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The article describes a retrospective study of the results of microbiological and molecular genetic tests of 685 M. tuberculosis cultures isolated from 685 adult tuberculosis patients registered for dispensary follow-up in Moscow in 2014.The following was identified during the study: phenotypic drug resistance (FDR) of MTB to rifampicin, isoniazid, fluoroquinolones, kanamycin, amikacin, and capreomycin in groups of patients with different treatment history; the frequency of FDR to the above anti-tuberculosis drugs in strains with mutations being drug resistance markers; the frequency of various mutations in case of FDR of mycobacteria in the patients from different groups; the relationship of FDR or the presence of a particular mutation with various characteristics of the patients and their treatment history.The history of previous treatment was determined as statistical significance to provide the greatest influence on the spread of drug resistant MTB: patients undergoing repeated treatment had FDR more often and also a much more pronounced variety of mutations being markers of FDR to certain anti-tuberculosis drugs.The results of the study showed that the detection of genetic mutations in MBT associated with FDR was a reliable tool for predicting phenotypic resistance and should be used as the main method for selecting anti-tuberculosis drugs when compiling the etiotropic therapy regimen.

Aim. Determination of critical concentration for chemotherapy drugs, widely used for tuberculosis treatment, for use in Mycobacterium tuberculosis drug sensitivity results evaluation by Sensititre MycoTB test-system. Materials and methods. Minimal inhibiting concentration (MIC) of isoniazid, rifampicin, streptomycin, ethambutol, amikacin, kanamycin, ofloxacin and moxi-floxacin against conditionally sensitive and conditionally resistant strains of tuberculosis mycobacteria (TBM), isolated from various diagnostic material, obtained from patients with various forms of lung tuberculosis being treated in MCSPCTC hospital and dispensaries for tuberculosis control of Moscow, were studied in Sensititre MycoTB test system. Results. Critical concentration of chemotherapy drugs for MycoTB test system was determined as a result of the obtained MIC values analysis as the minimal concentration that suppressed growth of 95% of sensitive strains and does not obstruct growth of 95% of resistant. The following MIC values were established: streptomycin - 1.0, isoniazid - 0.25, rifampicin - 1.0, ethambutol - 4.0, ofloxacin - 2.0, moxifloxacin - 0.25, kanamycin - 2.5 and amikacin - 1.0 pg/ml. Conclusion. The developed critical concentration of the mentioned preparations is currently used for evaluation of sensitivity/ resistance of TBM clinical isolates from MCSPCTC.

The article presents efficiency comparison of Sensititre test system and culture methods of Bactec 960 and Lowenstein-Jensen medium for drug susceptibility testing of tuberculosis mycobacteria.Cultures of M. tuberculosis of 137 patients have been studied. It has been found out that the part of coinciding results is fairly big for drug susceptibility testing by test system of Sensititre MycoTB and other methods. This system has the advantages related to standard procedures and capacity of drug susceptibility testing (degree) to 12 drugs simultaneously within a short period of time (7-14 days). Drug susceptibility testing of M. tuberculosis by testing system of Sensititre MycoTB is simpler from technical point of view compared to all other systems. Sensititre MycoTB has been tested abroad and in MSPCT and certified and it can be used for the clinical practice.

Mutations in the rpoB, katG, inhA, oxyR/ahpC genes in rifampicin- and isoniazid-resistant M. tuberculosis strains isolated from residents of Moscow, Astrakhan', and Moldova Republic were studied by molecular biological methods (heteroduplex analysis, single strand conformational polymorphism, biochips). Twenty-five combinations of mutations were detected. Some differences in the type distribution of detected mutations were found. The use of biochips is the most perspective method for determining the type of mutation. [ABSTRACT FROM AUTHOR]