Cefepime resistance and associated risk factors among Escherichia coli strains isolated from clinical specimens.

Cefepime is active against bacteria producing chromosomally and plasmid-mediated extended broad-spectrum β-lactamase enzymes. The aim of this study was to evaluate risk factors for acquisition of cefepime resistance in Escherichia coli strains among hospitalized patients in a university hospital in Sanandaj, Iran. The study was a case-control investigation. A case patient was defined as a patient who had one isolate of a cefepime-resistant E. coli strain. A control patient was defined as a patient who had one isolate of a cefepime-sensitive E. coli strain. Cefepime resistance was determined by HiComb MIC tests (HIMEDIA, India). Out of the 255 total isolates, 73 (28.6%) were resistant to cefepime. The previous treatment of cefepime was a risk factor for acquisition of a cefepime-resistant isolate (OR = 6.32, 95% CI: 1.5-25.19, p < 0.007). The use of a ventilator was considered to be a risk for acquisition of a cefepime-resistant isolate (OR = 6.25, 95% CI: 1.86-21.02, p <0.002). The use of a catheter was also found to be a risk factor for acquisition of cefepime resistance (OR = 6.28, 95% CI: 1.86-21.02, p <0.001). There was a significant correlation between days of stay in hospital wards and cefepime resistance (p < 0.003). The main risk factors associated with cefepime resistance were previous treatment with cefepime, use of ventilator, use of catheter and days of stay in ward. More studies are needed to evaluate the role of these factors in order to control the spread of drug resistance.