Characterization of Drug Resistance Mutations in Mycobacterium tuberculosis Isolates from Moroccan Patients Using...

Area of Science:

• Microbiology
• Genomics
• Public Health

Background:

• Tuberculosis (TB) poses a significant global health challenge, exacerbated by rising drug-resistant Mycobacterium tuberculosis (MTB) strains.
• Morocco faces a growing burden of drug-resistant TB, necessitating advanced diagnostic and surveillance methods.

Purpose of the Study:

• To conduct the first nationwide molecular characterization of MTB clinical isolates in Morocco.
• To utilize the Deeplex-MycTB targeted next-generation sequencing (tNGS) assay for resistance mutation detection and phylogenetic analysis.

Main Methods:

• Analysis of 71 culture-derived DNA samples from Moroccan TB patients.
• Detection of resistance-associated mutations in 18 genes using Deeplex-MycTB tNGS.
• Determination of MTB phylogenetic lineages.

Main Results:

• 75% of 68 interpretable samples showed mutations linked to drug resistance.
• 78% of resistant isolates were multidrug-resistant TB (MDR-TB), with 25.5% classified as pre-extensively drug-resistant TB (pre-XDR-TB).
• Predominant mutations were in rpoB, katG, inhA, and pncA, associated with resistance to first-line drugs; Lineage 4.3 (Euro-American) was prevalent.

Conclusions:

• Targeted next-generation sequencing (tNGS) is effective for rapid detection of drug resistance and molecular surveillance of TB in Morocco.
• Findings support the use of tNGS for guiding individualized TB treatment and informing national control strategies.
• The study provides crucial data on drug resistance patterns and phylogenetic diversity of MTB in Morocco.