Ankylosing spondylitis

Alternative names:

Marie-Strumpell disease; rheumatoid spondylitis; spondylitis

Definition:

Spondylitis involves inflammation of one or more vertebrae. Ankylosing spondylitis is a chronic inflammatory disease that affects the joints between the vertebrae of the spine, and the joints between the spine and the pelvis. It eventually causes the affected vertebrae to fuse or grow together. (See also tuberculosis and arthritis).

Causes, incidence, and risk factors:

The specific cause for this disease is unknown, but genetic factors seem to play a role. The disease starts with intermittent hip and/or lower back pain that is worse at night or after inactivity. Back pain begins in the sacroiliac joint (joint between the pelvis and the spine) and may progress to include the lumbosacral spine and the thoracic spine (chest portion of the spine). Pain may be eased by assuming a bent posture. Limited expansion of the chest occurs because of the involvement of the joints between the ribs. The symptoms may worsen, go into remission, or stop at any stage.

With progressive disease, deterioration of bone and cartilage can lead to fusion in the spine or peripheral joints affecting mobility. It can be extremely painful and crippling. The heart, the lungs, and the eyes may also become affected. The disease most frequently begins between the ages of 20 and 40 but may begin before 10 years of age. It affects more males than females. Risk factors include a family history of ankylosing spondylitis and male gender. The incidence is 1 out of 10,000 people.