[Bacteremia in patients undergoing chronic hemodialysis in a 16-year period]. / Análisis de la bacteriemia en pacientes sometidos a hemodiálisis crónica en un período de 16 años.

OBJECTIVE: To determine the incidence of bacteremia among patients on hemodialysis, the responsible microorganisms and to describe the predisposing and prognostic factors. METHODS: A retrospective analysis was conducted of 85 episodes of bacteremia occurred from 1979-1994; the episodes involved 71 patients (male/female ratio: 27/44) with a mean age of 58 years (29-80). RESULTS: Eighty-seven microorganisms were recovered, which included 61 grampositive cocci (67% Staphylococcus aureus), 25 gramnegative bacilli (52% Escherichia coli) and 1 anaerobe. The mean incidence was 3.1/100 patients on hemodialysis/year (range: 1.1-8.3), higher in patients with interstitial and cystic renal disease. In 52% of cases an intravascular source was detected, associated with vein access for hemodialysis (in 91% there were inflammatory signs at the fistula). In 16 cases (19%) no portal of entry was detected and in the remaining patients the portal of entry had an extravascular origin. Eighty patients received antibiotic therapy and 35 patients required the substitution of the vein access. Thirteen patients died (15%) as a result of bacteremia. The mortality rate was higher among patients developing shock (50%), endocarditis (75%) and in those who had remained for longer than 1,000 days on hemodialysis (45%). Bacteremia accounted for the third known cause of death on dialysis, and was responsible for 11% of deaths occurred during the time of the study. CONCLUSIONS: Bacteremia among hemodialysed patients was mainly associated with Staphylococcus aureus infections at the vascular access. Bacteremia was the direct responsible for 11% of deaths occurred on dialysis.

Nosocomial outbreak caused by Scedosporium prolificans (inflatum): four fatal cases in leukemic patients.

Four cases of fatal disseminated Scedosporium prolificans (inflatum) infection occurring in neutropenic patients are reported. Because of hospital renovation, the patients were cared for in a temporary hematologic facility. S. prolificans (inflatum) was isolated from blood cultures of these four patients, two of whom underwent full necropsy, and revealed abundant vegetative hyphae and ovoid conida with truncate bases in many organs. In vitro susceptibility testing of fungal strains showed all isolates to be resistant to amphotericin B, flucytosine, miconazole, ketoconazole, fluconazole, and itraconazole, with MICs greater than 16 micrograms/ml. The reported infections, two in each of two rooms, occurred over a period of 1 month, with very similar clinical outcomes. Circumstancial evidence suggested a nosocomial outbreak, but the environmental samples collected from the rooms, corridors, and adjacent areas did not yield S. prolificans (inflatum). Nevertheless, circumstantial evidence suggested a nosocomial outbreak of S. prolificans (inflatum) infection.

[Hospital infection caused by enterococci. The previous use of antibiotics as risk factors in a case-control study]. / Infección hospitalaria por enterococos. El uso previo de antibióticos como factor de riesgo a través de un estudio de casos y controles.

BACKGROUND: Nosocomial infection by enterococci is of growing importance and recognition. The risk factors, morbidity and prognosis of the same were investigated by a case and control study in a third level university hospital. METHODS: One hundred patients with nosocomial infection by enterococci were compared with 100 randomly selected control patients with non enterococcic nosocomial infection. Cases and controls were taken from a series of 10,926 patients examined in search of nosocomial infection by successive cut offs of prevalence. RESULTS: The prevalence of nosocomial infection by enterococci was found to be 9.9 per 1,000 admissions. Analysis among cases and controls by the odds ratio indicated a positive association for nosocomial infection by enterococci for the following risk factors: male sex (1.8), receipt of intensive care (3.6), predisposing diseases (3.1), urinary catheter (3), abdominal-genital surgery (2.4) or nephro-urologic surgery (4.6), other previous infections (1.9) and previous exposure to antibiotics (3.7), mainly aminoglucosides (4.2). Urinary infections and those of the surgical wound predominated, 15 patients had bacteremia, with mortality related with infection being 2%, preinfection hospital stay was 34.7 days and the mean stay was of 8.3 days but these data were not statistically different in the control group. The enterococcic infections were most frequently polymicrobian (odds ratio 5.5) received worse antibiotic coverage (5.1) and presented greater number of therapeutic failures or recurrences (2.5). CONCLUSIONS: Nosocomial infection by enterococci is relatively frequent and virulent. The risk factors identified in this study are in agreement with those found in most series. The previous use of aminoglucosides was specially capable of selecting enterococci but only 13% demonstrated high level resistance to gentamicin.