Point prevalence of appropriate antimicrobial therapy in a Dutch university hospital

Antimicrobial stewardship teams have been shown to increase appropriate empirical antibiotic therapy and reduce medical errors and costs in targeted populations, but the effect in non-targeted populations is still unclear. The aim of this study was to determine the prevalence of inappropriate antibiotic use in a large university hospital and identify areas in which antimicrobial stewardship will be the most effective. In a point prevalence survey we assessed the appropriateness of antibiotic therapy using an electronic surveillance system in combination with a standardized method for duration of therapy, dosage, dosage interval, route of administration, and choice of antibiotic drug. Patients using at least one antibiotic drug were included. Among 996 patients admitted in the surveyed wards, 337 patients (33.8 %) used one or more antibiotic drugs. Two hundred and twenty-one patients (22.2 %) used antibiotic medication therapeutically, with a total of 307 antibiotic prescriptions. Antibiotic therapy was deemed inappropriate in 90 (29.3 %) of these prescribed antibiotics, with an unjustified prescription as the most common reason for an inappropriate prescription. Use of fluoroquinolones and amoxicillin/clavulanic acid and a presumed diagnosis of fever of unknown origin, urinary tract infection, and respiratory tract infection were associated with inappropriate antibiotic therapy. Our study provides insight into the (in)appropriateness of antibiotic prescriptions in a tertiary care center in the Netherlands and identifies areas for improvement. The use of an electronic surveillance system for this point prevalence study is easy and may serve as a baseline measurement for the future effect of antibiotic stewardship.