Open AccessMolecular detection of multidrug resistance pattern and associated gene mutations in M. tuberculosis isolates from newly diagnosed pulmonary tuberculosis patients in Addis Ababa, Ethiopia
Author(s) -
Melaku Tilahun,
Ezra Shimelis,
Teklu Wogayehu,
Gebeyehu Assefa,
Getachew Wondimagegn,
Alemayehu Mekonnen,
Tsegaye Hailu,
Kidist Bobosha,
Abraham Aseffa
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0236054
Subject(s) - inha , rpob , isoniazid , rifampicin , tuberculosis , mycobacterium tuberculosis , sputum , drug resistance , extensively drug resistant tuberculosis , genotype , medicine , multiple drug resistance , virology , polymerase chain reaction , gene mutation , multi drug resistant tuberculosis , biology , microbiology and biotechnology , gene , mutation , genetics , pathology
Multi-drug resistance is a major challenge in the control of tuberculosis. Despite newer modalities for diagnosis and treatment, people are still suffering from this disease. Understanding the common gene mutations conferring rifampicin and isoniazid resistance is crucial for the implementation of effective molecular tools at local and national levels. Hence, this study aimed to evaluate the molecular detection of rifampicin and isoniazid-resistant gene mutations in M . tuberculosis isolates in Addis Ababa, Ethiopia. Method Health Center-based cross-sectional study was conducted between January and September 2017 in Addis Ababa, Ethiopia. The collected sputum samples were processed for mycobacterial isolation and Region of difference 9 based polymerase chain reaction for species identification. To characterize the rifampicin and isoniazid-resistant M . tuberculosis isolates, a molecular genetic assay (GenoType MTBDR plus ) was used; the assay is based on DNA-STRIP technology. Result Culture positivity was confirmed in 82.6% (190/230) of smear-positive newly diagnosed pulmonary tuberculosis cases enrolled in the study. From 190 isolates 93.2% were sensitive for both rifampicin and isoniazid, and 6.8% of the isolates were resistant to at least one of the tested anti-TB drugs. Gene mutations were observed in all studied multidrug resistance-associated gene loci ( rpoB , katG , and inhA ). Two isolates exhibited heteroresistance, a mutated, as well as wild type sequences, were detected in the respective strains. MDR-TB case was observed in 1.1% (2/190) of the cases. All the MDR-TB cases were positive for HIV and found to have a history of prior hospital admission. Conclusion In our finding a relatively high prevalence of any drug resistance was observed and the overall prevalence of multidrug-resistant tuberculosis was 1.1%.The majority of drug-resistant isolates demonstrated common mutations. Heteroresistant strains were detected, signaling the existence of an M . tuberculosis population with variable responses to anti-tuberculosis drugs or of mixed infections.