Stages of CKD

Chronic kidney disease (CKD) is progressive and irreversible. It is defined as either kidney damage or a GFR of < 60 mL/min/1.73 m² for 3 or more months. The most common causes of CKD are diabetes mellitus (DM) and hypertension (HTN). Other causes include recurrent pyelonephritis, glomerulonephritis, and polycystic kidney disease. The pathophysiology is characterized by glomerulosclerosis and interstitial inflammation and fibrosis leading to a decline in kidney function. The GFR declines as nephrons are rendered nonfunctional due to tubulointerstitial damage and diminished perfusion, which generates ischemia to the remaining nephrons.