What is a normal eGFR score for a 63-year-old male with type 2 diabetes, single kidney, cholelithiasis, hepatic steatosis, and slightly enlarged spleen, with well-controlled hyperlipidemia and hypertension?

Normal eGFR for a 63-Year-Old Male with Type 2 Diabetes and Single Kidney

For this patient with a solitary kidney, an eGFR of 45-60 mL/min/1.73 m² should be considered acceptable, though not truly "normal," as single kidney status physiologically reduces total filtration capacity by approximately 50% compared to two functioning kidneys. 1

Understanding eGFR in Single Kidney Context

Standard eGFR Reference Values

• Normal eGFR in the general population is ≥60 mL/min/1.73 m² 1
• eGFR persistently <60 mL/min/1.73 m² in concert with urine albumin >30 mg/g creatinine is considered abnormal 1
• The CKD-EPI equation is the preferred formula for calculating eGFR 1

Single Kidney Considerations

The critical distinction for this patient is that having one kidney inherently reduces total glomerular filtration capacity. A person with one healthy kidney typically achieves 60-70% of the filtration rate of someone with two kidneys due to compensatory hyperfiltration in the remaining kidney. Therefore:

• An eGFR of 45-60 mL/min/1.73 m² (CKD Stage 3a) may represent adequate function for a single kidney 1, 2
• An eGFR below 45 mL/min/1.73 m² (CKD Stage 3b or worse) warrants increased concern and monitoring 1, 2

Risk Stratification Based on Current Status

This Patient's Favorable Factors

• HbA1c of 6.3% indicates excellent glycemic control 1
• Controlled hypertension and cholesterol reduce cardiovascular and renal risk 1
• Non-smoker status eliminates a major risk factor for CKD progression 3

This Patient's Risk Factors

• Hepatic steatosis (fatty liver) is independently associated with increased CKD risk in type 2 diabetes (hazard ratio 1.49 after adjustment for confounders) 4
• Single kidney status requires more vigilant monitoring 1
• Age 63 years with diabetes increases baseline CKD risk 3

Clinical Management Thresholds

Monitoring Frequency by eGFR Level

Based on the risk stratification grid: 1

• eGFR 45-59 mL/min/1.73 m² (Stage 3a): Monitor 1-2 times per year 1, 2
• eGFR 30-44 mL/min/1.73 m² (Stage 3b): Monitor 2-3 times per year 1, 2
• eGFR <30 mL/min/1.73 m² (Stage 4): Refer to nephrology and monitor 3-4 times per year 1

Essential Additional Testing

Urine albumin-to-creatinine ratio (UACR) is mandatory for complete risk assessment: 1

• Normal UACR is <30 mg/g creatinine 1
• Two of three specimens collected within 3-6 months should be abnormal before confirming high albuminuria 1
• Avoid testing within 24 hours of exercise, during infection, fever, marked hyperglycemia, or marked hypertension 1

Medication Considerations for Renal Protection

Preferred Agents for This Patient

Given the single kidney and diabetes, SGLT2 inhibitors and GLP-1 receptor agonists are strongly recommended: 1

• SGLT2 inhibitors (empagliflozin, canagliflozin, dapagliflozin) can be initiated if eGFR >20 mL/min/1.73 m² and provide cardiovascular and renal protection 1
• Semaglutide (GLP-1 RA) is a preferred first-line agent with no dose adjustment needed for any level of kidney function 5
• Metformin is safe and beneficial down to eGFR 30 mL/min/1.73 m² with dose reduction required when eGFR falls below 45 mL/min/1.73 m² 1, 6

Dosing Adjustments

• Metformin should not be started if eGFR <45 mL/min/1.73 m² 1
• Metformin should be stopped if eGFR <30 mL/min/1.73 m² 1
• SGLT2 inhibitor glucose-lowering efficacy decreases below eGFR 45 mL/min/1.73 m², but cardiovascular and renal benefits persist 1

Critical Pitfalls to Avoid

Do not assume "normal" eGFR standards apply to single kidney patients - the compensatory hyperfiltration in the remaining kidney means that even an eGFR of 50-60 mL/min/1.73 m² may represent appropriate function 1

Monitor eGFR slope (rate of decline) as a predictor of complications - rapid eGFR decline is associated with increased all-cause mortality (HR 2.31), cardiovascular events (HR 1.73), and ESKD (HR 1.54) 7

The presence of hepatic steatosis increases this patient's CKD risk by approximately 50% despite other well-controlled factors 4

Avoid volume depletion if SGLT2 inhibitors are initiated - may need to reduce diuretic doses and educate about dehydration symptoms 1