KDIGO CKD Staging — Chronic Kidney Disease Classification

The KDIGO 2012 classification system for chronic kidney disease (CKD) uses eGFR and albuminuria to stage kidney disease severity and stratify risk for CKD progression, kidney failure, and cardiovascular complications. CKD is defined as abnormalities of kidney structure or function present for >3 months with health implications. Staging guides management intensity, nephrology referral, medication adjustment, and transplant evaluation.