Nested reverse transcriptase–polymerase chain reactions targeting the messenger RNA of icl2, hspx, and rRNAP1 genes to detect viable Mycobacterium tuberculosis directly from clinical specimens

This study was aimed at the optimization and application of nested reverse transcriptase–polymerase chain reactions targeting the messenger RNA of the icl 2, hspx, and rRNAP1 genes directly from sputum specimens, and their evaluation against the culture by the BACTEC MicroMGIT mycobacterial culture system. Sputum samples (n =203) from clinically suspected tuberculosis patients and 30 control specimens (clinically proven viral or bacterial infections other than tuberculosis) were included in this study. The mycobacterial culture was performed by the BACTEC MicroMGIT system following the manufacturer’s instructions. The primers for nested reverse transcriptase–polymerase chain reaction targeting icl 2, hspx, and rRNAP1 genes were indigenously designed using the Primer-BLAST software, and optimized for sensitivity and specificity. Nested targeting icl 2, hspx, and rRNAP1 genes respectively. In addition, icl 2, hspx, and rRNAP1 genes were able to pick up 63.9%, 67.2%, and 58.75%, respectively, of culture-negative sputum specimens collected from clinically suspected tuberculosis patients. However, three (1.4%) were negative for nested reverse transcriptase–polymerase chain reactions, but M. tuberculosis culture positive. All the 30 controls were negative for culture by the BACTEC MicroMGIT method and all three nested reverse transcriptase–polymerase chain reactions. The novel nested reverse transcriptase–polymerase chain reactions targeting icl 2, hspx, and rRNAP1 gene...
Source: International Journal of Mycobacteriology - Category: Infectious Diseases Source Type: research