Systemic inflammatory response syndrome in adult patients with nosocomial bloodstream infection due to Pseudomonas aeruginosa.

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.