Voriconazole concentration monitoring at an academic medical center

Abstract

Purpose. Results of a study of the relationship among voriconazole dosages, serum concentrations, adverse effects, and clinical outcomes are presented. Methods. A retrospective chart review was conducted that included all patients who had at least one voriconazole concentration drawn between July 1, 2009, and August 15, 2014, at a single academic medical center. The primary outcome was the proportion of patients with initial voriconazole concentrations in the target range. Results. Forty-seven of 88 patients (53%) had an initial voriconazole concentration within the target range, 27% (24 of 88) of patients had a concentration above the range, and 19% (17 of 88) had a concentration below the range. Sixty-seven percent of patients with above-target concentrations had adverse effects. Voriconazole was discontinued in 9% of patients, and dosages were reduced in 11% of patients because of adverse effects. Voriconazole for treatment versus prophylaxis was analyzed in a subgroup, as was obesity and nonobesity. Twenty-four percent of patients died during their hospital admission, and 14% were not discharged on voriconazole therapy. The within-target group had the highest proportion of patients discharged on voriconazole and the lowest proportion of deaths. Conclusion. A retrospective study in one institution revealed that the first measured voriconazole concentration was within the target range in 53% of patients and that dosage was modified in only 51% of patients whose concentration was outside of that range. The majority of patients with above-target concentrations had an adverse effect, and this result was particularly common in patients with a body mass index of ≥35 kg/m2.