COMPARATIVE ANALYSIS OF IMMUNOLOGICAL DIAGNOSTIC TESTS IN CHILDREN LIVING IN HOUSEHOLD TUBERCULOSIS FOCI

Abstract

Objective: To evaluate and compare the results of immunological diagnostic tests in children living in family tuberculosis hotspots based on data from the Samarkand region. Materials and methods: The study was conducted from 2021 to 2024. It included 670 children aged 4 to 12 years who had received the BCG vaccine and had a positive Mantoux test with 2 TU of PPD-L tuberculin. All children underwent testing with the Diaskintest preparation as well as the Quantiferon test. Results: Based on the comprehensive examination results, children were divided into the following groups: Group I - 273 healthy children (40.7%); Group II - 120 (17.9%) patients with latent tuberculosis infection (LTI); Group III - 277 children with active pulmonary tuberculosis (41.4%). Discussion: The sensitivity results to PPD-L tuberculin with 2 TU do not provide sufficiently reliable information for differentiating between patients with LTI and active forms of tuberculosis in children. The high results of the Mantu test in the cohort of healthy children (23.8%) are noteworthy, while the average results of the tuberculin test with 2 TB were recorded in 53.4% of cases in the group of children with active forms of tuberculosis, as well as in 52.5% of the LTI cohort of children. One in five children with a difference in the positive results of the ATR test with a simultaneous negative result of the QFT test were classified as frequently and long-term ill children and suffered from ENT pathology. More than half of these children had a history of allergic pathology (54.5%) and metabolic disorders in the form of overweight and obesity (63.6%). Conclusions: in cases where the results of the ATP test are interpreted as false positive, it is necessary to use alternative methods - IGRA tests (Quantiferon).