Neal Birnbaum, MD, on Nonradiographic Axial Spondyloarthritis: Part 2

In part 2 of this podcast, Dr Birnbaum discusses the therapeutic options for treating nonradiographic spondyloarthritis and how to best monitor patients for progression of disease.

Neal Birnbaum, MD, is chief of rheumatology at California Pacific Medical Center in San Francisco, California.

TRANSCRIPT:

Welcome to this podcast from the Rheumatology and Arthritis Learning Network. I'm your moderator, Rebecca Mashaw. Today I'm continuing my conversation about nonradiologic axial spondyloarthritis with Dr. Neil Birnbaum Chief of Rheumatology at California Pacific Medical Center in San Francisco. Today, Dr. Birnbaum is going to discuss therapy for this condition and how to monitor patients over time.

RALN:

Are there differences in the therapies for these conditions?

Dr Birnbaum:

Between radiographic and nonradiographic? Not really. The patient normally is going to be tried on very simple things. First, a nice hot shower in the morning, stretching exercises, and nonsteroidal anti-inflammatories, the classic one being indomethacin and there's an indomethacin SR, 75 milligrams sustained release, that given at dinner, often carries through the night to help the morning stiffness. That's not the only one that can be used.

For patients who do not respond adequately to nonsteroidal anti-inflammatories, we now know that the traditional DMARDs, disease modifying drugs, that are used often in rheumatoid arthritis, such as hydroxychloroquine and methotrexate, don't really work well in spinal disease, whether it's radiographic or nonradiographic. In those patients, we go then to a biologic therapy and these are usually going to be anti-TNF biologics. My experience has been that anti-TNFs work extremely well in spondylitis, whether they're radiographic or nonradiographic.

I would also add that if a patient who we suspect has AS, and we haven't been able to document it, sometimes we'll do a therapeutic trial of an anti-TNF. That's a way of taking that patient where you've done everything and you're not sure whether they really qualify as nonradiographic X1, they sound like it, but you haven't been able to prove it, giving them a trial of a TNF, a 90 day-trial is another way of saying yes, I think this patient has nonradiographic spondyloarthropathy.

RALN:

What about assessing progression of disease? And what about the concept that nonradiographic axial spondyloarthritis may be an early stage of eventual ankylosing spondylitis?

Dr Birnbaum:

Yeah. Well, as I said before, in my mind, it's not a concept. It's the reality that if you follow these patients long enough, we know that can be a dozen years between the onset of symptoms and development of plain x-ray change. A certain number of patients every year will go on to develop x-ray change, but you may need to follow them a long time—particularly women, who tend to show less severe disease and spondylitis, so that progression may be more difficult, making the diagnosis more subtle. Therefore, you have to really remember that HLA-B27 is not an X or Y linked gene. It's a 6-chromosome gene. Therefore, the incidence is the same in men and women. And the overall rate of spondylitis is the same, but the expression, the penetrance, is different, so that women very often will have much more subtle disease than men.

RALN:

So how do you assess progression then if you're waiting for years to see any kind of changes on imaging? Is that where the MRI comes in?

Dr Birnbaum:

It can. Or you could periodically do plain x-rays and see if there's a change over time. I don't know that that's terribly important because what we're really thinking about is treatment, relief of symptoms. In rheumatoid arthritis, it's pretty much the assumption that if you put that patient into a clinical remission, that they're not having a lot of progression of x-ray change. I think the same can be said in spondylitis, that if I take this young guy, who's got classic disease, he's B27 positive, and I treat him and he calls me a month later, tells me what a wonderful doctor I am because I put him on an anti-TNF. If his symptoms remain well controlled, if he remains in remission, the likelihood of him progressing and fusing is extremely low.

RALN:

What about the biomarkers? You mentioned sed rate earlier, C-reactive protein, are those things that you would check on a regular basis with these patients?

Dr Birnbaum:

Yes. If those are elevated at the time of diagnosis, then they can be used along with the clinical response to assess disease activity and response to treatment. And under management, the major thing is, are the patient's symptoms better. Many times they're dramatically better. In that situation, that's what you're looking for.

RALN:

Right.

Dr Birnbaum:

The use of plain x-ray to assess progression is difficult, because it progresses very slowly. The use of MRI has been somewhat controversial because the changes, sometimes they're there, sometimes they're not. They're not consistent, they're some variability in the reading of those by the radiologist. So I think they're helpful in making the initial diagnosis of nonradiographic axial spondyloarthropathy, but they're not as good at following the activity of the disease. The other thing, obviously, is that the patient has changes on plain x-ray of the sacroiliac joints. You don't need an expensive MRI.

RALN:

Do you have any final thoughts you would like to share with your rheumatology colleagues who may be dealing with patients who have some of the symptoms? And what they need to do to get a firm diagnosis and then to devise a treatment plan?

Dr Birnbaum:

I think we've all come to learn that spinal arthroses are quite common and that we need to be educating our primary care doctors, our chiropractors, our spine orthopedists, to think about inflammatory disease. And for them to realize that some of those patients will have subtle disease,. Some of them will have a story of inflammatory back pain, but won't yet have plain x-ray changes. I think for rheumatologists, we're now pretty well up on spondylitis. We're doing pretty well in accepting the fact there's a spectrum of disease that goes from patients with symptoms and no plain x-ray change to those who, when they come in the office, already have few sacroiliac joints. But all of those patients can be dramatically helped by the current biologic therapies.

RALN:

Okay. Well thank you very much for your time this afternoon.