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Background: Drug-resistant tuberculosis (DR-TB) poses a major global challenge to public health and therapeutics. It is an emerging global concern associated with increased morbidity and mortality mostly seen in the low- and middle-income countries. Molecular techniques are highly sensitive and offer timely and accurate results for TB drug resistance testing, thereby positively influencing patient management plan., Methods: The study was carried out at the National Tuberculosis Reference Laboratory (NTRL) in Kenya in the period between January and October 2022. A total of 243 Mycobacterium tuberculosis (M.tb) clinical isolates were included in the study. These isolates comprised of 50 isolates with mutations in rpoB, 51 isolates with katG mutations, 51 isolates with mutations in inhA, and 91 M.tb isolates lacking mutations in these genes based on Genotype MTBDRplus results. DNA from the isolates was extracted using the FluoroLyse extraction kit. Real-time polymerase chain reaction targeting the rpoB, InhA, and katG genes was performed using the FluoroType MTBDR amplification mix. Isolates with discordant results between Genotype MTBDRplus and FluoroCycler® MTBDR assays underwent targeted sequencing for the respective genes, then, sequences were analyzed for mutations using Geneious version 11.0 software., Results: The sensitivity of the Fluorocycler XT MTBDR assay for the detection of mutations that confer drug resistance was 86% (95% confidence interval [CI] 73.0-94.0) for rpoB, 96% (95% CI 87-100) for katG and 92% (95% CI 81-98) for inhA. The assay's specificity was 97% (95% CI 93-99) for rpoB, 98% (95% CI 96-100) for katG, and 97% (95% CI 93-99) for inhA., Conclusion: The diagnostic accuracy of FluoroType MTBDR for the detection of mutations conferring resistance to rifampicin and isoniazid was high compared with that of Genotype MTBDRplus and demonstrates its suitability as a replacement assay for Genotype MTBDRplus., (Copyright © 2024 Copyright: © 2024 International Journal of Mycobacteriology.)

Background: Non-Tuberculous Mycobacteria (NTM) transmission to humans occurs through inhalation of dust particles or vaporized water containing NTM leading to pulmonary manifestations. NTM infections are often misdiagnosed for tuberculosis (TB) due to their similar clinical and radiological manifestations., Aims and Objectives: We, therefore, performed a species-level identification of NTM in symptomatic TB negative patients through sequencing of the hsp65 gene., Materials and Methods: We conducted a cross-sectional study at the National Tuberculosis Reference Laboratory in the period between January to November 2020. One hundred and sixty-six mycobacterial culture-positive samples that tested negative for TB using capilia underwent Polymerase Chain Reaction targeting the hsp65 gene. Isolates showing a band with gel electrophoresis at 441 bp position were sequenced using Sanger technology. Geneious software was used to analyze the obtained sequences, and the National Center for Biotechnology Information gene database identified NTM species for each isolate. A phylogenetic tree was constructed from the DNA sequences and evolutionary distances computed using the general time-reversible method. Pearson chi-square was used to determine the association between NTM infection and participants' characteristics., Results: Our study identified 43 different NTM species. The dominant NTM belonged to Mycobacterium avium complex 37 (31%). Slow-growing NTM were the majority at 86 (71%) while rapid-growing NTM were 36 (29%). A significant association (P<0.05) was observed for regions and age, while patient type had a weak likelihood of NTM infection., Conclusion: Our study characterized the diversity of NTM in Kenya for the first time and showed that species belonging to M. Avium Complex are the most prevalent in the country., Competing Interests: None