Dual energy x-ray absorptiometry (DEXA) scan: a test that uses low energy x-rays to measure the mineral content of bones. A DEXA scan uses less radiation than a standard chest x-ray.
Magnetic resonance imaging (MRI): a way to take pictures of the inside of the body. MRI uses magnetic fields and radio waves instead of x-rays. MRIs are particularly useful for taking pictures of the body's soft tissues and organs.
Protease inhibitor (PI): class of anti-HIV medication. PIs work by blocking protease, a protein that HIV needs to make copies of itself. The PIs approved by the FDA are Agenerase, Aptivus, Crixivan, Fortovase, Invirase, Kaletra, Lexiva, Norvir, Reyataz, and Viracept.
What is osteonecrosis, and what are its symptoms?
Osteonecrosis means "bone death." Bone can die if its blood supply is cut off and it can't get nutrients; this is called avascular necrosis. Osteonecrosis occurs in the hip bones of some people with HIV, but doctors aren't sure why. It is not clear if osteonecrosis occurs because of HIV infection itself or as a side effect of the medications used to treat HIV.
Symptoms of osteonecrosis include:
How is osteonecrosis diagnosed?
If you have symptoms of osteonecrosis, early diagnosis is best made by magnetic resonance imaging (MRI) of the bone. MRI is able to detect osteonecrosis before bone is significantly damaged and before abnormalities can be seen on an x-ray. X-rays and CT scans may also be used to look for osteonecrotic bone damage.
What is the treatment for osteonecrosis?
While some treatments may provide relief from the pain associated with osteonecrosis, surgical removal of the dead bone and joint replacement are the only effective treatments for people who have serious osteonecrosis. If you have osteonecrosis, you may benefit from:
What are osteopenia and osteoporosis, and what are their symptoms?
Bones are made of minerals like calcium and phosphate. Osteopenia is a condition in which the bones lose these minerals and become less dense. This makes the bones weaker. When bone loss becomes more severe, the condition is referred to as osteoporosis.
There are no obvious symptoms in the early stages of osteopenia and osteoporosis. However, fractures may occur if bone loss continues. The most common fractures involve the spine, wrists, or hips. Fractures may cause:
Who is at risk of developing osteopenia and osteoporosis?
Anyone can develop osteopenia and osteoporosis. You may be at increased risk if you take HIV protease inhibitors (PIs). You may also be at increased risk if you:
Anti-HIV medications can cause negative side effects that may increase your risk of osteopenia and osteoporosis. These side effects include:
How are osteopenia and osteoporosis diagnosed?
A dual energy x-ray absorptiometry (DEXA) scan is used to diagnose osteopenia and osteoporosis. A DEXA scan is a painless, noninvasive procedure to determine your bone mineral density. Your bone density is then compared to people of your age and health to determine if your bones are weaker than they should be.
Although there are currently no specific guidelines for how often HIV positive people should have a DEXA scan, you should talk with your doctor about your risk factors for osteopenia and osteoporosis.
What are the treatments for osteopenia and osteoporosis?
If you have osteopenia or osteoporosis, you may benefit from:
How can I prevent bone disorders from occurring?
Some things you can do to lower your risk of bone problems:
Contact your doctor or an AIDSinfo Health Information Specialist at 1-800-448-0440 or http://aidsinfo.nih.gov.
This information is based on the U.S. Department of Health and Human Services' Guidelines for the Use of Antiretroviral Agents in HIV-1-Infected Adults and Adolescents (available at www.aidsinfo.nih.gov/Guidelines/).