The problem of diagnosing Psoriatic Arthritis

Diagnosing PsA

Psoriatic arthritis is apparently quite a hard illness to diagnose. With other similar forms of inflammatory arthropathy there are usually markers that show up in blood tests that can help in confirming a diagnosis. Psoriatic arthritis is generally diagnosed based on the experience of a rheumatologist and an observation of symptoms.

One of the most objective test that a physician can do in confirming the presence of symptoms of psoriatic arthritis is simple measurements of areas in which there is pain. Generally if there is pain then there will be associated swelling. In fact, my diagnosis was largely based on the dactylitis of three of my fingers. They were swollen to the point that it was easy to see that there was an issue. More recently I have had a swollen DIPJ. The pain is there but the swelling was only slight. In fact, the circumference of the joint was only 0.2 cm bigger than it's equivalent on the opposite side.

Another tool in the diagnostic arsenal is simply to start treating. If you treat with anti-inflammatories and the body reacts favourably then it's a pretty clear sign that there was inflammation present. In fact, the effectiveness of the anti-inflammatories on me revealed more specifically that I was suffering from inflammation more so than the specific blood tests for inflammation (erythrocyte sedimentation rate and C-reactive protein). The problem is, although there has clearly been a response from my body, there is no objective way to measure the level of the response.

Why is this a problem?

I'm shortly (hopefully!) about to change rheumatologist to an NHS one, or rather I'm going to augment my care plan with an NHS one. This is primarily because I have no medical insurance and it would be prohibitively expensive to be treated privately forever. Unfortunately, the NHS rheumatologist is unlikely to accept my private diagnosis on face value. I have some photos of the dactylitis at it's worst in my fingers, which may be the clincher, and my experience with the anti-inflammatories, which becomes less accurate as time goes on. What I intend to take is a full set of baseline measurements of joint circumferences on my hands, as well as a record of the measurements taken by my hand therapist. This is my proof of swelling and specific joint problems. Once I've proved that I'm hoping that they'll take my word for the more objective symptoms.