Kidney disease tests
Several tests can be performed to determine if you are suffering from kidney disease.
Chronic kidney disease may be a serious complication for those who have Type 2 diabetes. If you have Type 2 diabetes your doctor will use one or more tests to determine whether or not you have kidney disease. Some of the tests may be performed on an ongoing basis to monitor the health of your kidneys.
Blood tests are used to measure the level of waste products, such as creatinine and urea, in your blood. Creatinine is a chemical waste product that is typically filtered out of your blood by your kidneys. The test used is called a serum creatinine test. The Blood Urea Nitrogen (BUN) test measures how well the kidneys are working to filter urea (another chemical waste product) from the blood. If there are elevated levels of creatinine and/or urea in the blood it is an indication that there may be a problem with the kidney function.
Urine tests are also used to reveal issues that may be associated with chronic kidney disease. The urine microalbumin test can detect minute levels of a blood protein, called albumin in the urine. The test is used to detect early signs of kidney damage in people who are at risk of developing kidney disease. If the kidneys are not filtering properly, healthy substances, such as proteins will leak through your kidneys and leave your body through your urine. Albumin is one of the first proteins to leak out when kidneys are damaged. For those with diabetes it is recommended that the microalbumin test be done at least once per year.
Imaging tests are used to look at the kidney’s structure and size. Imaging refers to any technique that takes images, or pictures of the bones and organs inside the body. Ultrasound is one example. Ultrasound uses sound wave technology to determine the size and shape of the kidneys and it may also be used to assess blood flow to the kidneys. A computed tomography (CT or CAT) scan is another type of imaging test that uses X-ray and computer technology to show detailed images of the kidneys (and other organs). It is much more detailed than a typical X-ray.
Another test that may be used to determine kidney function in some cases is a biopsy. In a biopsy, a sample of the kidney tissue is removed for testing to determine what may be causing the kidney problem. For a person who has chronic kidney disease, a biopsy can tell a doctor how quickly the disease is progressing. A biopsy is usually done with a needle. In an open biopsy a sample of the kidney is taken during surgery. Biopsies are done for various reasons. Your doctor may want a biopsy conducted if there is blood in your urine, or if there is an abnormal blood test result. A biopsy may help a physician determine whether treatment is actually helping, or if the disease is getting worse.
Talk with your doctor about the most appropriate test(s) for you, and be sure to ask how often they should be done. You can find more information about chronic kidney disease through the National Kidney Foundation and the Centers for Disease Control and Prevention.
Michigan State University Extension provides education in chronic disease prevention and management. To contact an expert in your area visit http://expert.msue.msu.edu or call 888-MSUE4MI (888-678-3464).