The Russian Federation is a high-tuberculosis burden country with high rates of multidrug and extensive drug resistance (M/XDRTB) especially in HIV co-infected patients. Rapid and reliable diagnosis for detection of resistance to second-line drugs is vital for adequate patient management.We evaluated the performance of the GenoType® MTBDRsl (Hain Lifescience GmbH, Nehren, Germany) assay on smear-positive sputum specimens obtained from 90 HIV-infected MDR TB patients from Russia. Test interpretability was over 98%. Specificity was over 86% for all drugs while sensitivity varied being the highest (71.4%) for capreomycin and lowest (9.4%) for kanamycin probably due to presence of mutations in the eis gene. The sensitivity to detect XDRTB was 13.6% increasing to 42.9% if kanamycin (not commonly used in Western Europe) was excluded. The assay is a highly specific screening tool for XDR detection in direct specimens from HIV co-infected TB patients, but cannot be used to rule out XDR TB.
Kontsevaya I, Ignatyeva O, Nikolayevskyy V, Balabanova Y, Kovalyov A, Kritsky A, Matskevich O, Drobniewski F. Rapid diagnosis of extensively-drug resistant TB in HIV co-infected patients: diagnostic accuracy of the GenoType(R) MTBDRsl assay. J Clin Microbiol. 2012 Nov 14. [Epub ahead of print]