High prevalence of ESBL-producing Escherichia coli and Klebsiella pneumoniae in community-onset bloodstream infections in China

Objectives: Community-onset bloodstream infections (COBSIs) caused by ESBL-producing Escherichia coli (ESBLEC) and ESBL-producing Klebsiella pneumoniae (ESBL-KP) are increasing globally. This study aimed to investigate the epidemiology and risk factors of ESBL-EC and ESBL-KP in COBSIs in China. Methods: A prospective, multicentre study was performed in 28 tertiary hospitals from September 2013 to November 2014. All isolates and ESBLs were microbiologically characterized. A statistical analysis of risk factors was performed using binary logistic regression. The trial was registered with ClinicalTrials. gov (NCT01961206). Results: A total of 919 consecutive episodes of COBSIs were reported and 640 E. coli and 279 K. pneumoniae isolates (non-duplicate) were collected. According to the criteria, 662 (72.0%) cases were classified as having community-acquired bloodstream infections, while the remaining 257 (28.0%) were classified as having health-care-associated bloodstream infections. The proportions of ESBL producers were 55.5% (355/640) among E. coli isolates and 16.5% (46/279) among K. pneumoniae isolates, respectively. Healthcare-associated infections, obstructive urinary tract disease, previous surgical history and use of a cephalosporin antibiotic within 3 months were independent predictors of COBSIs caused by ESBL-EC. Heart failure was the only independent risk factor for COBSIs due to ESBL-KP. Age was not independently associated with infections caused by ESBL producers. CTX-M14 was the most common ESBL genotype and was widespread throughout the country. Conclusions: ESBL producers are highly prevalent in COBSIs in China, especially among cases caused by E. coli. For these resistant pathogens, clinicians should consider adequate empirical therapy, and different risk factors for prediction should be used in this country.