Renal failure, especially CRF (Chronic renal failure), is a fairly common condition in older cats and dogs. The kidneys become less and less efficient at removing wastes from the blood. CRF can sometimes be mistaken for diabetes, since polyuria and polydipsia can occur in both; this may lead to incorrect treatment and progression of the renal failure. When CRF occurs in a diabetic pet, things can get tricky, since diabetes and CRF can complicate each other: See also urination, renal threshold, low-carb diet, medium-carb diet, urinary tract infection, kidney infection.