Diabetic nephropathy is the term used to describe kidney damage that occurs in diabetes, usually of long-standing. The damage to the kidney in diabetes can result from the high blood sugar itself, which leads to an expansion of certain types of material in the filtering mechanism of the kidney. This expansion damages the delicate cells responsible for filtering waste materials through the kidney. Eventually, there are abnormal pressures and changes in the important electrical balance in this complex structure.
These changes lead to leakage of proteins that are usually either retained or reabsorbed by the kidney. The blood pressure can rise due to overload of fluid and constriction of small blood vessels. The rise in blood pressure further damages the kidney if not treated. If there is an excessive leak of protein, the body becomes protein deficient, which can lead to generalized puffiness and swelling. Eventually, the kidneys can fail and their functions must be replaced by the processes of either hemodialysis (blood filtering and removal of wastes through a machine) or peritoneal dialysis (a simpler process whereby wastes are exchanged into fluids introduced into the abdominal cavity), or a kidney transplant is required.
Although complete kidney failure is not a common outcome in diabetes in percentage terms, diabetes is the most common cause of kidney failure in working age adults and occurs in more than 25,000 people each year in the United States. Kidney failure is extremely disruptive to the sufferer’s life and is very expensive to treat. The tendency to get diabetic kidney damage has an inherited component, so that if a close relative with diabetes suffers from it, an individual is more likely to experience it. However, it can be delayed or even prevented. Good control of blood sugar and blood pressure, together with use of certain types of drugs known as ACE-inhibitors or ARBs, has been shown to markedly slow progression of diabetic kidney damage. Moreover, it can be detected very early by sensitive tests in common use.