Don’t skip specialist for possible AS

DEAR DR. ROACH: My significant other and I are debating whether I should pursue follow-up testing with a rheumatologist for the possibility of ankylosing spondylitis. I say no, and she says yes, because things could be worse down the road if I do have AS and don’t deal with it starting now.

I am in my mid-60s, 45 years with iritis (almost annually treated with prep forte) and in the past year was positive on an HLA-B27 test. My lumbar spine X-ray impression was “mild lumbar spondylosis,” but not fusion (as is often seen with AS). My lower-back and hip pain and stiffness generally are worse in the morning and get better with activity and as-needed Advil. My primary care physician gave me an option to refer out to a rheumatologist for follow-up.

My feeling is that it would be an unnecessary expense and time. I’m doubtful of an AS diagnosis, and even if diagnosed, it’s not really worth treating at this point. My significant other disagrees. What would you recommend? – B.B.

ANSWER: I agree with your significant other, without hesitation.

Ankylosing spondylitis is an inflammatory type of arthritis whose major symptom is lower-back pain, but one which can affect other joints and other parts of the body, including skin, gut and eye. The abnormalities usually show up on X-ray but sometimes do not.

Making the diagnosis of ankylosing spondylitis (physicians often abbreviate this verbally as the somewhat uncouth “ank spon”) isn’t always straightforward. Chronic back pain at an early age is suggestive. The genetic test you had, HLA-B27, is positive in 90 percent or so of people with AS but only 8 percent of the general population. Still, even most people with back pain and who are HLA-B27 positive do not have AS.

A careful interpretation of the spine film results is necessary by an experienced radiologist who can grade the sacroiliac joint; this is critical in helping to support or reject a diagnosis of AS.

Iritis, inflammation of the iris, is more consistent with a different inflammatory joint disease called reactive arthritis. With AS, the eye disease is typically uveitis. Although it’s possible the eye doctor used the term imprecisely.

The reason I think a rheumatologist is essential in this disease is that the condition should be recognized as early as possible so that proper treatment may be begun. You may be right that no more than ibuprofen is necessary.