Thinning of renal cortex refers to prolonged renal disease, repeated stimulation of the kidneys, resulting in repeated damage to the kidneys, gradual atrophy of the renal units to become fewer, and imaging tests suggesting thinning of the renal cortex. Common diseases include chronic glomerulonephritis, chronic pyelonephritis, obstructive nephropathy and so on. 1. Chronic glomerulonephritis: Chronic glomerulonephritis has a prolonged condition, and the examination may reveal different degrees of renal cortex thinning on both sides of the kidneys, which is mainly manifested by hematuria, proteinuria, hypertension and edema. 2. Chronic pyelonephritis: When chronic pyelonephritis occurs, the chronic inflammation caused by the kidney will lead to the damage of the renal interstitium, renal pelvis and renal calyces, and the phenomenon of thinning of the renal cortex will also occur. 3. Obstructive nephropathy: prolonged urinary stones and tumors can lead to fluid retention in the kidneys, and the continuous progress of the disease can lead to the problem of thinning of renal cortex. Besides, diabetic nephropathy, hypertensive nephropathy and so on can also lead to thinning of renal cortex. When the examination finds thinning of renal cortex, you should go to regular hospitals in time to clarify the cause of the disease and take treatments under the guidance of doctors so as not to delay the condition.