[The quality of bacteriological detection and determination of drug sensitivity of Mycobacterium tuberculosis by the participants of the External Clinical Laboratory Study Quality Assessment made by the Federal System in 2002-2003].

The paper presents the results of the assessment of the quality of cultural detection and determination of Mycobacterium tuberculosis (MBT) sensitivity at Russia's public health laboratories, which has been made by the Federal System for External Assessment of the Quality of Clinical Laboratory Studies in 2002-2003. The "Bacteriological Detection" Section involved 102 laboratories, of them 57 laboratories also participated in the section "Detection of Drug Resistance". Sixty-three laboratories operated as part of specialized tuberculosis-controlling service facilities and 39 laboratories worked as part of general medical care therapeutic-and-prophylactic institutions. A set of 5 lyophilized samples containing 2.5 x 10(6) M. tuberculosis H37Rv (n = 1); 2.5 x 10(4) M. tuberculosis H37Rv (n = 2); M. fortuitum (n = 1); E. coli in the mixture with autoclaving-killed M. tuberculosis H37Rv (n = 1). 77% of the laboratories could detect in the cultural sample with a high content of M. tuberculosis, by obtaining a correct result; 85% revealed MBT if only in every three MBT-containing samples; 15% of the laboratories could not find MBT in none of the three positive samples. 12% of the laboratories took the growth of microorganisms in the M. fortuitum-containing sample for that of M. tuberculosis. 58% of the laboratories obtained correct results if only in one sample containing M. tuberculosis H37Rv; 42% reported the detection of resistance to one or several antituberculous drugs in the samples containing the drug-sensitive strain H37Rv (a false drug resistance). All the results of determination of drug resistance (DR) in the M. fortium-containing sample were correct. The findings suggest that it is necessary to increase the professional competence of laboratory personnel to the level that ensures the adequate of fulfillment of the standard protocols for detecting MTB and determining DR, which have been introduced by the Ministry of Health of the Russian Federation through its order No. 109 on March 21, 2003.