Avoiding Misdiagnosis of Axial Spondyloarthritis
MAY 21, 2020
Sergio Schwartzman, MD: What about commenting a little bit more on rheumatologists and their understanding of this disease? I'll switch this to Atul because he wrote a paper on this. Do you believe now, with over a decade of the concept of non-radiographic axial spondyloarthritis [SpA] being published and disseminated among the rheumatology community, that rheumatologists are still missing the diagnosis of non-radiographic axial SpA?
Atul Deodhar, MD, MRCP: I'm sure that they are still mixing up the diagnosis of non-radiographic axial spondyloarthritis. There has definitely been much more understanding of this condition. SPARTAN, the Spondyloarthritis Research and Treatment Network, along with GRAPPA, the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis, have conducted about 30 to 35 educational symposia all around the country.
It's also become an important issue in our board examinations. The junior faculty, or the fellows, are definitely learning about non-radiographic axial spondyloarthritis and radiographic axial spondyloarthritis in their fellowship. The American College of Rheumatology has become more aware of this. There are symposia held, because there are more drugs coming out in the market to treat this condition, that has sensitized rheumatologists.
Despite all of this, I still see patients being missed in terms of getting diagnosed with axial spondyloarthritis by rheumatologists. Philip and I were involved in a trial called PROSpA. There was no drug involved, and we were looking at the prevalence of axial spondyloarthritis in patients referred to rheumatologists with back pain. Interestingly, we found that 47% of patients who participated in the trial were existing patients of rheumatologists.
They were existing patients of rheumatologists, and they were going for backache, presumably. When the trial came along, rheumatologists started to find patients to enroll into the trial, and they found some of the patients in their own database. About 47% of the patients in that trial came from rheumatology practices, and several of those, about half of those, had axial spondyloarthritis.
So rheumatologists are definitely missing the diagnosis of non-radiographic axial spondyloarthritis. And I want to briefly add here that we are now also seeing that there is excessive diagnosis, or perhaps false positive diagnoses, of axial spondyloarthritis by rheumatologists because of the feeling that MRI [magnetic resonance imaging] “positivity” gets you the diagnosis of axial spondyloarthritis. This is as we do more MRIs on those who stay active, including athletes, as well as even simple degenerative changes in the spine and in the sacroiliac joint. All of those can have features that we generally call active or positive MRI.
That is, on the stored image, there is bone marrow edema. So it's both ways. There are patients being missed in terms of disease diagnosis as well as patients being determined to have axial spondyloarthritis when they may not actually have the disease. Philip was making this point, and I agree, that there is large value for educating rheumatologists not only so that they don’t miss diagnosing these patients, but also so they don’t incorrectly diagnose patients who do not have this disease.
Sergio Schwartzman, MD: The need for better diagnostic tools.
Transcript Edited for Clarity