Ankylosing spondylitis is a long-term disease that causes inflammation of the joints between the spinal bones, and the joints between the spine and pelvis. Eventually, the disease causes the affected spinal bones to join together.
The cause of ankylosing spondylitis is unknown, but genetics may play a role. The disease most often begins between ages 20 and 40, but may begin before age 10. It affects more males than females.
Ankylosing spondylitis starts with low back pain that comes and goes. Back pain may begin in the sacroiliac joints between the pelvis and the spine. Over time, it may involve all or part of the spine.
- Pain and stiffness that are worse at night, in the morning or when you are not active
- Pain that awakens you from sleep
- Pain that improves with activity or exercise
- Loss of motion or mobility in the lower spine
- Inability to fully expand your chest because the joints between the ribs are affected
Less common symptoms include:
- Eye inflammation or uveitis
- Heel pain
- Hip pain and stiffness
- Joint pain and joint swelling in the shoulders, knees and ankles
- Loss of appetite
- Slight fever
- Weight loss
Diagnostic tests may include:
- Complete blood count
- ESR or erythrocyte sedimentation rate, which measures inflammation in the body
- HLA-B27, called human leukocyte antigen B27, a blood test to look for a protein found on the surface of white blood cells
- X-rays of the spine and pelvis
- MRI of the spine
Your doctor may prescribe nonsteroidal anti-inflammatory drugs (NSAIDs) to reduce inflammation and pain. Physical therapy and exercises can help improve posture and breathing. Lying flat on the back at night can help maintain normal posture.
Corticosteroid therapy or medications to suppress the immune system may also be prescribed. Drugs called TNF-inhibitors (etanercept, adalimumab, infliximab), which block an inflammatory protein, have been shown to improve the symptoms of ankylosing spondylitis.
Some healthcare professionals use drugs that block cell growth (cytotoxic drugs) in people who do not respond well to corticosteroids or who are dependent on high doses of corticosteroids.
Surgery may be done if pain or joint damage is severe.
The course of ankylosing spondylitis is unpredictable. Symptoms may come and go at any time. Most people are able to function unless the hips are severely involved.
Source: National Institutes of Health