Mem Inst Oswaldo Cruz, Rio de Janeiro, 112(11) November 2017
Correlation between the BACTEC MGIT 960 culture system with Genotype MTBDRplus and TB-SPRINT in multidrug resistant Mycobacterium tuberculosis clinical isolates from Brazil
1Universidade Federal de Minas Gerais, Faculdade de Medicina, Departamento de Clínica Médica, Programa de Pós-Graduação em Infectologia e Medicina Tropical, Belo Horizonte, MG, Brasil
2Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório de Biologia Molecular Aplicada a Micobactéria, Rio de Janeiro, RJ, Brasil
3Universidade Federal de Minas Gerais, Faculdade de Farmácia, Departamento de Farmácia Social, Laboratório de Biologia Molecular e Saúde Pública, Belo Horizonte, MG, Brasil
4Fundação Ezequiel Dias, Belo Horizonte, MG, Brasil
5Centre Muraz, Bobo-Dioulasso, Burkina Faso
6Institut for Integrative Cell Biology, UMR9198 CEA-CNRS-UPSaclay, Orsay, France
7University Paris-Sud, Beamedex SAS, Orsay, France
BACKGROUND The accurate detection of multidrug-resistant tuberculosis (MDR-TB) is critical for the application of appropriate patient treatment and prevention of transmission of drug-resistant Mycobacterium tuberculosis isolates. The goal of this study was to evaluate the correlation between phenotypic and molecular techniques for drug-resistant tuberculosis diagnostics. Molecular techniques used were the line probe assay genotype MTBDRplus and the recently described tuberculosis-spoligo-rifampin-isoniazid typing (TB-SPRINT) bead-based assay. Conventional drug susceptibility testing (DST) was done on a BACTECTM MGIT 960 TB.
METHOD We studied 80 M. tuberculosis complex (MTC) clinical isolates from Minas Gerais state, of which conventional DST had classified 60 isolates as MDR and 20 as drug susceptible.
FINDINGS Among the 60 MDR-TB isolates with MGIT as a reference, sensitivity, specificity, accuracy, and kappa for rifampicin (RIF) resistance using TB-SPRINT and MTBDRplus, were 96.7% versus 93.3%, 100.0% versus 100.0%, 97.5% versus 95.0% and 0.94 versus 0.88, respectively. Similarly, the sensitivity, specificity, accuracy, and kappa for isoniazid (INH) resistance were 85.0% and 83.3%, 100.0% and 100.0%, 88.8% and 87.5% and 0.74 and 0.71 for both tests, respectively. Finally, the sensitivity, specificity, accuracy, and kappa for MDR-TB were 85.0% and 83.3%, 100.0% and 100.0%, 88.8% and 87.5% and 0.74 and 0.71 for both tests, respectively.
MAIN CONCLUSIONS Both methods exhibited a good correlation with the conventional DST. We suggest estimating the cost-effectiveness of MTBDRplus and TB-SPRINT in Brazil.