Etiology of bacteremia.

Blood-culture results for a 15-year period from a large southern hospital were tabulated and analyzed for alterations in the bacterial species associated with bacteremia. From 15,543 cultures, 2,410 positive cultures (15.6%) were obtained. These results were grouped into 5-year periods, and an alteration in the incidence of the agents was demonstrated. In the past 5 years, gram-negative bacilli have replaced gram-positive cocci as the most common agents of bacteremia, and several species not formerly associated with septicemia were found to be involved in a large number of cases. The importance of the clinical laboratory monitoring blood culture results was demonstrated as was the need for constant collaboration between the clinician and microbiologist.