The Five Stages of Kidney Disease, Explained Plainly

Kidney disease is staged using the estimated glomerular filtration rate (eGFR), a number calculated from your blood creatinine, age and sex. The stage tells how much filtering capacity remains. Stage G1 means normal filtering (eGFR 90 or above) with other signs of kidney damage. G2 is mildly reduced (60 to 89). G3 is a moderate reduction (30 to 59). G4 is severe (15 to 29). G5 is kidney failure (below 15). The amount of protein in the urine is a separate and important risk marker. A complete picture needs both the eGFR and a urine albumin result, not just one number. A stage is a guide, not a sentence. Many people live well for years in the early and middle stages with good blood-pressure control and regular check-ups.