Surveillance of extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae at a comprehensive cancer center in Japan, 2009-2013.

We examined the results of surveillance of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae, which are pathogens known to cause nosocomial outbreaks, at a comprehensive cancer center in Japan over a 5-year period. We found that the admission prevalence and the incidence of ESBL-producing E coli increased during the study period, in contrast with ESBL-producing K pneumoniae, in which the parameters remained low throughout the study period.