The aim of this thesis was to stimulate rational and effective use of antimicrobials, by addressing the first two cornerstones: (1) refining stewardship of existing antimicrobials and (2) re... Show moreThe aim of this thesis was to stimulate rational and effective use of antimicrobials, by addressing the first two cornerstones: (1) refining stewardship of existing antimicrobials and (2) re-introducing old antibiotics within the framework of antimicrobial stewardship. The overall aim is to contribute to antimicrobial stewardship and to explore the value of the re-introduction of old antibiotics that are currently scarcely used. The basic step is the in vitro relationship expressed as minimal inhibitory concentration (MIC) for a given bacteria for a given antibiotic. The next step is the in vivo situation. This thesis concentrates on the in vivo situation. Show less
Renal clearance is responsible for the elimination of a large number of water-soluble drugs and metabolites and is therefore of large importance when characterizing the pharmacokinetics of drugs.... Show moreRenal clearance is responsible for the elimination of a large number of water-soluble drugs and metabolites and is therefore of large importance when characterizing the pharmacokinetics of drugs. Renal clearance includes glomerular filtration, tubular secretion and reabsorption and each of these processes is subject to different developmental changes. To estimate the renal clearance of drugs in children, a thorough understanding of these developmental changes in the different subprocesses contributing to renal function is needed. Therefore the aim of the research described in this thesis was to characterize the developmental changes in renal function over the entire pediatric age range. To this end, a system-based pharmacology approach was applied implicating that within the models for the different subprocesses contributing to renal function a distinction was made between system-specific and drug-specific properties. The transition to a more system-based pharmacology approach and the combination of different strategies (extrapolation to other drugs, adult data or non-clinical data) will result in an approach focusing on the underlying system instead of focusing on the drugs and may facilitate development of pharmacokinetic models and evidence-based dosing regimens in the pediatric population. Show less