[Statistically mapping modeling of the spread of rifampicin-resistant M. tuberculosis strains in different regions of the Kyrghyz Republic].

Mapping modeling of the distribution of rifampicin-resistant tuberculosis was made in different regions of the Kyrghyz Republic. The results of determination of rifampicin resistance in Mycobacterium tuberculosis (MBT) by the biochip test were used to examine 904 MBT DNA samples taken when examining the patients living in different regions of the Kyrghyz Republic: Bishkek (n = 323), the Chui (n = 185), Issyk-Kul (n = 68), Naryn (n = 75), Talas (n = 47), Osh (n = 65), Dzhalal-Abad (n = 90), and Batken (n = 51) Regions. Comparison of the distribution of drug-resistant forms of tuberculosis by different regions revealed that rifampicin-resistant MBT strains were more frequently encountered in the densely populated regions of the republic - Bishkek and the Chui Region. Rifampicin resistance in MBT was caused by mutations in codons 531, 526, 522, 516, 511, 513, 512, and 513 of the rpoB gene. At the same time, there was a predominant selection of MBT with mutations in codons 531, 526, 516, and 511 in the republic. The spectrum of mutant MBT strains occurring in some regions varied. The broadest spectrum of genetic variability was observed in Bishkek and the Chui Region. Thus, Bishkek and the Chui Region are the hot points of concentration of mutant rifampicin-resistant MBT strains.

[Analysis of mutations of multidrug-resistant M. tuberculosis strains in patients with tuberculosis in the Kyrghyz Republic].

Two hundred and seventy-eight M. tuberculosis DNA samples taken from patients with clinically confirmed pulmonary and extrapulmonary tuberculosis were studied. Mutations of the rpoB, inhA, katG, and ahpC genes were analyzed by using multiple drug-resistant (MDR) biochips. A hundred and twenty-nine (46%) rifampicin- and isoniazid-sensitive strains and 149 (54%) resistant ones were detected. Out of the 149 drug-resistant strains, resistance to one drug (rifampicin or isoniazid) was revealed in 7 (4.7%) and 48 (32.3%) cases, respectively. The strains simultaneously resistant to both drugs were detected in 94 (63%) cases. In the Republic of Kyrghyzstan, patients with drug-resistant pulmonary tuberculosis were observed to have more commonly multidrug-resistant strains (63%) than the strains resistant to one drug (rifampicin or isoniazid). In this republic, the main cause of rifampicin resistance of Mycobacterium tuberculosis is the Ser531-Leu mutation of the rpoB gene in codon 531 and the Ser315-->Thr of the katG gene in codon 315.

[Use of biological microchips in the determination of drug-resistance of Mycobacterium tuberculosis to rifampicin].

The present-day problems in tuberculosis control are associated with a difficulty in detecting Mycobacterium tuberculosis (MBT) in due time and in determining its drug sensitivity by conventional microbiological assays. The determination of the drug sensitivity of MBT takes much time from 2 weeks to 3 months, which fails to initiate and perform specific therapy timely. Molecular genetic techniques, including biochip analysis, yield results in 24-48 hours, which solves the problem of choosing and initiating adequate antibacterial therapy in the shortest possible time after tuberculosis is diagnosed. To assess the situation associated with the prevalence of rifampicin-resistant tuberculosis, by using the biochip analysis, the authors have examined 501 patients with tuberculosis who live in the Kyrghyz Republic. Drug resistance has been found in 40.3% of the examinees. At the same time, their primary and secondary drug resistance is 25.7 and 61.8%, respectively. In tuberculosis patients living in Kyrghyzstan, rifampicin resistance of MBT is more frequently due to mutations in 531 (59.2%), 526 (20.8%), and 516 (8.0%) codons in the rpoB gene.