Diabetes can damage this system. High levels of blood sugar make the kidneys filter too much blood. All this extra work is hard on the filters. After many years, they start to leak and useful protein is lost in the urine. Having small amounts of protein in the urine is called microalbuminuria.
In time, the stress of overwork causes the kidneys to lose their filtering ability. Waste products then start to build up in the blood. Finally, the kidneys fail. This failure, end-stage renal disease (ESRD), is very serious. A person with ESRD needs to have a kidney transplant or to have the blood filtered by machine (dialysis).