Ankylosing Spondylitis - Signs and Symptoms

Signs and Symptoms

The typical patient is a young male, aged 20–40; however, the condition also presents in females. The condition is known to be hereditary. Symptoms of the disease first appear, on average, at age 23 years. These first symptoms are typically chronic pain and stiffness in the middle part of the spine or sometimes the entire spine, often with pain referred to one or other buttock or the back of thigh from the sacroiliac joint.

Symptoms appear gradually. Initially they are usually not specific for ankylosing spondylitis. The average onset-to-diagnosis lag time has been estimated to be approximately 8.5 years to 11.4 years.

Men are affected more than women by a ratio of about 3:1, with the disease usually taking a more severe course in men than women.

In 40% of cases, ankylosing spondylitis is associated with an inflammation of the eye (iritis and uveitis), causing redness, eye pain, vision loss, floaters and photophobia. This is thought to be due to the association these two conditions have with inheritance of HLA-B27. Other common symptoms are generalized fatigue and sometimes nausea. Less commonly, aortitis, apical lung fibrosis and ectasia of the sacral nerve root sheaths may occur.

When the condition presents before the age of 18, it is relatively likely to cause pain and swelling of large limb joints, particularly the knee. In prepubescent cases, pain and swelling may also manifest in the ankles and feet, where calcaneal spurs may also develop.

Pain is often severe at rest, but improves with physical activity. However, many experience inflammation and pain to varying degrees regardless of rest and movement.

Ankylosing spondylitis is one of a cluster of conditions known as seronegative spondyloarthropathies, in which rheumatoid factor tests are negative and the characteristic pathological lesion is an inflammation of the enthesis (the insertion of tensile connective tissue into bone).