Community-onset Bloodstream Infections Caused By ESBLs-producing E.Coil And K.Pneumoniae In China:Epidemiology And Risk Factors In China:Epidemiology And Risk Factors

Objective:Community-onset bloodstream infections (COBSIs) caused by extended-spectrum β-lactamases (ESBLs)-producing Escherichia coli and Klebsiella pneumoniae have recently been increasing worldwide. Initial treatment with inappropriate antibiotics usually causes treatment failure and is associated with higher mortality and increased hospitalization costs. However, in China, reports about the epidemiology and risk factors of COBSIs caused by ESBLs-producing E. coli (ESBL-EC) and K. pneumoniae (ESBL-KP) are lacking currently. This study firstly investigated the epidemiology and risk factors of ESBLs-producing Escherichia coli and K. pneumoniae in China and to provide scientific basis for the rational use of antibacterial agents.Methods:A prospective, observational, multicenter case-control study was performed during September 2013 to November 2014. E. coli and K. pneumoniae causing community-onset bloodstream infections and related clinical data were collected from twenty-eight hospitals of twenty-two provinces and municipalities. The double disk diffusion method was used to confirm the production of ESBLs. Polymerase chain reaction (PCR) and sequencing were applied to screen the bacteria for genes encoding ESBLs. A statistical analysis of risk factors was performed using binary logistic regression.Results:A total of 1023 consecutive, non-duplicate episodes of COBSIs caused by E. coli or K. pneumoniae were collected during the study period, among which 919 episodes were included in the study. Among 640 E. coli isolates,355 (55.5%) produced ESBLs. In contrast, only 46 (16.5%) of 279 K. pneumoniae isolates produced ESBLs. Obstructive urinary tract disease (OR:2.046,95%CI:1.218-3.437, P=0.007), previous surgical history (OR:1.833,95%CI:1.033-3.250, P=0.038), and use of a cephalosporin antibiotic within 3 months (OR:3.440,95%CI:1.680-7.043, P=0.001) were independent predictors of COBSIs caused by ESBL-EC. Heart failure (OR:8.914, 95%CI:1.547-51.369, P=0.014) was the only independent risk factor for COBSIs caused by ESBL-KP. CTX-M-14 was the most common ESBLs genotype and was widespread throughout the country, accounting for 42.4%(170/401) of all isolates. Up to 49.9%(200/401) of patients with ESBLs-associated COBAIs received inappropriate initial therapy.Conclusion:ESBLs-producing bacteria, especially ESBLs-producing E. coli, are highly prevalent in COBSIs in China. Almost half of COBSIs patients received inappropriate initial therapy. This implies that a significant change in the empirical use of antibiotics for certain infections is necessary.