Thursday, 8 January 2015

Abdominal discomfort syndrome in a subset of ME/CFS

"The findings show that ADS [abdominal discomfort syndrome] is a characteristic of a subset of patients with ME/CFS [Myalgic Encephalomyelitis / Chronic Fatigue Syndrome] and that increased bacterial translocation (leaky gut) is associated with ADS symptoms."
Right there. God does not build in straight lines.

So said the study by Michael Maes and colleagues [1] looking at both gastrointestinal (GI) symptom presentation in diagnosed cases of ME/CFS and "the IgA and IgM responses directed against commensal bacteria" - rough translation: an immune system response against some of those microscopic beasties that call us home (residing in our deepest, darkest recesses). Leaky gut by the way, is something that I'm particularly interested in on this blog for quite a few different reasons (see here) and refers to potential issues with the barrier separating the contents of our GI tract from the wider body and the ever-vigilant immune system. Dysfunction of said barrier might mean that an immune response against bacteria are more likely as per a certain Sutterella finding in autism research a few years back. And before you ask, yes, leaky gut is a real concept despite some who would say otherwise...

The term 'abdominal discomfort syndrome' akin, I think, to something around irritable bowel syndrome based on the results of the cluster analysis "performed on gastro-intestinal symptoms" by Maes et al, is an interesting finding. It is not necessarily new news that there may be sub-groups of people described under the label of ME/CFS, one of which might be a 'gut related subgroup' (see here). Indeed, gut inflammation has been mentioned on more than one occasion [2] with something of a connection to the presentation of more functional bowel issues.

What is perhaps novel about the Maes findings is the authors' assertion that their study results point to: "a pathway phenotype, i.e bacterial translocation, that is related to ME/CFS and ADS/IBS and that may drive systemic inflammatory processes." This comes on the back of other evidence suggesting that issues with gut permeability associated with the process of bacterial translocation may be present in cases of ME/CFS and potentially amenable to intervention [3] (although I hasten to add that further research is required on this topic).

Michael Maes is quite a prolific peer-reviewed author when it comes to ME/CFS tapping into some really, really interesting areas of research such as mitochondrial dysfunction [4], oxidative stress [5] and autoimmunity [6]. This latest research venture adds further to the notion that genetics and biology are the drivers of quite a large proportion of cases covered under the umbrella term 'overlapping fatigue syndromes' [7].

And then some music. How about Yellow from Coldplay?

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[1] Maes M. et al. Evidence for the existence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) with and without abdominal discomfort (irritable bowel) syndrome. Neuro Endocrinol Lett. 2014 Nov 2;35(6):445-453.

[2] Lakhan SE. & Kirchgessner A. Gut inflammation in chronic fatigue syndrome. Nutr Metab (Lond). 2010 Oct 12;7:79.

[3] Maes M. et al. Normalization of the increased translocation of endotoxin from gram negative enterobacteria (leaky gut) is accompanied by a remission of chronic fatigue syndrome. Neuro Endocrinol Lett. 2007 Dec;28(6):739-44.

[4] Morris G. & Maes M. Mitochondrial dysfunctions in myalgic encephalomyelitis/chronic fatigue syndrome explained by activated immuno-inflammatory, oxidative and nitrosative stress pathways. Metab Brain Dis. 2014 Mar;29(1):19-36.

[5] Morris G. & Maes M. Oxidative and Nitrosative Stress and Immune-Inflammatory Pathways in Patients with Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS). Curr Neuropharmacol. 2014 Mar;12(2):168-85.

[6] Morris G. et al. The emerging role of autoimmunity in myalgic encephalomyelitis/chronic fatigue syndrome (ME/cfs). Mol Neurobiol. 2014 Apr;49(2):741-56.

[7] Whiteley P. et al. Correlates of Overlapping Fatigue Syndromes. Journal of Nutritional and Environmental Medicine. 2014; 14: 247-259.

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ResearchBlogging.org Maes M, Leunis JC, Geffard M, & Berk M (2014). Evidence for the existence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) with and without abdominal discomfort (irritable bowel) syndrome. Neuro endocrinology letters, 35 (6), 445-453 PMID: 25433843