Evaluation of Osteoporosis

Why are tests done for osteoporosis? If you have osteoporosis, low bone density, or unexplained bone fractures, tests can determine whether there are any undetected contributing problems, help in the selection of medication for treatment, find out whether you are responding to treatment as expected, or evaluate poor response to treatment.

What tests are usually done? A 24-hour urine collection can show if there is a problem with intestinal absorption of calcium or leakage of calcium through the kidneys. Blood tests are done to check things such as blood chemistries (to see if your calcium or phosphorous level is too high or too low, or if there is a problem with liver or kidney function), blood count (checking for anemia), proteins (to be sure there is no multiple myeloma), vitamin D level (a low level causes trouble with getting calcium to your bones), thyroid function (high thyroid function can cause osteoporosis), and antibodies for celiac disease- a condition that may cause poor intestinal absorption of important nutrients. A simple "fasting second-void morning urine" specimen shows the rate of bone metabolism or "turnover"- an important factor in determining bone density and bone strength. With this test, natural bone protein products such as N-telopeptide (NTX) are tested. X-rays may detect previous fractures of the spine, which can occur with or without back pain and may result in loss of height. Sometimes a nuclear bone scan can identify other kinds of bone disease that cause fractures. In rare cases, a bone biopsy provides helpful information. Other tests may be necessary depending on your particular situation.

How are the tests done? If a 24-hour urine collection is ordered, please go to the lab to get a container for the urine collection and carefully follow the instructions on the other side of this page.

If blood tests are ordered, you must have nothing to eat or drink (except water) after midnight, and be at the lab about 8:00 AM.

If a "fasting second-void morning urine" specimen for NTX is ordered, you must have nothing to eat or drink (except water) after midnight, and be at the lab about 8:00 AM. Urinate at home before you go to the lab, and plan on giving the lab a fresh urine specimen when you are there.

If all three types of tests are ordered, you may combine them in one of the following ways: a. When you give your 24-hour urine container to the lab at 8:00 AM, you can also have a fasting blood specimen drawn and give them a fresh urine specimen, or b. Go to the lab for a fasting blood test and second void urine specimen first, and they will then give you a container for doing the 24-hour urine collection later.

Page last updated: 08/18/08