Diagnosis of axial spondyloarthritis includes ankylosing spondylitis and non-radiographic axial spondylitis arthritis, based on the presence of sacroiliitis on MRI or plain radiography and at least one spondyloarthritis feature or HLA -B 27 positivity, and at least two spondyloarthritis features.
Usually occurs in the second or third decade of life, with less than 5% of patients diagnosed when older than 45 years of age.
The pain is inflammatory as suggested by: improvement with exercise, pain at night, insidious onset of pain, aged onset younger than 40 years, and no improvement with rest.
If at least four of the five criteria are identified, it has a sensitivity of 79.6% and a specificity of 72.4% in diagnosing inflammatory back pain.
In a patient with at least three months of inflammatory back pain, plain x-rays may show sacroiliitis with a sensitivity of 48%.
T-weighted MRI of the pelvis or symptomatic spinal area can show sacroiliitis or spondylitis with the sensitivity of 85%.
Nonsteroidal anti-inflammatory drugs are the mainstay of treatment.
Other biologic agents such as antitumor necrosis factor alpha may be employed.
Sulfasalazine is commonly utilized, especially for patients with peripheral arthritis, although its role in management has not been clinically demonstrated.