Stage 5 kidney failure is defined by a GFR value less than what threshold (mL/min/1.73 m2)?

• A. < 15 (or dialysis)
• B. 15-29
• C. 30-59
• D. 60-89

Answer: (A)

Stage 5 CKD represents end-stage kidney disease, defined when estimated GFR falls below 15 mL/min/1.73 m^2. This threshold marks when kidney function is insufficient to sustain metabolic and fluid balance, so renal replacement therapy—usually dialysis or kidney transplantation—is typically required. GFR is estimated from serum creatinine using formulas that account for age, sex, and body size, and clinicians use these stages to gauge progression and plan treatment.