[Tuberculin diagnosis in children. Latent tuberculosis?]

The 2000-2006 results of tuberculin diagnosis made in a city numbering 10.5 million people were retrospectively analyzed on the basis of an epidemiological tuberculosis survey among children. The higher cut-offs are not helpful in interpreting the tuberculin test. With more than 5 mm, it is necessary to have criteria for clear differences between the active tuberculous process, inactive tuberculous changes, and recent or previous Mycobacterium tuberculosis infection. With the low prevalence of tuberculosis among children in a megapolis, the sensitivity of the method was 97.4%. Its specificity was 41.7%; out of these children, a risk group forms in 1% of cases and the children who had been referred by a pediatrician and had failed to be examined by a specialist at a tuberculosis dispensary. With positive and negative tests, the likelihood of the disease in a child is 0.01 and 99.9%, respectively. At the same time, morbidity in risk group children formed by the results of tuberculin tests is high and indicative of a need for searching for objective indicators (except for tuberculin diagnosis and history data) to identify the disease just before registration as a risk group. The practical value of chemotherapy for latent tuberculosis infection in the megapolis requires studies and evidence-based results. Preventive chemotherapy is currently the priority in preventing tuberculosis for individual risk groups (among the HIV-infected and those who are from tuberculosis infection foci).