Retrospective analysis of bacteremia because of Enterobacter cloacae compared with Escherichia coli bacteremia

A total of 52 patients of Enterobacter cloacae bacteremia from a University hospital during the period from January 2000 to June 2005 were analysed and compared with a reference group comprising 52 patients of Escherichia coli bacteremia. Overall, E. cloacae ranked the tenth in all pathogens of bacteremia accounting for 2.8% of the total patients. Although the incidence of E. cloacae bacteremia was low, the attributable mortality rate till achieved 13.5%. Most patients (86.5%) with E. cloacae bacteremia were hospital-acquired. The overwhelming majority of patients (92.3%) were men, while almost half of the patients (48.1%) were from the Department of Urological Surgery with underlying diseases such as urinal obstruction, kidney transplantation and kidney tumours. Possible risks factors associated with E. cloacae bacteremia included immunocompromised status, long-term hospitalisation and invasive procedures or surgeries. E. cloacae bacteremia significantly differed from E. coli bacteremia in a number of clinical aspects, including underlying diseases, portal of entry, infection type, risks factors, laboratory findings and appropriateness of empirical antibiotic therapy. Besides the high prevalence of resistance to cephalosporins, most E. cloacae blood isolates were also resistant to ciprofloxacin (resistance rate, 67.3%), gentamicin (73.1%) and tobramycin (73.1%). Based on the findings of the present study, E. cloacae is probably an important pathogen of bacteremia occurring in male patients with underlying urinal system illnesses.