Showing 2 results for Madadi-Goli
Nahid Madadi-Goli, Kamal Ahmadi, Sharareh Khanipour, Shahin Pourazar Dizaji, Mahshid Nasehi, Seyed Davar Siadat, Farzam Vaziri, Abolfazl Fateh,
Volume 11, Issue 4 (12-2023)
Abstract
Introduction: Tuberculosis (TB) caused by the bacterium Mycobacterium tuberculosis remains a critical global public health concern due to the high morbidity and mortality rates. Mutation in atpE and Rv0678 genes contributes to drug resistance in M. tuberculosis. This study investigates the antibiotic resistance patterns and mutations in atpE and Rv0678 genes in 22 M. tuberculosis clinical isolates. Methods: Drug susceptibility testing (DST) for rifampin, isoniazid, streptomycin, capreomycin, ofloxacin, kanamycin, and ethambutol was conducted using the proportional method. This was followed by determining the minimum inhibitory concentration (MIC) for bedaquiline (BDQ) via the microplate Alamar blue assay (MABA). Genomic regions encompassing atpE and Rv0678 genes were amplified and sequenced for mutation analysis. Data analysis was performed using SPSS software to interpret mutation patterns concerning drug susceptibility profiles. Results: Of 22 isolates, 5 (27.8%) were extensively drug-resistant tuberculosis (XDR-TB), and 13 (72.2%) were multi-drug resistant tuberculosis (MDR-TB). Resistance rates to kanamycin, ofloxacin, capreomycin, and streptomycin were 40.6%, 46.3%, 85%, and 74.6%, respectively. Additionally, phenotypic resistance to bedaquiline was observed in 12 (54.5%) isolates. Sequencing revealed no resistance-conferring mutations in the atpE or Rv0678 genes among the isolates. Conclusion: Our findings showed substantial resistance to first- and second-line drugs in M. tuberculosis clinical isolates. This highlights the necessity for ongoing, comprehensive studies to elucidate the evolving drug resistance patterns and understand the underlying mechanisms in clinical isolates.
Kamal Ahmadi, Nahid Madadi-Goli, Morteza Masoumi, Mahshid Nasehi, Seyed Davar Siadat, Farzam Vaziri, Abolfazl Fateh,
Volume 11, Issue 4 (12-2023)
Abstract
Introduction: Tuberculosis, caused by Mycobacterium tuberculosis, is one of the most common infectious diseases worldwide. Epidemiological studies of M. tuberculosis drug resistance are critical for improving patient treatment approaches and controlling the spread of tuberculosis. The present study aimed to determine antibiotic resistance among M. tuberculosis clinical isolates using the Microplate Alamar Blue Assay (MABA). Methods: In this descriptive cross-sectional study, 25 M. tuberculosis isolates from clinical samples were identified and confirmed using standard microbiological and biochemical tests. Then, the MIC for the antibiotics Bedaquiline, isoniazid, rifampin, ethambutol, ofloxacin, moxifloxacin, capreomycin, and streptomycin was determined using the MABA method. The results were analyzed using SPSS version 16 software. Results: Among the 25 investigated isolates, the frequencies for MDR, Pre-XDR, and XDR isolates were 20%, 8%, and 32%, respectively. The highest rate of drug resistance was to isoniazid (80%), rifampicin, and ethambutol (76%), and the highest rate of sensitivity was to moxifloxacin (68%). The frequency of isoniazid mono-resistance and rifampicin mono-resistance was 5 cases (50%) and 4 cases (40%), respectively. Conclusion: Our study revealed an alarming rate of MDR and XDR M. tuberculosis strains, indicating that current first-line treatments may be ineffective for a significant number of patients. The bedaquiline resistance among the isolates with no history of previous exposure to this drug suggests unexplored resistance mechanisms. Molecular techniques to accurately identify these mechanisms may contribute to developing more effective treatment strategies to combat drug-resistant tuberculosis.
