One of the most dangerous bacteria is the Koch wand. It causes tuberculosis – a disease that has claimed many lives over many centuries.
The course of infection is such that at first the ailment either has no clear clinical manifestations, or they are very weak. These may be periods of weakness, increased fatigue, poor appetite, irritability, drowsiness, or, conversely, agitation.
Doctors call these manifestations symptoms of intoxication. At this point, it is especially important to start treatment in time, not allowing the pathogenic bacteria to “capture” the entire human body.
How to recognize the disease in time? What you need to not miss precious time?
For many years, for a screening, that is, a massive, rapid detection of possible infection with Koch’s bacillus, children over 1 year old once a year have an allergic skin test: a small dose of tuberculin is injected under the skin. This special preparation contains in its composition a fragment of mycobacterium tuberculosis weakened and treated with special preparations of mycobacterium tuberculosis. In response to the test reaction occurs.
The same, well-known Mantoux reaction.
Within three days at the injection site, the skin becomes denser and red, and the injection site swells slightly. It should be so. After examining the “button” and measuring its diameter with a transparent ruler, the doctor makes conclusions about whether the child is infected with Koch’s wand and if the action of the BCG vaccine, which is administered in early childhood, continues.
The larger the “button,” the larger the cells in the body that “know” about the tubercle bacillus.
If there is no seal at the injection site or its diameter is not more than 1 mm, the reaction is considered negative. The child is completely healthy, his body with a Koch wand is unfamiliar.
If this happens to the peanut at the age of about 7 years old, he may be prescribed BCG revaccination (the first one is still in the hospital).
The size of the “buttons” more than 15 mm means a positive reaction. And it can be either an allergic reaction to tuberculin, or evidence of infection with a tubercle bacillus. And here the task of the doctor becomes more complicated: he must determine what caused the positive reaction in the child.
The suspicion of infection with the Koch wand arises if the diameter of the “button” exceeds 17 mm. In this case, the child may be referred for consultation to the phthisiatrician and may be scheduled for additional examination.
The size of the “buttons” from 5 to 15 mm, depending on the age and individual characteristics of the organism, may indicate a normal reaction to the tuberculin test. So parents should take into account that the probability of a false positive result is not excluded.
In 2008, Diaskintest appeared in the arsenal of tools with which to pinpoint Koch’s infection with a stick. It was developed by Russian specialists – scientists from the Research Institute of Molecular Medicine of the 1st Moscow State University named after IM Sechenov. According to researchers, this sample has almost 100% sensitivity and responds only to Koch’s wand.
This dramatically reduces the likelihood of false positives (when using tuberculin, these occur in 40-60% of cases).
How did you manage to achieve this accuracy? The fact is that Diaskintest contains a protein that includes two antigens, which are present only in the Mycobacterium tuberculosis strains that cause the disease. These antigens are not present in the BCG vaccine strain, which is vaccinated in children to protect against tuberculosis.
Thus, the test result will be positive only if pathogens of tuberculosis multiply in the body.
Do Diaskintest in the same way as the Mantoux test. The drug is injected under the skin, in the place of injection forms a “button”.
After 72 hours, the doctor evaluates the results. If the patient is not infected, there will not be a papule in the injection site – a protruding dense skin area of bright pink color.
If there is a papule, its diameter is measured, and the phthisiatrician examines the child. He also makes the final conclusion whether the child needs treatment.
Who needs to carry out Diaskin test? According to the order of the Ministry of Health of Russia of December 29, 2014, Diaskintest is made annually to all children aged 8 to 17 years.
If a child belongs to a high risk group for tuberculosis, he should carry out such an examination 2 times a year. Outside the annual screening, the doctor will advise you to do such a test if the child, for example, coughs for no apparent reason for a long time or complains of pain in the legs, weakness, sweats a lot, has disturbed sleep, appetite, reduced attention and school performance. Diaskintest will also be needed when the karapuz keeps a little elevated (subfebrile) temperature for a long time or for unknown reasons the weight has decreased.
Use the test and for additional diagnostics, if you need to clarify the results of the Mantoux test. In this case, it can be carried out simultaneously with the Mantoux test, only on different hands (for example, the Mantoux test is done on the left, and Diaskintest on the right hand), and also after the Mantou test on the same hand.
Like the Mantoux test, Diaskintest does not require special training.
The body’s reaction to the Mantoux test or Diskintest becomes known 72 hours after the manipulation. To reduce the likelihood of errors, within 3 days you need to adhere to certain restrictions. There are no contraindications for showering and bathing, however, the injection site should not be rubbed and cosmetic preparations should be applied to it, for example, cream.
Sometimes the result of the test can be affected by the reaction to excessive sweating, for example, during exercise or because of tight clothing.