Immunoglobulins E are antibodies. They are produced by plasma cells of various organs: tonsils, stomach, spleen, intestinal mucosa and respiratory tract. Immunoglobulin e IgE is able to quickly attach to the surface of mast cells and basophils of the mucous membranes and skin. Upon repeated contact with the antigen, vasoactive substances (histamine, serotonin, heparin) are released on the surface of these cells and an immediate allergic reaction is triggered. Immunoglobulins E are involved in protective anthelmintic immunity. At the Yusupov Hospital, an IgE immunoglobulin test is carried out for the purpose of diagnosis and evaluation of the effectiveness of therapy for allergic diseases, diagnosis of hyper-IgE syndrome and helminth infections, to assess the risk of developing allergic diseases in children.
The results of the study are interpreted by candidates and doctors of medical sciences, doctors of the highest category. After a comprehensive examination of patients, allergists draw up an individual treatment regimen for diseases in which there is a pathological change in the concentration of IgE immunoglobulins. To treat patients, recommendations from European and American allergists are used. Doctors prescribe to patients the most effective medications registered in the Russian Federation, which have minimal side effects.
Analysis for specific immunoglobulins E
For early diagnosis of allergic diseases and identification of the main allergens, the allergological profile of the patient is examined, the main indicators of which are analysis of specific immunoglobulins E and general immunoglobulin E.
During allergic reactions, allergens in the human body form specific immunoglobulins E. Allergens can be household, pollen, food, etc. The levels of specific immunoglobulin E in patients suffering from allergies increase sharply.
What kind of analysis is this
A test for general immunoglobulins E in the blood is used to diagnose allergies, but to search for the causative allergen, immunoglobulins E specific to it are identified. IgE, contained in free form in the blood serum, makes up 0.002% of all antibodies. When interpreting the indicators of total immunoglobulin ig e, allergists at the Yusupov Hospital take into account a number of factors:
- in approximately 1/3 of patients with atopic diseases, the level of total IgE does not exceed the norm;
- some patients with bronchial asthma have increased sensitivity to only one antigen, as a result of which their level of total immunoglobulin E may be within normal limits, while specific immunoglobulins E and skin test results will be positive;
- the concentration of total immunoglobulin E also increases with helminthic infestation, bronchopulmonary aspergillosis and some forms of immunodeficiency and normalizes after treatment;
- angioedema and chronic recurrent urticaria are not mandatory indications for determining total immunoglobulin E, since in most cases they are non-allergic in nature;
- antibodies of other classes that are specific for a given allergen may cause false negative results;
- exceptionally high concentrations of total IgE immunoglobulin may be due to nonspecific binding to various antigens.
Indications for testing for specific immunoglobulin E
An analysis for specific immunoglobulin E is prescribed by immunologists to patients who suspect the presence of the following disorders:
- allergic diseases: bronchial asthma, hay fever, atopic dermatitis, eczema, food and drug allergies;
- helminthiases.
In addition, this study is conducted to assess the likelihood of developing allergies in pediatric patients with a hereditary predisposition to this pathology.
Where is allergy testing done?
When visiting a doctor, first of all exclude the presence of dermatological and respiratory problems. For this purpose, the patient is asked under what conditions the symptoms of the disease appear.
To determine the cause of an allergic reaction, patients' blood is examined and skin samples are taken.
If symptoms of the disease are detected in a patient, a general blood test is required, including a leukocyte count. The number of leukocytes in a patient with allergies increases, but the concentration of erythrocytes and platelets does not change.
To confirm an allergy, the blood should be tested for immunoglobulins G and E. The former are involved in delayed reactions, and it takes several days from the moment of contact with the allergen to detect them. Immunoglobulin E appears a few minutes after contact. The total amount of IgE antibodies and specific IgE antibodies are of clinical significance.
The response is low, medium and high. The first indicates the complete safety of the substance. An average response suggests that the patient is better off avoiding the substance in question or limiting exposure to it. A high reaction is a sign that it is the test substance that provokes an allergic reaction.
Allergies are shown by the RAST test, which is a radioallergosorbent method. It is preferred because at the time of preparation for the study it is not necessary to give up antihistamines, so it can be used for severe cases of allergies. This method is also prescribed to determine the cause of the disease in young children.
If skin and blood tests do not show the cause of excessive sensitivity, a provocative test is performed. The technique involves applying the allergen to the nasal passages, under the tongue, or directly into the bronchi. Such diagnostics should take place in the clinic, since the patient may need resuscitation.
Tests to determine allergens are taken at a medical institution on the direction of an allergist. The doctor indicates specific irritants to which the patient may be hypersensitive.
Allergies cause discomfort, and the patient’s condition can be alleviated by stopping contact with the substance that causes such a reaction. This is possible after blood tests or skin tests. The doctor selects the appropriate method, taking into account contraindications.
Types of allergological profiles for research
The following allergological profiles can be tested in clinical laboratories:
- household allergens (panel or individual allergens - house dust, micro mites);
- animal hair or epithelium (panel or individual allergens - cat, dog hair, hamster or guinea pig hair);
- fungal allergens (panels);
- pollen allergens (panels characteristic of the patient’s place of residence);
- food allergens (individual allergens to exclude irritants from the diet);
- medicinal allergens (as prescribed by doctors).
Types of allergens
In humans, hypersensitivity is usually observed in relation to several allergens at the same time. Monoallergy is diagnosed quite rarely.
The following types of allergens are distinguished:
- food, which includes food products;
- animal origin, including hair and epidermis of cats, dogs, horses, rodents;
- pollen;
- parasitic, including worms, fungi, microorganisms;
- medicinal;
- house dust, which includes dust mites;
- chemical substances;
- inhalation
Allergies to medications are diagnosed less frequently than others, since patients often confuse this reaction with a side effect of the drug and do not consult a doctor. Allergies are triggered by blood products and vaccines containing animal protein.
The reaction to food allergens is associated with a lack of certain enzymes for digesting foods, and therefore their intolerance develops. Food allergies are also diagnosed when there is intolerance to the smell or taste of a dish.
An increased reaction to pollen is observed during flowering plants. At this time, the patient complains of a runny nose, lacrimation, and develops conjunctivitis.
Allergies to chemicals are detected through contact with household chemicals or harmful substances during work. It can manifest itself as rashes and burning, similar to a contact allergy, or asthmatic symptoms, which is typical for respiratory diseases.
Preparation for testing for specific immunoglobulin E
Adult patients are advised to avoid physical and emotional stress three days before blood sampling, and not to smoke at least an hour before the test.
Pediatric patients do not need special preparation. In order to avoid injuries and vagaries, you need to try to mentally prepare them for the fact that they will need to donate blood from a vein. To make blood sampling easier, it is advisable for the child to wear clothes with short sleeves.
The results of the analysis will be ready, as a rule, the next (working) day after the study.
Preparation
The IgE immunoglobulin test is carried out strictly on an empty stomach. For the study, nurses at the Yusupov Hospital collect venous blood, observing the rules of asepsis and antiseptics. Before the test, it is not recommended to eat food for 10-12 hours, and fatty foods and alcohol should be excluded from the diet one day before the test. You can drink clean still water.
During the several days preceding the study, patients are not given an ultrasound examination, IVs are not placed, and X-rays are not taken. They are not recommended to visit the solarium, sauna or sunbathing. 2-3 days before the study you need to stop playing sports and fitness. The IgE immunoglobulin test is carried out within 3 days. The results of the study in complex cases are discussed at a meeting of the expert council. Doctors at the Yusupov Hospital make a collective decision on further treatment tactics for the patient.
Norm of specific immunoglobulin E
The level of specific immunoglobulin, like any other indicators, can fluctuate within different limits, sometimes beyond the reference range.
Normal levels of specific immunoglobulin in children from birth to one year are values from 0 to 15 kU/l, from one year to six years - from 0 to 60 kU/l, from six to ten years - from 0 to 90 kU/l. The maximum increase in the level of this protein is observed in adolescents; from ten to sixteen years old it can range from 0 to 200 kU/l. In adults, specific immunoglobulin E levels can vary from 0 to 100 kE/l.
A qualified allergist should clarify the diagnosis based on the results of the analysis and decide on further treatment.
At the Yusupov Hospital, which is a multidisciplinary medical center, you can conduct high-quality diagnostics and complex therapy that meet modern world standards for the treatment of a wide variety of pathologies. The Yusupov Hospital employs specialists with extensive experience and high qualifications, thanks to which they are able to achieve high efficiency in the treatment of any disease. The hospital has ultra-modern diagnostic and treatment equipment that allows it to provide medical services at the highest level. The staff of the Yusupov Hospital - from nurses to doctors of various specializations - will provide high-quality and qualified medical support until the patient’s complete recovery.
You can make an appointment for a consultation with leading specialists by calling the clinic or on the Yusupov Hospital website by contacting the coordinating doctor.
Author
Norm and changes in indicators
The normal concentration of immunoglobulin IgE in newborns is considered to be up to 1.5 IU/ml, in children 1-5 years old - up to 60.0 IU/ml, 6-9 years old - up to 90.0 IU/ml, 10-15 years old - up to 200 .0 IU/ml. Normally, the level of immunoglobulin IgE does not exceed 100.0 IU/ml. Total immunoglobulin e IgE may be high in patients receiving penicillin antibacterial drugs, but decreased when taking phenytoin.
An increase in the level of immunoglobulin IgE is observed in patients suffering from atopic allergic diseases (allergic rhinitis, atopic bronchial asthma, atopic dermatitis, allergic gastroenteropathy). Immunoglobulin IgE may be high in patients with the following diseases:
- anaphylactic reactions (systemic anaphylaxis, angioedema);
- allergic bronchopulmonary aspergillosis;
- helminthiasis;
- hyper-IgE syndrome (Job syndrome);
- Wiskott-Aldrich syndrome;
- selective IGA deficiency;
- thymic aplasia (DiGeorge syndrome);
- IgE myeloma.
The concentration of immunoglobulin Ig e increases in the case of graft-versus-host disease. A decrease in the level of immunoglobulin IgE may indicate a significant deterioration in the function of the immune system, the presence of immunodeficiency or myeloma.
Make an appointment with an immunologist at the Yusupov Hospital by calling. The doctor will conduct an examination and prescribe an IgE immunoglobulin test. After discussing the results of the study, treatment will be prescribed.
Author
Vladimir Vladimirovich Kvasovka
Deputy General Director for Medical Affairs, therapist, gastroenterologist, Ph.D.
Analysis and norm for a child
There are five types of immunoglobulin in the human body: A, E, D, M and G.
All of them are designed to perform a variety of functions:
- prevent recurrent disease;
- neutralize toxic substances;
- protect against foreign organisms trying to penetrate.
In medicine, there is a norm of immunoglobulin E, which differs somewhat depending on various factors and age:
- From birth to three months – 2 units/ml.
- Up to six months – no more than 10 units/ml.
- Up to a year - up to 20 units/ml.
- Up to five years – up to 50 units/ml.
- Up to fifteen years – from 16 to 50 units/ml.
When there is no fight against harmful bacteria and infection in the body, the content of this substance should be minimal.
The amount of immunoglobulin may change even depending on the time of year. For example, in May it reaches the maximum possible amount, but in December the situation is completely different.
This substance is responsible for immediate allergic reactions of the body, as well as anthelmintic immunity.
Immunoglobulin E is localized in the layer under the mucosa, which is in contact with the environment, this is:
- tonsils;
- skin covering;
- respiratory tract;
- eyes;
- adenoids;
- gastrointestinal tract.
The analysis is prescribed by specialists for the following diseases:
- food allergies;
- asthma;
- eczema;
- bronchitis;
- dermatitis.
But it is also prescribed in the following cases:
- diagnosis of immunodeficiency;
- allergy diagnosis;
- in the period before the scheduled operation;
- after surgery;
- presence of parasites;
- suspected autoimmune diseases;
- for lung pathology in children;
- if you suspect cancer.
Blood is taken only in the morning from a vein and exclusively on an empty stomach. The day before, you should stop eating fried and fatty foods, and also limit physical activity. If a child is prescribed medications, the specialist should be notified of this fact, since some groups of medications have adverse reactions that affect the content of immunoglobulin e.
An interesting fact is that in people suffering from allergies, the level of immunoglobulin E is constantly high, regardless of how long ago they have been in contact with the allergen.
As for pregnant women, immunoglobulin E is formed independently in the fetus around the eleventh week. After the baby is born, its amount gradually begins to increase until adolescence, but in old age, immunoglobulin E gradually decreases.
Disadvantages of skin testing
To determine the cause of allergies, a method is used to study skin tests. Within a few minutes, the test reveals a substance to which the patient is highly sensitive. This is evidenced by redness and swelling on the patient's skin. However, it should be taken into account that such a reaction may occur in those with sensitive skin.
Skin testing is carried out in several ways:
- Scarification test. The technique involves applying several allergens to the skin, after which it is scratched with a scarifier.
- Prick test. It differs from the previous method in that a needle is inserted into the site where the allergen is applied, making superficial punctures.
- Application test. The method involves attaching a patch containing allergens to the skin. The condition of the skin is assessed after two days.
Of these methods, the safest for the patient is the last test, since it does not involve damage to the skin. It is worth noting that with each of the described methods, only the top layer of skin should be damaged so that the allergen does not enter the blood.
With skin testing, a maximum of 15 potential allergens can be tested at a time, otherwise the patient may have a severe reaction. Doctors, using more allergens, diagnosed angioedema in patients.
Contraindications to skin testing are:
- presence of lesions on the skin;
- pregnancy and lactation;
- cases of anaphylactic shock;
- regular use of antihistamines, refusal of which is impossible even for a short time;
- age under 5 and over 60 years;
- use of hormonal drugs;
- exacerbation of allergies;
- elevated temperature;
- problems with the gastrointestinal system and heart.
