Genomic characterization of high-risk Escherichia coli and Enterobacter hormaechei clones recovered from a single tertiary-care hospital in Pakistan.

Aims: Spread of carbapenem-resistant Enterobacterales have become a global problem. We characterized extended-spectrum β-lactamase (ESBL)-producing Enterobacterales from urinary tract infections cases from Allied Hospital Faisalabad, Pakistan.

Methods And Results: Eleven (22%, 11/50) ESBL-producing Enterobacterales (Escherichia coli; n = 10 and Enterobacter hormaechei; n = 1) were recovered and processed through VITEK-2, PCR, rep-PCR followed by whole-genome sequencing (WGS) of ESBL-producing Ent. hormaechei and carbapenem-resistant E. coli isolates. Plasmid transferability of bla -producers was assayed by conjugation experiments. All ESBL strains carried the bla gene. Of these bla producing E. coli, four also carried bla located on transferable plasmids. All E. coli strains belonged to ST448 and displayed similar genetic features including genes for antimicrobial resistance, heavy metal, biocides and virulence. Genomic features of a multidrug-resistant (MDR) Ent. hormaechei were also reported for the first time in Pakistan.

Conclusion: Our findings indicate that bla producing E. coli ST448 is a multidrug, heavy metals and biocides-resistant strain. Therefore, the screening of these isolates may be effective in limiting the MDR bacteria spread in hospitalized patients and within the community.

Significance And Impact Of This Study: Spread of multi-drug-resistant ESBL-producing bacteria in the clinical settings of Pakistan is a serious challenge and further limiting treatment options in the country. WGS could be used as a tool in the nationwide antibiotic surveillance programme to explore insights of spread and outbreak.