Mantoux test

To perform the Mantoux test, special disposable tuberculin syringes with thin, short needles and a short, oblique cut are used.

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Indications for the Mantoux test

In case of mass tuberculin diagnostics, the Mantoux test with 2 TE is performed on all children and adolescents vaccinated with BCG, regardless of the previous result, once a year. The child receives the first Mantoux test at the age of 12 months. For children not vaccinated with BCG, the Mantoux test is performed from 6 months once every six months until the child receives the BCG vaccination, and then according to the generally accepted method once a year.

The Mantoux test can also be used for individual tuberculin diagnostics. It is carried out in the conditions of a children's polyclinic, somatic and infectious hospitals for differential diagnostics of tuberculosis and other diseases, in the presence of chronic diseases with a torpid, wave-like course, in the case of ineffectiveness of traditional treatment methods and the presence of additional risk factors for infection or tuberculosis (contact with a patient with tuberculosis, lack of vaccination against tuberculosis, social risk factors, etc.).

In addition, there are groups of children and adolescents who are subject to the Mantoux test twice a year in the general health care network:

• patients with diabetes mellitus, gastric ulcer and duodenal ulcer, blood diseases, systemic diseases. HIV-infected patients receiving long-term hormonal therapy (more than 1 month);
• with chronic non-specific diseases (pneumonia, bronchitis, tonsillitis), subfebrile temperature of unknown etiology;
• not vaccinated against tuberculosis, regardless of the child's age;
• children and adolescents from social risk groups who are in institutions (shelters, centers, reception centers) and who do not have medical documentation (upon admission to the institution, then twice a year for 2 years).

When conducting individual tuberculin diagnostics, the threshold of sensitivity to tuberculin is determined - the lowest concentration of tuberculin to which the body responds with a positive reaction. To determine the threshold of sensitivity to tuberculin, the intradermal Mantoux test is used with various dilutions of dry purified tuberculin.

In children with suspected specific eye damage, in order to avoid a focal reaction, it is advisable to begin tuberculin diagnostics with skin or intradermal tests with 0.01 and 0.1 TE.

Tuberculin skin tests (plaster, ointment) currently have more historical significance, they are used rarely, more often for the diagnosis of tuberculosis of the skin or in cases where for some reason it is impossible to use the more common skin and intradermal tuberculin tests. The Pirquet test is also rarely used.

The graduated skin test (GST) of Grinchar and Karpilovsky is performed when differential diagnostics is necessary, to clarify the nature of tuberculin allergy, and to evaluate the treatment being administered.

A test with subcutaneous administration of tuberculin is indicated when it is necessary to determine the activity of tuberculosis of the respiratory organs, as well as for etiological diagnosis and determination of the activity of tuberculosis in extrapulmonary locations.

Mantoux test procedure

The tuberculin ampoule is carefully wiped with gauze soaked in 70% ethyl alcohol, then the neck of the ampoule is filed with a knife for opening ampoules and broken off. Tuberculin is collected from the ampoule with a syringe and needle, which are then used to administer the Mantoux test. 0.2 ml of the drug is drawn into the syringe (i.e. 2 doses), then the solution is released to the 0.1 ml mark into a sterile cotton swab. It is unacceptable to release the solution into the protective cap of the needle or into the air, as this may lead to an allergic reaction of the medical personnel. After opening, the tuberculin ampoule is suitable for use for no more than 2 hours if stored under aseptic conditions.

The intradermal test is performed only in a procedure room. The patient is in a sitting position. The skin area on the inner surface of the middle third of the forearm is treated with a 70% solution of ethyl alcohol, dried with sterile cotton wool, tuberculin is injected strictly intradermally, for which the needle is directed with the cut upwards into the upper layers of the stretched skin parallel to its surface. After inserting the needle hole into the skin, 0.1 ml of the Tuberculin solution is injected from the syringe (i.e. one dose). The injection site is not treated with alcohol again, since the risk of infection of the injection site is low (PPD-L contains quinisole). With the correct technique, a papule in the form of a "lemon peel" with a diameter of at least 7-9 mm of a whitish color is formed in the skin, which soon disappears.

The Mantoux test is administered by a specially trained nurse as prescribed by a doctor. The response is assessed by a doctor or a trained nurse after 72 hours. The results are entered into the following record forms: No. 063/u (vaccination card). No. 026/u (child's medical record). No. 112/u (child's development history). The manufacturer, batch number, tuberculin expiration date, test date, administration of the drug into the right or left forearm, and test result (size of infiltrate or papule in millimeters, in the absence of infiltrate - hyperemia size) are noted.

If properly organized, 90-95% of the child and adolescent population of the administrative territory should be covered by tuberculin diagnostics annually. In organized groups, mass tuberculin diagnostics are carried out in institutions either by specially trained medical personnel or by the team method, which is preferable. With the team method, children's clinics form teams - two nurses and a doctor. For unorganized children, the Mantoux test is carried out in the conditions of a children's clinic. In rural areas, tuberculin diagnostics are carried out by district rural district hospitals and feldsher-midwife stations. Methodological guidance of tuberculin diagnostics is carried out by a pediatrician of the anti-tuberculosis dispensary (office). In the absence of an anti-tuberculosis dispensary (office), the work is performed by the head of the outpatient department for children (district pediatrician) together with the district phthisiologist.

In response to the introduction of tuberculin, a local, general and/or focal reaction develops in the body of a previously sensitized person.

• A local reaction is formed at the site of tuberculin administration and may manifest itself as hyperemia, papules, infiltrates, vesicles, bullae, lymphangitis, and necrosis. A local reaction has diagnostic significance in the case of cutaneous and intradermal administration of tuberculin.
• The general reaction is characterized by general changes in the human body and can manifest itself in the form of deterioration of health, increased body temperature, headaches, arthralgia, changes in blood tests (monocytopenia, dysproteinemia, slight acceleration of ESR, etc.). The general reaction most often develops with subcutaneous administration of tuberculin.
• Focal reaction develops in patients in the focus of a specific lesion - in tuberculosis foci of various localizations. In pulmonary tuberculosis, focal reaction may appear as hemoptysis, increased cough and catarrhal symptoms, an increase in the amount of sputum, chest pain; in extrapulmonary tuberculosis - an increase in inflammatory changes in the zone of tuberculosis lesion. Along with clinical manifestations, X-ray examination may show an increase in perifocal inflammation around tuberculosis foci. Focal reaction is more pronounced with subcutaneous administration of tuberculin.

The Mantoux test result is assessed after 72 hours. The diameter of the papule or hyperemia in millimeters is measured with a transparent ruler. The ruler is positioned perpendicular to the axis of the forearm. For correct interpretation of the results, not only a visual assessment of the reaction is necessary, but also palpation of the tuberculin injection site, since with a weakly expressed papule, slightly elevated above the skin level, and in the absence of hyperemia, the reaction can be assessed as negative. With hyperemia extending beyond the papule, light pressure with the thumb on the reaction area allows you to briefly remove the hyperemia and measure only the papule.

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Pirquet test

The test is a cutaneous application of dry purified tuberculin diluted to a content of 100 thousand TE in 1 ml. Scarification of the skin is performed through a drop of this tuberculin solution applied to the skin. The result is assessed after 48-72 hours.

Evaluation of Mantoux test results

The test results can be assessed as follows:

• negative reaction - complete absence of infiltrate (papule) and hyperemia, the presence of a prick reaction of 0-1 mm is allowed;
• questionable reaction - infiltrate (papule) measuring 2-4 mm or hyperemia of any size without infiltrate;
• positive reaction - infiltrate (papule) 5 mm or more in size, as well as vesicles, lymphangitis, and lesions (several papules of any size around the site of tuberculin injection):
  • weakly positive - papule size 5-9 mm:
  • medium intensity - papule size 10-14 mm;
  • pronounced - papule size 15-16 mm;
  • hyperergic - papule size 17 mm and above in children and adolescents, 21 mm and above in adults, as well as vesicular-necrotic reactions, lymphangitis, and sloughing, regardless of the papule size.

In our country, the entire child population is subject to vaccination against tuberculosis at certain times, according to the vaccination calendar. After the introduction of the BCG vaccine, DTH also develops in the body, as a result of which reactions with 2 TE of purified tuberculin in a standard dilution become positive - the so-called post-vaccination allergy (PVA) develops. The appearance of a positive reaction as a result of spontaneous infection of the body is regarded as an infectious allergy (IA). Studying the results of Mantoux tests in dynamics in combination with data on the timing and frequency of BCG vaccinations, as a rule, in the overwhelming majority of cases allows for differential diagnostics between PVA and IA.

Positive results of the Mantoux test are considered as PVA in the following cases:

• the appearance of positive and questionable reactions to 2 TE during the first 2 years after previous vaccination or revaccination with BCG;
• Correlation of the size of the papule after tuberculin administration and the size of the post-vaccination BCG sign (scar); a papule up to 7 mm corresponds to scars up to 9 mm, and a papule up to 11 mm - to scars over 9 mm.

The Mantoux test result is considered as IA (GRT) in the following cases:

• transition of a negative reaction to a positive one, not associated with BCG vaccination or revaccination. - "conversion" of tuberculin tests;
• an increase in the size of the papule by 6 mm or more over the course of one year in tuberculin-positive children and adolescents;
• gradual, over several years, increase in sensitivity to tuberculin with the formation of reactions of moderate intensity or severe reactions;
• 5-7 years after vaccination or revaccination with BCG, persistent (for 3 years or more) sensitivity to tuberculin at the same level without a tendency to fade - monotonous sensitivity to tuberculin;
• fading of sensitivity to tuberculin after previous IA (usually in children and adolescents who were previously observed by a phthisiopediatrician and received a full course of preventive treatment).

Based on the results of mass tuberculin diagnostics in dynamics among children and adolescents, the following contingents are distinguished:

• uninfected - these are children and adolescents who have annual negative Mantoux test results, as well as adolescents who have PVA;
• children and adolescents infected with Mycobacterium tuberculosis.

For early detection of tuberculosis and its timely prevention, it is important to register the moment of primary infection of the body. This does not cause difficulties when negative reactions turn into positive ones, not associated with vaccination or revaccination with BCG. Such children and adolescents should be referred to a phthisiatrician for timely examination and preventive treatment. Preventive specific treatment for 3 months in the early period of primary infection prevents the development of local forms of tuberculosis. Today, the share of tuberculosis in children and adolescents detected in the "turning point" period is from 15 to 43.2%.

The development of tuberculosis in children and adolescents with increasing sensitivity to tuberculin by 6 mm or more per year has been proven. It was proposed that such children and adolescents also be treated prophylactically for 3 months

An increase in sensitivity to tuberculin in an infected child to hyperergy indicates a high risk of developing local tuberculosis. These patients are also subject to consultation with a phthisiologist with an in-depth examination for tuberculosis and a decision on the appointment of preventive treatment.

Children and adolescents with monotonous reactions to tuberculin in combination with two or more risk factors for the development of tuberculosis are also subject to consultation with a phthisiatrician with an in-depth examination for tuberculosis.

If it is difficult to interpret the nature of sensitivity to tuberculin, children are subject to preliminary observation in group 0 of the dispensary registration with mandatory implementation of treatment and preventive measures in the pediatric area (hyposensitization, sanitation of foci of infection, deworming, achieving a period of remission in chronic diseases) under the supervision of a pediatric phthisiatrician. A repeat examination in the dispensary is carried out after 1-3 months.

The study of tuberculin sensitivity in children and adolescents with active forms of tuberculosis, as well as those infected (based on mass and individual tuberculin diagnostics in combination with clinical and radiological data) made it possible to propose an algorithm for monitoring patients depending on the nature of tuberculin sensitivity and the presence of risk factors for tuberculosis.

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