Estimated Glomerular Filtration Rate (eGFR)
eGFR is essential for dosing adjustments in children with renal impairment.
Modified Bedside Schwartz
The following equations are a guide to calculating estimated glomerular filtration rate in children:
35 × height (cm) / serum creatinine (micromol/L)
30 × height (cm) / serum creatinine (micromol/L)
* The values used in these formulas may differ according to locality or laboratory method.
CKiD U25 GFR Equation
Derived using data from the Chronic Kidney Disease in Children Study (CKiD), the CKiD U25 GFR estimating equations can also be used for estimating GFR in patients with CKD using serum creatinine and/or cystatin C.
CKiD Under 25 (U25) Estimated GFR Calculator - kidney.wiki ↗Formal GFR Measurement (Iohexol)
When there is clinical concern about a patient's GFR, a formal GFR measurement can be performed at Evelina London Children's Hospital.
What is it?
Iohexol GFR measurement is a highly accurate, reference method to measure GFR. It involves injecting iohexol (a harmless contrast dye) into the bloodstream and taking timed blood samples to track its clearance by the kidneys. This offers better accuracy than routine creatinine-based estimates.
- Visit Type: Half-day hospital visit
- Results: Available in approximately 3 months
Refer to the Evelina paediatric kidney team via email:
gstt.elchpaedrenalreferrals@nhs.net
📊 Other Dosing Tools
Vancomycin Dosing Nomogram
PDFGentamicin Dosing in Children
External💊 Formulary & Guidelines
Essential drug information and prescribing guides.
Renal Drug Monographs
A-Z guide of drugs requiring dose adjustment in renal impairment. These can be accessed through the Clinibee platform by requesting access to the ELCH paediatric formulary.
Visit Clinibee ↗Medusa (Injectable Medicines)
NHS Injectable Medicines Guide. Guidance on preparation/administration and Y-site compatibility charts for common renal infusions and antibiotic combinations.
Visit Medusa (Log in required) ↗Medicines for Children
Practical and reliable information about medicines for parents and carers from the RCPCH.
Visit RCPCH Resource ↗⚠️ Safety Alerts
Important: Tacrolimus Brands
Patients should remain on the same brand of Tacrolimus (e.g., Prograf, Adoport, Envarsus) unless directed by a consultant. Switching brands can alter blood levels.
Vancomycin - Reduced GFR Risk
Patients with reduced GFR (either due to acute kidney injury or chronic kidney disease) are at greater risk of side-effects because the drug is predominantly excreted by the kidneys.