eGFR Calculation for 61-Year-Old Female with Serum Creatinine 0.6 mg/dL
For a 61-year-old female with serum creatinine 0.6 mg/dL, the estimated GFR is approximately 98-105 mL/min/1.73 m² using the CKD-EPI equation, which represents normal kidney function. 1, 2
Calculation Method
The CKD-EPI equation without race is the recommended formula for GFR estimation in adults, as it provides superior accuracy compared to older equations, particularly at GFR values >60 mL/min/1.73 m². 2, 3
Using the CKD-EPI equation for a 61-year-old female with creatinine 0.6 mg/dL yields an eGFR of approximately 98-105 mL/min/1.73 m², depending on the specific CKD-EPI variant used (2009 vs 2021 race-free equation). 2, 3
The MDRD equation (eGFR = 186 × [0.6]^-1.154 × 61^-0.203 × 0.742) would yield approximately 102 mL/min/1.73 m², though this equation is less accurate at higher GFR values. 2
Clinical Interpretation
An eGFR ≥90 mL/min/1.73 m² is considered normal kidney function, with values declining by approximately 1% per year after age 40 years. 2
This patient's eGFR of approximately 98-105 mL/min/1.73 m² does not meet criteria for chronic kidney disease (CKD), which requires eGFR <60 mL/min/1.73 m² or albuminuria ≥30 mg/g creatinine. 2
Normal GFR is approximately 130 mL/min/1.73 m² for young adults, with expected age-related decline making this patient's eGFR appropriate for her age. 2
Critical Caveats
Never use serum creatinine alone to assess kidney function, as it is affected by muscle mass, creatinine generation, tubular secretion, and extrarenal excretion independent of GFR. 1, 2
In elderly patients with low muscle mass, a "normal" serum creatinine can mask significant renal impairment—a creatinine of 1.2 mg/dL can represent creatinine clearance of 110 mL/min in a young adult but only 40 mL/min in an elderly patient. 1
Clinical laboratories should report eGFR rounded to the nearest whole number using units of mL/min/1.73 m², with values <60 mL/min/1.73 m² flagged as low. 2
Extremes of muscle mass, obesity, amputees, or non-steady-state conditions may yield inaccurate GFR estimates. 2