Some experts will argue that GFR is not a suitable indicator for the assessment of kidney functions in neonates, however w don’t actually have much of a choice because the limited data available for neonates. Some experts prefer to use the serum creatinine level as a better indicator for kidney functions in neonates.

Many antibiotics are not studied in pediatrics and neonates, when it comes to renal dose adjustment, many data are derived from adult data and adjusted for age and BSA.

When performing renal dose adjustments for antibiotics (AB) in neonates, it involves several important considerations beyond just the glomerular filtration rate (GFR). While GFR is a critical factor as it reflects kidney function and drug clearance, dosing adjustments in neonates must also consider:

1. Maturational Changes: Renal function is immature at birth and rapidly develops during the neonatal period. The pharmacokinetics (absorption, distribution, metabolism, and elimination) are influenced by the neonate’s age, weight, and postmenstrual age.

2. Drug Characteristics: Different antibiotics have varying properties, including molecular size, protein binding, volume of distribution, and renal elimination fraction, all of which impact dosing.

3. Hydration and Fluid Status: Neonates often experience fluid shifts, which can affect drug clearance and distribution.

4. Serum Drug Levels (if applicable): For some antibiotics, like aminoglycosides and vancomycin, therapeutic drug monitoring (TDM) is essential to guide dosing.

5. Renal Maturity: Neonates, especially preterm ones, have reduced tubular function and decreased renal blood flow, affecting drug elimination differently than in older children or adults.