RESUMEN
BACKGROUND: Antimicrobial resistance (AMR) surveillance in low- and middle-income countries (LMICs) often relies on poorly resourced laboratory processes. Centralized sequencing was combined with cloud-based, open-source bioinformatics solutions for national AMR surveillance in Cambodia. METHODS: Blood cultures growing gram-negative bacteria were collected at six Cambodian hospitals (January 2021 - October 2022). Isolates were obtained from pure plate growth and shotgun DNA sequencing performed in-country. Using public nucleotide and protein databases, reads were aligned for pathogen identification and AMR gene characterization. Multilocus sequence typing was performed on whole genome assemblies and haplotype clusters compared against published genomes. FINDINGS: Genes associated with acquired resistance to fluoroquinolones were identified in 59%, TMP/SMX in 45%, and aminoglycosides in 52% of 715 isolates. Extended-spectrum beta-lactamase encoding genes were identified in 34% isolates, most commonly blaCTX-M-15, blaCTX-M-27, and blaCTX-M-55 in E. coli sequence types 131 and 1193. Carbapenemase genes were identified in 12% isolates, most commonly blaOXA-23, blaNDM-1, blaOXA-58 and blaOXA-66 in Acinetobacter species. Phylogenetic analysis revealed clonal strains of A. baumannii, representing suspected nosocomial outbreaks, and genetic clusters of quinolone-resistant typhoidal Salmonella and ESBL E. coli cases suggesting community transmission. INTERPRETATION: With accessible sequencing platforms and bioinformatics solutions, bacterial genomics can supplement AMR surveillance in LMICs. FUNDING: Research was supported by the National Institute of Allergy and Infectious Diseases and the Bill and Melinda Gates Foundation [OPP1211806].
