I assume that you are aware of the report that the UK post mortem research group published in the The Journal of Neurological Sciences.
This describes some of the more interesting findings, including dorsal root ganglionitis, that have been found in a few cases involving people with ME/CFS.
These are people who have often died in tragic ciurcumstances and where relatives have given permission for post-mortem tissue to be used for research purposes.
An abstract is provided below.
The dorsal root ganglia (DRG) are, in very simple terms, minute bundles of nerve cell bodies that lie outside the spinal cord - and so form part of the peripheral nervous system.
So inflammation of the DRG is not the same as myelitis in MEncephalomyelitis. Myelitis refers to inflammation of the spinal cord.
The DRG appear to be involved in the transmission of sensory information and possibly pain as well, and so disturbances in function may result in sensory disturbances and pain.
Dorsal root ganglionitis, inflammation of the DRG, can be caused by an infection such as chickenpox.
But it can also be associated with specific conditions such as Sjogren's Syndrome - which has some interesting overlaps with ME/CFS, including debilitating fatigue.
In the case of SS, the presence of DRG-itis has been linked to the sensory neuropathy that occurs.
As far as ME/CFS is concerned, we just don't know at this stage whether DRG-itis is part of the disease process, or whether it could just be the result of a triggering infection such as herpes.
As we do more post mortems, which is happening despite the lack of a formal post-mortem facility, the position may become more clear.
ABSTRACT:
Pathology of Chronic Fatigue Syndrome: Pilot Study of Four Autopsy Cases
DG O’Donovan1, 2, T Harrower3, S Cader2, LJ Findley2, C Shepherd4, A Chaudhuri2
1Addenbrooke’s Hospital Cambridge UK
2Queen’s Hospital Romford Essex UK
3Royal Devon & Exeter Hospitals UK
4Honorary Medical Advisor to ME Association UK
Chronic Fatigue Syndrome / Myalgic Encephalomyelitis is a disorder characterised by chronic exercise induced fatigue, cognitive dysfunction, sensory disturbances and often pain. The aetiology and pathogenesis are not understood.
We report the post mortem pathology of four cases of CFS diagnosed by specialists.
The causes of death were all unnatural and included: suicidal overdose, renal failure due to lack of food and water, assisted suicide and probable poisoning.
Selected portions of tissue were made available by the various Coroners in the UK and with the assent of the persons in a qualifying relationship.
The cases were 1 male, and 3 female. Ages (years) M32, F32, F43 & F31.
One case showed a vast excess of corpora amylacea in spinal cord and brain of unknown significance but Polyglucosan Body Disease was not supported by clinicopathologial review. No ganglionitis was identified.
One case showed a marked dorsal root ganglionitis and two other cases showed mild excess of lymphocytes with nodules of nageotte in the dorsal root ganglia.
This raises the hypothesis that dysfunction of the sensory and probably also the autonomic nervous system may lead to abnormal neural activity eg hyperalgesia & allodynia rather than anaesthesia and may explain some of the symptoms of CFS / ME such as pain, hypotension, hyperacusis and photophobia. However, the syndrome may be heterogeneous.
Nevertheless, the precise relationship of fatigue, which may be either peripheral or central, to abnormalities in the peripheral nervous system (PNS) needs to be studied.
The differential diagnosis of ganglionitis should be investigated in CFS / ME patients hence Varicella Zoster, Lyme disease, HIV, Sjogren’s disease, paraneoplastic sensory ganglionopathy should be excluded by appropriate history and tests.
Thorough histopathological study of cases coming to autopsy may help to confirm or refute the hypothesis, that CFS is a disease process, and whether the symptomatology may be explained by inflammation of the sensory and autonomic divisions of the PNS.
A specific CFS / ME brain and tissue bank in the UK is proposed.