Туберкулез и болезни лёгких (Nov 2021)
Immunodiagnostic Tests in the Assessment of Specific Sensitization to <i>M. tuberculosis</i> in Children under the Current Epidemical Situation
Abstract
The objective: to study the degree of specific sensitization according to the results of intradermal immunodiagnostic tests in children with different manifestations of tuberculosis infection under the current epidemic situation.Subjects and Methods. The degree of tuberculin sensitization was studied in 299 children from different age groups (0-14 years old) who were registered for dispensary follow-up in 2018-2019.Based on the results of a tuberculosis recombinant allergen test (TRA), the degree of specific sensitization was studied in children with tuberculin tests conversion (n = 102) and infected with Mycobacterium tuberculosis (MTB) for 2 years or more (n = 165) exposed to tuberculous infection in their families and from healthy environment, and 145 patients under 14 years old with local respiratory tuberculosis.Results. Moderate sensitization to tuberculin predominated in children with converted tuberculin test exposed to tuberculous infection in their families and those from healthy environments. According to the results of TRA test, a high degree of sensitization was observed 4.7 times more frequently in children with tuberculin test conversion exposed to tuberculosis in their families. In children from healthy environments, negative responses to TRA test were registered 2.4 times more frequently. In 73% of children infected with MTB, results of annual Mantoux tests didn’t differ much. Hyperergic reactions to TRA test in infected children exposed to tuberculous infection were 10 times more frequent than in those from healthy environments. A direct correlation was found between the high degree of sensitization to active M. tuberculosis and exposure to a tuberculosis case with a positive result of sputum test (χ2 < 0.001, p < 0.05). In the case of converted tuberculin test and infection with M. tuberculosis for 2 years or more, pronounced and hyperergic reactions to TRA test were registered with equal frequency and did not depend on the timing and duration of infection. A high risk factor and predictor of the disease development is high sensitization of the host to active M. tuberculosis which is found in patients with tuberculosis using TRA test six times more frequently versus Mantoux test (OR 5.951, 95% CI 3.548 and 9.981). The demonstrated results are important for the identification of children facing a high risk to develop active tuberculosis and preventive treatment prescription.
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