The kidneys are vital organs. They are responsible for the removal of waste products from the body, the regulation of body fluids and the production of some hormones. When kidneys can no longer perform these functions at sufficient capacity, the result is kidney disease, also called renal failure. Usually, renal failure occurs as the result of a gradual decrease in the efficiency of the kidneys over a long period (chronic renal failure). Many conditions can lead to chronic renal failure; the most frequent include diabetes, chronic kidney inflammation, high blood pressure and vascular damage. In some cases it is the consequence of sudden kidney failure, i.e. acute renal failure.