1
|
Norouzi F, Moghim S, Farzaneh S, Fazeli H, Salehi M, Nasr Esfahani B. Significance of the coexistence of non-codon 315 katG, inhA, and oxyR-ahpC intergenic gene mutations among isoniazid-resistant and multidrug-resistant isolates of Mycobacterium tuberculosis: a report of novel mutations. Pathog Glob Health 2021; 116:22-29. [PMID: 34086544 DOI: 10.1080/20477724.2021.1928870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Tuberculosis (TB) is a global threat due to the emergence and spread of drug-resistant Mycobacterium tuberculosis (MTB). Isoniazid (INH) is the main antibiotic used for prevention and treatment of TB. Evidence shows that accumulated mutations can produce INH resistant (INHR) strains, resulting in the progression of multidrug-resistant (MDR) TB. Since point mutations in katG gene, inhA gene, and oxyR-ahpC region correlated with the INH resistance, in this study, we aimed to identify mutations in these three genes in INHR and MDR clinical isolates of MTB by Sanger DNA sequencing analysis. Thirty-three out of 438 isolates were resistant, including 66.7% INHR and 30.3% MDR isolates. In the katG gene, 68.2% INHR isolates had non-synonymous point mutations, mainly R463L (63.6%), and non-synonymous point mutation KatG L587P was seen in one of the MDR isolate. A novel silent substitution L649L was identified in the inhA gene of the MDR isolates. The oxyR-ahpC intergenic region g-88a common mutations (63.6%) in INHR and two distinct novel mutations were found at positions -76 and -77 of the oxyR-ahpC intergenic region. The coexistence of katG non-codon 315 with oxyR-ahpC intergenic region mutations was highly frequent in INHR 59.1% and MDR isolates 70%. Since mutations of all three genes 95.5% lead to the detection of INHR, they might be useful for molecular detection. Our results indicated the continuous evolution and region-specific prevalence of INH resistance. Overall, identification of new mutations in INH resistance can improve the available strategies for diagnosis and control of TB.
Collapse
Affiliation(s)
- Fatemeh Norouzi
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Sharareh Moghim
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - ShimaSadat Farzaneh
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hossein Fazeli
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mahshid Salehi
- Regional Tuberculosis Reference Laboratories in Isfahan, Isfahan, Iran
| | - Bahram Nasr Esfahani
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
2
|
Welekidan LN, Skjerve E, Dejene TA, Gebremichael MW, Brynildsrud O, Tønjum T, Yimer SA. Frequency and patterns of first- and second-line drug resistance-conferring mutations in Mycobacterium tuberculosis isolated from pulmonary tuberculosis patients in a cross-sectional study in Tigray Region, Ethiopia. J Glob Antimicrob Resist 2020; 24:6-13. [PMID: 33279682 DOI: 10.1016/j.jgar.2020.11.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 10/23/2020] [Accepted: 11/17/2020] [Indexed: 10/22/2022] Open
Abstract
OBJECTIVES Tuberculosis (TB) is a preventable and treatable infectious disease, but the continuing emergence and spread of multidrug-resistant TB is threatening global TB control efforts. This study aimed to describe the frequency and patterns of drug resistance-conferring mutations of Mycobacterium tuberculosis (MTB) isolates detected from pulmonary TB patients in Tigray Region, Ethiopia. METHODS A cross-sectional study design was employed to collect sputum samples from pulmonary TB patients between July 2018 to August 2019. Culture and identification tests were done at Tigray Health Research Institute (THRI). Mutations conferring rifampicin (RIF), isoniazid (INH) and fluoroquinolone (FQ) resistance were determined in 227 MTB isolates using GenoType MTBDRplus and GenoType MTBDRsl. RESULTS Mutations conferring resistance to RIF, INH and FQs were detected in 40/227 (17.6%), 41/227 (18.1%) and 2/38 (5.3%) MTB isolates, respectively. The majority of mutations for RIF, INH and FQs occurred at codons rpoB S531L (70%), katG S315T (78%) and gyrA D94Y/N (100%), respectively. This study revealed a significant number of unknown mutations in the rpoB, katG and inhA genes. CONCLUSION High rates of mutations conferring resistance to RIF, INH and FQs were observed in this study. A large number of isolates showed unknown mutations, which require further DNA sequencing analysis. Periodic drug resistance surveillance and scaling-up of drug resistance testing facilities are imperative to prevent the transmission of drug-resistant TB in the community.
Collapse
Affiliation(s)
- Letemichael Negash Welekidan
- Department of Para Clinical Sciences, Norwegian University of Life Sciences, P.O. Box 369, 0102 Oslo, Norway; Department of Production Animal Medicine, Norwegian University of Life Sciences, P.O. Box 369, 0102 Oslo, Norway; Department of Medical Microbiology and Immunology, Division of Biomedical Sciences, College of Health Sciences, Mekelle University, P.O. Box 1871, Mekelle, Ethiopia.
| | - Eystein Skjerve
- Department of Production Animal Medicine, Norwegian University of Life Sciences, P.O. Box 369, 0102 Oslo, Norway
| | - Tsehaye Asmelash Dejene
- Department of Medical Microbiology and Immunology, Division of Biomedical Sciences, College of Health Sciences, Mekelle University, P.O. Box 1871, Mekelle, Ethiopia
| | | | - Ola Brynildsrud
- Department of Para Clinical Sciences, Norwegian University of Life Sciences, P.O. Box 369, 0102 Oslo, Norway; Department of Bacteriology and Immunology, Norwegian Institute of Public Health, P.O. Box 222, 0213 Oslo, Norway
| | - Tone Tønjum
- Department of Microbiology, Unit for Genome Dynamics, University of Oslo, P.O. Box 1072, 0316 Oslo, Norway; Department of Microbiology, Unit for Genome Dynamics, Oslo University Hospital, P.O. Box 4950, 0424 Oslo, Norway
| | - Solomon Abebe Yimer
- Department of Microbiology, Unit for Genome Dynamics, Oslo University Hospital, P.O. Box 4950, 0424 Oslo, Norway; Coalition for Epidemic Preparedness Innovations, Oslo, Norway
| |
Collapse
|