Achieving therapeutic vancomycin levels in pediatric patients.

BACKGROUND Vancomycin is widely used to treat infections caused by methicillin-resistant Staphylococcus aureus. Data for dosing and monitoring of this drug in pediatric patients are lacking, and clinicians who are treating children often follow guidelines established for adults. OBJECTIVES To examine the total daily doses of vancomycin required to reach therapeutic trough levels (i.e., 10-20 mg/L) in infants, children, and adolescents, and to assess the number of pediatric patients in whom therapeutic trough levels are achieved with current empiric doses (40-60 mg/kg daily). METHODS This chart review evaluated patients 1 month to 18 years of age for whom vancomycin was prescribed at a single institution between November 2011 and October 2012. Patients' demographic characteristics, vancomycin dosing parameters, and subsequent steady-state trough concentrations were analyzed. RESULTS Overall, the proportion of patients who reached therapeutic trough levels with current empiric doses was 39% (74 of 188). The mean total daily dose (± standard deviation) required to achieve therapeutic trough levels was 57.8 ± 11.5 mg/kg for patients 1 to 5 months of age, 68.9 ± 15.4 mg/kg for those 6 to 23 months of age, 65.8 ± 13.0 mg/kg for those 2 to 12 years of age, and 55.7 ± 11.8 mg/kg for those 13 to 18 years of age. CONCLUSIONS Common empiric vancomycin dosing regimens (40-60 mg/kg daily) are not high enough to achieve trough levels of 10-20 mg/L in the majority of pediatric patients. Given these data, the authors suggest a starting dose of 60 mg/kg daily for patients 1 to 5 months of age and those 13 to 18 years of age and a starting dose of 70 mg/kg daily for patients 6 months to 12 years of age.