Spatio-temporal distribution of extended spectrum β-lactamase producing Escherichia coli and Klebsiella pneumoniae blood stream infections in Laos.

Objectives: ESBLs are an important cause of third generation cephalosporin resistance in Enterobacterales. However, there is a paucity of data on ESBLs in blood stream infections (BSI) in Laos. The aim of this study was to investigate the presence of ESBL-producing Escherichia coli (ESBLEC) and ESBL-producing Klebsiella pneumoniae (ESBLKP) in blood cultures submitted to Mahosot Hospital, Laos and how these have changed over 18 years.

Methods and materials: This retrospective observational study included blood cultures from patients presenting with fever to Mahosot Hospital between 2000 and 2018. Full identification and antibiotic susceptibility testing was carried out on positive bottles. ESBL production was determined using the double-disc method. Patient clinical and residence data were included in univariable and multivariable analyses to identify risk factors for having an ESBL.

Results: From 52 249 blood culture sets collected over the 18-year period, 222 (0.42%) were positive for an ESBLEC or ESBLKP. The proportion of E. coli and K. pneumoniae isolates that were ESBL positive increased from 3.2% in 2000 to 35.4% in 2018. While there was a steady increase seen in ESBLEC over the 18-year period, ESBLKP have remained at ∼7% of K. pneumoniae isolates. Most ESBLs were community acquired. From univariable analysis, factors positively associated with an ESBL isolate included chronic renal failure, renal stones and having taken an antibiotic in the week before the blood sample.

Conclusion: With a rising trend of ESBLEC in Laos, controlling unregulated antibiotic usage in the community will be pivotal to stopping further increases.