Risk factors for bloodstream infection with Klebsiella pneumoniae producing VIM-1 metallo-b-lactamase

Objectives To identify risk factors for bloodstream infections (BSIs) caused by VIM-1-producing Klebsiella pneumoniae (VPKP). Methods Consecutive patients with K. pneumoniae BSIs were identified in three tertiary care hospitals between February 2004 and March 2006. Patients infected with VPKP were designated as cases and those infected with non-VPKP as controls. Potential risk factors for VPKP BSIs were examined by univariate and multivariate analysis. Results A total of 178 patients with K. pneumoniae BSIs were identified; 67 (37.6%) were infected with VPKP (cases) and 111 with non-VPKP (controls). In multivariate analysis, cases were more likely to have been in an intensive care unit (ICU) [odds ratio (OR), 6.78; 95% confidence interval (CI), 2.69-17.06; P3 different classes of antibiotics (OR, 12.6; 95% CI, 2.17-73.27; P=0.01) and have had prior use of carbapenems (OR, 2.83; 95% CI, 1.07-7.49; P=0.03). Conclusions Stay in an ICU, prior use of carbapenems and prior exposure to >3 different classes of antibiotics were independent predictors for VPKP BSIs. These findings provide guidance for antibiotic policies and infection control strategies to contain the spread of VPKP.