Signs and symptoms
- Age < 45 years.
- Chronic back pain (3+ months).
- Morning stiffness (> 30 minutes).
- Improvement with exercise, not rest.
- Responds to anti-inflammatory medications.
- Night awakenings due to pain.
- Alternating buttock pain.
- Enthesitis and tendonitis.
- Swollen fingers or toes (dactylitis).
Aged under 45 years
AxSpA typically occurs in younger people, but it can be diagnosed at a later age, said Raj Sengupta, MBBS, a consultant rheumatologist and clinical lead for axSpA at the Royal National Hospital for Rheumatic Diseases in Bath, England.
“In someone who’s under the age of 45, if they’ve had more than 3 months of back pain, then you should be thinking about axial spondyloarthritis already,” he said.
“The proviso is that in someone who’s older, actually asking them when their back pain started is relevant, because that person may have had symptoms that started at age 20, but for whatever reason, they didn’t seek help,” said Dr. Sengupta. “They could still have undiagnosed axial spondyloarthritis.”
Women can be affected as much as men
Importantly, it appears that women can be just as affected as men, particularly in the early stages of the disease, said Dr. Sengupta.
“In the old days, people just thought of it as a ‘men-only’ disease, but what we’ve learned is that the earlier stage of the disease, the prevalence is much more 50:50,” he said.
“The sad part is that over the years women have been really underdiagnosed because of this false message that has gone about, saying women can’t get it. So, sadly, you see greater delays in diagnosis in women because of that.”
Other symptoms and associated conditions
In people with early axSpA, “pain tends to be over the sacroiliac joints, which is over the buttocks, so it’s often confused with sciatica,” explains Dr. Sengupta. Alternating buttock pain is something to take note of, as is tendonitis and enthesitis. The latter is inflammation where the tendons or ligaments are inserted into bone, so it means that people may have problems such as Achilles heel, tennis elbow, or even musculoskeletal chest pain. Dactylitis – swollen fingers or toes – is another sign seen in some people with axSpA.
Associated conditions (including family history)
- Psoriasis.
- Inflammatory bowel disease.
- Eye inflammation (uveitis or iritis).
“Family history is also really important,” although not essential, Dr. Sengupta said. And not only if there is axSpA in the family, but also if there are other conditions such as psoriasis or inflammatory bowel disease. Another commonly associated condition is eye inflammation, which can be uveitis or iritis.
What about tests and tools?
Testing for HLA-B27 – which has a known association with axSpA – and measuring blood levels of C-reactive protein may be helpful, but “even if they are normal, that shouldn’t be reassuring you that this can’t be ankylosing spondylitis [in a patient with a] strong inflammatory back pain story.”
Ordering an MRI scan may be possible within primary care, depending on where you are in the world, but the results do need to be interpreted with expert eyes, Dr. Sengupta advises.
There are online tools available to help with the diagnosis of axSpA, Dr. Sengupta said, such as the Spondyloarthritis Diagnosis Evaluation Tool (SPADE). Efforts are also underway to create online systems that help to flag symptoms in general practice.
Tests and tools
- HLA-B27 association.
- Elevated C-reactive protein.
- Sacroiliitis on MRI.
- SPADE tool.
The bottom line is that many more patients could potentially be identified earlier in primary care by careful assessment of the clinical symptoms and asking about the family history and associated conditions.
At its simplest, if you see “someone under the age of 45, if they’ve had 3 months of back pain, and they keep on coming back to say, ‘My back’s really bad,’ think about axial spondyloarthritis,” said Dr. Sengupta.
A version of this article first appeared on Medscape.com.