Diagnosis- Exams and Tests

When a person is diagnosed with diabetic nephropathy, they should have a urine test at least once a year. Urine tests look for a protein called albumin, this test is also called a microalbuminuria test because it looks for small amounts of albumin. Having too much protein in the urine is a sign of kidney damage. Because high blood pressure is often associated with diabetic nephropathy; tests for high blood pressure may be done.

Every year doctors may also check the kidneys with blood tests such as BUN, and serum creatinine test. A blood urea nitrogen (BUN) test measures the amount of urea nitrogen in the blood. Urea is a chemical waste product that travels from the liver to the kidneys through the bloodstream. Normal kidneys filter urea and other waste products from the blood and take it out of the body as urine. If a BUN test shows that the urea nitrogen levels of a person are higher than normal that could mean that the kidneys aren’t functioning properly.

A creatinine test measures the level of creatinine in the blood and gives an estimate of how well the kidneys are filtering, and also measures creatinine in the urine. Creatinine is a chemical waste product that's produced by a person’s muscle metabolism; healthy kidneys filter creatinine and other waste products from the blood and exit them through urine. If the kidneys are not working properly a high level of creatinine may build in the blood. Kidney biopsies can determine if a person does or does not have the disease, but is only done if there is doubt about the diagnosis. This is done by removing a sample of tissue from a kidney, this may be the most accurate test, but it is not recommended if results of an ultrasound examination show that the kidneys are small and scarred.

A 24-hour urine protein test is done to measure the amount of protein found in urine over a period of 24 hours. This is a 2 day process where on the 1^st day one must urinate into a toilet in the morning and collect all the urine in a special container for the next 24 hours. On the 2^nd after waking up one must urinate in the container, the seal the container and refrigerate it. Normal results must have less than 80 milligrams per day, or less than 10 milligrams per deciliter of urine. Ultrasonography is done to check the size of the kidneys, when the results show a small, scarred kidney that often indicates that the kidney failure is chronic. A protein electrophoresis test estimates how much protein one has in their urine. To get a urine sample males need to wipe clean the head of the penis, and females need to wash the area between the lips of the vagina with soapy water and then rinse. Then both males and females should allow a small amount of urine to fall into the toilet then in a clean container catch about 1 to 2 ounces of urine. Normal results should show no significant amount of globulins in the urine and urine albumin should be less than 5 mg/dL.