Assessment of eGFR 71 and Creatinine 1.12
An eGFR of 71 mL/min/1.73 m² with a creatinine of 1.12 mg/dL represents mildly decreased kidney function (CKD Stage 2), not normal renal function, though it does not yet meet the threshold for clinically significant chronic kidney disease.
Understanding the Classification
According to the KDIGO guidelines, kidney function is staged as follows 1:
- Stage 1: eGFR ≥90 mL/min/1.73 m² (normal or increased GFR with kidney damage)
- Stage 2: eGFR 60-89 mL/min/1.73 m² (mild decrease in GFR)
- Stage 3: eGFR 30-59 mL/min/1.73 m² (moderate decrease in GFR)
Your eGFR of 71 places you in Stage 2, which represents a mild decrease from the expected normal range of 75-100 mL/min/1.73 m² 1.
Why Creatinine Alone is Misleading
The creatinine level of 1.12 mg/dL may appear "normal" by traditional laboratory reference ranges (0.8-1.3 mg/dL for men, 0.6-1.0 mg/dL for women) 1. However, serum creatinine is a poor standalone indicator of kidney function because it doesn't significantly rise until GFR has already decreased by at least 40% 1.
Key factors affecting creatinine interpretation 1:
- Muscle mass: Lower muscle mass (elderly, women) produces less creatinine, masking kidney dysfunction
- Age: Creatinine decreases with age even as kidney function declines
- Body composition: A 1.2 mg/dL creatinine could represent 110 mL/min GFR in a young muscular male or only 40 mL/min in an elderly woman
Clinical Significance of eGFR 71
The KDIGO guidelines explicitly state that eGFR levels <60 mL/min/1.73 m² should be reported as "decreased" 1. Your eGFR of 71 is above this threshold, meaning:
- No diagnosis of CKD is made based on eGFR alone unless kidney damage markers (proteinuria, hematuria, structural abnormalities) are present 1
- This level does not require nephrology referral or intensive CKD management protocols 2
- Most medications do not require dose adjustment until eGFR falls below 60 mL/min/1.73 m² 3
Important Caveats and Next Steps
Duration matters: CKD is only diagnosed if the decreased function persists for >3 months 1. A single measurement is insufficient.
Check for kidney damage markers 1:
- Measure urine albumin-to-creatinine ratio (ACR) to assess for proteinuria
- If ACR ≥30 mg/g, this confirms kidney damage and establishes CKD diagnosis even with eGFR >60
- Repeat eGFR measurement in 3-6 months to confirm stability 2
Consider confirmatory testing if borderline: For eGFR 60-89 mL/min/1.73 m², KDIGO suggests measuring cystatin C if confirmation is needed, though this is typically reserved for eGFR 45-59 range 1.
Monitoring Recommendations
For eGFR 60-89 (Stage 2 CKD) 2:
- Annual monitoring of eGFR and albuminuria is sufficient if stable
- No specific CKD management protocols are required unless proteinuria is present
- Address cardiovascular risk factors (hypertension, diabetes, smoking) as these accelerate progression
Bottom line: While not "normal" by strict definition (normal is 90-120 mL/min/1.73 m²), an eGFR of 71 represents only mild reduction that typically requires monitoring rather than intervention, provided no proteinuria or other kidney damage markers are present 1.