Microbial etiology and antimicrobial resistance in healthcare-associated versus community-acquired and hospital-acquired bloodstream infection in a tertiary care hospital.

Infections that occur in patients with significant exposure to the nosocomial environment while they reside in the community are currently classified separately as healthcare-associated infections. In this retrospective study, conducted at Ghent University Hospital between January 1, 2009, and May 31, 2011, we compared microbial characteristics of healthcare-associated bloodstream infection (HCAB) with that of community-acquired bloodstream infection (CAB) and hospital-acquired bloodstream infection (HAB). Three hundred eighty-six pathogens isolated from patients with HCAB were compared with 141 and 605 pathogens identified in patients with CAB and HAB, respectively. HCAB was associated with a distinct pathogen profile and with an antimicrobial susceptibility pattern different from that of other categories of bloodstream infection. We conclude that the concept of HCAB provides guidance in the choice of empirical antibiotic therapy but should be translated according to local epidemiology.