Nellis Family Medicine Residency, Las Vegas, Nev (Drs. Covey and Church); Uniformed Services University of the Health Sciences, Las Vegas, Nev (Dr. Covey) carlton.j.covey.mil@mail.mil
The authors reported no potential conflict of interest relevant to this article.
The opinions and assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the US Air Force Medical Department or the US Air Force at large.
HLA-B27 is positive in 70% to 95% of patients with axSpA and can help build a case for the disorder.6,12 CRP is useful too, as an elevated CRP has important treatment implications (more on that in a bit).6
Other diagnoses in the differential include: degenerative disc disease, lumbar spondylosis, congenital vertebral anomalies, and osteoarthritis of the SI joint, bone metastasis, or primary bone tumors.1
Start with plain x-rays.The American College of Radiology (ACR) published appropriateness criteria for obtaining x-rays in patients suspected of having axSpA.13 Plain x-rays of the spine and SI joint are recommended for the initial evaluation. Magnetic resonance imaging (MRI) of the SI joint and/or spine should be obtained if the initial x-rays are negative or equivocal. Patient symptomology and/or exam findings determine whether to include the SI joint and/or spine. If the patient has subjective and objective findings concerning for pathology of both, then an MRI of the spine and SI joint is warranted.
HLA-B27 is positive in 70%-95% of patients with axSpA.
Alternatively, computed tomography (CT) can be substituted if MRI is unavailable. In patients with known axSpA, surveillance radiography should not occur more often than every 2 years.6
Timely referral is essential
Timely referral to a rheumatologist is an essential part of early diagnosis and treatment. Advances in treatment options for axSpA have become available in recent years and offer new hope for patients.
