Patients are dosed using two timed vancomycin serum concentrations

Patients are dosed based on one timed vancomycin serum level

The dose is calculated based on 2 vancomycin serum levels

Therapeutic success will be assessed as therapeutic cure (composite endpoint)or therapeutic failure (composite endpoint). Therapeutic cure is defined as clinical cure and/or microbiologic cure . Clinical cure is defined as the absence of infection signs/symptoms without the need for additional antibiotic treatment. Microbiologic cure is defined as negative blood cultures at 5 days after vancomycin treatment initiation. Therapeutic failure includes at least one of the following -clinical failure, microbiologic failure, premature discontinuation due to ADR or all-cause mortality. Clinical failure is defined as insufficient clinical response to initial vancomycin therapy necessitating antibiotic change. Microbiological failure is defined as a positive culture at ≥ 5 days after initiation of vancomycin treatment.

The hospital and treatment related costs will be compared between the two study arms, from a hospital perspective, associating the clinical outcomes mentioned in Outcome 1 above. The arm showing least costs will be determined as more beneficial to the healthcare system.