The glomeruli are the site where blood is filtered and urine is formed. They act as a selective membrane, allowing some substances to be excreted in the urine and other substances to remain in the body. As diabetic nephropathy progresses increasing numbers of glomeruli are destroyed, resulting in impaired kidney functioning. Protein may appear in the urine for 5 to 10 years before other symptoms develop.
Hypertension often accompanies diabetic nephropathy.
The disorder continues to progress, with end-stage renal disease developing within 2 to 6 years after the appearance of chronic renal failure or significant hypertension. The mechanism that causes diabetic nephropathy is unknown. It may be caused by inappropriate incorporation of glucose molecules into the structures of the basement membrane and the tissues of the glomerulus. The disorder affects about 4 out of 10,000 persons. The risk is related to the control of the blood-glucose levels .