Kidneys are essential to maintain the fluid balance in the body and control the body's chemistry. Kidney failure leads to a build-up of fluid and an increase in waste products in the blood stream. One serious side effect is an elevation in the body's potassium level which can lead to life threatening heart arrhythmias and death. There are many causes of this disorder with diabetes and high blood pressure being the most common. Unfortunately symptoms are usually not experienced until over 90% of the kidney function has been lost. This is why it is important for patients with high blood pressure and diabetes to have frequent medical check-ups.