Deaths attributable to carbapenem-resistant Enterobacteriaceae infections

We evaluated the number of deaths attributable to carbapenem-resistant Enterobacteriaceae by using studies from around the world published before April 9, 2012. Attributable death was defined as the difference in all-cause deaths between patients with carbapenem-resistant infections and those with carbapenem-susceptible infections. Online databases were searched, and data were qualitatively synthesized and pooled in a metaanalysis. Nine studies met inclusion criteria: 6 retrospective case-control studies, 2 retrospective cohort studies, and 1 prospective cohort study. Klebsiella pneumoniae was the causative pathogen in 8 studies; bacteremia was the only infection in 5 studies. We calculated that 26%-44% of deaths in 7 studies were attributable to carbapenem resistance, and in 2 studies, which included bacteremia and other infections, -3% and -4% of deaths were attributable to carbapenem resistance. Pooled outcomes showed that the number of deaths was significantly higher in patients with carbapenem-resistant infections and that the number of deaths attributable to carbapenem resistance is considerable.