Probability of Target Attainment With Standard Intermittent Bolus Administration of Cefazolin in Patients With Complicated Infections Caused by Staphylococcus Aureus

Given the paucity of pharmacological data on cefazolin treatment of Methicillin-susceptible S. aureus (MSSA) complicated S. aureus infection (CSAI), the primary purpose of this study is to investigate the probability of pharmacological target attainment (in the blood and infected tissue) with standard intermittent bolus administration of cefazolin in patients with CSAI caused by MSSA by determining plasma concentrations of cefazolin and exact Minimum inhibitory concentration (MICs) of the causative MSSA strains in patients with various disease severities (e.g. critically ill vs. noncritically ill patients). * Sub-study quantitative measurement of Torque Teno virus (TTV): The primary purpose of this sub-study is to describe the viral kinetics of TTV in CSAI patients and to explore the association of TTV viremia with clinical outcomes and molecular markers of activation of the immune system. * Sub-study investigating antibiotic concentrations in sweat as a non-invasive therapeutic drug monitoring