[Bacteremia in 2 hospitals in Rosario, Argentina].

Bacteremia is associated with high morbidity and mortality. Nosocomial bacteremia is associated with an attributable mortality of 35%. In order to characterize the etiological agent of bacteremia cases during two time periods, 6605 patients were studied as follows: 1) from 1980 to 1982 (n = 2401) and 2) from 1988 to 2000 (n = 4204). A total of 596 cases of bacteremia were detected. The most frequent agents were Staphylococcus aureus, negative coagulase (CNS) Staphylococcus, Klebsiella pneumoniae and Escherichia coli. In the second period, an increase in the frequency of bacteremia caused by gram positive bacteria, particularly gram-positive cocci, was noted. Conversely, gram negative bacteria diminished significantly in the second period, specially enterobacterial species. Methicillin-resistant S. aureus and CNS were significantly more frequently isolated in the second period. Infrequent agents of endocarditis, such as Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, and Corynebacterium urealyticum, were isolated.