ABSTRACT
Objective: Infection by extended spectrum beta-lactamase (ESBL) producing strains of Escherichia coli and Klebsiella spp. is variably associated with presence of co-morbid conditions, predisposing factors and poor outcome. Objective of this study was to determine the prevalence of ESBL producing strains along with the outcome and risk factors in patients infected with such strains. Materials and Methods: This observational study was conducted on 6910 clinical samples. E coli & Klebsiella spp. were identified with detection of ESBL production according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Patients’ clinical and demographic details along with risk factors and co-morbid conditions, type of response to antimicrobial therapy, length of hospital stay and mortality were collected. Results: 69.62% out of 563 E.coli and 62.80% out of 342 Klebsiella spp. were isolated from 6910 samples were ESBL producers respectively. Male:Female ratio was 1.36:1 and 2.37:1 for E coli and Klebsiella spp. respectively. Blood Stream Infection (p=.006), soft tissue infections (p=0.08), genital tract infections (p=0.03) and admission in intensive care units were significantly associated with risk of infection by Klebsiella spp. Immunosuppressive therapy (p=0.02) and diabetes mellitus (p=0.04) were significant comorbid conditions in ESBL producing E coli infections. The mean duration of hospital stay for ESBL producing E coli and Klebsiella spp. was 13.65 ± 12.6 and 17.89 ± 14.76 days with mortality of 8.6% and 13.34% respectively. Conclusions: Several co-morbid conditions and invasive devices were significantly associated with infection by ESBL-producing, strains of E. coli and Klebsiella spp. with longer duration of hospital stay and increased mortality in comparison to ESBL non-producers.