Mortality risk of bloodstream infection caused by either Escherichia coli or Klebsiella pneumoniae producing extended-spectrum β-lactamase: a prospective cohort study

OBJECTIVE: Several studies reported that infection of extended-spectrum β lactamase (ESBL)-producing Escherichia coli (E. coli) or Klebsiella pneumoniae (K. pneumoniae) contributed to higher mortality rates but others found it was not associated with mortality. A prospective cohort study which involved 72 patients was conducted to assess the risk of mortality of bloodstream infection due to ESBL-producing K. pneumoniae or E. coli as compared to those infected by either K. pneumoniae or E. coli which not produce ESBL. RESULT: Mortality in the group of patients infected with ESBL-producing bacteria was 30.6%, whereas in another group which was infected with non ESBL-producing bacteria was 22.2% (p = 0.59). Kaplan–Meier’s analysis showed that the survival rate during 14-days follow-up among these two group was not significantly different (p = 0.45) with hazard ratio 1.41 (95% CI 0.568–3.51). Stratification analysis found that adult and elderly patients, patients with sign of leukocytosis, and patients treated with carbapenem were modifier effect variables.