November 29, 2015
font size

Ankylosing Spondylitis

Medical Author:
Medical Editor:

Ankylosing spondylitis facts

  • Ankylosing spondylitis belongs to a group of arthritis conditions that tend to cause chronic inflammation of the spine (spondyloarthropathies).
  • Ankylosing spondylitis affects males two to three times more commonly than females.
  • Ankylosing spondylitis is a cause of back pain in adolescents and young adults.
  • The tendency to develop ankylosing spondylitis is genetically inherited.
  • The HLA-B27 gene can be detected in the blood of most patients with ankylosing spondylitis.
  • Ankylosing spondylitis can also affect the eyes, heart, lungs, and occasionally the kidneys.
  • The optimal treatment of ankylosing spondylitis involves medications that reduce inflammation or suppress immunity, physical therapy, and exercise.

What is ankylosing spondylitis?

Ankylosing spondylitis is a form of chronic inflammation of the spine and the sacroiliac joints. The sacroiliac joints are located at the base of the low back where the sacrum (the bone directly above the tailbone) meets the iliac bones (bones on either side of the upper buttocks) of the pelvis. Chronic inflammation in these areas causes pain and stiffness in and around the spine, including the neck and back. Over time, chronic inflammation of the spine (spondylitis) can lead to a complete cementing together (fusion) of the vertebrae, a process referred to as ankylosis. Ankylosis causes loss of mobility of the spine.

Inflammation of Spondyloarthropathy Illustration - Picture of Ankylosing Spondylitis
Picture of areas of inflammation in ankylosing spondylitis inflammation

Ankylosing spondylitis is also a systemic disease, meaning it can affect tissues throughout the body, not just the spine. Accordingly, it can cause inflammation in and injury to other joints away from the spine manifest as arthritis, as well as to other organs, such as the eyes, heart, lungs, and kidneys. Ankylosing spondylitis shares many features with several other arthritis conditions, such as psoriatic arthritis, reactive arthritis (formerly called Reiter's disease), and arthritis associated with Crohn's disease and ulcerative colitis. Each of these arthritic conditions can cause disease and inflammation in the spine, other joints, eyes, skin, mouth, and various organs. In view of their similarities and tendency to cause inflammation of the spine, these conditions are collectively referred to as "spondyloarthropathies." Ankylosing spondylitis is considered one of the many rheumatic diseases because it can cause symptoms involving muscles and joints.

Ankylosing spondylitis is two to three times more common in men than in women. In women, joints away from the spine are more frequently affected than in men. Ankylosing spondylitis affects all age groups, including children. When it affects children, it is referred to as juvenile ankylosing spondylitis. The most common age of onset of symptoms is in the second and third decades of life. Ankylosing spondylitis is often abbreviated AS and has been referred to as Bechterew's disease.

Medically Reviewed by a Doctor on 7/17/2015


Women's Health

Find out what women really need.

Use Pill Finder Find it Now See Interactions

Pill Identifier on RxList

  • quick, easy,
    pill identification

Find a Local Pharmacy

  • including 24 hour, pharmacies

Interaction Checker

  • Check potential drug interactions
Search the Medical Dictionary for Health Definitions & Medical Abbreviations