If children have a positive reaction to the test. How to decipher the results of Diaskintest, what is the norm? How is the result of diaskintest assessed?

Diaskintest - modern drug to identify latent forms of tuberculosis. Compared to the one known and used for almost 100 years, the new primary diagnostic tool makes it possible to almost accurately determine whether a person is infected with tuberculosis bacteria or not.

Let us remember that these bacteria are also called. They are transmitted from a sick person through the air, through contact, through shared dishes and other household items. The Diaskintest test allows you to detect the presence of bacteria in the body at a stage when the disease does not manifest itself.

Classmates

What kind of test is this?

Sometimes people wonder what kind of vaccine Diaskintest is. But this is not a vaccination, but a test sample. The Diaskin test shows the body's response to tuberculosis in inactive or active forms. A positive result on this test is an absolute indication for starting chemotherapy to prevent the disease from becoming active.

The Diaskin test is an immunological test in which protein allergens (antigens) are introduced into the skin to detect the body's immune (interferon) response. If the answer is yes, then, therefore, immune system person is familiar with these protein allergens. This indicates that the person is either infected or is in an active stage of the disease.

How is it done?

The test for tuberculosis is carried out in the traditional way like all other tests.

Diaskintest is done on any hand in the forearm area (the space between the wrist and elbow). If a person is right-handed, they try to place the test on left hand(and vice versa, from a left-handed person to a right-handed one), as less active, in order to minimize possible external mechanical irritation. But there are cases when the Mantoux and Diaskin tests are performed simultaneously on different hands. In general, the main thing is that the person does not scratch the injection site and does not accidentally provoke an irritating reaction.

The test for tuberculosis is administered intradermally with a special tuberculin syringe with a thin needle.

Why do they do it?

Since many are still confident that the Diaskin test is a vaccination, and today there is an increasing irrational negative attitude towards vaccinations, for example, parents often wonder whether or not to do the Diaskin test for their children. The following judgments can be made here.

In fact, up to 95% of adults are infected (carriers) with Koch's bacillus. Today, such carriage is commonly called the latent form of tuberculosis. This is not a disease, but under certain conditions it can develop. And this happens in less than 1% of people. At the same time, the infectious process for a long time proceeds secretly and asymptomatically. It is not possible to identify it by external signs without performing allergen tests. Early detection of the tuberculosis process significantly increases the chances of recovery.

How often can I do it?

Diaskintest is done as often as required by the recommendations of the Ministry of Health: the test is mandatory for all children from 8 to 17 years old once a year.

When deciding how often a diaskintest can be done for a child or an adult, they are guided by the following standards:

• After a negative test, the next one can be done after 2 months;
• after any vaccination – in a month;
• after suffering acute infectious diseases - in a month.

For those who are registered with a phthisiatrician at an anti-tuberculosis dispensary, a control test is performed once every 3-6 months.

Diaskintest can be done from the age of 1 year upon receiving a positive Mantoux test.

Preparation

No preparation is required for the Diaskintest analysis. A necessary condition is the absence of any infectious diseases during the month before and at the time of the test.

Composition of the drug

The drug Diaskintest contains:

• Specially prepared proteins of tuberculosis bacteria CFP10 ESAT6;
• preservative – phenol;
• stabilizer – polysorbate;
• sodium and potassium phosphates;
• sodium chloride;
• water.

Country of origin and manufacturer: Russia.

Where can I do it?

The Diaskin test is carried out in:

• Schools;
• kindergartens;
• children's clinics;
• anti-tuberculosis dispensaries;
• anti-tuberculosis centers and institutes.

The emphasis on children's institutions is explained by the fact that modern health care standards require Diaskintest to be performed on a child. Since children and adolescents are most susceptible to infection with tuberculosis bacteria.

Adults, including women during pregnancy, are examined if they have contact with infected people, or if they are registered with the PTD.

Correct assessment of results

Diaskintest is checked 2-3 days after placement.

How to evaluate the result:

• negative (normal);
• doubtful (false positive);
• positive.

Normal in children and adults

The norm according to Diaskintest is complete absence of reaction: no redness, no swelling (papules).

Reaction by day

The reaction to Diaskintest by day is not significant. Redness may occur on both the first and second days. This is not a very good sign, but a false positive reaction is quite likely.

The first reaction may appear 6 hours after the injection.

The result of diaskintest is the body’s immune response. The intensity of this response is influenced by the overall immune status. For a person who is not in an immunosuppressed state, the response to an introduced allergen in the presence of a latent form of tuberculosis will be dynamic. Redness and the appearance of an inflammatory reaction in the form of a papule are possible already on the first day after the Diaskin test. Over the course of 72 hours, the reaction will increase, showing maximum results in both children and adults on the third day. Further, the reaction will begin to fade, after which it will not be possible to make a correct assessment.

Negative result

Of the visible signs, the following are considered normal (i.e. the Diaskin test is negative):

• Injection mark;
• possible 1-2 mm bruise at the injection site;
• a colorless compaction with a diameter of no more than 1 cm at the site of the sample (“button”, “lemon peel”).

Thus, the Diaskin test should not show redness or papule.

False positive

The test may be false positive or questionable. This is how the presence of redness without the formation of a papule is classified.

In case of a false-positive Diaskintest, a person should be referred for further consultation to an anti-tuberculosis dispensary, where he undergoes additional tests, fluorography, and also undergoes a repeat Diaskin test after 2 months.

Positive

If a person has a positive diaskintest result - that is, an inflammatory papule of any size is present - this means that such a person is infected with the tuberculosis bacillus.

In an adult

With a positive diaskintest in an adult, the size of the papule does not matter; the fact of its presence is important. For classification purposes, the conventional sizes of swelling at the injection site were established:

• Up to 5 mm. – weak;
• up to 9 mm. – moderate;
• more than 10 mm. – expressed.

The more pathogens there are in the body, the larger the size. inflammatory process at the injection site.

What to do if the diaskintest is positive: treatment and registration at a dispensary is necessary.

In a child

A logical question for any parent: what to do next if the diaskintest shows a positive result. Additional tests will be required to determine whether the disease is latent or active. But in any case, at least 3 months of treatment will be prescribed, for example, Isoniazid.

Complications and side effects

Diaskintest does not cause any harm or complications. The bacterial fragments it contains are not harmful to either a child or an adult.

Very rarely side effect Diaskintesta can manifest itself in the form of symptoms of general intoxication:

• Increase in temperature;
• malaise;
• headache;

This is a normal immune reaction to the administration of a protein drug.

Hyperergic reaction

A hyperergic reaction to Diaskintest is a positive result with the formation of a large papule more than 15 mm, irritation and inflammation of the tissue around it.

Bruise at the injection site

A slight bruise after diaskintest is not dangerous and is considered a normal side effect of the procedure.

Contraindications

Diaskintest has contraindications:

• Any acute diseases or in the acute phase;
• skin diseases;
• epilepsy;
• allergic conditions;
• vaccination (including) within 1 month. before testing.

Can this be done if you have a cold?

Colds, coughs and runny noses are classified as acute infectious diseases. Diaskintest cannot be performed with these symptoms.

Allergy to Diaskintest

The drug contains a foreign protein. Therefore, it itself is an allergen. Diaskintest can cause allergies and allergic reactions. Allergic conditions are a contraindication for testing.

Contraindications for children

In addition to the above, there are no other contraindications, including for children.

What can and cannot be done?

What not to do after vaccination with Diaskintest:

• Apply detergents, cosmetics and perfumes to the sample site;
• apply any medications to the injection site;
• rub and scratch the injection site;
• cover the sample with a plaster or wrap it with a bandage.

Otherwise, you may get redness on the first day and have an incorrect assessment of the results.

Is it possible to wet your hand?

It is not prohibited to wet your hand after the diaskintest.

Can I shower after the test?

Can. But you should avoid getting caught detergents to the sample site.

Is it possible to eat sweets?

There are no restrictions that the Diaskin test imposes in this regard.

What should you not eat during diaskintest?

There are no dietary restrictions. You can eat the foods you normally eat.

Useful video

The video describes a new method for diagnosing tuberculosis - diaskintest:

Conclusion

Diaskintest can make mistakes, like any medical test technique. The sensitivity of this method is about 80%. Accuracy – almost 100%. The Diaskintest tuberculin test is an order of magnitude more accurate than. Mainly due to the fact that it does not show a positive reaction in individuals with acquired anti-tuberculosis immunity.

Therefore, Diaskintest tuberculin diagnostics is the most reliable and safe way to find out not only whether a person has tuberculosis, but also to tell whether he will get sick in 1 or 2 years.

Tuberculosis is a contagious disease caused by Koch's bacillus. All adults and children over 1 year of age should undergo annual screening for infection. Examination methods can detect the disease at an early stage. Diaskintest is a reliable way to detect tuberculosis. A positive result is the basis for a fluorographic image of the lungs.

To detect tuberculosis, everyone, regardless of social status, is prescribed an annual examination. The diagnostic method is determined by the age of the patient. Timely treatment in 70% of cases allows you to completely get rid of the pathogen. Without treatment, the risk of death doubles.

The main ways to determine the presence of Koch's bacillus in the body:

Characteristics of the study

Diaskintest is a method for determining tuberculosis. It is similar in diagnostic rules to the Mantoux reaction. The active substance is mycobacterial proteins that do not infect humans. The reliability of Diaskintest is higher than that of the Mantoux test, but it is used less frequently.

Mantoux gives a positive answer if the patient is prone to allergies, and Diaskintest reduces the likelihood of such situations.

Photos of a positive result of the diaskintest and the Mantoux test can be seen in the phthisiatrician’s office. They will not have any significant visual differences, but a positive result of the diaskintest indicates that the person is infected with mycobacteria.

Diaskintest can more accurately show a positive or negative result. The photo proves that Mantoux is not that effective.

After identifying the disease and undergoing therapy, the result becomes negative. But Diaskintest does not cause a reaction in people who have previously received a BCG vaccination. Therefore, it is not used to select people who need booster vaccination.

What does the solution consist of?

Diaskintest is injected subcutaneously into the forearm. The body reacts to mycobacterial proteins. The method allows you to determine whether a person is infected with tuberculosis. But this method cannot distinguish whether the patient is a carrier of bacteria or is developing a disease. If the test is positive and there are no symptoms, additional examination methods are prescribed.

Diaskintest includes:

• saline;
• artificial proteins of tuberculosis bacteria CFP10 and ESAT6;
• potassium and sodium salts;
• preservative phenol, in an amount of 0.25 mg, which is a safe dose;
• stabilizer polysorbate 80.

Features of the test

The procedure for performing the Diaskintest and the Mantoux reaction is the same. Before diagnosis, it is necessary to make sure that the patient is healthy and does not have allergic reactions. Despite the fact that the test is 90% reliable, the additional burden on the immune system causes a false positive reaction.

Rules for conducting diaskintest:

• an injection syringe is required with a thin needle;
• take the dose of the drug;
• the substance is injected subcutaneously into the inner part of the forearm;
• You can bet in any hand, preference is given to the left;
• if the drug is administered after a positive result for tuberculin, then use the other hand;
• on the 3rd day, the nurse evaluates the result, which determines whether a person is infected with tuberculosis or not.

Is it allowed to wet the sample?

After the injection, you must follow some rules to avoid getting an incorrect result. The site where the test for tuberculosis was taken should not be scratched, because there is a high probability of infecting the wound and not getting the correct result.

This may cause a false positive result. You must adhere to this rule until the doctor examines the injection site.

For everyone else, you can wet your forearm after the test, but do not rub it with a washcloth, scrub or other means that can damage the skin. This diagnostic method does not provide for other restrictions on diet and lifestyle.

Diagnostic frequency

The frequency of injections depends on the age and health of the patient:

Determining the presence of pathology by test

The result after the injection is determined after 3 days. When examining the injection site, the doctor determines the size of the red spot and papules.

Depending on the value of these indicators, the degree of assessment is revealed:

Reaction	Papule	Redness
negative	absent	2 mm or less
dubious	up to 4 mm	present
positive	6 mm or more	present
hyperergic	more than 14 mm	the appearance of compactions, blisters, skin breakdown

A positive result of the diaskintest (photo below) is confirmed by a doctor’s report. A papule from 5 to 14 mm indicates that a person is infected with mycobacteria.

A negative result indicates that the person is healthy. All other injection results require additional diagnostics. With a negative test, there is no swelling, but the injection site remains. A small hematoma occurs due to poor-quality research, which can affect the determination of the result.

If the doctor determines a questionable reaction, the patient will be sent for a repeat test after 2 months. If the result is negative, the child or adult can attend the group. It is prohibited to vaccinate against tuberculosis within a month. Additional research methods are not used for 12 months.

Positive response

Diaskintest gives a positive result in the following cases:

• there is an active inflammatory process in the body, tuberculosis is progressing;
• a person is infected with mycobacteria, but the disease has not yet occurred;
• performing an injection if there are contraindications, in which case the result will be false positive.

An X-ray photograph provides a more accurate identification of the stage of the disease. It shows an inflammatory process in the lungs. If the disease has not yet occurred, then the phthisiatrician will see the Gong lesion in the photographs. The immune system copes with mycobacteria and tuberculosis does not develop. Therefore, the disease progresses with a decrease in the body’s defenses and adequate nutrition.

False positive test result

A false positive reaction occurs if the injection was carried out in the presence of the following contraindications:

• Damage to the skin at the injection site and infection of the wound.
• The presence of allergic reactions, increased atopic dermatitis.
• Autoimmune diseases.
• Availability viral infection. At the same time, the manifestation of ARVI may not yet have occurred.

People prone to allergic reactions must take antihistamines before receiving the vaccine. Avoid drinking alcohol as it may cause redness at the injection site.

Actions to take if an infection is detected

A positive result of the diaskintest (photo below) is a reason to refer the patient for a consultation with a phthisiatrician. The doctor will give a referral for general analysis blood. If the infection spreads in the blood, there will be a decrease in leukocytes and an increase in ESR. Tuberculosis develops asymptomatically up to 2 years.

During this period, the patient is not contagious, but when immunity declines, the disease becomes open. Therefore, the doctor must promptly determine the stage of development of the disease and prescribe treatment to prevent infection of other people.

Adults need to undergo fluorography to identify lesions in the lungs. For children, X-ray examination is recommended due to the lower radiation dose. If there are no clearly defined foci of inflammation in the images, an MRI of the lungs is required.

Therapy for lung disease

Treatment of tuberculosis lasts 6-8 months. During this time, depending on the stage of the disease, you must follow the doctor's recommendations. In severe cases, bed rest is required. If you are in average health, you should avoid physical activity and stress. As your condition improves, you can switch to normal mode.

The time it takes for recovery to occur depends on the patient’s immunity, the resistance of the mycobacterium to the prescribed drugs, and concomitant diseases.

First line anti-tuberculosis drugs include:

At this stage, combining drugs can stop the development of the disease. The duration of treatment, frequency of administration and dose of medication is determined by a phthisiatrician based on the form of tuberculosis, previously prescribed treatment and general condition patient.

In severe cases use surgical methods. They are necessary for complex forms of the disease and the development of complications. Surgery is resorted to in 25% of all cases of the disease. Lung bleeding is a life-threatening condition and requires immediate intervention.

Depending on the development of the disease, the surgeon removes part of the organ, a lobe, or the entire lung. Possibly, cutting off the destroyed area - cavities.

If left untreated, the mortality rate from tuberculosis reaches 50%. The risk increases in older people, HIV-infected people, patients diabetes mellitus. During treatment, you should not take a break from taking medications.

It is not recommended to independently determine the positive or negative result of the diaskintest from photographs on the Internet. Additionally, during therapy, increased nutrition and vitamin intake are required. In the active stage of the disease, treatment occurs in an anti-tuberculosis dispensary.

Article format: Lozinsky Oleg

Video about diaskintest

What is Diaskintest and how is it carried out:

To determine latent forms of tuberculosis infection, a modern remedy, Diaskintest, was invented. Compared to the outdated Mantoux test, the new drug accurately and without errors determines whether a person has become infected with Mycobacterium tuberculosis or not.

Koch's bacillus, named after its discoverer, is transmitted from another sick person through household contact: through conversation, coughing, shared utensils, household items, or direct contact. The reaction to Diaskintest reveals the presence of tuberculosis bacillus on early stages when the disease does not manifest itself clinically.

Diaskintest: description

Some people ask what kind of research this is. The Diaskintest test is not a vaccination. The test checks the human body's response to tuberculosis infection, as well as test test shows what form the disease has - active or inactive.

A positive Diaskintest indicates that there are indications for therapeutic therapy to prevent the transition of tuberculosis disease to a critical phase.

The test is an immunological test, in which protein fragments are administered intradermally to the patient in order to obtain an immune response from the body. If a positive result is detected after injection of the Diaskintest drug, it means that the person’s defense system has encountered these allergens. Doctors then assume that the patient has recently become infected or the disease is in an active stage. When Diaskintest is negative, then there is nothing to worry about.

How is the test carried out?

This TB test is performed in the same way as other traditional test samples. The drug is administered with a special thin syringe with a small needle into the inner middle part of the forearm.

It doesn’t really matter which hand the injection is given in, but if the person is left-handed, they try to give the injection in the right hand, and when the patient works better right hand, the injection is carried out in the left limb. This is done in order to minimize possible mechanical damage to the sample site.

In some situations, Mantoux and Diaskintest tests are performed on different limbs. Then the main thing is that the patient does not provoke mechanical irritation and does not scratch the injection site to avoid local inflammation.

Why is a sample needed?

Many people are still convinced that a test for tuberculosis is a vaccination. The population's negative attitude towards them is growing every year. Parents are in doubt whether to give their child Diaskintest or not. The following can be advised to such mothers and fathers.

In fact, in adults, Koch's bacillus is often found in the blood. More than 90% of people are hidden carriers. Such bacterial carriage is a latent tuberculosis course. This is not a disease, it appears only under favorable conditions, it occurs in 1-1.5% of the population.

For a long time infectious inflammation proceeds without any symptoms in an indeterminate form. Identify it by clinical signs without diagnostic tests it is impossible. The test results of the sample help to determine the tuberculosis process in the early stages, which significantly increases the patients’ chances of cure.

Dough composition

The drug was developed and produced in the Russian Federation.

• Prepared protein tuberculosis allergens;
• Phenol for preservation;
• Polysorbitol as a stabilizer;
• Sodium phosphate, potassium;
• Sodium chloride;
• Distilled water.

There is no need to prepare in any special way for the test. The required conditions are the exclusion of any infectious diseases a month before testing and at the time of the injection.

Who can and who can't get tested?

• During a preventive examination for tuberculosis, if a person is not sick, a negative Diaskintest is determined;
• To monitor disease activity in patients receiving treatment. With complete cure, a negative result is revealed;
• To distinguish it from other ailments not related to tuberculosis;
• To check the quality of the BCG performed, since Mantoux in this case is positive;
• To monitor the quality of treatment.

• Acute infectious processes, colds;
• Relapse of chronic illnesses;
• Allergies in the body, acute period of asthma in the lungs;
• Skin diseases with pustular rashes;
• Epileptic seizures;
• Vaccination with vaccinations.

Sometimes the test causes side effects, such as weakness, headache, and a slight increase in body temperature. These conditions are not dangerous, they pass very quickly.

Sample decoding

Diaskintest results are assessed after a few days, usually after three days. In this case, there is no need to take measurements by day. In order to evaluate the results in an adult, the injection site is carefully examined, the size of the papule is determined, and the redness of the skin is taken into account.. Many people are interested in what it looks like negative test and what is considered normal.

• Diaskintest is normal - when the result is negative, an infiltrate does not form on the skin, there is no redness or its size does not exceed 2 centimeters. If the test was not done very successfully, a hematoma at the injection site is possible;
• A questionable result is slight hyperemia, but there is no dense infiltrate, or the papule should not be more than 4 millimeters in diameter;
• A positive result on Diaskintest – a papule larger than 5 millimeters appears;
• The pronounced result is that the diameter of the infiltrate is more than 1.4 centimeters, severe redness and ulcers around the injection site will appear, and regional lymph nodes will enlarge.

Diaskintest test results should be checked by a doctor or specially trained nurse. On the first day there is almost no reaction. A hematoma at the test injection site interferes with the correct interpretation of the result; because of it, redness is not always visible. In some cases there is false positive test, then the patient is sent for further examination, since repeated injection of the test is allowed only after 60 days.

If Diaskintest gives a positive reaction, a papule larger than 0.5 centimeters has appeared, this tells the doctor that an inflammatory process is actively developing in the body. This condition occurs during primary infection or during the acute phase of the disease. Infection does not always cause the development of tuberculous inflammation. With good immunity, the body's defenses easily cope with tuberculosis bacteria.

In this case, together with the introduction of mycobacteria, calcification is formed, and specific immunity is developed. Calcification is detected on a fluorogram or during radiography.

Next, such a patient should be referred for consultation to a specialist in order to perform additional examinations and clarify or refute the diagnosis. Consultation with a phthisiatrician is also required in case of a severe reaction or a questionable test. Such people should also be further examined.

Reasons for questionable or pronounced reactions

What should a person do if there is a positive, comparative or pronounced test? Even in the case where there is no tuberculosis, the presence of such a reaction indicates that there are problems in the body.

• The test was done despite contraindications; sometimes the patient does not know about the presence of infection in the body or it is asymptomatic;
• Secondary infection occurred at the injection site, which is common in children;
• Allergic predisposition of the patient, in such conditions the body’s reaction to allergens can be unpredictable;
• Autoimmune diseases, chronic somatic diseases.

How long it takes for the redness to go away and the lesion to stop itching depends on the individual characteristics of the body. There is no exact data that water affects the test result, but it is better to remain careful and not get the injection site wet.

If a person has a positive reaction to an injection of the drug, they need to be fully examined for tuberculosis. Such a patient undergoes an x-ray examination and is prescribed laboratory tests, the Mantoux test is also done.

When a positive test is detected in a child, the structure of the lungs is carefully examined on an x-ray. There are other tests for tuberculosis that are not dangerous. For children, an additional examination is prescribed by a TB doctor.

Although a medical examination is voluntary, you cannot refuse to carry out a Mantoux or Diaskintest test in order to exclude possible complications and consequences.

Video

Video - all about Diaskintest

The number of tuberculosis cases among the population is growing from year to year. You can become infected through airborne droplets through contact with a sick person - coughing, sneezing, or even just saying something. But not every infection ends in illness; according to statistics, about 30% of people are carriers of the tuberculosis bacillus, which can remain latent for many years.

In our country, two methods of screening the population for tuberculosis are mainly used - fluorography and the Mantoux test.

Fluorography is performed annually on the entire adult population, as well as teenagers from 15 years old. When performing fluorography, the body receives radiation exposure, so children under seven years of age are not given it, but rather a Mantoux test is performed, in which tuberculin is injected into the body.

Tuberculin is obtained from Mycobacterium tuberculosis and is toxic. Everyone must have gone through this in childhood and remember that a red papule forms, which cannot be combed or wetted with water.

The Mantoux test does not always provide an accurate diagnosis; it often shows a false positive result. Patients then need to undergo an X-ray or computer examination of the lungs in order to refute or confirm tuberculosis.

Sometimes after testing for the Mantoux reaction active tuberculosis developed, such cases are known, but they are few. New drug Diaskintest for tuberculosis contains only antigens of active mycobacteria, which help the formation of antibodies in the human body, and not the active mycobacteria themselves.

The Diaksintest method appeared and became widespread due to the fact that the Mantoux reaction test is sensitive to two subspecies of mycobacteria - bovine and human. In rural areas, in pastoral areas, the “bovine” strain of tuberculosis is common. You can become infected through fresh milk, which often drunk unboiled. Therefore for more precise definition It was the human subspecies of mycobacteria that the Diaxintest test for tuberculosis appeared.

The sensitivity of Diaksintest is 90%, while the sensitivity of the Mantoux test is no more than 50%. The Diaskintest test makes it possible to determine whether a person is infected with tuberculosis or not while the disease is in a latent form.

What does Diaksintest consist of?

The dose of phenol is 0.25 mg, and is safe for both adults and children.

The drug was developed in Russia, is produced here.

Indications for Diaskintest

The drug Diaskintest is used to detect tuberculosis in the following cases:

• preventive examination;
• assessment of the dynamics of the process in patients undergoing treatment for tuberculosis: the reaction to the test decreases to negative in case of cure;
• to exclude tuberculosis in case of illness with other diseases;
• to exclude tuberculosis after BCG vaccination. The fact is that the Mantoux reaction after this vaccination is not informative and usually shows a positive result;

Diaksintest and the Mantoux reaction test are not interchangeable.

Phthisiatricians use Diaksintest after a positive Mantoux reaction to clarify the result.

Disadvantages of the Diaskintest test

That's why less sensitive Mantoux test is still actively used in anti-tuberculosis diagnostics. There are cases when a patient is simultaneously given a Mantoux test on one arm and Diaxintest on the other.

How is Diaskintest done?

Diaskintest is done similarly to all tests: on any hand with inside in the forearm area, where the skin is thin, the drug is injected subcutaneously with a special tuberculin syringe with a thin needle.

The Diaskintest test is always performed on an outpatient basis. The staff must also be specially trained.

In which institutions can Diaskintest be done?

• in children's institutions;
• in anti-tuberculosis dispensaries;
• in anti-tuberculosis centers.

Particular attention to children's institutions is due to the fact that children and adolescents are primarily at risk.

Adults are examined if they come into contact with infected people, for example, one of the family members is sick with tuberculosis and contact cannot be avoided. Or if they consist registered at the anti-tuberculosis dispensary. Patients with diabetes must undergo Diaskintest. Children who come into contact with infected people undergo the entire diagnostic complex: Mantoux test, Diaskintest, chest x-ray.

The Diaskintest result is checked after 72 hours.

As a rule, a transparent ruler is used. The size of the redness is measured or papules diagonally.

In turn, the sizes of the papule are divided into the following categories: weak reaction (up to 5 mm), moderate reaction (up to 9 mm), severe reaction (whiter than 10 mm). The division is quite arbitrary, but this information is used later when the patient undergoes treatment, and the results of previous tests are compared with subsequent results.

A papule measuring 15 mm or more may form. Inflammation of the skin around it may also form. Then they talk about a hyperergic reaction to Diaskintest.

All patients with a positive, questionable test result and a hyperergic reaction to Diaskintest are sent for further examination with consultation with a specialist. Standard examination includes: Mantoux test, x-ray, urine and blood tests. This rule applies to both children and adults.

There is one interesting fact. On fluorography or x-ray, formations are often visible - calcifications or Gohn's lesions. This means that the patient was infected, but his immunity allowed the body to independently cope with mycobacterium tuberculosis. The disease as such did not occur, and immunity developed. In these cases, the Mantoux reaction is either positive or doubtful.

Side effects

Adverse reactions on Diaskintest are extremely rare. They can manifest themselves in the form of headache, fever, general malaise, i.e. normal immune response during testing and vaccination.

A small bruise may form; this is also not dangerous.

Contraindications

Diaskintest, as an allergen, can cause an allergic reaction because it contains a foreign protein.

Children who have had Diaskintest vaccinations can set as standard, in a month. This also applies to BCG.

What regimen to follow after the Diaskintest test

• It is forbidden to wash with soap or shower gels, although the sample site can be wetted;
• It is forbidden to comb the injection site;
• Do not use a patch or bandage.

You can eat and drink everything, with the exception of alcohol consumption in adult patients. Reactions involving alcohol metabolism products in the body can cause redness in the injection area, and an accurate assessment of the result will also be impossible.

Now that it has become more clear what Diaskintest is, let’s turn to the opinion of doctors.

According to reviews of many phthisiatricians, Diaskintest allows in most cases to almost accurately determine the presence of Mycobacterium tuberculosis in the body and begin treatment. While fluorography shows an existing disease, the Mantoux test has a very large degree of error and is not informative if the patient has acquired anti-tuberculosis immunity.

Scientific progress does not stand still. Every year, new drugs and more advanced diagnostic tests appear around the world. Thus, in the last 5-10 years, two completely new tests for tuberculosis have begun to be used in medical practice: Diaskintest and Quantiferon test.

What determines the reliability of the results?

Diaskintest is a modern diagnostic test for the presence of Mycobacterium tuberculosis in the human body. Other staged tests used to date (the most common: the Mantoux test) are not always accurate.

However, the reliability of Diaskintest results is also a variable value and can be reduced as a result of many factors: ignoring contraindications, violation of administration technique, etc.

Diaskin is the introduction into the body for diagnostic purposes of a completely synthetic drug, which consists of two main antigens: CFP 10 and ESAT 6. They influence the human body’s production of specific antibodies to pathogenic strains that cause tuberculosis.

This drug is absolutely safe to use. It does not contain live pathogens that affect the occurrence of the disease. In addition to specially prepared bacterial proteins, the drug contains the following components:

• phenol;
• polysorbate;
• phosphate compounds of sodium and potassium;
• sodium chloride;
• water.

The commonly used staged Mantoux test shows reliable result ranging from 50% to 70%. It can give a positive result both for the presence of a true infection of the body, and for a post-vaccination reaction - BCG vaccination.

Diaskintest results are more reliable. The accuracy rate is equal to 90%. However, it should be noted that this modern test is used only as a test for the presence of Mycobacterium tuberculosis in the body: carriage or infection, even in the asymptomatic stage.

The Diaskintest result is not used for BCG revaccination. According to the vaccination schedule, a staged Mantoux test is required before vaccination with BCG.

Indications for use

The modern test is approved for use starting from one year. The most common prescribing indicators include the following:

The following categories of the population should be subject to mandatory diagnostics:

• persons released from prison;
• internal organ workers;
• military;
• persons with a questionable Mantoux test result.

Contraindications for use

Diaskintest must be carried out before routine BCG vaccination. If this vaccination has already been done, then a screening test for the presence of mycobacteria can be carried out no earlier than a month later. Other contraindications include:

If a negative result of the staged test was obtained, then the next Diaskintest can be carried out no earlier than two months later. If there is a disease and its treatment, the test is performed more often - up to three times a year.

This type of examination is prescribed directly by a TB doctor. The TB test should be carried out by specially trained nurses. Before the test, the patient must be examined by a general practitioner or pediatrician. The injection itself is carried out in a specialized dispensary or specially equipped medical rooms.

Rules for setting up the test

The test with Diaskin is carried out according to the same rules as the Mantoux reaction. The test is carried out according to the following rules:

Interpretation of results

The result of Diaskintest can only be assessed by a doctor or nurse who has undergone special training. The transverse size of the resulting papule (infiltrate) relative to the axis of the forearm and/or hyperemia are measured.

The size of hyperemia is taken into account as a result only in the absence of infiltration. The measurement is carried out using a ruler with millimeter divisions. All test results and their interpretation are divided into three categories:

1. Negative result.
2. Positive result.
3. Doubtful result.

Negative result

This response of the body is the norm (in adults and children) and is stated as a fact in the case of complete absence papules and/or hyperemia on the forearm. A slight “puncture reaction” of up to 2 mm may be observed.

A negative reaction may occur in the following individuals and population groups:

• the person is not infected with mycobacteria;
• the infection is in an inactive phase;
• The patient was completely cured of this disease.

If the test was performed on children, all preventive vaccinations are allowed for them only after receiving the test results.

Positive result

This result is taken into account if a papule of any size can be visually identified. A positive test is considered in the following situations (the size of the papule is taken into account):

What to do in this situation? All patients who have a positive test are subject to additional examination for tuberculosis. Mandatory fluorography (or radiography) of the lungs is performed. According to indications - CT scan of the affected organ.

Treatment with anti-tuberculosis drugs begins in the first days after receiving a positive result.

Therapy is prescribed by a TB doctor according to a specific scheme. Treatment is quite long - the norm is from 3-4 months to 2-3 years. It cannot be interrupted, since mycobacteria very quickly adapt to the drugs used.

When treating with anti-tuberculosis drugs, Diaskintest is given at intervals of one month. If the test is positive, then treatment is continued. If negative, preventive therapy is carried out for 1-2 months and treatment is stopped.

If the Diaskintest results are negative within two years, the patient is deregistered from the TB dispensary and is considered healthy. The norm for conducting a screening test for tuberculosis is once a year.

Questionable reaction

The test result is considered doubtful if there is no infiltration. Hyperemia may be slightly expressed.

A situation in which the Diaskintest is negative and the Mantoux test is positive (or vice versa) may be questionable. Results may vary with treatment. To make a correct diagnosis in this case, it is recommended to carry out PCR diagnostics. This analysis can reveal all hidden bacteria (works at the gene level). Its only drawback is its high cost.

From all of the above we can conclude: Diaskintest is proven and effective method diagnosis of tuberculosis. It is quite easy to use. Accounting for the sample does not cause any great difficulties. Given the current difficult situation with tuberculosis, every person who cares about their health should undergo this examination.

Diaskintest is a diagnostic solution designed to determine whether the test subject has tuberculosis. It is administered intradermally.

Diagnosis of tuberculosis is a rather complex multi-stage process. The incidence of this infection is quite high and the number of patients with tuberculosis is increasing every year. In order to speed up the process of identifying possible patients, there are screening methods. One of them is Diaskintest.

You can ask the question, but what? Yes, this diagnostic option with a long history of use is also used. However, the Mantoux test has one important drawback - an “unfriendly” attitude towards the BCG vaccine, which is reflected in possible unreliable results.

But Diaskintest, registered on August 11, 2008 (certificate No. LSR-006435/08), is free from this drawback.

For reference. Diaskintest is the trade name of a diagnostic method that allows you to determine the presence of an immune response to antigens entering the body.

Diagnosticums for diaskintest are obtained in laboratory conditions. To do this, E. coli are trained to produce two protein antigens of mycobacteria, by which the immune system recognizes a tuberculosis infection.

E. coli are normal microflora human body and do not pose any threat to health. They are trained by introducing genes responsible for the synthesis of the necessary two proteins.

For reference. Modified E. coli begin to produce mycobacterial antigens, which are used to prepare Diaskintest.

An extract of the necessary proteins is prepared and diluted with physiological solution in the required dilution. Standard sets Diaskintest already have the required dosage, where 0.1 ml is equal to one dose of antigen.

Specificity and sensitivity of the method

For reference. Specificity is an indicator that reflects the number of false positive responses.

According to statistics, up to 2 people out of 100 healthy people who take the test receive a false answer. This indicator is considered high in comparison with other research methods.

False-positive responses occur due to the fact that there are acid-fast bacteria that are similar in antigenic composition to.

For reference. These infectious agents do not cause a specific disease, but stimulate the formation of immunity against Koch bacillus antigens. The human immune system recognizes them as Mycobacterium tuberculosis, and therefore subsequently reacts to Diaskintest.

Sensitivity is the opposite of specificity. It determines how many false negative answers researchers receive per 100 samples taken.

For Diaskintest, the rate ranges from 4-12 false responses per 100 tuberculosis patients who underwent the study. This means that up to 12 people out of 100 with tuberculosis will receive a negative result after undergoing the diaskintest. This figure is considered high.

Thus, despite the presence of false-positive and false-negative responses, Diaskintest is considered a fairly specific and sensitive technique.

Purpose of Diaskintest

For reference. Diaskintest is necessary to assess the immune response to the introduction of Koch bacillus antigens.

The fact is that upon contact with any infectious agent, the human immune system produces specific cells and macromolecules. These include T lymphocytes and antibodies produced by B lymphocytes.

Upon first contact with an infection, in response to its antigens, the body begins to produce antibodies and train T-lymphocytes. The immune system has a memory for antigens, so upon repeated contact with the same infection, the immune response is already ready. The action of Diaskintest is based on this principle.

The test contains specific recombinant proteins of Mycobacterium tuberculosis. These proteins are antigens by which the immune system recognizes Koch bacilli. If the body has already encountered a mycobacterium, there are specific T-lymphocytes against these antigens.

For reference. Diaskintest is carried out using intradermal injection mycobacterial proteins. In the presence of immunity, T-lymphocytes rush to the injection site and cause a local allergic reaction. Objectively, this is manifested by local inflammation.

Immunity for tuberculosis is formed in two cases: after suffering primary tuberculosis in the past and with active tuberculosis in the present.

It is necessary to be able to differentiate these two options, since the diaskintest will show a positive result in both cases. If there is no immune response to the introduction of the antigen, then the result of the diaskintest will be negative, which may also indicate several conditions associated with both lack of contact with mycobacteria and profound suppression of the immune system.

Indications

There are few indications for prescribing Diaskintest. Most often it is performed on children for preventive purposes. In many countries, including Russian Federation, Diaskintest is used instead of the Mantoux test in children attending preschool and school institutions.

Regardless of the presence or absence of tuberculosis symptoms, all children are tested at school.

For children, the indication for an emergency test is the presence of symptoms of tuberculosis, for example, prolonged persistent cough or antibiotic-resistant pneumonia.

Attention! If a child has had a Mantoux test and it turns out to be positive, he should also have a diaskintest.

The informativeness of the test in this case is explained by the fact that persons who have never been in contact with wild strains of mycobacteria do not have immunity to the two diagnostic antigens used in the test.

If the reaction is positive, then the child has already become infected with tuberculosis. Either he is currently suffering from it, or he suffered from the primary form of tuberculosis and is now healthy.

It makes no sense to carry out this technique in adults for prophylactic purposes. Almost every person over 18 years of age has immunity to Mycobacterium tuberculosis.

Important. The indication for diaskintest in adults is the suspicion of an open form of tuberculosis.

An appointment for a test can be made when the following symptoms:

• the presence of an infiltrate or pathological focus in the lungs that cannot be treated with conventional antibiotics,
• persistent cough for more than two weeks,
• causeless increase in body temperature to subfebrile levels or emaciation.

Attention. Diagnostic value Diaskintest is acquired only if used in combination with other methods for diagnosing tuberculosis.

After treatment of tuberculosis, a test is also used to assess the effectiveness of the therapy.

Contraindications

Contraindications to the technique are:

• Infections, excluding those suspected of tuberculosis;
• Any chronic pathology in the stage of decompensation;
• Skin diseases that prevent the test from being performed on both hands;
• Allergic reactions tolerated at the time of the procedure;
• Introduction preventive vaccination less than a month before the test;
• Any form of epilepsy.

For reference. It is worth noting that impaired renal and liver function do not affect the test. In addition, Diaskintest is not contraindicated for pregnant and lactating women, but only if an active form of tuberculosis is suspected.

Sample frequency

Diaskintest is used annually for children for the purpose of early diagnosis of primary tuberculosis. If the child has not been vaccinated with the BCG vaccine, more frequent monitoring is necessary. Such children are tested at least once every six months.

For adults, there is no such periodicity. As a method of early diagnosis of active tuberculosis, Diaskintest is not very informative. Adults undergo a fluorographic examination annually, and a diagnostic test is carried out only if indicated.

For reference. Testing can be repeated after any period of time, if necessary.

Adverse reactions

Adverse reactions are extremely rare and are due to individual sensitivity to the drug. Such reactions include:

• Headache;
• Increased body temperature, usually to subfebrile levels;
• Weakness, fatigue;
• Nonspecific allergic reaction at the injection site.

The few side effects and a small percentage of occurrence are due to intradermal administration of the drug. Diagnosticum does not enter the systemic circulation, therefore it extremely rarely causes generalized reactions.

For reference. More often side effects associated with a violation of the diaskintest technique. In this case, extensive hematomas may form at the site of drug administration, generalized allergic reactions may develop, and in the elderly, blood pressure may increase.

The danger of diaskintest

This diagnostic method is considered relatively safe. The opinion that during diaskin you can become infected with tuberculosis is erroneous.

Diagnosticum does not contain mycobacteria or their tissues. Only two proteins carrying an antigenic load are introduced.

Important. These proteins cannot cause any disease other than an immune reaction. In addition, the drug does not even contain E. coli, on which the necessary proteins were grown. Only the sterile extract is administered.

The only possible danger is the risk of developing nonspecific allergic reaction. A hypersensitivity reaction is possible to any foreign protein.

In the case of Diaskintest, allergies are more often local and in rare cases generalized forms with symptoms typical of hypersensitivity are observed.

Diaskintest and Mantoux

The presence of immunity to Mycobacterium tuberculosis antigens can be detected using several methods. The most common of them at the moment are the Diaskintest and the Mantoux test. Both methods have the same mechanism of action and even method of administration.

In both cases, 0.1 ml of diagnosticum containing Koch bacilli antigens is injected intradermally.

For reference. The difference is that Diaskintest is a genetically engineered product. The proteins are grown artificially on other bacteria and then removed. The drug contains only two antigens, which are found only in virulent (dangerous) strains of mycobacteria.

Tuberculin for the Mantoux test is prepared by extracting proteins from weakened mycobacteria. The antigenic structure of tuberculin is larger than that of diaskintest.

The Mantoux test gives a positive reaction not only to virulent strains, but also to the immunity left by the BCG vaccine. In addition, tuberculin produces more cross-reactions with other types of bacteria.

Important. The sensitivity of both methods is the same. However, Diaskin is more specific; it gives fewer false-positive reactions than the Mantoux test.

The advantage of tuberculin diagnostics is that it recognizes earlier immunity than diaskintest. The reaction to Diaskintest antigens occurs later than to other mycobacterial proteins.

Sometimes both tests can be performed on different hands.

Preparation for the administration of Diaskin

This technique does not require specific preparation, but there are a number of conditions that must be met. First of all, they concern children who have reached the age of the next preventive revaccination.

Attention. After any vaccination, Diaskintest can be done no earlier than a month later. Therefore, it is more advisable to first carry out diagnosis and then revaccination.

The BCG vaccine cannot be administered a month before the test and immediately after it. This should be taken into account when revaccinating BCG in children aged seven years.

In addition, nonspecific allergic reactions in persons prone to them should be excluded. To do this, allergy sufferers are prescribed antihistamines in standard doses a week before the test, which lasts until the result is registered.

Adults should not drink alcohol for three days before the test and three days after it. There is no data on the effect of smoking on the results of the Diaskintest. In addition, after the test is performed, you can drive a car and take any previously prescribed medications.

Where is testing done?

Diaskintest is an invasive diagnostic technique that can only be performed by medical personnel. For children, the test is carried out in educational institutions according to the preventive examination schedule. Adults can contact their local physician, in which case the diaskintest will be carried out in the manipulation room of the clinic.

In addition, there are institutions dedicated to the prevention, diagnosis and treatment of tuberculosis. These include specialized dispensaries, sanatoriums, and research institutes. They also conduct outpatient visits and have tuberculosis prevention rooms. You can contact one of these institutions and have a diaskintest done by specialists.

Test procedure

The test can only be carried out by a specially trained nurse who knows the technique of intradermal administration of drugs. The fact is that administering the diagnosticum subcutaneously, intramuscularly or intravenously is a gross mistake. The test will be uninformative and may lead to complications.

The nurse checks the bottle for leaks, assesses the expiration date and appearance content. After this, 0.2 ml of the contents of the bottle is drawn into a tuberculin syringe. This volume is equal to two diagnostic doses.

For reference. The middle third of the inner surface of the forearm is disinfected with alcohol, after which 0.1 ml of diagnosticum is injected intradermally, which is equal to one diagnostic dose. When administered correctly, a “lemon peel” will form at the injection site.

Contact of injection site with water

Diaskintest, like the Mantoux test, can be wetted. Water does not react in any way with the diagnosticum and does not change the test result. But it is not recommended to take a bath before recording the result.

This is due to the fact that an infection can get into the wound left by the needle from the water. As a result, nonspecific inflammation will develop, which will blur the whole picture. For the same reason, you should not rub the injection site with a washcloth, soap or towel.

You should also exclude visiting saunas, baths, swimming pools and open reservoirs. You can shower without restrictions.

Results

The result is assessed exactly three days later, measuring the morphological elements remaining at the injection site with a ruler perpendicular to the axis of the forearm. The size and appearance of the morphological element are important.

Possible results

There are three types of reactions to drug administration:

• Negative. An injection mark remains and other morphological elements are absent.
• Doubtful. There is no subcutaneous induration at the injection site, but there is redness of varying sizes.
• Positive. A compaction of various diameters is felt under the skin. As a rule, it protrudes above the surface of the skin in the form of a nodule (papule).

A positive result is divided into varieties as follows:

• Weak – the compaction does not exceed 0.5 cm in diameter;
• Moderate – compaction from 0.6 to 0.9 cm in diameter;
• Pronounced – the diameter of the papule is from 1 to 1.5 cm;
• Hypersensitive – induration more than 1.5 cm or the presence of other morphological elements (pustules, crusts, inflammation of the lymphatic vessels).

Interpretation of the result

A negative result is observed if the body has never encountered Mycobacterium tuberculosis. In countries with a poor epidemic situation, a negative result is most often found in children.

Attention. In adulthood, a negative result means immunosuppression.

For example, it occurs in HIV-infected people in the AIDS stage even if they have active tuberculosis.

A questionable result does not give a clear answer about the strength of the immune system and requires a repeat test after 2-3 months.

For reference. A positive result means either the presence of immunity due to the fact that tuberculosis was previously suffered, or active disease at present.

As a rule, the severity of the reaction correlates with activity pathological process. Persons with a positive reaction are subject to further examination in order to make a final diagnosis.

Reaction by day

For reference. Immunity to mycobacteria develops in the form of delayed-type hypersensitivity. This means that the immune reaction to the administration of the drug will begin no earlier than in a day. However, due to the small dose of the drug, the response develops slowly.

A day after the test, hyperemia or a small thickening may appear, which gradually increases in size.

It reaches its maximum only on the third day.

The appearance of a reaction several hours after administration of the drug speaks in favor of a nonspecific reaction.

Allergy to Diaskintest

An allergy to Diaskin develops in less than a third of the subjects, which is due to the protein origin of the drug. A nonspecific allergic reaction develops along the hypersensitivity pathway immediate type and occurs a few minutes or hours after injection.

In this case, the following are observed:

• local itching,
• hyperemia of the injection site,
• possible formation of urticaria.

Less commonly, a generalized reaction occurs with lacrimation, runny nose, and swelling of the eyelids. Even less often, Quincke's edema appears or worsens bronchial asthma. If an allergic reaction occurs, take antihistamine and contact the doctor who referred you for diaskintest.

Bruising at the injection site

Bleeding or a small bruise is not a sign of a reaction. It occurs when a vessel has been damaged. Even if the injection technique is followed, the superficial vessels may be injured by the needle.

For reference. The bruise is not taken into account when assessing the results.

Positive test

In adults and children, a positive diaskintest result can be interpreted differently. In children, the first positive result is called a test turn. It means that the child has encountered Mycobacterium tuberculosis for the first time.

In this case, a primary infection develops, which, as a rule, is asymptomatic, leaving behind lasting immunity. In order to identify the danger of the disease for a particular child, a consultation with a phthisiatrician is necessary.

In adults, a positive result means that immunity to mycobacteria has already been formed. As a rule, people living in the CIS countries suffer from primary tuberculosis before they reach adulthood, because adults have immunity.

If the diaskintest gives a positive result in an adult, this can be considered normal. However, a pronounced reaction may also indicate active tuberculosis.

For reference. The more pronounced the immune response to the drug, the greater the chance that the patient has an active form of tuberculosis. Only a TB doctor can give a final conclusion after an additional examination.