What are the management and treatment recommendations for a patient with an estimated Glomerular Filtration Rate (eGFR) of 88, indicating near normal kidney function?

Management of eGFR 88 mL/min/1.73 m²

An eGFR of 88 mL/min/1.73 m² represents normal to mildly decreased kidney function (Stage G1-G2) and requires no specific kidney-focused interventions beyond standard cardiovascular risk management and annual monitoring if other kidney damage markers are absent. 1

Classification and Clinical Significance

• This eGFR falls within the normal range for adults, particularly for women (90-120 mL/min/1.73 m²) and is only slightly below the young male range (100-130 mL/min/1.73 m²). 1
• An eGFR >60 mL/min/1.73 m² does not constitute chronic kidney disease unless accompanied by other markers of kidney damage such as albuminuria ≥30 mg/24 hours, structural abnormalities on imaging, or persistent hematuria lasting ≥3 months. 1, 2
• The threshold for defining CKD is eGFR <60 mL/min/1.73 m², representing loss of half or more of normal kidney function. 1

Required Screening and Monitoring

Check for albuminuria using urine albumin-to-creatinine ratio (UACR) to determine if kidney damage is present despite normal eGFR. 3, 2

• If UACR is <30 mg/g and no other kidney damage markers exist, this patient does not have CKD. 2
• Repeat eGFR and UACR annually to monitor for development of kidney disease. 3
• No screening for CKD complications (anemia, mineral bone disease, metabolic acidosis) is indicated at this eGFR level, as these complications occur when eGFR falls below 45-60 mL/min/1.73 m². 4, 3

Management Approach

Focus on cardiovascular risk reduction rather than kidney-specific interventions:

• Implement standard blood pressure control targeting <130/80 mmHg if hypertension or diabetes is present. 3
• Use statins for cardiovascular risk reduction based on standard cardiovascular risk assessment, not kidney function. 2
• Avoid nephrotoxic medications, particularly NSAIDs, which reduce renal blood flow and can precipitate acute kidney injury. 3, 2
• No dietary protein restriction is needed; normal protein intake is appropriate. 3

Medication Considerations

• No medication dose adjustments are required at eGFR 88 mL/min/1.73 m². Dose adjustments typically begin when eGFR falls below 60 mL/min/1.73 m². 3
• All standard medications can be prescribed at normal doses. 3

When to Refer to Nephrology

Nephrology referral is not indicated for isolated eGFR of 88 mL/min/1.73 m². 4

Referral becomes appropriate only if: 4, 2

• eGFR falls below 30 mL/min/1.73 m²
• Persistent albuminuria ≥300 mg/g (ACR ≥30 mg/mmol) develops
• Abrupt sustained decrease in eGFR >20% occurs
• Urinary red cell casts or RBC >20 per high power field appear
• Rapidly progressive kidney disease develops

Critical Pitfalls to Avoid

• Do not diagnose CKD based solely on a single eGFR measurement. CKD requires persistent abnormalities for ≥3 months. 1
• Do not use serum creatinine alone to assess kidney function; always calculate eGFR. 1
• Be aware that extremes of muscle mass, acute illness, recent surgery, or hydration status can affect eGFR accuracy. 1
• Consider measuring cystatin C-based eGFR if the creatinine-based estimate seems discordant with the clinical picture, particularly in patients with extremes of muscle mass. 3, 5
• Higher eGFR values (>90-105 mL/min/1.73 m²) may paradoxically be associated with increased mortality risk, possibly due to inadequacies of the eGFR formula at low serum creatinine levels, but this does not change clinical management. 6