Acquisition of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae in intensive care units in Thailand.

This study aimed to assess the prevalence and associated risk factors for extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae (ESBL-EK) acquisition among patients staying in medical and surgical Intensive Care Units (ICU) in Northern Thailand. Rectal swabs were collected from 206 ICU patients upon admission and discharge. Overall, the ESBL-EK acquisition rate among patients during ICU stay was 29.6%. Acquisition rate was significantly higher for K. pneumoniae (20.9%) than that of E. coli (12.1%) (p = 0.024). Multivariate logistic regression analysis identified the use of third generation cephalosporin (p = 0.008) as a risk factor for ESBL-EK acquisition. Sixty-eight ESBL-EK isolates (25 E. coli and 43 K. pneumoniae) were recovered. The majority of ESBL-EK isolates (≥88%) were resistant to ceftazidime, cefepime and aztreonam. Fifty-two acquired ESBL-EK isolates (76.5%) were positive for blaCTX-M and 4 K. pneumoniae isolates simultaneously carried blaNDM-1. Our results reveal that ICU patients could acquire ESBL-EK during hospitalization and the use of third generation cephalosporin should be strictly controlled to prevent the acquisition of ESBL-EK among ICU patients.