A thin kidney cortex indicates that the patient has been suffering from chronic kidney disease for a long time. The kidney consists of two parts: the kidney cortex and the kidney medulla, of which the kidney cortex is thicker and performs most of the kidney functions. If the kidney cortex is thin, it means that the kidney function is gradually decreasing, and eventually it may develop into kidney failure. Some of the more common causes of kidney cortex thinning are chronic glomerulonephritis, chronic pyelonephritis, obstructive nephropathy, lupus nephritis, diabetic nephropathy and so on. These diseases can lead to repeated kidney damage, gradual atrophy of kidney units, and a gradual decline in function, eventually leading to a thinning of the renal cortex. When thinning of the renal cortex is detected, you should first actively look for these causes mentioned above and deal with them from the etiology to prevent further aggravation of the thinning of the renal cortex. In addition, it is also important to plan for the possibility that hemodialysis may be required for treatment at a later stage.