Ankylosing Spondylitis
Also called rheumatoid spondylitis or Marie-Strümpell disease, ankylosing spondylitis primarily affects the sacroiliac, the axial spine, and the adjacent ligamentous
or tendinous attachments to the bone. Sometimes large synovial joints, such as the hips, knees, and shoulders, can be affected.
or tendinous attachments to the bone. Sometimes large synovial joints, such as the hips, knees, and shoulders, can be affected.
Gender differencesAnkylosing spondylitis in females
Progressive ankylosing spondylitis is more common in males than in females and is therefore often overlooked in female patients. Misdiagnosis is further compounded by its presentation: Because joints away from the spine are more commonly affected in female patients, the condition is usually attributed to back pain or injury.
Secondary ankylosing spondylitis may be associated with reactive arteritis (Reiter’s syndrome), psoriatic arteritis, or inflammatory bowel disease. These disorders, together with primary ankylosing spondylitis, are usually classified as seronegative spondyloarthropathies.
Typically beginning in adults before age 40, this inflammatory disease progressively restricts spinal movement. It begins in the sacroiliac and gradually progresses to the lumbar, thoracic, and cervical spine. Bone and cartilage deterioration leads to fibrous tissue formation and eventual fusion of the spine or the peripheral joints. Symptoms progress unpredictably into remission, exacerbation, or arrest at any stage.
Ankylosing spondylitis usually occurs as a primary disorder, but it also may occur secondary to various GI, genitourinary (GU), and cutaneous disorders. For example, with GI disease, ankylosing spondylitis may occur in association with ulcerative colitis, regional enteritis, Whipple’s disease, gram-negative dysentery, and yersiniosis. With GU disease, it’s associated with chlamydial or mycoplasmic infections, and with cutaneous disease, it’s associated with psoriasis, acne conglobata, and hidradenitis suppurativa.
In primary disease, sacroiliitis is usually bilateral and symmetrical; in secondary disease, it’s usually unilateral and asymmetrical. The patient may also have extra-articular disease, such as acute anterior iritis (about 25% of patients), proximal root aortitis and heart block, and apical pulmonary fibrosis. Rarely, extra-articular disease appears as caudal adhesive leptomeningitis and immunoglobulin (Ig) A nephropathy.
Ankylosing spondylitis affects males three to four times more often than females. Progressive disease is well recognized in males but often overlooked or missed in females. (See Ankylosing spondylitis in females.)
Causes
Studies suggest a familial tendency for ankylosing spondylitis; however, the exact cause of the disease is unknown. In more than 90% of the patients with this disease, circulating immune complexes and human leukocyte-histocompatibility antigen (HLA-B27) suggest immune system activity.
Complications
Rarely, disease progression can impose severe physical restrictions on activities of daily living and occupational functions. Atlantoaxial subluxation is a rare complication of primary ankylosing spondylitis. Sometimes, there is severe ankylosis of the spine, which can cause respiratory complications.
