RT Journal Article SR Electronic T1 Novel sequence-based assay for detection of pyrazinamide-resistant mycobacterium tuberculosis in clinical specimens from patients with pulmonary tuberculosis in Russia JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP p1818 VO 38 IS Suppl 55 A1 Maria Alvarez Figueroa A1 Maria Gordukova A1 Galina Lobashova YR 2011 UL http://erj.ersjournals.com/content/38/Suppl_55/p1818.abstract AB Pyrazinamide (PZA) is an important first-line antituberculous drug used in all regimens recommended by the WHO. However PZA susceptibility testing is not routinely performed in many laboratories so comprehensive surveillance studies of pyrazinamide resistance are rare. The aim of our study was to determine the occurrence of PZA-resistant M.tuberculosis. We developed the diagnostic kit based on direct sequencing of pncA gene that was expected to detect all type of mutations. We have examined 143 respiratory specimens obtained from 140 Russian patients with pulmonary tuberculosis. All patients have been classified into 5 groups depending on duration of treatment. The first group consists of patients with newly diagnosed tuberculosis who did not received antituberculous drugs previously or taken them less than a month. The second group included patients from 1 to 3 months of such treatment. PZA-resistance has been found in 9 (10.3%) cases from 87 patients of the first group. The frequency of PZA-resistance of patients from the second group has been amounted to 41.6%. In half of these cases we found heterogeneous populations of bacilli consisted of wild and mutation types. PZA-resistance strains were detected in 7 (36.8%) of 19 patients from the third group with a duration of treatment from 3 to 6 months, in 6 (75.0%) of 8 patients with a duration of treatment from 6 to 9 months, and in 4 (80.0%) of 5 patients receiving antituberculous drugs from 9 to 12 months. These data suggest that the sequencing assay may be useful for the direct and rapid detection of PZA-resistant M.tuberculosis in clinical specimens.