used for persons living in regions endemic for helminth infections.

In adults, determining the concentration of immunoglobulin E in blood serum has less diagnostic value than in children. Elevated levels of immunoglobulin E are detected only in 50% of patients with atopic bronchial asthma. The highest concentrations of immunoglobulin E in the blood are observed with hypersensitivity to a large number of allergens in combination with bronchial asthma, atopic dermatitis and allergic rhinitis. In case of hypersensitivity to one allergen, the concentration of immunoglobulin E may be within normal limits.

Allergic bronchopulmonary aspergillosis is accompanied by a significant increase in the content of immunoglobulin E in the blood. Its concentration is increased in almost every patient with allergic aspergillosis during the period of acute pulmonary infiltration. A normal immunoglobulin E level in patients with active lung disease excludes the diagnosis of aspergillosis.

Determination of immunoglobulin E is important for diagnosing a rare disease - hyper-IgE syndrome. It is characterized by an increase in the concentration of immunoglobulin E in the blood to 2000-50,000 kU/l, eosinophilia, pronounced urticaria and hyperemia to inhaled allergens, pollen, food, bacterial and fungal allergens. Bronchial asthma is not typical for this syndrome.

When assessing the results of determining total immunoglobulin E, it should be borne in mind that in approximately 30% of patients with atopic diseases, the concentration of immunoglobulin E may be normal.

When is immunoglobulin E low?

Concentration of total immunoglobulin E in blood serum under certain pathological conditions

When diagnosing an allergy, it is not enough to state an increase in the concentration of total immunoglobulin E in the blood. To search for the causative allergen, it is necessary to identify specific antibodies of the immunoglobulin E class. Currently, laboratories are able to determine allergen-specific immunoglobulin E in serum to more than 600 allergens that most often cause allergic reactions in humans. However, the detection of allergen-specific IgE (to any allergen or antigen) does not yet prove that this particular allergen is responsible for the clinical symptoms. Interpretation of research results should be carried out only after comparison with the clinical picture and data from a detailed allergic history. The absence of specific immunoglobulin E in the blood serum does not exclude the possibility that an IgE-dependent mechanism is involved in the pathogenesis of the disease, since local synthesis of immunoglobulin E and sensitization of mast cells can occur in the absence of specific immunoglobulin E in the blood (for example, with allergic rhinitis). Antibodies of other classes that are specific for a given allergen, especially the immunoglobulin G class, may cause false-negative results.

Immunoglobulin analysis is an essential element of differential diagnosis. Based on research results, doctors identify allergic diseases and inflammatory processes. A special table shows the optimal values ​​for each age.

It is important to know what immunoglobulin E shows. The norm in children differs at different periods of life and depends on the time of year. Why are the indicators changing? What does increased and decreased IgE levels mean? How to treat? The answers are in the article.

Immunoglobulin E: what is it?

A special protein is found on the membranes of plasma cells. The substance is present in small quantities in the blood plasma; during an acute immune response, the active release of serotonin, histamine, and heparin occurs, and the number of antibodies increases sharply. The task of lgE is to destroy foreign information that has entered the body. Antibodies produced during an immune reaction lead to the death of antigens.

Immunoglobulin E is the cause of a type 1 lightning reaction, in which life-threatening signs appear (pronounced swelling of the tissues and larynx). It is the IgE level that allows you to determine your susceptibility to allergic diseases. Immunoglobulin E is also involved in the formation of anthelmintic immune defense.

On a note:

• the main physiological function of lgE is to protect the mucous membranes and skin from external influences by activating mast cells and plasma factors;
• the substance is produced by a small part of plasma cells;
• in the normal state, the level of immunoglobulin E is up to 0.5 mg/l, no more;
• with increased sensitization to many types of irritants and confirmed allergies, the IgE level increases;
• in some diseases the indicators exceed the permissible values ​​by 5-7 times or higher. Average values ​​for bronchial asthma are from 120 to 1200, for atopic dermatitis - from 80 to 14000, for allergic rhinitis - from 120 to 1000 kE/l.

Norm indicators in children

The table shows the values ​​of an important indicator of allergic inflammation:

It is important to know: analysis of the IgE level is the main, but not the only element of diagnosis. The doctor analyzes the clinical signs of the disease and specifies the duration of the manifestation of negative symptoms. To confirm the diagnosis and clarify the type of allergen, an immunoblotting reaction, comparison of the results with a pediatric allergen panel, or skin testing is required.

IgE immunoglobulin is elevated: reasons

In most cases, an excess of total immunoglobulin E in the blood serum indicates the development of allergic diseases. The doctor takes venous blood and compares the results with the table value.

It is important not only to clarify the level of allergy indicator, but also to find out the clinical picture of the disease and study negative symptoms in detail. Increased levels develop not only against the background of hypersensitivity of the body after contact with an allergen, but also with other types of diseases.

A high level of lgE indicates the development of the following diseases of an allergic nature:

• bronchopulmonary aspergillosis of allergic origin;
• atopic;
• negative reaction to certain foods;
• drug allergies;
• allergic gastroenteropathy.

Increased levels in the absence of signs of allergy are one of the signs of the development of the following diseases:

• thymic aplasia;
• helminthic infestations;
• myeloma;
• hyper-lgE syndrome.

On a note! Based on the results of research, doctors have found that with food allergies, the body’s sensitivity to microparticles of pollen from certain plants, the level of immunoglobulin E increases more actively than with a pronounced reaction to mold spores and house dust. With a negative response to one type of allergen, the indicators often remain within the reference values ​​or are slightly increased.

Decreased results: probable reasons

Deviation from the norm is possible with the following diseases:

• Louis-Bar syndrome;
• hypogammaglobulinemia of hereditary nature;
• some types of neoplasms.

How to prepare for the test and donate blood

Accurate test results make it possible to diagnose many diseases. Before taking blood, the doctor will explain how to act correctly so as not to blur the picture of the pathology. Parents should know what reasons prevent the true result from being established.

How to prepare for an immunoglobulin test? Three important rules:

• 4-5 days before the test, adjust your diet: give up fried, salty, spicy, steam, stew, bake. Basic Requirement- dishes should not irritate the intestinal mucosa.
• A week before the test, penicillin antibiotics are discontinued: potent drugs often increase lgE levels. Avoidance of the use of phenytoin is mandatory: this substance often underestimates immunoglobulin E levels.
• To confirm or refute the development of an allergic reaction, donate blood from a vein strictly on an empty stomach. Drinking water or any other type of liquid is also prohibited: the results will be inaccurate.

It sometimes takes a lot of time to clarify the diagnosis and identify the allergen. If you suspect a need, during which a certain product is excluded, the reaction is observed, after a while the supposed irritant is again included in the menu, and the body’s response is monitored.

Certain actions help return the lgE level to normal:

• identifying the allergen, stopping contact with the irritating substance, refusing certain medications. If you are hypersensitive to components or animal fur, more careful care of your pet and home will be required;
• To prevent skin reactions, disruption of the gastrointestinal tract, damage to the conjunctiva and nasal mucosa, children should consume less frequently. In case of an acute reaction to certain types of food, you will have to exclude some items from the menu;
• Strengthening the immune system is an essential part of allergy prevention. The level of immunoglobulin E will be normal with a decrease in sensitization of the body. Well-known pediatrician Dr. Komarovsky recommends giving babies and older children calcium gluconate. The product, proven over the years, has a positive effect on the condition of capillaries and increases the defenses of the growing body;
• elements of prevention: walks in the fresh air, moderate physical activity, healthy sleep, varied diet, vitamin and mineral complexes.

If immunoglobulin E levels deviate from the norm, it is important to find out what diseases are causing the level of allergic inflammation indicator to be reduced or increased. For differential diagnosis, the patient should consult an immunologist, allergist, or infectious disease specialist. To correct IgE levels, doctors prescribe a set of preventive measures. If you are hypersensitive to irritants, it is important to limit or eliminate contact with allergens.

Find out everything you need to know about the blood test for immunoglobulin E after watching the following video:

Immunoglobulins are complex and specific molecules in the human body. Experts have studied five classes, each of which performs its own tasks. Immunoglobulin E is a representative of one of them. It began to be actively studied in the sixties of the last century. Since then, almost all laboratories in the world have used it in their work. We will discuss in detail what IgE is, what classes of this substance exist, what its normal level is in the body, and the reasons for deviations from it in the article.

Structure of matter

Immunoglobulin class E: structure, classes of substance, blood levels

The body begins to produce class E immunoglobulins in utero. Already in the first trimester of pregnancy, this substance is detected in the blood of the fetus. Its level invariably increases throughout life, with decreased activity recorded in old age. The functioning time of Ig E is 2-3 days; on mucous membranes it “lives” longer (up to 2-3 weeks).

Specialists (allergists, immunologists) distinguish two classes of this substance:

• Common immunoglobulin E is responsible for the development of type 1 allergic reaction (immediate). When interacting with a pathological agent, a massive release of active substances (histamine, serotonin) occurs into the blood. A common outcome of such a reaction is anaphylactic shock or urticaria.
• Specific immunoglobulin E was isolated not so long ago, but today it is used by laboratories, performing a number of allergy panels. What does it mean? It has become possible to carry out by dividing allergens into food, household, plant, animal and others. This helps in the differential diagnosis of the type of allergy and in identifying the specific causes of the reaction.

Attention! The study begins with determining the total level of immunoglobulin e (ig e), and if it shows a deviation, or there are clinical symptoms, they begin a detailed examination.

The study is performed using the ELISA method (enzyme-linked immunosorbent assay). The measurement is made in IU/ml (international units per milliliter). The normal levels of total IgE depending on age are as follows:

• from 0 months to 3 months – 0-2;
• 3-6 months – 3-10;
• 1 year – 8-20;
• up to 5 years – 10-50;
• over 15 years old – up to 60;
• in adult men and women – up to 100.

Changes in total immunoglobulin e (or Ig E total) in a blood test can be either upward or downward. Identification of any deviation from the norm requires further clarification of the reasons.

Rules for preparing for analysis and indications for performing analysis

How to get tested? For the study, the laboratory technician takes venous blood, and its serum will be studied. No specific preparation is required. Preparation for analysis involves:

• Refusal to eat 10-12 hours before blood sampling. It is better to refrain from fatty foods so that the serum does not clot and chyle does not occur (its cloudiness);
• Abstinence from alcohol and smoking;
• Limiting physical activity;
• The preferred time for testing is in the morning after sleep to avoid a false increase in the level.

You should not get tested for ige during an active viral infection. It is worth telling your doctor about the medications you are taking, regardless of which group they belong to. Refusal from antiallergic (antihistamine) drugs is not necessary. The study takes on average 2-3 days - it all depends on the specific laboratory. Only a doctor deciphers the analysis!

Indications for prescribing a blood test for Ig e are most often determined by a therapist or pediatrician. More details about the analysis and indications for it in the video:

Interestingly, the highest level of Ig E is observed in the spring, and the lowest immunoglobulin is in the winter. This is directly related to plant flowering and increased exposure to ultraviolet rays.

Reasons for increased serum immunoglobulin in adults

If the IgE level is normal, this is good, but deviations require detailed study. If immunoglobulin E in the blood is elevated, it is imperative to find out the reasons. Since the high level may be based on trivial processes or serious diseases, which without timely treatment can cause serious complications.

From the list it is clear that diseases from different groups are responsible for high levels of IgE in the blood, some of them are life-threatening.

Reasons for increased immunoglobulin class e in children

Until the age of five, a child’s immune system is formed. An increase in the level of total immunoglobulins is not always detected in the presence of clinical symptoms. But at the same time, their high level reflects the specificity and high probability of the pathological process. Deviation from normal values ​​in children causes:

• intolerance to food components (lactose intolerance, celiac disease).
• Seasonal allergies.
• Bronchial asthma.
• Genetic diseases: Wiskott-Aldrich syndrome, DiGeorge syndrome and others. They are characterized by frequent bacterial infections, retardation in physical and mental development, and the development of secondary cancers. Children suspected of having these syndromes undergo additional genetic tests, which are done by special laboratories and help provide an accurate explanation of the cause.
• Hyper-Ig E syndrome is a deviation in the functioning of the immune system. It is characterized by an increased level of general ige and a specific clinical picture: recurrent sinusitis and rhinitis, pneumonia, infectious damage to the skin and mucous membranes. Autoimmune connective tissue diseases and bone fractures develop secondarily.

Remember! If there are alarming symptoms and serum immunoglobulin levels increase, a comprehensive examination of the child is required. And doctors of different specialties (pediatricians, hematologists, geneticists, allergists) who are responsible for the child’s health should decipher the tests.

Reduced immunoglobulin E levels

A decrease in Ig E in the analysis is less common. Most often it is lowered due to genetic diseases:

• A hereditary pathology associated with a low level of gamma globulins in the blood is hypogammaglobulinemia.
• Ataxia-telangiectasia: Serum immunoglobulin levels are reduced due to damage to T lymphocytes.

A large group of diseases that cause low levels of serum immunoglobulin include primary and secondary immunodeficiencies. Primary ones are usually associated with genetic disorders, while secondary ones are acquired. To clarify them, further examination is required (for example, an HIV test, a general blood test).

Methods for correcting immunoglobulin E

We looked at what a blood test for immunoglobulin e is, the reasons why this indicator changes, and the norms for its content. The method of treatment depends solely on the cause of the change.

How to reduce the rate:

• Follow a diet. In case of food allergies, diet correction is the basis of methods that reduce clinical manifestations. Inappropriate foods that increase the level of Ig in the blood, as well as all fatty, fried, processed foods and fast food, are excluded from the diet.
• Spend more time outdoors.
• Avoid smoking (including passive smoking).
• Avoid contact with the allergen. If the study showed a reaction to animal hair or household dust, it is enough to remove them from your home to normalize the increased immunoglobulin.
• Carry out detoxification. Sorbents are used for this. These drugs bind toxins and remove them from the body, helping to restore normal Ig levels.
• Take antiallergic drugs that block allergen receptors. To lower immunoglobulin, they should be selected individually. First generation drugs (Diazolin, Suprastin) are effective, but taking them increases drowsiness. Second generation drugs (Loratadine) are more convenient to take, they work in low concentrations, and are less likely to cause side effects;

• Take a course of anthelmintic therapy if a helminthic infestation is detected. The dose of the drug and the duration of administration are prescribed by the doctor. After the correct course of treatment, the level of total immunoglobulin returns to normal.
• Take a course of immunotherapy. This method of reducing serum Ig is specific. It is based not on suppressing symptoms, but on influencing the cause. Drugs are prescribed only after a comprehensive examination and an accurate diagnosis. Otherwise, there is a high probability of complications.
• Use local medications. It does not help reduce total Ig E in the blood serum, but reduces inflammatory manifestations on the skin and restores their integrity. They use ointments, creams, balms that contain an antihistamine or hormonal component.

During treatment, you need to monitor how the patient responds to it. This can be done by taking tests once a month. List of studies:

• general and detailed blood test;
• blood chemistry;
• antibodies to immunoglobulin class E to evaluate what the analysis shows.

Over time, tests will have to be repeated less often, and blood counts will normalize. In most cases, it is possible to achieve lower Ig levels. But the prescription and control of therapy should be entrusted to a doctor.