Case-control study of risk factors for the development of enterococcal bacteremia

To determine the risk factors involved in the development of enterococcal b acteremia, a prospective, observational, case-control study was carried out over 18 months. All episodes of enterococcal bacteremia with clinical sign ificance detected in adults were included. A control matched by sex, age an d hospitalization ward (medical, surgical or intensive care unit) was selec ted randomly for each patient with enterococcal bacteremia. Uni- and multiv ariate analyses of the epidemiological characteristics of both groups were performed. Etiologic fractions of every risk factor were also determined. O ne hundred twenty-two pairs were included. The severity of the chronic unde rlying diseases was similar in both groups. Neutropenia, cirrhosis, organ t ransplantation, intravascular catheter, urinary catheter, nasogastric tube, parenteral nutrition and previous administration of cephalosporins and imi penem were the factors associated with enterococcal bacteremia in the univa riate analysis. The factors independently associated with enterococcal bact eremia in the multivariate analysis were neutropenia (odds ratio [OR] = 8), urinary catheter (OR = 3) and previous administration of cephalosporins (O R = 4) and imipenem (OR = 10). Their respective etiologic fractions were 9% , 44%, 11% and 29%. Efforts to reduce the occurrence of enterococcal bacter emia should be focused on appropriate use of cephalosporins, imipenem and e xternal devices.