What allergens do skin tests. Why is it prescribed and how are skin tests for allergens performed? False results: causes

The term "allergy tests" or "allergy tests" refers to 4 types of tests:

skin test,
blood test for determination general level immunoglobulin E,
blood test for the determination of specific antibodies,
provocative tests.

Results from one or two of these tests are required to make an accurate diagnosis. The examination begins with skin tests. In the presence of contraindications, they resort to a safer diagnostic method - a blood test for antibodies. A provocative allergen test is used only in extreme cases: if there are discrepancies between the results of studies already conducted and the patient's medical history (for example, a survey shows that the patient is allergic to birch pollen, but skin tests do not confirm this).

Allergy to various substances most often manifested by the same symptoms. It is difficult to determine the cause of an allergy without resorting to special skin tests, more commonly called allergy skin tests. This method is the most common in allergology, and is used to establish an accurate diagnosis.

Allergy tests are carried out for diseases such as:

bronchial asthma, manifested by recurring signs of suffocation as a result of bronchial spasm when exposed to allergens;
allergic dermatitis, characterized by rashes, redness and itching;
hay fever or pollen allergy, which is manifested by rhinitis, conjunctivitis, sneezing and runny nose;
food allergy, which is characterized by skin rashes, redness and itching.

How are skin tests done?

Skin tests for allergens are scarification, with skin piercing (prick tests) and intradermal. In the first two cases, the procedure is quite simple. On the skin of the patient's back or forearm, the doctor applies solutions of "interested" allergens - no more than 15-20 per procedure. Under the drops, using a special plate, scratches are made (scarification method) or shallow injections with a thin needle (prik method). It doesn’t take long to languish in ignorance - the doctor evaluates the results of the samples in 20 minutes.

Dermal allergic tests do not carry out:

during an exacerbation of any chronic disease(allergies included)
during acute infectious diseases,
children under 3 years old,
pregnant and lactating women.

In addition, it is not recommended to resort to this research method for women in the early days. menstrual cycle. Due to hormonal changes occurring in the body, test results may be unreliable. In order to take an allergy test, the patient is asked to prepare in advance:

2 weeks before the procedure, stop taking internal antihistamines,

stop using anti-allergic ointments for a week.

Skin tests are necessary for and accurate diagnosis, the number of which in Lately steadily increasing among both children and adults. The reasons for this are the difficult environmental situation, the use of low-quality food products with chemical additives, a genetic predisposition, and a sedentary lifestyle.

To prescribe adequate treatment, it is necessary to accurately determine which substances cause non-standard reactions in the body. This is found out by the method of conducting various: direct and indirect, qualitative and quantitative. All of them are done in an identical way: by direct contact of the patient's skin with a potential irritant. Testing is possible only during remission, when the patient has no signs of an allergic disease.

The doctor gives a referral for skin-allergic tests for the following allergic manifestations:

Allergic rhinitis or conjunctivitis - conditions characterized by redness and pain in the eyes, lacrimation, profuse rhinitis.
Food allergies with itchy eruptions on the skin.
Bronchial asthma with shortness of breath, shortness of breath, suffocation.
Allergic dermatitis with red rashes and itching.
Drug allergic dermatitis is a reaction of the body to certain medications.
Seasonal pollen allergy with constant sneezing, runny nose and nasal congestion.

Skin allergy tests are special method diagnostics, for which today more than 3 thousand drugs are used, and their number is constantly increasing. Each of the diagnostic tests contains an irritant that can potentially cause an allergic reaction. For their production, pollen of some plants, particles of animal hair, dust, dietary fiber, artificial and chemical substances, cells of fungi, mites, bacteria. There are several ways to conduct such tests.

Types of skin tests for allergies

Scarification tests have been used in traditional medicine for a long time, but still remain one of the most reliable. The procedure is carried out like this:

the skin on the inside of the arm is wiped with a disinfectant solution (from the wrist to the elbow);
samples of probable irritants are applied dropwise to the skin of the hand;
under each drop, the skin is slightly scratched with a special metal scarifier (disposable tool, sterile);
ask the patient to keep his hand motionless for 20 minutes so that the drops of the samples do not spread and mix with each other.

At the end of this time, the doctor determines which of the samples has a reaction in the form of a blister or discoloration of the skin.

Approximately the same technology is used for prick tests. The only difference is that after applying the test drops, the skin on the hand is not scratched, but pierced with a needle.

The most modern and non-invasive of the existing methods of skin tests is the application. For it, ready-made diagnostic tools with already applied allergens are used. Each strip can contain up to ten different allergens.

The test is carried out as follows:

clean a large area of skin (most often on the back) and stick test strips on it with adhesive tape;
samples cannot be taken for two days (you can’t take a shower either);
after 48 hours, the strips are removed and the results of the samples are evaluated.

But such a long time is not always required for effective diagnosis, it all depends on the allergen. After deciphering both primary and late samples, the patient is given a form with the results, on which, next to each probable allergen, there should be:

positive;
weakly positive;
doubtful;
negative.

Each study may include the identification of the body's response to 10-15 allergens. When conducting a quantitative test (determining the degree of susceptibility to a certain type of stimulus), it is possible to use the same substance, but in different concentrations.

For a more accurate diagnosis, modern medical techniques make it possible to determine antibodies to the pathogen based on the results of a special blood test in addition to skin tests.

Direct, indirect and provocative skin tests

Direct allergological tests are a survey technology aimed at diagnosing a specific disease. In direct tests, the allergen comes into contact with the skin as a result of damage to the epidermis or without it by applying an irritant drop containing this allergen (scarification, prick tests, applications).

Indirect tests are the subcutaneous injection of an irritant and the subsequent taking of a patient's blood test to determine the amount of antibodies. Based on the results, the type of allergic reaction is determined.

Provocative reactions include the Prausnitz-Küstren reaction, when the patient's blood serum is injected into a healthy person. After 24 hours, the level of antibodies in the skin is fixed, and then the allergen is applied to the same area. The use of this technology is strictly limited, since it always leaves the possibility of infection of the patient in the event of a latent infection in the donor. The need for provocative tests arises if the data of the anamnesis and the tests performed do not match.

The choice of sample type depends on the disease, the expected level of sensitivity, the type of allergen, and the reactivity of the epidermis.

Significantly reduces reactivity, therefore, before testing, it is necessary to refrain from using them for a week.

Allergy skin tests: preparation and contraindications

Preparation for the procedure includes monitoring the patient's condition in order to accurately determine the time of the last allergic reaction, after which at least 30 days must pass. You should always be prepared for the fact that an emergency situation may arise during the test in case of an unforeseen reaction to the drug. Therefore, such samples should be taken only in medical institutions under the supervision of medical staff (despite the fact that test strips can be freely purchased at pharmacies).

The procedure itself is painless and minimally invasive, so before it is carried out, you need to calm down and tune in positively. The result of the test is usually issued after 20 minutes, several hours or two days (depending on the allergen being tested).

Allergy skin tests are contraindicated for:

any infection;
exacerbation of chronic diseases;
taking hormonal drugs;
taking antihistamines and sedatives;
a time period less than 30 days since the last allergy exacerbation.

A relative contraindication is age over 60 years and pregnancy. After subcutaneous exacerbation tests and side effects are extremely rare, but they cannot be completely ruled out. The most severe of these is anaphylactic shock, the possibility of which should always be remembered and the necessary precautions taken.

Skin tests for allergens are a highly informative method for determining the irritant in case of hypersensitivity of the body. The technique is simple and effective, with minimal discomfort for the patient.

It is important to know the indications and contraindications for scarification tests, prick tests and special applications. The rules for preparing for the study, the course of the procedure, the types of reactions, the results are described in the article.

Skin tests: what are these tests

The technique allows you to determine the type of allergen, the type of negative reaction:

when the allergen comes into contact with the skin, it interacts with mast cells;
local allergic signs occur after the penetration of the irritant into the wound on the skin, with the release of serotonin and histamine;
in the area where the irritant is applied, which is dangerous for the patient, the epidermis turns red, itches, papules often appear, the place of the scratch, application or injection swells;
according to the results of the appearance of allergenic foci, doctors establish the types of irritants, contact with which will have to be excluded.

Mandatory elements of skin tests are solutions and extracts of allergens of various kinds. Doctors use glycerin and histamine to determine whether a test is correct. The reaction to histamine is manifested in most cases, the absence of even a weak response on the skin indicates possible errors in skin tests. To apply irritants, use a needle, lancet or tampon applicator.

When are studies ordered?

Indications for skin tests:

(hay fever);
intolerance to certain products and substances in the composition of food (lactose, gluten);

Contraindications

Doctors do not test in the following cases:

infectious diseases with a severe course: bronchitis, tonsillitis, pneumonia;
the patient is diagnosed with AIDS or autoimmune pathologies;
high risk of anaphylactic reactions;
lactation period;
decompensated stage of asthmatic disease;
pregnancy;
a malignant tumor was detected;
exacerbation of allergic symptoms;
mental disorders.

On a note! There are relative and absolute contraindications. In some conditions and diseases (pregnancy, tonsillitis, pneumonia, relapses of allergies), even the minimum dose of an irritant cannot be administered, but after recovery or the birth of a baby, studies are allowed. With absolute contraindications, other diagnostic methods are used, for example, a safe, highly informative blood test for antibodies (food allergen panel).

Types of testing

To identify allergens, doctors conduct several types of testing:

scarification tests. On the forearm, the doctor applies irritant particles, with a needle or lancet makes small scratches;
application tests. A safe method does not require even minimal damage to the epidermis: the doctor applies a swab moistened with an allergen solution to the body;
prick tests. The health worker applies a drop of irritant to the skin, then gently pierces the testing area with a special needle.

What are direct and indirect samples

Allergists conduct certain types of research involving the upper layer of the epidermis in the process. The methods are effective in diagnosing allergic diseases, clarifying the diagnosis or type of irritant.

Features of skin tests:

direct allergy testing. The examination is carried out to diagnose diseases that develop with intolerance to certain substances. During direct tests, a possible allergen and the epidermis are in close contact: applications, scarification tests, prick tests are carried out;
indirect skin tests. The technique was developed to determine the type of allergic reaction. First, a subcutaneous injection of the alleged irritant is carried out, after a certain period, the doctor prescribes a venous blood sampling to detect the level of antibodies;
provocative tests. The technology is used only in case of low informativeness of other methods or false-positive/false-negative test results. The method allows you to clarify the diagnosis if the data of previous tests and anamnesis do not match. The Prausnitz-Küstren reaction is the introduction of the blood serum of an allergic person to a healthy person. A day later, the doctor determines the level of antibodies in the epidermis, then the same area is treated with an allergen, and the reaction is observed.

Preparation for the procedure

cancellation of glucocorticosteroids and antihistamines 14 days before testing;
compliance with the previously assigned. The result of a test performed on an empty stomach may be incorrect.

The patient must strictly follow the rules determined by the doctor. If the recommendations are violated, false positive and false negative results of skin tests are possible. With a “blurred” picture, you will have to repeat the study again, use microdoses of allergens, which creates some discomfort for the patient. To clarify the diagnosis, additional ones are prescribed, many of which are not cheap.

How is allergy testing done?

Features of the scarification test:

before scratching, the epidermis is wiped with alcohol at a concentration of 70%;
testing in children is carried out in the upper back, in adults - in the forearm area;
on the treated area of \u200b\u200bthe epidermis, the doctor makes small scratches, the distance between them is from 4 to 5 cm. If the procedure is carried out incorrectly (the marks are too close), inaccurate results are often obtained);
with a sterile needle or lancet, the doctor applies extracts or solutions of allergens. For each type of stimulus, the specialist takes a new tool;
for 15 minutes, the patient must hold his hand motionless so that the drops of irritants do not mix, the result is reliable;
according to the reaction on the surface of the epidermis in the scratch zone, the doctor concludes whether this substance is dangerous for a particular person or not. Papules, redness, itching, swelling in a certain area indicate a negative response to this component;
the test result is noticeable after a quarter of an hour. After measurements, analysis of the situation, the doctor removes the remaining drops of the irritant from the scratches. A maximum of twenty allergens can be applied in one procedure.

A prerequisite for correct diagnosis, the absence of complications after the procedure is the high qualification of medical personnel. Doctors and nurses must have diplomas and certificates confirming the right to conduct special studies. Experience is an important point that you should pay attention to when choosing a medical institution: the body of some patients reacts violently to the administration of allergens, anaphylactic reactions develop, and fast and competent medical assistance is required to prevent serious consequences.

Diagnostic results

Skin tests are a highly informative method that allows you to determine the degree of danger of a substance for a particular patient:

a sharply positive test result- pronounced redness, papule size 10 mm or more;
positive reaction- redness is clearly visible, the papule reaches 5 mm;
weakly positive result- severe hyperemia, papule no larger than 3 mm;
doubtful result- there is no papule, but the skin is reddened. To clarify the diagnosis, a blood test is prescribed for comparison with an allergen panel or another type of study at the discretion of the doctor;
negative result- there are no skin reactions on the surface of the epidermis in the area of scratches.

False results: causes

Doctors identify several factors against which inaccurate data are possible:

reception or other medicines inhibiting the development of an allergic reaction;
improper procedure;
reduced skin reaction in a particular patient in a certain period, more often in children and the elderly;
storage of allergen extracts in violation of the instructions, which leads to a change in properties;
setting a test for a substance that is not the main irritant;
too low concentration of the solution prepared by the nurse.

For this reason, personnel must quickly respond to acute symptoms, competently stop signs of life-threatening manifestations. With timely desensitization of the body, negative symptoms decrease after a certain time. The period of disappearance of pronounced swelling, normalization of pressure, elimination of blisters depends on the severity of the case.

Skin tests using extracts and solutions of irritants make it possible to determine in 15-20 minutes whether a particular substance is an allergen or not. The technique is quite safe, the procedure is simple, discomfort is minimal, complications occur in rare cases. An important condition is skin testing by competent personnel in a medical institution.

How are allergen skin tests performed and what do they show? Find out more by watching the following video:

Everyone who suffers from the manifestations of allergic reactions understands how important it is to establish the cause that causes them. the best way detection of an allergen is considered to be an allergy test, which allows you to take into account individual characteristics patient and manifestations of the disease.

Only with early diagnosis is it possible, if not a complete cure for an unpleasant disease, then at least the prevention of its further development.

Carried out to determine the stimulus to which the body responds with an allergic reaction. Knowing the annoying factor, the patient will be able to minimize contacts with him or at least reduce them in a situation where it is not possible to completely avoid interaction.

With prolonged contact with the allergen, a person runs the risk of acquiring chronic forms diseases in the form of asthma or incurable dermatitis. It should also be borne in mind that the daily intake of antihistamines is addictive to them.

Samples are performed if the patient has the following and their manifestations:

hay fever- a reaction to plant pollen, manifested in sneezing, runny nose, nasal congestion and swelling of the mucosa. Usually hay fever is seasonal.
Bronchial asthma: accompanied by attacks of suffocation, coughing, heavy and labored breathing.
food and on certain types of products or drugs: it has various forms of manifestation: skin rash, urticaria, asthmatic manifestations, and even.
accompanied by itching, with an unknown cause of their occurrence.
Conjunctivitis, manifested by lacrimation, itching and redness of the eyes.

Contraindications

There are age restrictions for both adults and children. People over 60 and children under three should not be tested for allergies. There are also contraindications for women.
Do not test pregnant and lactating mothers, you should also not come to the allergen detection procedure in the first days of menstruation.
Testing should not be performed if the patient is taking glucocorticosteroid or other hormonal drugs. It is recommended to do tests 2-3 weeks after stopping these medications.

They never do testing for those people who have had at least once. Testing should not be performed on patients suffering from diseases such as AIDS, diabetes, mental disorders and oncology.

Types of Allergy Tests

Before making tests, the allergist must analyze the previous reactions of the body and determine the group of allergens that will be used in testing.

The procedure is carried out taking into account the age of the patient, his heredity, manifestations of the seasonality of the disease. For the adult population, professional activity is also taken into account.

All samples can be divided into the following categories:

Allergy blood tests

Blood from a vein is taken for analysis to find out which antibodies are present in a person. Usually they take a test for immunoglobulins E and G. This procedure is performed if the rest of the allergy tests cannot be done for any reason. In this case, it is necessary to prepare for the procedure for taking blood.

You should limit yourself to physical activity, follow a diet for at least three days, in which it is forbidden to eat fried, fatty, as well as foods that can cause. A complete cessation of alcohol and smoking is required. The analysis is carried out on an empty stomach.

It is prescribed for the following diseases:

dermatitis and eczema;
bronchial asthma.

Skin tests

Skin tests for allergies consist in the introduction of a certain dose of a substance (allergic irritant), showing the susceptibility of the human body to it.

Testing can be qualitative (the type of allergen is determined) and quantitative (shows the sensitivity of a person to the dose received). No more than 15-20 allergy tests should be done at a time. Small children at the age of 5 are given 2-3 tests.

Scarification test, or prick test, considered to be the most widely used verification method. On the forearm, which is pre-cleaned, the alleged allergens are applied in the minimum dosage, and small incisions are made on the skin at the site of application using a special device - a scarifier. Scarification tests are recommended for severe manifestations of dermatitis, Quincke's edema, bronchial asthma. The accuracy of this method is 85%.
skin test, or applique, is performed most often on the back and is done in the form of fastening strips with a liquid allergen, which is covered with a film and fixed with a plaster. It is carried out with various kinds of dermatitis. Examine the results of the reaction on the skin after 20 minutes, after 5 hours of exposure, and also after a day.
Intradermal tests do in rare situations. The method consists in introducing an allergenic irritant under the skin. Perform such a test when determining an allergy of fungal or bacterial origin.

Provocative tests

The study of allergic reactions by the method of provocative tests is to act directly on the organ that most suffers from negative symptoms.

This allergen detection technique is more accurate than skin tests. But it is carried out extremely rarely, only when it was not possible to identify the irritant by any other means.

nasal test performed using a special inhaler. It contains the alleged irritant. It is administered through the nasal passage by spraying onto the mucosa. If no reaction is observed, then the procedure is repeated with an increase in the concentration of the allergen. The repetition can be carried out up to 10 times. If no reaction is found after this, the sample is considered negative.
Conjunctival test is based on the introduction of physiological fluid into one eye, after which, after 1/3 hour, an allergen with the maximum allowable dosage is dripped into the second eye. If a reaction is detected, the sample is counted as positive. This test cannot be performed with inflammation of the mucous membrane of the eye or with inflammation of the eyelids.
inhalation test rarely carried out. Its use allows you to identify the allergen that affects the appearance of bronchospasm. The patient inhales an aerosol with a minimum dosage of the allergen. The procedure is repeated 5 times within an hour with a frequency of 10-15 minutes. If no reaction is noticed, then testing is repeated with an increased dose of the allergen.

The specifics of the tests

Any allergen testing must be done under the following conditions:

Performed strictly on an empty stomach.
Be sure to conduct tests in a medical institution and only medical specialists.
In the room where samples are taken, they should be available to help with an unpredictable reaction. The application of samples should be carried out in the presence of a physician. Even at the minimum dose of the injected allergen, a response of the body in the form of Quincke's edema can occur.
It is possible to conduct a test only when at least 2-3 weeks have passed since the last exacerbation. Also, the patient should not suffer from colds and infectious diseases.
The day before testing, you should stop taking any antihistamines in order to obtain a reliable result.

Features of conducting tests in children

Before testing, parents should prepare the child for this procedure. Must be submitted before testing clinical analysis blood and urine.

Testing for allergens in children has its own characteristics. IN childhood frequently vaccinated against various diseases. Allergy testing can only be done 3 months after the next vaccination.

The doctor can also prescribe allergy tests for children as a preventive measure. if the next of kin suffer from a severe form of an allergic reaction. This should be done in order to establish the possibility of an allergic reaction of the body at the initial stage to prevent its development. For example, if a mother has pollinosis, then the probability that the child will suffer from the same disease increases to 75%.

The allergist must determine what form of allergy the child has. This will determine the choice of method for conducting tests, as well as at what age this procedure can be done. Children with a passive form are recommended to be tested no earlier than 5 years, since at this stage the body can cope with allergies on its own. For special indications, tests at the age of 3-4 years can be prescribed.

Usually in children, an allergen is detected in the form of skin tests.

Sample evaluation

After testing, it is important to correctly evaluate the results obtained. The doctor evaluates the samples according to the reaction rate. If the skin at the injection site of the allergen turns red, blistered, swollen during the first hour of the examination, then the reaction is considered instantaneous, and the test is positive. If the reaction to the injected allergen occurs after a day, then the test result is considered weakly positive.

Also, the reaction is evaluated by measuring the amount of reddening of the skin:

no changes are observed - a negative test;
up to 3 mm - doubtful reaction;
over 3 mm - a positive reaction.

Most often, allergies are associated with a violation of the immune system. Therefore, if any type of allergic reaction is detected, measures should be taken to strengthen immunity.

There are various methods for conducting allergy tests. Which method of establishing the allergen should be chosen should be determined by the allergist. The choice of method is influenced by factors such as age, heredity, type of allergic reaction, seasonality of its manifestation. Once the irritant is identified, the patient will be able to avoid contact with it, which will help maintain their health.

An allergic reaction can occur to food, animal skin particles, dust, mold, pollen from various plants, and much more.

To establish what exactly provokes a pathological immune response, the doctor prescribes examinations.

These include: a clinical standard blood and urine test, a biochemical blood test for the determination of class E immunoglobulins, skin tests for allergens.

Indications for allergy tests

Only a doctor can refer to analyzes and choose a method based on the overall picture of the reaction. Skin-allergic tests are considered the most common and fastest.

Important points to be aware of before starting trials:

Did this reaction occur for the first time or have there been cases?
Patient's lifestyle.
Used products.
Has there been contact with any animals?
Does anyone in your family have similar symptoms?
What kind of bedding does the person use?
When and how did the first allergy symptoms appear?
What medications is the patient taking or taking in the near future?
Chronic disease in a patient.
Are there sharp infectious diseases for the current day?
Whether the patient has ever had anaphylactic shock is a very important point. If the patient answers in the affirmative, then skin-allergic tests cannot be performed.

Then the doctor conducts a visual examination of the patient.

Indications for the appointment of allergy tests are:

formations on the skin - rash, redness, vesicles, roughness, itching;
unreasonable rise in temperature;
prolonged bouts of coughing that do not respond to treatment;
sudden runny nose and nasal congestion;
causeless lacrimation, itching, redness of the eyes;
relatives suffering from allergies;
the patient noticed a direct dependence of manifestations on food products, medicines, after contact with animals, at a stormy moment of flowering;
a blood test showed an increase in eosinophils and basophils.

The appearance of any allergic manifestations is the reason for skin tests.

Video from Dr. Malysheva:

Types of allergy tests

All examinations are carried out exclusively in medical institutions, as medical personnel have a specialized focus and work experience. In the event of sudden unforeseen reactions, they will be able to provide first aid, which can save the life of the victim.

The following methods are used to conduct allergy tests:

Application tests are special strips on which certain allergens are applied, or gauze cloth soaked in an allergen concentrate. The application is applied to the body and fixed.
Scarification test - a certain allergen concentrate is applied to the skin of a person and a scratch is made at the site of application with a scarifier.
- this is the application of a concentrate to the skin, after which a 1 mm puncture is made at the site of application with a special tool.
Provocative methods are when the allergen is applied to the mucous membrane of the eye or nasal mucosa, or inhalations are used to introduce the causative agent of the reaction.

Results of an allergological study

If a scarifier or prick test is performed, the result is evaluated 20 minutes after the application of the allergen.

If the application test is chosen as the method, then the result is evaluated after two days.

The brighter the skin reaction, the more likely it is that a particular allergen caused the aggression of the immune system.

If there is no inflammation at the site of skin contact with the allergen, then the reaction is negative.

If the inflammation is up to two millimeters in size, then the reaction is called doubtful. If the inflamed area has a size of more than three millimeters, then such a reaction is considered exactly positive.

Based on the results of the diagnosis, it is possible to accurately determine which substances cause allergies, after which the doctor will select the correct treatment.

How are allergy tests done in adults?

It is better to do skin tests for allergies in autumn or winter days. During this period, the general allergic background is much lower, which will make it possible to obtain more accurate information as a result of the analysis.

To obtain reliable results, it is necessary to properly prepare for the study:

conduct skin tests only in a state of stable remission;
skin tests are best done on an empty stomach, the last meal should be at least 8 hours ago;
the day before, exclude all suspected allergens;
the study should be carried out in the morning;
do not drink alcohol in anticipation of the test and do not smoke on the day of the test;
limit the intake of medications, especially antihistamines and hormonal ones, a few days before the test.

There are contraindications when the test should be abandoned or postponed until better times:

pregnancy and lactation;
age 60+;
infectious diseases;
violation of the integrity of the skin;
previously had anaphylactic shock;
acute period of allergy.

All instruments used during the procedure must be disposable and sterile.

The protective sheath must be removed in the presence of the patient.

The laboratory worker must put on new sterile gloves before each patient and clean their hands with special disinfectant solutions. Before applying concentrated allergens, the application site is treated with alcohol.

No more than fifteen types of allergens can be applied to a person at a time.

If the application method is used, then the person must wear the attached dressing for two days without removing it. It is necessary to abandon water procedures for these two days so as not to distort the results.

Compliance with the rules of hygiene and the rules for preparing for analysis will protect your health and help you get reliable results.

Allergic tests in children

Skin tests in children look the same as in adults. The exception is age. Children under three years of age are not shown this diagnosis. The risks are too great and the result may be false.

Indirect skin tests

If direct skin tests do not give any result, then doctors move on to indirect tests. A healthy person is injected with the serum of the patient's blood plasma under the skin. A day later, an analysis is taken for the presence of antibodies and an allergen concentrate is applied at the injection site of the serum. And again, blood is taken for analysis.

This procedure is almost never used in our time, as there are great health risks:

infection with latent infections from a donor is possible;
a severe reaction to an allergen is possible.

That's why modern world increasingly abandons the indirect method for allergens.

Skin tests

Children's allergists often give children skin tests for allergens.

But there are a number of contraindications:

age up to 3 years;
acute period of allergy;
acute infectious and inflammatory disease;
long-term use of hormonal drugs;
previously had an anaphylactic condition.

In preparation for the analysis, possible allergens must be removed from the child's daily life. Children can be tested three hours after eating.

It is important to use exclusively sterile and disposable instruments during the sample. In a medical institution where diagnostics is carried out, there must certainly be an anti-shock first aid kit in order to provide timely emergency assistance when there is a violent reaction to allergens.

The results of the study can be assessed 20 minutes after the pathogen is applied to the skin.

panels for allergens

For more accurate and safer diagnosis, pediatric panels for allergens are used.

With their help, you can identify the following allergens:

food;
vegetable;
animals;
for milk protein;
on dust mites.

This procedure is considered completely safe for the child, since there is no moment of contact of the child directly with the allergen. This study can be performed on children almost from birth, but more exact result can be obtained from the age of six months.

Results after diagnosis can be obtained within a week after blood sampling. The response of the laboratory should be evaluated by a physician. According to reports, he will prescribe the required treatment.

Allergy symptoms need to be stopped at the most early stages to prevent further deterioration of health. A qualified doctor will help determine the exact cause of the violent reaction of the body. He will prescribe the required studies, conduct a thorough examination and question the patient, which will help him make an accurate diagnosis and prescribe the correct treatment.