Genotypic and phenotypic profiles of antibiotic-resistant bacteria isolated from hospitalized patients in Bangladesh

Trop Med Int Health. 2021 Apr 10. doi: 10.1111/tmi.13584. Online ahead of print.


OBJECTIVES: Characterization of resistance phenotype and genotype is crucial to understanding the burden and transmission of antimicrobial-resistance (AMR). This study aims to determine the spectrum of AMR and associated genes encoding aminoglycoside, macrolide and β-lactam classes of antimicrobials in bacteria isolated from hospitalized patients in Bangladesh.

METHODS: 430 bacterial isolates from patients with respiratory, intestinal, wound infections, and typhoid fever, presenting to clinical care from 2015-2019, were examined. They included Escherichia coli (n= 85); Staphylococcus aureus (n= 84); Salmonella typhi (n= 82); Klebsiella pneumoniae (n= 42); Streptococcus pneumoniae (n= 36); coagulase-negative staphylococci (n= 28); Enterococcus faecalis (n= 27); Pseudomonas aeruginosa (n= 26) and Acinetobacter baumannii (n= 20). Reconfirmation of these clinical isolates and antimicrobial susceptibility tests was performed. PCR amplification using resistance gene-specific primers was done and the amplified products were confirmed by Sanger sequencing.

RESULTS: 53% of isolates were multidrug-resistant (MDR), including 97% of Escherichia coli. There was a year-wise gradual increase of MDR isolates from 2015-2018 and there was an almost 2-fold increase in the number of MDR strains isolated in 2019 (P= 0.00058). Among the 5 extended spectrum β-lactamases investigated, CTX-M-1 was the most prevalent (63%) followed by NDM-1 (22%); Escherichia coli was the major reservoir of these genes. The ermB (55%) and aac(6')-Ib (35%) genes were the most frequently detected macrolide and aminoglycoside resistance genes, respectively.

CONCLUSION: MDR pathogens are highly prevalent in hospital settings of Bangladesh.

PMID:33838068 | DOI:10.1111/tmi.13584