Yeah, it’s a strange one because it’s two different diseases in one.

Since the 1980s, a disease characterised by fatigue and mostly thought to be caused by psychological factors has been called “chronic fatigue syndrome”.

Since then, we (biomedical researchers) have found a far more specific disease within this broad category, often caused by viral infections, which we named Myalgic Encephalomyelitis, which is what an original outbreak was called in London, I believe.

Anyhow, M.E. has very strict diagnostic criteria, requires some features that don’t present in any other illnesses, and requires a substantial decrease in physical functioning (>50%). Here’s the International Consensus Criteria for example. Interestingly, some cases present without the “main symptom” of fatigue, as defined by chronic fatigue syndrome. Most chronic fatigue syndrome diagnosis criteria, such as the Oxford Criteria, require only unexplained disabling fatigue. For M.E. subgroups defined by strict criteria, we also have clear physical abnormalities present, which show it is a physical disease and not psychosomatic.

The problem arises because most of these discoveries were made in the past decade. So, nearly every trained doctor and medical professional who advises the government treats M.E. as a “psychosomatic fatigue disease,” which is really far from what it actually is. This has even led to a few high-profile cases of patients dying in care after being refused a feeding tube and dying of starvation, for example, since M.E. can cause fatal gastroparesis.

In practice, patients are often treated for psychosomatic fatigue and even blamed for their symptoms, which is far from the actual case. Unfortunately, most of the English-speaking world is quite behind on this. The Mayo Clinic Proceedings is decent, but the CDC, NHS, and NIH are still holding onto some outdated beliefs. The real push has come from Austrian and German-speaking medicine (including Dutch), where some major discoveries have been made recently.

We had a young patient tragically die in our care a couple of months ago; there seem to be some cases that are progressive.

It’s similar to fibromyalgia in that it includes a lot of symptoms, is of unclear aetiology, and has often been treated as psychosomatic in the past. But, in practice, they are quite different diseases, with fibromyalgia being characterised by high levels of pain and thought to be a pain processing disorder with “central amplification.” Meanwhile, M.E. is mostly characterised by severe functional disability, and we have found different immune abnormalities and depletions, as well as problems with mitochondria and increased clotting. As of now, we don’t know how this all fits together. Something I find interesting is the only drug that has had some positive clinical trial results is an AIDS drug. Although none are approved for the disease as of now.