Presence and characterization of bla-positive carbapenemase-producing Klebsiella pneumoniae from outpatients in Thailand.

BACKGROUND

Presently, community-associated carbapenemase-producing Enterobacterales (CPE) remains largely unknown and require public attention. This study aimed to investigate the presence of CPE from outpatients in Thailand.

METHODS

Non-duplicate stool (n = 886) and urine (n = 289) samples were collected from outpatients with diarrhea and urinary tract infection, respectively. Demographic data and characteristics of patients were collected. Isolation of CPE was performed by plating enrichment culture on agar supplemented with meropenem. Carbapenemase genes were screened by PCR and sequencing. CPE isolates were phenotypically and genotypically characterized.

RESULTS

Fifteen samples (1.3%, 14 stool and 1 urine) yielded bla-positive carbapenemase-producing Klebsiella pneumoniae (CPKP). Additional resistance to colistin and tigecycline was observed in 53.3% and 46.7% of isolates, respectively. Age >60 years was identified as a risk factor for patients with CPKP (P < 0.001, adjusted odds ratio = 11.500, 95% confidence interval = 3.223-41.034). Pulsed field gel electrophoresis revealed genetic diversity of CPKP isolates; however, clonal spread has been observed. ST70 (n = 4) was common, followed by ST147 (n = 3). bla from all isolates were transferable and mainly resided on IncA/C plasmid (80%). All bla plasmids remained stable in bacterial host for at least 10 days in antibiotic-free environments, regardless of replicon types.

CONCLUSION

This study demonstrates that the prevalence of CPE among outpatients in Thailand remains low and the spread of bla-positive CPKP may be driven by IncA/C plasmid. Our results emphasize the need for a large-scale surveillance study to limit further spread of CPE in community.