Table 2 Disease characteristics contributing to diagnostic delay for patients with axSpA

Back pain is very common, axSpA is not

D25: in primary care general practice, … there’s the old adage when you hear hoofbeats, think horses, not zebras. So, ankylosing spondylitis is a zebra.

D10: it’s certainly not on the top three things I think of when somebody comes in and says my back hurts. So, and, you know, I’m not sure if I’m just missing it because I’m not looking for it or is it just relatively rare

Slow disease progression

D34: Or things behave similarly early on, and advanced imaging or blood tests may be easy not to do based on let’s try this, let’s try that, and if things don’t get better, that usually is that patients come back and other symptoms start arising. So it might take a while for more systemics to arise that might put that on the radar of the physician to work up further.

D5: You know, it progresses over time and you -- before you get to bamboo spine.

Intermittent nature of pain with axSpA

D24: Well, patients are often, when they’re uncomfortable -- well, unless they’re getting, you know, they’re having a flare and then nothing for a few years and then getting a flare, nothing.

D22: a lot of pain generally improves with time, especially acute -- either acute pain or acute flareup sorts of pain, so it kind of gives the patient, you know, a couple of weeks. Usually by that time the pain always -- almost always goes away.

Lack of characteristic radiographic appearances

D11: Part of the delay, one would think, is probably related to the lack of characteristic radiographic appearance of -- sacroiliitis sounds great for you and I to talk about but the radiograph isn’t always, you know, knock your socks off. It takes a while until you start obscuring the joint margin.

D22: The patient was there for something else and he said that okay, I’ve been having a lot of stiffness in the morning and that was – he had typical symptoms but when we did his x-ray there was nothing specific.

No definitive test for diagnosis

D24: I would probably move to imaging before I would get something like a B27 simply because -- and, I’ll be honest, I don’t know the percentages here, … we have more back pain from arthritis and disks and it’s such a common problem. The amount of people who are going to have a positive B27 is fairly low.

D3: I have sent them for a work up. Most of the time it’s been negative.