In this article, we highlight a recent NEJM review that addresses the difference between axial spondyloarthritis and ankylosing spondylitis.
Axial spondyloarthritis, of which ankylosing spondylitis is a subset, is thought to be about as prevalent in the U.S. as rheumatoid arthritis, affecting from 0.9 percent to 1.4 percent of the adult population.
While rheumatologists generally diagnose and know how to specifically treat axial spondyloarthritis, patients often experience long delays in diagnosis, in part, because non-rheumatologists don’t recognize the chronic condition, according to a review published June 30 in the New England Journal of Medicine.
Researchers from the University of Texas Southwestern Medical Center in Dallas, and National Institutes of Health, wrote this review to enhance axial spondyloarthritis and ankylosing spondylitis awareness and understanding.
“A high index of suspicion and clinical acumen are often needed to diagnose axial spondylitis and to prevent misdiagnosis,” the authors write. “No single clinical feature, laboratory test or imaging result is either necessary or sufficient for the diagnosis.”
Clinicians who encounter especially adolescents or young adults with unexplained back pain for more than three months should consider referring those patients to a rheumatologist, according to the authors.
They point out that inflammatory back pain is the most typical spondyloarthritis symptom. Seventy to 80 percent of ankylosing spondylitis patients have inflammatory back pain.
One of the more prominent features of this pain is back stiffness in the morning, which diminishes with activity and returns with inactivity.
In patients with chest pain, axial spondyloarthritis should be considered.
Goals in treatment are to improve and maintain spinal flexibility and normal posture, reduce functional limitations, maintain ability to work and decrease disease complications, according to the authors.
Patients should exercise to help maintain posture and range of motion, whether their spondyloarthritis is active or stable.
Nonsteroidal antiinflammatory drugs (NSAIDs) are the first-line medication for pain and stiffness. But when NSAIDs don’t work adequately to control symptoms, use of TNF inhibitors, including infliximab, etanercept, adalimumab, golimumab and certolizumab, have been shown in 13 randomized controlled trials and open label studies to result in a rapid and sustained improvement in objective and subjective indicators of disease activity and function. Patients who tend to do best on TNF inhibitors are younger with a shorter disease duration, high baseline of inflammatory markers and a low baseline of functional disability. But others may benefit from TNF inhibitors, too.
There is promising research in the use of medications that target the interleukin-23-interleukin-17 pathway, but more studies need to be done using these drugs to treat spondyloarthritis.
Taurog JD, Chhabra A, Colbert RA. “Ankylosing Spondylitis and Axial Spondyloarthritis,” New England Journal of Medicine. June 30, 2016. DOI: 10.1056/NEJMra1406182.