Renal Function Descriptors in Neonates: Which Creatinine-Based Formula Best Describes Vancomycin Clearance?

Area of Science:

• Neonatal pharmacology
• Pediatric nephrology
• Drug metabolism and disposition

Background:

• Renal drug clearance, like vancomycin, is influenced by growth and maturation.
• Neonatal renal function is immature, necessitating accurate assessment for drug therapy.
• Existing serum creatinine (SCr)-based renal function descriptors are not optimized for neonates.

Purpose of the Study:

• To review neonatal kidney development and renal function assessment methods.
• To identify optimal renal function descriptors for estimating vancomycin clearance in neonates.
• To develop population pharmacokinetic models for vancomycin in a neonatal cohort.

Main Methods:

• Review of neonatal kidney development and renal function estimation.
• Application of various SCr-based renal function descriptors.
• Development of population pharmacokinetic models using age, weight, SCr, and renal function descriptors.
• Analysis of vancomycin clearance variability in a septic neonatal cohort.

Main Results:

• Incorporating SCr or renal function descriptors significantly reduced vancomycin clearance variability.
• Population pharmacokinetic models using Léger and modified Schwartz formulas were optimal.
• SCr and other tested renal function descriptors also provided good model fit.
• The study supports using renal function descriptors for vancomycin clearance estimation in neonates.

Conclusions:

• Renal function descriptors are valuable for estimating vancomycin clearance in neonates.
• Age, weight, and renal function descriptors improve pharmacokinetic model accuracy.
• Further validation of developed models with external data is recommended.