Extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiellapneumoniae: Risk factors for infection and impact of resistance on outcomes

The prevalence of antibiotic resistance among extended-spectrum beta -lacta mase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae has increa sed markedly in recent years. Thirty-three patients with infection due to E SBL-producing E. coli or K. pneumoniae (case patients) were compared with 6 6 matched controls. Total prior antibiotic use was the only independent ris k factor for ESBL-producing E, coli or K. pneumoniae infection (odds ratio, 1.10; 95% confidence interval, 1.03-1.18; P = .006). Case patients were tr eated with an effective antibiotic a median of 72 hours after infection was suspected, compared with a median of 11.5 hours after infection was suspec ted for controls (P < .001). ESBL-producing E. coli or K, pneumoniae infect ion was associated with a significantly longer duration of hospital stay an d greater hospital charges (P = .01 and P < .001, respectively). Finally, m any ESBL-producing E. coli and K, pneumoniae isolates were closely related. ESBL-producing E. coli and K. pneumoniae infections have a significant imp act on several important clinical outcomes, and efforts to control outbreak s of infection with ESBL-producing E. coli and K. pneumoniae should emphasi ze judicious use of all antibiotics as well as barrier precautions to reduc e spread.