Taken from NKF Newsletter (2010 Issue 1) - PP9314/08/2010 (025329)
Millions of blood vessels act as filter inside a kidney. Their job is to remove waste products from the blood. When blood vessels in the kidneys are injured, kidneys cannot clean the blood properly. The body will retain more water and salt than it should, which can result in weight gain and ankle swelling. Also, waste materials will not be filtered out of the blood any longer.
The tiny filters in the kidneys are damaged and the kidneys can slowly fail. If permanent kidney failure develops this would be fatal unless the affected person receives a kidney transplant or long term dialysis treatment.