Impact of Extended-spectrum β-lactamase-producing Organisms on Clinical and Economic Outcomes in Patients with Urinary Tract Infection

Objective: To compare clinical and economic outcomes between patients with urinary tract infection (UTI) due to extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella species (ESBL-EK) versus patients with non-ESBL-EK UTI.

Patients And Methods: Eighty-four (3.6%) of 2345 patients admitted between September 1, 2011 and August 31, 2012 with UTI were positive for ESBL-EK. Fifty-five ESBL-EK UTI (cases) and matched controls (non-ESBL-EK UTI) were included in the analysis. Clinical and economic outcomes were compared between cases and controls for statistical significance.

Results: Cases were more likely to have diabetes mellitus, a history of recurrent UTIs, recently received antibiotics, recently been hospitalized, and had previous isolation of an ESBL-producing organism compared with controls. Failure of initial antibiotic regimen (62% vs 6%; P < 0.001) and time to appropriate antibiotic therapy (51 vs 2.5 hours; P < 0.001) were greater in cases. The median cost of care was greater (additional $3658; P = 0.02) and the median length of stay (LOS) prolonged for cases (6 vs 4 days; P = 0.02) despite similar hospital reimbursement (additional $469; P = 0.56). Although not significant, infection-related mortality (7.2% vs 1.8%) and 30-day UTI readmission (7.2% vs 3.6%) were higher in ESBL-EK cases.

Conclusions: UTI caused by ESBL-EK is associated with significant clinical and economic burden. The cost of care and LOS of patients with ESBL-EK UTI were 1.5 times those caused by non-ESBL-EK. Importantly, the additional cost of care is a liability to the hospital, as this is not offset by reimbursement. Appropriate and timely initial antibiotics may minimize the ESBL-EK impact on outcomes of patients with UTI.