Multidrug-resistant (MDR), highly resistant (XDR), and pan-resistant (PDR) bacteria to antimicrobials are a major public health problem worldwide, particularly in America, Africa, Europe, Russia, and Chad, due to their prevalence, impacts, difficulties in therapeutic management, and socio-economic consequences. This was a descriptive, cross-sectional, and etiological diagnostic study conducted from January 17, 2012, to December 7, 2025, at the bacteriology and mycobacteria laboratories of the National Reference Hospital Center (CHURN) of N’Djamena, and at the Bacteriology Unit of the Laboratory for Research, Diagnostic and Scientific Expertise (Labo-ReDES) of the Faculty of Human Health Sciences (FSSH) of the University of N’Djamena, following standard phenotypic and molecular methods of clinical microbiology. The objective of this study was to produce a map of resistance genes of MDR, XDR, and PDR to antimicrobials and healthcare-associated infections from 2012 to 2025 in Chad. In the study, 851 resistant bacterial phenotypes were identified, including 329 MDR bacteria, 407 ESBL, 114 XDR bacteria, and 10 PDR. The emerging resistant bacteria identified were: Staphylococcus aureus (65%), Escherichia coli (90%), Klebsiella pneumoniae (25%), Enterobacter cloacae (8%), Salmonella spp. (18%), Acinetobacter baumannii (2%), and Shigella flexneri (21%). The identified CREs were: Enterococcus (11%) and carbapenemase-producing Enterobacteriaceae (Escherichia coli, Enterobacter, Serratia, etc.). Vibrio cholerae (25%) and Neisseria menigitidis (34%) were also present. The detected resistance genes were those of: Mycobacterium tuberculosis (rpoB, inhA, KatG/inhA, gyrA and gyrB, rrs and eis), Mycobacterium leprae (rpoB, flop1, gyrA and gyrB), and the chloride toxin-producing genes of Vibrio cholerae (ctxA, ctxB, gyrA, gyrB), Staphylococcus and Enterobacteriaceae (E. coli, Klebsiella, Enterobacter, etc.: mecA, ACC (6') and Enterococcus (vanA). The results of this study highlight the importance of mandating adherence to antituberculosis and antileprosy medications for patients, requiring prescribers to prescribe based on laboratory evidence, and ultimately, urging policymakers to organize laboratories in the country’s 23 provinces and equip them with high-performance
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