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. Journal of Hospital Medicine 2014;9:232–238. © 2014 Society of Hospital Medicine