Characteristics of Klebsiella pneumoniae Bacteremia in Community-acquired and Nosocomial Infections in Diabetic Patients

Background: Although diabetes mellitus is known as a major risk factor for Klebsiellapneumoniae infection, the differences in clinical characteristics betweencommunity-acquired and nosocomial K. pneumoniae bacteremia in diabeticpatients have been rarely reported.Methods: This retrospective analysis enrolled 193 adult diabetic patients with K. pneumoniaebacteremia hospitalized between January 2005 and December 2006.The chi-squared test, analysis of variance (ANOVA), Student’s t test, Fisherexact test, and Cox regression model were used for statistical analysis.Results: Of the enrolled patients, 147 had community-acquired infections and 46 hadnosocomial infections. Compared with the community group, the nosocomialgroup had higher rates of in-hospital mortality (41.3% vs. 18.4%, p = 0.001),malignancy (50.0% vs. 19.0%, p < 0.001), and leukopenia (21.7% vs. 5.4%,p = 0.001) but had lower levels of serum C-reactive protein (124.3 mg/L vs.188.7 mg/L, p = 0.018) and HbA1c (8.1% vs. 9.5%, p = 0.025). The rate ofinfection with the extended-spectrum β-lactamase-producing strain (ESBLinfection) in the nosocomial group was 11 times higher than that in the communitygroup (45.7% vs. 4.1%, p < 0.001). ESBL infection accounted for53% of mortality in the nosocomial group. Pneumonia was more common inthe nosocomial group, while local abscess was more common in the communitygroup. The risk factors for mortality were pneumonia, leukopenia, cirrhosis,and a high serum creatinine ratio (creatinine level at admission/baseline).Conclusions: The nosocomial group had more ESBL infections which might account forthe higher mortality. The HbA1c level during the course of infection did notaffect the outcome. Pneumonia, leukopenia, cirrhosis, and a high serum creatinineratio at admission were the risk factors for poor outcome.