Evaluation of Empiric Voriconazole Dosing and Therapeutic Drug Monitoring in Hospitalized Pediatric Patients.

Invasive fungal infections are a significant cause of morbidity and mortality in children with immunodeficiencies. Current dosing recommendations for voriconazole often result in subtherapeutic exposure in pediatric patients. In this single-center retrospective study, we reviewed hospitalized pediatric patients receiving voriconazole with at least one inpatient serum trough concentration measured. Patient characteristics and voriconazole dosing courses with associated trough concentrations were summarized for all patients as well as grouped by age (0 to 1 y, 2 to 11 y, and 12 to 18 y). Of 106 included patients, the median age was 9 years (range, 29 d to 18 y). Five hundred ninety courses of voriconazole were administered with 365 associated troughs. Most troughs were subtherapeutic (49%) and 30% of patients never attained a therapeutic trough. The median oral daily dose associated with a therapeutic trough was higher in younger age groups: 21.6 mg/kg 0 to 1 year, 17.9 mg/kg 2 to 11, and 9.5 mg/kg 12 to 18 years ( P <0.001). Patients younger than 2 years had the largest proportion of subtherapeutic troughs and variability in dosing. Attainment of therapeutic voriconazole concentrations was challenging across all pediatric age groups. Higher starting doses for patients younger than 2 years are likely needed.