Background:

ESBLs are extremely broad spectrum Beta–Lactamase enzymes found in a variety of Enterobacteriaceae to include Klebsiella pneumoniae, other Klebsiella species and Escherichia coli (E.Coli). These ESBL–producing bacteria are highly effective at inactivating various Beta–Lactam antibiotics, and are often leading to an associated increase in morbidity and mortality. ESBLs are considered an emerging threat and are associated with limited treatment options. Recently, the laboratory in our community hospital reported the prevalence of ESBL E.Coli had reached 15 %. 15 % is often considered a threshold of resistance that mandates changes in practice in treatment of infections. We wondered if physicians have altered their management when ESBLs organisms were identified. OBJECTIVE: The purpose of this study was to evaluate the management of UTI caused by ESBL, to determine if patients with ESBL UTI were treated with appropriate antibiotics and if they were associated with more adverse outcomes. Finally, we attempted to determine if there were patient characteristics that would help predict an increase likelihood of having ESBLs infections.

Methods:

Retrospective chart review of 68 patients aged 18 and older who presented to the ER or were admitted for a UTI from September 2009 to September 2010 with positive cultures for gram–negative rods (GNR) which were later confirmed to be ESBLs producing organisms.

Results:

68 patients with a primary diagnosis of urinary tract infection with GNR confirmed to be ESBLs by the micro lab were included in the study. 63 were E. Coli, 3 K. Pneumoniae, 1 K. Oxytoca and 3 P. Mirabilis. 55%(38) were treated with non–carbapenem antibiotics and of which 10% (7) were switched to a carbapenem during their hospitalization; 35 %( 24) were treated with a carbapenem. About 7 %( 5) developed septic shock and had to be transferred to ICU. The severity of comorbidity Charlson index was 4 or more in 52 %(36), 77 %( 53) were = 60 year old, 26 %( 18) were nursing home residents; 44%(30) had recurrent infections, and nearly 95% had previous exposure to antibiotics.

Conclusions:

Only a minority of patients were treated on admission with antibiotics that had a significant activity against ESBLs. More distressing is that very few patients were ever switched to appropriate treatment. Patients in our study were likely to have high Charlson index or were nursing home residents, had previous admissions and exposure to antibiotics which suggest that those characteristics should be taken in consideration for choosing the initial antibiotics of UTI. Reinforcing infection control, more efforts to increase provider awareness of the high prevalence of ESBL and emphasizing antibiotic stewardship could be the most effective means of controlling and decreasing the spread of ESBLs