Background. In 2008, the empiric vancomycin dosing recommendation in children at our institution was changed from 40 to 60 mg/kg per day. Subsequently, an increased incidence of acute kidney injury (AKI) in patients receiving vancomycin was suspected. The objective of this study was to evaluate AKI in children receiving vancomycin and to determine risk factors for AKI development.Methods. Medical records of patients aged 30 days through 17 years who received vancomycin for at least 72 hours between January and December 2007 (40 mg/kg per day) and January and December 2010 (60 mg/kg per day) were reviewed. Patients with cystic fibrosis, an elevated baseline serum creatinine, or without a serum creatinine concentration obtained after receipt of vancomycin were excluded. Acute kidney injury was defined using adapted pediatric RIFLE criteria as an increase in serum creatinine from baseline of 50% or more. BACKGROUNDVancomycin is commonly used in the pediatric population for empiric or targeted treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections and has been associated with acute kidney injury (AKI) [1].Empiric intravenous (IV) vancomycin in children has traditionally been dosed as 40 mg/kg per day in 4 divided doses to achieve target serum trough concentrations of 5-10 mg/L. Recent evidence and recommendations suggest that such doses are unlikely to achieve the goal serum trough concentrations (10-20 mg/L) that are necessary for the optimal area under the curve (AUC) for plasma concentration relative to the organism minimum inhibitory concentration (MIC) (AUC/MIC) [2][3][4][5].

The study objective was to evaluate the population pharmacokinetics and pharmacodynamics of extended-infusion piperacillintazobactam in children hospitalized in an intensive care unit. Seventy-two serum samples were collected at steady state from 12 patients who received piperacillin-tazobactam at 100/12.5 mg/kg of body weight every 8 h infused over 4 h. Population pharmacokinetic analyses were performed using NONMEM, and Monte Carlo simulations were performed to estimate the piperacillin pharmacokinetic profiles for dosing regimens of 80 to 100 mg/kg of the piperacillin component given every 6 to 8 h and infused over 0.