Combination Antibiotic Therapy for Staphylococcus Aureus Bacteremia

Staphyloccocus aureus bacteremia (SAB) is a common infectious disease condition in hospitalized patients which is associated with significant morbidity, excessive costs, and high mortality, despite effective antibiotic therapy. This pragmatic study is designed to test the hypothesis that outcomes in adults hospitalized with SAB will be improved by using combination antibiotic therapy (CAT) as early, targeted therapy in a high-risk subgroup. A group of patients identified early in their course as meeting at least one high-risk criterion who have no contraindications will be treated with one of two antibiotic strategies commonly used within usual care, namely: 1) antibiotic monotherapy or 2) combination antibiotic therapy, depending on the random assignment for each hospital, each month. Low-risk patients will be treated per usual care. Data from all patients admitted to participating hospitals with SAB will be included in the analysis.

Inclusion criteria

• Age ≥18 years
• Alive and admitted to an Intermountain Health (IH) hospital acute care unit at enrollment
• Initial positive blood culture with either methicillin-resistant Staphylococcus aureus (MRSA) or methicillin-susceptible Staphylococcus aureus (MSSA), collected:

• on or during the index admission to an IH hospital, or
• in an ambulatory setting (laboratory, clinic or emergency department) within 48 hours of the index admission, or
• at a non-IH network hospital within 24 hours of subsequent transfer to an IH hospital

Exclusion criteria

• Patient requests that patient health data not be included in the analysis