ABSTRACT
OBJECTIVES: To determine whether the systemic inflammatory response syndrome (SIRS), clinical course, and outcome of monomicrobial nosocomial bloodstream infection (BSI) due to Pseudomonas aeruginosa or Enterococcus spp. is different in elderly patients than in younger patients. DESIGN: Historical cohort study. SETTING: An 820-bed tertiary care facility. PARTICIPANTS: One hundred twenty-seven adults with P. aeruginosa or enterococcal BSI. MEASUREMENTS: SIRS scores were determined 2 days before the first positive blood culture through 14 days afterwards. Elderly patients (> or =65, n=37) were compared with nonelderly patients (<65, n=90). Variables significant for predicting mortality in univariate analysis were entered into a logistic regression model. RESULTS: No difference in SIRS was detected between the two groups. No significant difference was noted in the incidence of organ failure, 7-day mortality, or overall mortality between the two groups. Univariate analysis revealed that Acute Physiology And Chronic Health Evaluation (APACHE) II score of 15 or greater at BSI onset; adjusted APACHE II score (points for age excluded) of 15 or greater at BSI onset; and respiratory, cardiovascular, renal, hematological, and hepatic failure were predictors of mortality. Age, sex, use of empirical antimicrobial therapy, and infection with imipenem-resistant P. aeruginosa or vancomycin-resistant enterococci did not predict mortality. Multivariate analysis revealed that hematological failure (odds ratio (OR)=8.1, 95% confidence interval (CI)=2.78-23.47), cardiovascular failure (OR=4.7, 95% CI=1.69-13.10), and adjusted APACHE II > or = 15 at BSI onset (OR=3.1, 95% CI=1.12-8.81) independently predicted death. CONCLUSION: Elderly patients did not differ from nonelderly patients with respect to severity of illness before or at the time of BSI. Elderly patients with pseudomonal or enterococcal BSIs did not have a greater mortality than nonelderly patients.
Subject(s)
Bacteremia/complications , Enterococcus , Gram-Positive Bacterial Infections/complications , Pseudomonas Infections/complications , Systemic Inflammatory Response Syndrome/microbiology , Age Factors , Aged , Bacteremia/mortality , Bacteremia/therapy , Critical Care , Female , Gram-Positive Bacterial Infections/mortality , Gram-Positive Bacterial Infections/therapy , Hospital Mortality , Humans , Length of Stay , Male , Middle Aged , Outcome Assessment, Health Care , Pseudomonas Infections/mortality , Pseudomonas Infections/therapy , Systemic Inflammatory Response Syndrome/mortality , Systemic Inflammatory Response Syndrome/therapyABSTRACT
OBJECTIVES: To evaluate relationships between the inflammatory response, clinical course, and outcome of nosocomial BSI due to Pseudomonas aeruginosa. METHODS: We performed a historical cohort study on 77 adults with P. aeruginosa (Pa) nBSI to define the associated systemic inflammatory response syndrome (SIRS). We examined SIRS scores 2 days prior through 14 days after the first positive blood culture. Imipenem resistant--IRPa (n=20) and susceptible infections--ISPa (n=57) were compared. Variables significant in univariate analysis were entered into a logistic regression model. RESULTS: Seventy-four percent of BSI were ISPa and 26.0% by IRPa. Septic shock occurred in 39.0%. Crude mortality was 48.1%. There was no difference in APACHE II (AP2) scores on days -2, -1 and 0 between the ISPa and IRPa groups. Multivariate analysis revealed that AP2> or =20 at BSI onset (P<0.001) and hematologic failure (P=0.001) independently predicted death. CONCLUSIONS: In patients with P. aeruginosa nBSI, the incidence of septic shock and organ failure is high; patients with IRPa BSI are not more acutely ill prior to infection than those with ISPa BSI and outcome is not significantly different; AP2> or =20 at BSI onset and the development of hematologic failure are independent predictors of death.