In the seventh of the ME Association’s ME/CFS experts video series on the immune system and viruses we’re really getting into the heart of things.  Dr. DeMeirleir co-wrote a densely technical book on immune interactions in ME/CFS called ‘Chronic Fatigue Syndrome A Biological Approach’ about a decade ago and he’s well versed in the immune side of ME/CFS.  Problems in the immune system, he believes, are at the core of this disorder.


Pathogens in ME/CFS

Dr. De Meirleir reports many patients have multiple infections but pathogens are not the culprit…..

Pathogens in chronic fatigue syndrome (ME/CFS) are a  controversial topic at this point.  They’re a focal point for some physicians and hardly considered by others.  It may be that patients with pathogens tend to flock more to some practitioners or some practitioners just don’t test for them. The fact that many of the pathogens associated with this disorder are either hard to find or are believed to  exist in strange forms doesn’t help.

In any case, we’ll know a lot more about the role viruses play in chronic fatigue syndrome as the Chronic Fatigue Initiative’s  pathogen  studies start appearing this year but Dr. De Meirleir believes  pathogens provide a starting point for about half the chronic fatigue syndrome population and that several infections are active simultaneously in many patients.

He described a process  where infections stir up a disturbed immune system  that’s not powerful enough to handle the pathogens but is still plenty capable of making your life miserable.  Describing a kind of cascading process of debilitation, De Meirleir  believes  the immune system continues to buckle under the strain over time in many patients, further exacerbating symptoms.  Don’t hold the viruses responsible, though; it’s that under-functioning immune system that is definitely the culprit.


Still the pathogens are there and they must be dealt with. We haven’t heard much about enteroviruses lately but Dr. De Meileir endorsed Dr. Chia’s finding of 80% prevalence in the gastrointestinal system. (Speaking of which De Meirleirs video on the gut, a big focus of his, is going to be interesting.  Given that Dr. Chia is an infectious disease specialist  we might also expect a higher percentage of virus infected patients in his office.

Dr. De Meileir finds the usual suspects (HHV-6, EBV, Cytomegalovirus, parvovirus) as well as bacterial infections (mycoplasma, chlamydiae)  and parasites (eg. Giardia). This many pathogens obviously points to some sort of hole in the immune system.

Dr. De Meirleir nominated a mutation in the T cytotoxic cells, dysfunctional and low levels of natural killer cells (NK) and nagalese.  Proof of immune activation comes in elevated cytokine levels. Cytokine study results have been all over the map in ME/CFS but Dr. DeMeirleir description of  patients with  high cytokine levels brought to mind patients with similar immune signatures seen by Dr. Peterson and Dr. Klimas.  (How interesting that multi-site ME/CFS expert study will be; these  immune activated/challenged patients should pop out in that study like popcorn. ).

Dr Meileir noted that the list of cytokines, chemokines and interleukins associated with ME/CFS  was just the beginning; he’s identified other  immune abnormalities that are in kind of medical limbo for the time being. These immune factors are present in elevated levels in ME/CFS  but no one knows quite what their significance is.


The big news from the De Meirleir clinic now are elevated levels of  nagalese, an enzyme that knocks out macrophages –  the  major garbage cleaners in the blood. De Meirleir reported nagalese is elevated in  almost all (97%) of his  patients.  Macrophages, it turns out,  have to be prodded to act and nagalese stops this from happening.  (Both Dr. DeMeirleir and Dr. Cheney reported on nagalese levels in association with GcMAF at the Ottawa ME/CFS Conference.)

So where is all this nagalese coming from?  In one of those devilishly clever pathogenic strategies  some intestinal bacteria appear able to produce it ( presumably in order to keep macrophages from gobbling them up). That’s the theory right now, it hasn’t been proven but it does provide the enticing possibility that fixing the gut could help out the immune system.

Surprisingly, no mention was made of RNase L and the interferon system Dr DeMeirleir was so involved in for years.  Both Dr. Peterson and Dr. Lombardi believe that enzyme plays a key role in some ME/CFS patients.

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