Fibromyalgia - getting it right
A little while back a fellow consultant asked my opinion on a radiograph of a patient’s hand. The patient had previously been diagnosed with rheumatoid arthritis. However, we analysed the images together, and saw that rhomboid, negatively birefringent crystals seen under polarising light microscopy had just been drawn out of the fluid in the wrist and noting negative test results for rheumatoid factor and anti-CCP antibodies in the blood, we agreed the diagnosis was chronic calcium pyrophosphate dihydrate polyarthritis and not rheumatoid arthritis. Our friendly musculoskeletal radiologist confirmed matters later. A re-diagnosed case then.
Re-diagnosis and mis-diagnosis, unfortunately, happens more than you think. It’s natural that doctors, like all humans, make mistakes. Fibromyalgia, for example, can be over-diagnosed. – too much use of the ‘F’ word. Two other patients under my team’s care have just had their Fibromyalgia diagnosis kicked into touch (if you need to know, one patient had enthesopathic-predominant psoriasis-related musculoskeletal disease, and the other had low grade inflammatory bowel disease (IBD) related musculoskeletal symptoms [and fatigue from the previously undisclosed IBD]).
Sensible medical opinion defines Fibromyalgia as a term used to describe the amplification of pain through aberrant brain neural pathways (or for the scientists out there: nociceptor inputs can trigger a prolonged but reversible increase in the excitability and synaptic efficacy of neurons in central nociceptive pathways, termed central sensitization). Essentially, factors such as non-restorative sleep and psychological issues affect brain processing of pain signals leading to enhanced pain perception (pain ‘plus’). Some specialists who see a lot of people with Fibromyalgia interestingly note a high frequency of unresolved internal psychological conflict in their patients, and previous abuse can be one of the causes.
Fibromyalgia features follow well-established patterns – primarily widespread pains and tender points around the body. Fatigue is often present. Diagnostic criteria (ACR 2010) exist [https://www.rheumatology.org/Portals/0/Files/2010_Preliminary_Diagnostic_Criteria.pdf] and have been honed iteratively over the years to currently allow quite a precise diagnosis to be made.
Can we all get it? In theory. Is it a disease in itself? Possibly can be. Is it over-diagnosed? Certainly. So often we find the diagnosis is thrown in without a prior broad and in-depth clinical assessment of the totality of symptomology, and without appropriate investigation of what else may be causing symptoms. There are probably two main factors in generating an erroneous Fibromyalgia diagnosis. The first is not applying the criteria for Fibromyalgia correctly. The criteria are there for a reason, and they are sound. The second reason – often combined with the first – is that the diagnosis is often levied by those who believe they know what Fibromyalgia is, but have little knowledge of what else might be there to cause symptoms; i.e. to part-quote Donald Rumsfield… ‘they don’t know what they don’t know’. How do you exclude medical conditions about which you have little or no knowledge and therefore can’t investigate?
There are quite a few autoinflammatory and autoimmune conditions which are subtle, episodic, come and go, can cause pain and/or fatigue and/or tender areas, and can generate abnormal blood tests (or sometimes don’t)… but are not Fibromyalgia. To the unknowledgeable or unwary, these conditions can be erroneously assigned the F-word. So, who actually knows about all this though? Who should you go and ask? Well, your best bet is a Rheumatologist –an experienced one! A good rheumatologist should be able to confirm the F-word diagnosis, and consider if it is a Primary (the only) diagnosis or Secondary (to, or accompanying, another underlying condition) or most importantly of all, should be able to correct an erroneous diagnosis of Fibromyalgia and successfully treat the right condition.