I keep reading about what is called ‘neuroinflammation’ in relation to research into ME/CFS. I assume this means inflammation in the nervous system. But is this the same as encephalomyelitis (the E in ME)? I know that encephalomyelitis is largely dismissed by many doctors and is the reason why some doctors refuse to even use the name ME/ myalgic encephalomyelitis.
As you say, neuroinflammation is used to describe what is often regarded as low level inflammation in the nervous system. Neuroinflammation occurs in number of inflammatory and infective diseases where it can form part of a more generalised inflammation (as with a rheumatic condition like lupus).
Or it can be part of an ongoing immune system response to an infection (as can occur in chronic hepatitis C and HIV/AIDS) where inflammatory chemicals called cytokines are entering the nervous system and causing inflammation. It also occurs in other neurological diseases —Alzheimer's and Parkinson's disease for example — that do not involve encephalomyelitis.
The presence of neuroinflammation in ME/CFS, as was described in a recent neuroimaging research study from Japan, does NOT mean that people with ME/CFS have what neurologists and neuropathologists would recognise or define as an encephalomyelitis.
Encephalomyelitis is normally used by clinicians and pathologists to describe a widespread and more significant inflammation involving both the brain and spinal cord. From a clinical point of view, encephalomyelitis normally presents with severe neurological symptoms and signs, which may be life-threatening something that is most unusual during the early acute post-infectious stages of ME/CFS.
There is, at present, no pathological or neuro-radiological evidence to indicate that people with ME/CFS have an encephalomyelitis, and that includes the findings from the post-mortem research group of which I am a member. Like everyone else, I want to establish what the neuropathology of ME/CFS actually is — but there is no point in coming to flawed conclusions about cause unless there is sound scientific evidence to demonstrate what you are claiming.
Incidentally, the UK post-mortem research group to which I belong has published some preliminary findings from post-mortems involving people with ME/CFS in the Journal of Neurological Sciences.
These results, from a small number of cases, again indicate that neuroinflammation in the form of inflammation of the dorsal root ganglia (part of the peripheral nervous system) occurs in some people with ME/CFS. This could be causing some of the sensory symptoms (pain, numbness, abnormal sensations) that may occur in ME/CFS.
More information on this research can be found in the research section of the ME Association's ME/CFS/PVFS Clinical & Research Guide (also known as the ‘purple book').
Medical Matters is for information purposes only. The answers provided by Dr Shepherd and the ME Association’s other expert advisers should not be construed as medical advice. We recommend that any information you deem relevant is discussed with your GP as soon as possible. It is important to obtain advice from a GP who is in charge of your clinical care, who knows you well, and who can consider other likely causes for symptoms. Seek personalised medical advice whenever a new symptom arises, or an existing symptom worsens. Don't assume that new or worsened symptoms are a result of having ME/CFS.