This study is designed as a prospective, randomized, open-label trial evaluating antimicrobial utilization, clinical outcomes, and healthcare costs among patients with positive blood cultures. Patients will be randomized to one of the following FDA-cleared devices that will be used to assess the workflow impact of fast identification (ID) and antimicrobial susceptibility testing (AST) in the microbiology lab and in the quality of care in patients: 1) Standard culture and AST of positive blood culture bottles plus the Verigene® Blood Culture Gram-positive/Gram-negative kit (BC-GP/GN); or 2) Fast ID and AST of positive blood culture bottles using the Accelerate PhenoTest™ BC kit with the Accelerate Pheno™ System.

Inclusion Criteria:

• All positive blood cultures (including on-panel/off-panel/contaminants) identified during local laboratory business hours
• All adult (≥18 years of age)

Exclusion Criteria:

• Identification of blood culture positivity outside of local laboratory business hours (e.g. whenever laboratories are staffed to perform both rapid testing and routine testing)
• Positive blood culture in the prior week with same Gram stain result
• Transferred from an outside hospital and had a history of a previously positive blood culture of the same Gram stain result
• Previously enrolled in the study
• Only the first positive culture for each patient will be included during the study period; any subsequent episode of bloodstream infection (BSI) will be excluded
• Died or were transitioned to comfort care within 24 hours of enrollment
• Negative Gram-stain
• Not admitted to hospital for ≥ 24 hours following blood culture positivity