Ankylosing spondylitis (AS) is a type of arthritis that affects the spine. "Ankylosing" means stiff or rigid, "spondyl" means spine, and "itis" refers to inflammation. The disease causes inflammation of the spine and large joints, resulting in stiffness and pain. The disease may result in erosion at the joint between the spine and the hip bone (the sacroiliac joint), and the formation of bony bridges between vertebrae in the spine, fusing those bones. In addition, bones in the chest may fuse.
The cause of AS is unknown, although researchers suspect genetics play a role. A gene called HLA-B27 occurs in over 95 percent of those with AS. However, some people with the HLA-B27 gene do not have AS.
AS is more common among young people, ages 17 to 35, but it can occur in children and older adults as well. The disease affects two to three times more young men than women and it tends to run in families.
Symptoms of AS tend to occur and disappear over periods of time. The following are the most common symptoms of AS. However each individual may experience symptoms differently. Symptoms may include:
• Back pain, usually most severe at night during rest
• Early morning stiffness
• Stooped posture in response to back pain (bending forward tends to relieve the pain)
• Straight and stiff spine
• Inability to take a deep breath, if the joints between the ribs and spine are affected
• Appetite loss
• Weight loss
• Joint pain
• Mild eye inflammation
• Organ damage, such as the heart, lungs, and eyes
The symptoms of ankylosing spondylitis may resemble other medical conditions or problems. Always consult your physician for a diagnosis.