Hospital-acquired infective endocarditis: should the definition be broadened?

Hospital-acquired infective endocarditis (IE) is a growing health-care problem. Hospital-acquired IE, according to the commonly used definition, is IE manifesting > or =72 h after admission to the hospital or within several weeks after a hospital-based invasive procedure. To assess the validity of this definition, we evaluated 87 episodes of IE, with special attention to recent hospitalizations. The incidence rate of IE in the 6-month period after discharge from the hospital was 27 cases per 100,000 person-years, compared with 1.1 cases per 100,000 person-years in a population with no recent hospitalizations. Furthermore, episodes of IE manifesting during this 6-month period were notable for a high proportion of typically hospital-acquired pathogens (26% vs. 0%; P=.001) and a low proportion of viridans streptococci (0% vs. 36%; P<.001), compared with community-acquired episodes that did not involve recent hospitalization. We conclude that characteristics of hospital-acquired IE extend to episodes arising within 6 months after discharge from the hospital and suggest that the definition of hospital-acquired IE be broadened to include these episodes.