Tuberculin test for more than a century remains the main means of diagnosis and prevention of tuberculosis . The drug Tuberculin (the exact name "Alttuberculin") is an extract of tuberculosis bacteria obtained under the influence of high temperatures, and therefore not capable of causing the disease. According to the reaction to the tuberculin test, an increase in the sensitivity of the organism to tuberculosis bacteria is observed, which is manifested as a kind of allergic reaction due to infection.
How is the tubulin test done?
In the first days of life in the hospital, each child is given a vaccine against the causative agent of tuberculosis - BCG. Then, the Mantoux test to detect primary infection of children is conducted annually, starting from one year, and up to 17 years. Adults take a tuberculin test at 22-23 years and 27-30 years before subsequent BCG revaccinations.
Order of the Ministry of Health of the Russian Federation No. 324 of 22.11.1995 specifies the technique for conducting a tuberculin test. To administer the drug, a special syringe of 0.1 ml is used. The drug is introduced into the body depending on the type of tuberculin test:
- skin;
- intradermally;
- subcutaneously.
Recently, most often Tuberculin is injected into the region of the forearm, the needle outlet must enter into the skin at the same time. After the injection of the drug, a papule (infiltrate) - a tubercle resembling a button is formed.
Analysis result
The result of the test is assessed by the doctor. In the presence of antibodies to tuberculosis, an allergy to the tuberculin test is observed: two to three days after the introduction of Tuberculin, a bright pink tight tubercle develops, and the skin becomes paler when pressed against the seal. The specialist conducts the measurement of the reaction from the injection on the third day after the procedure, while securing:
- Negative reaction is absence of infection, there is no condensation, as such, and reddening does not exceed 1 mm.
- Doubtful reaction - reddening in size 2-4 mm without
seals. This result is equal to the negative reaction. - A positive reaction is a tightness and redness of 5 mm or more. Size from 5 to 9 mm - mild reaction, 10-15 - medium, 15-16 mm - pronounced.
- Excessive reaction - more than 17 mm in children and from 21 mm in adults. Excessive reaction indicates the onset of the inflammatory process in the body.
For your information! With some diseases, including rheumatism with heart damage, subcutaneous injection of tuberculin is undesirable.