Factors associated with 12 week case-fatality in Staphylococcus aureus bacteraemia: a prospective cohort study

Area of Science:

• Infectious Diseases
• Clinical Microbiology
• Epidemiology

Background:

• Staphylococcus aureus bacteraemia (SAB) is a frequent and life-threatening condition.
• Optimal first-line antibiotic treatment for SAB remains debated due to a lack of randomized trials.

Purpose of the Study:

• To identify prognostic factors in patients with SAB.
• To analyze the impact of different first-line antibiotic treatments on SAB outcomes.

Main Methods:

• Prospective cohort study (VIRSTA) in eight French tertiary care centers.
• Inclusion of 2091 adult patients with S. aureus bacteraemia between April 2009 and October 2011.
• Multivariate logistic regression used to identify factors associated with 12-week case-fatality.

Main Results:

• The 12-week case-fatality rate was 34.0% (671/1972 patients).
• Independent prognostic factors for mortality included advanced age, septic shock, metastatic cancer, and unknown primary focus.
• For methicillin-sensitive S. aureus (MSSA) bacteraemia, antistaphylococcal penicillins and vancomycin were associated with better outcomes compared to other antibiotics.

Conclusions:

• Prognostic factors for SAB are largely non-modifiable.
• Initiating empiric treatment with antistaphylococcal penicillins or vancomycin may improve outcomes in MSSA bacteraemia.