OBJECTIVE: To determine risk factors for death among patients with nosocomial pneumonia and patients with primary bloodstream infections (BSI) in intensive care units (ICUs). DESIGN: Prospective cohort study. SETTING: Data collected from January 1997 through June 2003 from ICUs registered with the Krankenhaus Infektions Surveillance System in Germany. PATIENTS: A total of 8,432 patients with nosocomial pneumonia from 202 ICUs and 2,759 patients with nosocomial primary BSI from 190 ICUs. METHODS: The following risk factors were considered in the analysis: age, sex, time in the ICU before onset of infection, type of ICU, type and size of hospital, intubation, central venous catheter use, total parenteral nutrition, and type of pathogen. RESULTS: A total of 750 patients (8.9\%) with nosocomial pneumonia and 302 patients (10.9\%) with nosocomial primary BSI died. Multiple logistic regression analysis identified treatment in a medical or surgical ICU (odds ratio OR, 1.55 95\% confidence interval CI, 1.32-1.82) or a hospital with more than 1,000 beds (OR, 2.14 95\% CI, 1.81-2.56), age older than 65 years (OR, 1.54 95\% CI, 1.31-1.81), and infection with methicillin-resistant Staphylococcus aureus (OR, 2.39 95\% CI, 1.81-3.12) or multidrug-resistant Pseudomonas aeruginosa (OR, 3.00 95\% CI, 1.90-4.63) as independent determinants of death from nosocomial pneumonia. Age older than the median of 63 years (OR, 1.44 95\% CI, 1.12-1.86) and methicillin-resistant S. aureus as the causative agent (OR, 2.98 95\% CI, 1.81-5.82) were both associated with increased mortality from primary BSI. The types of infecting pathogens, particularly those resistant to multiple drugs, were also strong outcome predictors among ICU patients. CONCLUSIONS: The study results underline the need for further investigations of the role of antimicrobial resistance in the outcome of patients with nosocomial pneumonia and patients with primary BSI.