Normal Glomerular Filtration Rate in an 11-Year-Old Child
The normal glomerular filtration rate (GFR) for an 11-year-old child is approximately 120-130 mL/min/1.73 m².
Understanding Pediatric GFR Values
Glomerular filtration rate is the most practical measure of kidney function and varies significantly throughout childhood development. Unlike adults, where a GFR <60 mL/min/1.73 m² indicates chronic kidney disease, children have different reference ranges:
- For children and adolescents, abnormal GFR starts below 75 mL/min/1.73 m² 1
- By age 11, children have typically reached adult-equivalent GFR values when adjusted for body surface area
- The normal range for an 11-year-old is approximately 120-130 mL/min/1.73 m²
Measurement and Estimation Methods
Accurately determining GFR in children requires appropriate methods:
- Direct measurement using exogenous filtration markers (iohexol, inulin) is the gold standard but impractical for routine clinical use 2
- The revised Schwartz Formula is recommended for estimating GFR in children 2:
eGFR (mL/min/1.73 m²) = 0.413 × [height (cm) / serum creatinine (mg/dL)] - Adult formulas (CKD-EPI, MDRD, Cockcroft-Gault) significantly overestimate GFR in children and should not be used 3
Clinical Implications
Understanding normal GFR values is crucial for proper assessment:
- Annual screening for albuminuria with a random spot urine sample for albumin-to-creatinine ratio should be considered once a child has had diabetes for 5 years, starting at puberty or age >10 years 2
- Children with GFR <75 mL/min/1.73 m² should be referred for further clinical assessment 1
- Serum creatinine alone is insufficient for assessing renal function in children due to variations in muscle mass and body composition 2
Important Considerations
When evaluating GFR in children, several factors should be considered:
- GFR increases rapidly during infancy and then gradually with age and body size 4
- Children from birth to 1 year have adjusted GFR values below the adult range, but by age 11, values approach adult norms 5
- Body composition significantly affects GFR measurements, especially in children with atypical body mass 4
- The Full Age Spectrum (FAS) equation may provide improved validity and continuity across different age groups 6
Understanding the normal GFR range for an 11-year-old child is essential for proper assessment of kidney function and early detection of renal abnormalities.