Seems to have some similarities with CFS, but PEM seems to be a clear differentiator (immune symptoms also seem to be absent in Chiaru malformation). Still it seems like a great idea to check for people who don't have a clear-cut ME/CFS.
I had severe PEM for years, the classic ME/CFS differentiating type. Sometimes, even while lying flat, just watching a TV screen would cause severe PEM. I also had EBV (positive IGM and PCR) as well as low NK Cell function. At my worst, I couldn't speak, due to exhaustion. Overall, I've had severe POTS, MCAS, and CFS/ME. I've been hospitalized multiple times for MCAS.
It turns out that I have cranial settling, with my skull sinking downward onto my spine, causing brain stem compression. This sinking downward isn't outwardly visible, so you couldn't tell from just looking at me. (This sinking downward also is not a Chiari Malformation, but it is similar, as it can result in cerebral spinal fluid problems as well as autonomic nervous system issues.)
I needed an upright flexion-extension MRI to find the problem, and I then needed to send the MRI image to a knowledgeable neurosurgeon, as the radiology report was negative. The MRI revealed to the neurosurgeon that my skull has been sinking down into my spine, due to lax ligaments from Ehlers-Danlos Syndrome (EDS). The result is brain stem compression. My spine is protruding into my skull, touching my brain stem and compressing it. This is not
supposed to happen! This causes many neurological problems, such as in fatigue (PEM-type), POTS, etc.
As for the immunological signatures unique to CFS/ME, it could be that neurological compromise results in specific immune disruption. Our nervous system and immune system are intertwined. A deficit in one system can result in the other system becoming abnormal.
At any rate, my craniocervical problem is entirely correctable with neurosurgery. I'm scheduled for surgery at the end of the month. But for now, I'm in a halo vest that's keeping my head from sinking onto my spine.
In the halo, I no longer have POTS. I no longer have PEM. My ME/CFS might have been, all along, a neurosurgical/structural problem.
Since my severe onset in 2014, I had angrily wished that this disease were curable with surgery or chemo. Well, it now seems like it is. At least the type that I have.
And how many others are just like me, but undetected?