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If it is not well controlled, type 1 diabetes can cause high blood glucose levels, which can force your kidneys to work harder to do this filtering. The capillaries become more porous and start to leak. Proteins that should normally not be filtered out start to appear in your urine.
People with type 1 diabetes sometimes develop little holes in the filtering devices in their kidneys so they start to spill small amounts of protein, called proteinuria," says Jay Cohen, MD, medical director of the Endocrine Clinic in Memphis and clinical assistant professor of family medicine at the University of Tennessee.
"If there is uncontrolled diabetes on top of the proteinuria," says Dr. Cohen, "that can lead to a difficulty of the kidneys being able to get rid of a poison in your blood called creatinine." Cohen says that creatinine can build up in your blood, which puts you at risk of kidney failure