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The spectrum of drug-resistance of rifampicin-resistant M. tuberculosis strains to other first-line antituberculous drugs was studied. Streptomycin resistance was found to be prevalent in the structure of monoresistance. Resistance to two agents--isoniazid and streptomycin--was more common in the structure of polyresistance; that to a combination of isoniazid, rifampicin, and streptomycin was seen in the structure of multidrug resistance. The rifampicin-resistant strains were also resistance to isoniazid and streptomycin in 95.1 and 98.7% of cases, respectively. Resistance to isoniazid, streptomycin, and ethambutol occurs more frequently when cytosine is substituted for thymidine (TCG-->TTG) in codon 513 of the rpoB gene.

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.

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.