Ankylosing Spondylitis (AS)

What is ankylosing spondylitis (AS)?

Ankylosing spondylitis (AS) is a member of a group of diseases called spondyloarthropathies, which impacts about 3.5 to 13 in 1,000 people in the US. The easiest way to understand AS is to break down the words. “Ankylosing” comes from the word “ankylosis,” which is when the vertebrae in the back fuse together. “Spondylitis” is the inflammation between the joints in the pelvic bones and the joints at the base of the spine which extends between vertebrae. Simply, ankylosing spondylitis causes chronic inflammation in the spine, which can spread to the hips, shoulders, and sometimes the knees. When joints in the spine and ribs are affected, it’s harder for the chest to move and can make taking deep breaths difficult.

What are some of the symptoms of AS?

Not only does AS cause inflammation in the joints, but in almost 40-percent of people with AS, it causes inflammation in the eyes. This eye inflammation is called uveitis, and AS can sometimes cause a specific type called acute iritis, which affects the iris. If not resolved, uveitis can lead to vision loss, so the important symptoms to look out for are light sensitivity and eye pain. In rare cases, AS can impact the lungs, heart, and nervous system.

What causes AS?

Simply having family members (even parents) with AS does not mean a person will have it. Many environmental and genetic factors probably play a role in ankylosing spondylitis, and the majority of them are still unknown. One gene type, HLA-B, is a critical part of the immune system. HLA stands for human leukocyte antigen complex which helps the immune system figure out the body’s proteins from proteins created by viruses, bacteria, or other foreign bodies. The B cells are the instruction centers for creating many of the body’s proteins. Of the many types of HLA-B, HLA-B27 has been associated with AS, though having this variation doesn’t necessarily mean a person will have AS. Other genes, such as IL1A, ERAP1, and IL23R, are also linked with AS, but their interactions with AS are still being researched.

What treatment options are available for AS?

Once AS manifests, the symptoms can have a significant impact on daily life. Treating AS proactively may help stave off these effects and better prevent future complications. Medicines—including NSAIDS or biologics—play a huge role in this, but treatment is not limited to the pharmaceutical. Both an “ankylosing spondylitis diet” and a regular “ankylosing spondylitis exercise routine” that focuses on flexibility can go a long way in keeping the spine and joints protected.

Where can I find more information about ankylosing spondylitis?

• Spondylitis Association of America
• Medline Plus