Kidney disease usually affects both kidneys. If the kidneys' ability to filter the blood is seriously damaged by disease, wastes and excess fluid may build up in the body.

Although many forms of kidney disease do not produce symptoms until late in the course of the disease, there are six warning signs of kidney disease:

1. High blood pressure.

2. Blood and/or protein in the urine.

3. A creatinine and Blood Urea Nitrogen (BUN) blood test, outside the normal range. BUN and creatinine are waste that build up in your blood when your kidney function is reduced.

4. A glomerular filtration rate (GFR) less than 60. GFR is a measure of kidney function.

5. More frequent urination, particularly at night; difficult or painful urination.

6. Puffiness around eyes, swelling of hands and feet.