Home :: Ankylosing Spondylitis

Ankylosing Spondylitis

Alternative names :- Rheumatoid spondylitis; Spondylitis; Spondylarthropathy

A chronic, usually progressive inflammatory disease, ankylosing spondylitis (AS) primarily affects the sacroiliac, apophyseal, and costovertebral joints and adjacent soft tissue. Generally, the disease begins in the sacroiliac joints and gradually progresses to the lumbar, thoracic, and cervical regions of the spine. Deterioration of bone and cartilage can lead to fibrous tissue formation and eventual fusion of the spine or peripheral joints.

Prevalence of AS among whites is estimated at 0.5% to 1.0%, affecting five times as many males as females. Progressive disease is well recognized in men, but the diagnosis is often over­looked or missed in women, who tend to have more peripheral joint involvement. Secondary AS may be associated with reactive arthritis (Reiter's syndrome), psoriatic arthritis, or inflammatory bowel disease. These disorders, together with primary AS, are often classified as seronegative spondyloarthropathies.

Causes

Recent evidence strongly suggests a familial tendency in AS. The presence of histocompatibility antigen HLA-B27 (positive in over 90% of patients with this disease) and circulating immune complexes suggests immunologic activity. A possible link to underlying infection is being investigated.

Signs and symptoms

• low-back pain that is worse at night, in the morning, or after inactivity
• stiffness and limited motion in the low back
• hip pain and stiffness
• limited expansion of the chest
• loss of appetite
• weight loss
• eye inflammation
• neck pain
• heel pain

Diagnosis

Typical symptoms, a family history, and the presence of HLA-B27 strongly suggest AS. However, confirmation requires these characteristic X-ray findings:

• blurring of the bony margins of joints in the early stage
• bilateral sacroiliac involvement
• patchy sclerosis with superficial bony erosions
• eventual squaring of vertebral bodies .
• "bamboo spine" with complete ankylosis.

Erythrocyte sedimentation rate and alkaline phosphatase and creatine kinase levels may be slightly elevated. A negative rheumatoid factor helps rule out rheumatoid arthritis, which produces similar symptoms.

Treatment

Because AS's progression can't be stopped, treatment aims to delay further deformity by good posture, stretching and deep-breathing exercises and, in some patients, braces and lightweight supports. Patients must understand that a long-term daily exercise program is essential to delaying loss of function. Anti-inflammatory analgesics, such as aspirin, indomethacin, sulfasalazine, and sulindac, are given to control pain and inflammation.

Severe hip involvement usually necessitates surgical hip replacement. Severe spinal involvement may require a spinal wedge osteotomy to separate and reposition the vertebrae. This surgery is performed only on selected patients because of the risk of spinal cord damage and the long convalescence involved.

Special considerations

• AS can be an extremely painful and crippling disease, so the caregiver's main responsibility is to promote the patient's comfort while preserving as much mobility as possible. Keep in mind that his limited ROM makes simple tasks difficult. Offer support and reassurance.
• Administer medications as needed.
• Apply local heat and provide massage to relieve pain. Assess mobility and degree of discomfort frequently.
• Teach and assist with daily exercises as needed to maintain strength and function. Stress the importance of maintaining good posture.
• If treatment includes surgery, provide good postoperative care.
• Because AS is a chronic, progressively crippling condition, comprehensive treatment should also reflect counsel from a social worker, visiting nurse, and dietitian.