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

Inclusion Criteria: * CSAI caused by MSSA. CSAI is defined as MSSA BSI with a positive follow-up blood culture result for MSSA or the presence of a site of infection remote from the primary focus caused by hematogenous seeding (e.g. endocarditis, vertebral osteomyelitis) or extension of the infection beyond the primary focus (e.g. septic thrombophlebitis or abscess); or deep-seated infections caused by MSSA (e.g. osteoarticular infections, deepseated abscesses). * Current or intended treatment with cefazolin Exclusion Criteria: * Previous enrolment into the current study within 30 days * Hemodialysis (patients on hemofiltration are eligible) * Patients who are very likely to stop treatment with cefazolin in the next 48 hours as per treating physician (because of treatment failure, switch to oral medication, palliative care, allergy etc.) or who are very likely to be discharged in the next 48 hours as per treating physician. * Outpatients * Women who are pregnant (special pharmacokinetic) * Polymicrobial infection except concomitant isolation of a likely contaminant (e.g. Staphylococcus epidermidis or Propionibacterium acnes) or an anaerobic pathogen. If an additional pathogen is identified after inclusion of the patient into the study, the patient will remain in the study. * Not-complicated S. aureus infections: non-bacteremic skin- and soft tissue or small Joint infections without deep-seated abscesses (as these patients will be quickly switched to oral antibiotics) * CSA…