If you have diabetes, your blood glucose, or blood sugar, levels are too high. Over time, this can damage your kidneys. Your kidneys clean your blood. If they are damaged, waste and fluids build up in your blood instead of leaving your body. Kidney damage from diabetes is called diabetic nephropathy. It begins long before you have symptoms. If the damage continues, your kidneys could fail.
Click here for more information. http://www.nlm.nih.gov/medlineplus/diabetickidneyproblems.html