Phenotypic and Genotypic Analysis of Multidrug-Resistant<i>Mycobacterium tuberculosis</i>Isolates from Sudanese Patients

Abstract

<i>Background.</i> Currently, mutations in <i>rpoB</i>, <i>KatG</i>, and <i>rrs</i> genes and <i>inhA</i> promoter were considered to be involved in conferring resistance to rifampicin, isoniazid, and streptomycin in <i>Mycobacterium tuberculosis</i> (MTB). <i>Objective.</i> The aims of this study were to detect the prevalence of first-line tuberculosis (TB) drug resistance among a group of previously treated and newly detected TB patients, to determine the association between prevalence of multidrug resistance (MDR) and demographic information (age and sex), to explain genes correlated with MDR <i>Mycobacterium tuberculosis</i>, and to characterize MTB via 16S ribosomal RNA (16S rRNA) analysis. <i>Methods.</i> A hundred MTB isolates from Sudanese pulmonary TB patients were included in the study. The proportional method of drug susceptibility test was carried out on Löwenstein-Jensen media. Multiplex PCR of <i>rpoB</i> and <i>KatG</i> genes and <i>inhA</i> promoter was conducted; then <i>rrs</i> genes were amplified by conventional PCR and were sequenced. The sequences of the PCR product were compared with known <i>rrs</i> gene sequences in the GenBank database by multiple sequence alignment tools. <i>Result.</i> The prevalence of MDR was 14.7% among old cases and 5.3% among newly diagnosed cases. <i>Conclusion.</i> Mutations in <i>rrs</i> could be considered as a diagnostic marker.