What Mantoux Reaction Shows

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What Mantoux Reaction Shows
What Mantoux Reaction Shows

Video: What Mantoux Reaction Shows

Video: TB Skin Test - Mantoux Method 2022, December
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For early diagnosis of tuberculosis, children are annually given a Mantoux test in clinics, kindergartens and schools. There are often cases when, with a positive result, parents have to consult with specialists.

What Mantoux Reaction Shows
What Mantoux Reaction Shows

What is the Mantoux test

The Mantoux skin test is a kind of immunological test for the presence of tuberculosis infection in the body. In addition, this reaction is used to confirm tuberculosis and to monitor the effectiveness of treatment with a previously established diagnosis. This method has several names - Mantoux test, tuberculin test, PPD test. When conducting the test, tuberculin is used - an extract from weakened mycobacterium tuberculosis. The Mantoux test is done once a year for children, starting from the first year of life. If the child took Aflubin before the test, this will not affect its results in any way.

If there are contraindications for conducting a Mantoux test (allergic reactions or skin diseases), a laboratory blood test can be performed to determine IgA, IgM and IgG antibodies to the causative agent of tuberculosis.

How is the Mantoux test carried out

The principle of setting the sample consists in the intradermal administration of scanty doses of tuberculin. At the injection site, a specific inflammatory reaction occurs, caused by the accumulation of T-lymphocytes - blood cells "responsible" for anti-tuberculosis immunity. Fragments of mycobacteria, as it were, attract lymphocytes to themselves. If a person previously had a chance to "get acquainted" with a real causative agent of tuberculosis, then there will be more such lymphocytes, and inflammation will manifest itself more intensely. In this case, the reaction will be "positive", the inflammation will exceed the natural reaction of the body caused by the injection itself. The Mantoux test is not carried out on the same day as prophylactic vaccinations.

It is important to remember that the Mantoux test is not a vaccine. It should be carried out to the child even if, for some reason, he is exempted from preventive vaccinations.

How are the results of the Mantoux test evaluated

72 hours after the test, the diameter of the formed papule is measured, which makes it possible to assess the state of immunity against the tubercle bacillus. In this case, only the size of the seal itself is taken into account, and not the redness around it. If the seal does not exceed 1 mm, the reaction is considered negative, which means that mycobacteria have never entered the body. However, it should be borne in mind that the same result can be obtained when infected with tuberculosis in immunocompromised patients. If the compaction does not exceed 4 mm, the result is questionable. If the diameter of the seal is 5-16 mm, the reaction is positive, and it is possible that the person already has immunity against tuberculosis. In this case, a consultation with a phthisiatrician is required.

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