Therapeutic drug monitoring in patients treated with vancomycin: a single center, prospective, observational, real-world study.

Purpose: Therapeutic drug monitoring of vancomycin targeting an AUC/MIC ratio of 400-650 mg*h/L is required to ensure optimal therapeutic efficacy and safety in patients treated with vancomycin. The objectives of this study were to monitor vancomycin plasma peak and trough concentrations to calculate the area under the curve (AUC) to assess target achievement in real-world settings and to evaluate the relationship between AUC and acute kidney injury (AKI).

Methods: In this single-center cohort study, prospectively calculated vancomycin AUC and trough concentrations were extracted from the database and evaluated for achievement of therapeutic ranges for AUC and trough concentrations at a university hospital. Patients were evaluated for the development of AKI according to KDIGO guidelines.

Results: A total of 114 patients were included in the study. Vancomycin loading doses were initiated in 83.3% of patients, and 82.1% of patients received the appropriate weight-based dose. 79.8% of maintenance doses were appropriate. The median (min-max) values for peak, trough, and AUC were 23.25 (3.3-131.8) mg/L, 10.35 (0.6-56.4) mg/L, and 403(49-1786) mg/L*hour, respectively. The majority of values were outside the therapeutic target for both trough (65.3%) and AUC (63.7%). AKI was observed in 15.8% of patients. In patients without AKI, the median (min-max) trough concentration was 9.65 (0.60-45.30) mg/L and the AUC was 370 (49-1390) mg/L*hour.

Conclusions: In this study, only one-third of baseline concentrations were in the therapeutic range and were increased by up to two-thirds with dose adjustments. Therapeutic drug monitoring to achieve target concentrations is critical in patients treated with vancomycin.