GFR 55 Indicates Stage 3a Chronic Kidney Disease
A GFR of 55 mL/min/1.73 m² corresponds to Stage 3a chronic kidney disease (CKD), defined as moderately decreased kidney function with GFR between 45-59 mL/min/1.73 m². 1, 2
Understanding the Classification
- The KDIGO and KDOQI classification systems subdivide Stage 3 CKD into two categories (3a and 3b) because mortality and adverse outcome risks differ substantially between these subgroups 1, 2
- Stage 3a specifically encompasses GFR values of 45-59 mL/min/1.73 m² 1, 2
- Your GFR of 55 falls squarely within this Stage 3a range 2
Critical Point: Complete Classification Requires Albuminuria Assessment
The diagnosis is incomplete without measuring albuminuria. The full CKD classification requires both GFR category AND albuminuria measurement to properly assess risk and guide treatment 2, 3
The three albuminuria categories are:
- A1: <30 mg/g creatinine (normal to mildly increased)
- A2: 30-299 mg/g creatinine (moderately increased)
- A3: ≥300 mg/g creatinine (severely increased) 2
Your complete classification would be:
- G3a/A1 (if albuminuria is normal): Moderate risk requiring annual monitoring 2
- G3a/A2 or G3a/A3 (if albuminuria is elevated): High to very high risk requiring monitoring 2-3 times yearly and possible nephrology referral 2, 3
Important Diagnostic Caveat
A single GFR measurement does not establish chronic kidney disease. The diagnosis requires abnormalities to be present for >3 months to differentiate from acute kidney injury 2, 4, 3
Clinical Implications at Stage 3a
At this stage, several management steps are required:
- Medication review: Adjust doses of all renally-cleared drugs 2, 3
- Blood pressure control: Target ≤140/90 mmHg if no albuminuria; consider ACE inhibitors or ARBs if diabetes with hypertension and any albuminuria 2, 3
- Monitoring frequency: Minimum annual assessment of both eGFR and urine albumin-to-creatinine ratio 1, 2, 3
- Nephrology referral: Recommended if severely increased albuminuria (A3 category) is present, but not necessary for Stage 3a with normal albuminuria and stable function 2, 3