Can you help the doctors of the future understand ME?

Can you help the doctors of the future understand ME?

What should medical students learn about ME?

Email Dr Nina Muirhead nina.muirhead@nhs.net with a list of what you think medical students should learn about the condition.

Nina has already sent a questionnaire to UK medical schools and would like to compare what is actually being taught, to what patients think should be taught, so she can campaign for better medical education.

Be aware that the amount of time available to spend on individual conditions in a medical course is very small, so select the key topics.

Dr Muirhead is a Dermatology surgeon in Buckinghamshire, a tutor & research supervisor at Cardiff University Medical school and a person with ME.

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Impairments in cognitive performance in CFS are common, not related to co-morbid depression but do associate with autonomic dysfunction

Impairments in cognitive performance in chronic fatigue syndrome are common, not related to co-morbid depression but do associate with autonomic dysfunction, by
Lucy J Robinson, Peter Gallagher, Stuart Watson, Ruth Pearce, Andreas Finkelmeyer, Laura Maclachlan, Julia L Newton in  PLoS ONE 14 (2) [Published: February 5, 2019]

Research abstract:

Objectives:
To explore cognitive performance in chronic fatigue syndrome (CFS) examining two cohorts. To establish findings associated with CFS and those related to co-morbid depression or autonomic dysfunction.

Methods:
Identification and recruitment of participants was identical in both phases, all CFS patients fulfilled Fukuda criteria. In Phase 1 (n=48) we explored cognitive function in a heterogeneous cohort of CFS patients, investigating links with depressive symptoms (HADS). In phase 2 (n=51 CFS & n=20 controls) participants with co-morbid major depression were excluded (SCID). Furthermore, we investigated relationships between
cognitive performance and heart rate variability (HRV).

Results:
Cognitive performance in unselected CFS patients is in average range on most measures. However, 0-23% of the CFS sample fell below the 5thpercentile. Negative correlations occurred between depressive symptoms (HAD-S) with Digit-Symbol-Coding (r=-.507, p=.006) and TMT-A (r=-.382, p=.049). In CFS without depression, impairments of cognitive performance remained with significant differences in indices of psychomotor speed (TMT-A: p=0.027; digit-symbol substitution: p=0.004; digit-symbol copy: p=0.007; scanning: p=.034) Stroop test suggested differences due to processing speed rather than inhibition.

Both cohorts confirmed relationships between cognitive performance and HRV (digit-symbol copy (r=.330, p=.018), digit-symbol substitution (r=.313, p=.025), colour-naming trials Stroop task (r=.279, p=.050).

Conclusion:
Cognitive difficulties in CFS may not be as broad as suggested and may be restricted to slowing in basic processing speed. While depressive symptoms can be associated with impairments, co-morbidity with major depression is not itself responsible for reductions in cognitive performance. Impaired autonomic control of heart-rate associates with
reductions in basic processing speed.

Graphic from pngtree.com
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A Winter’s Tale – a former mountain climber reflects on PEM & ME/CFS/FM

Health rising blog post, by Simon Parker, 5 Feb 2019: A winter’s tale – a former mountain climber reflects on Post Exertional Malaise and ME/CFS/FM.

Fifteen years ago I was diagnosed with Fibromyalgia and ME (aka Chronic Fatigue Syndrome), a debilitating condition that includes continual pain and delayed fatigue as its primary symptoms.

I often find myself trying to explain to other people what the delayed fatigue is like by giving an example that describes the degree of exhaustion I experience …

Have you ever been Winter Climbing?

Well let me tell you a tale …

[Simon tells the story of a tough climb in snow and ice, concluding:]

I was utterly exhausted from the physical efforts of the day and I hadn’t realised that the cotton underclothing I was wearing was soaked through. A combination of sweat from the physical effort of the climb and the copious amounts of water from the snow showered over me during the boulder-in-the-gully incident had seeped through my clothes and my padded mountain jacket.

The heat from my body core was draining away and the sub-zero wind chill was not helping. Tunni walked ahead of me breaking a path and I followed, using his footsteps to make each step I took easier. By the time we reached the mouth of the cwm, I was flailing and failing. Each step required a Herculean effort and I was falling further and further behind.

I remember thinking that I would sit down and rest for a couple of minutes to recover myself. Even as I lay back into the snowdrift, I realized that if I didn’t get up, there and then I would simply fall asleep and die of exposure, and at this juncture my resolve was overcome by a fatigue that went beyond movement and reason. I had become hypothermic. Blood wasn’t reaching my legs, arms, or brain. I was drifting into that blissful state between waking and sleep.

My brain was shutting down and I didn’t care …

All I recall of the remainder of that day is a dim memory of being hauled to my feet and half-carried the remainder of the way to the car; sometime later standing in front of a roaring fire whilst being plied with large mugs of hot tea; and a long hot bath to gently re-heat my body core back to normal.

That’s what friends are for.

They save your life.

And now, in 2019, I get to feel like this whenever I do more than I’m capable of; like walking upstairs or having a bath.

And when I’m asked, ‘How fatigued are you’?

Well, this is my measure.

Paul Tunnicliffe – Diary entry for 10 Feb 1996

“Winter Climb. Black Ladders. Eastern Gully with Simon, Loads of snow. Walk-in took 4 hours! v.knackered. climb took over 4 hours. so much banked up powder the climb was hard to start, even. Si had a couple of new screws & pegs and I got placements on the first bit and belayed on the lip with no rope left. Snow in the gully proper a bit dodgy looking and loose(ish) and we ‘daggered’ about 90% of it. 5.00pm top out and v.exhausting walk out mainly with head-torches during which I lost the spare battery and Swiss army knife and Simon had an epic! A good day.”
Dedicated to Paul ‘Tunni’ Tunnicliffe and Mark Pither

Simon Parker is now 62 years old. He lives in rural Anglesey, North Wales. His story:

Simon Parker
In 2000 I was completing my PhD in Pedagogy at Bangor University North Wales and enjoying an active outdoor lifestyle, when I caught a bout of flu that resulted in increasing periods of debilitating fatigue and pain after exercising. I was diagnosed in 2003 with fibromyalgia and ME/CFS.

When I was first diagnosed I underwent the procedures recommended by my local ME/pain clinic (CBT & GET) who advised me to ‘exercise to my full capacity as the condition is temporary’ – a course of action which only made my symptoms worsen.

Luckily I found a ME/CFS consultant (Dr Sarah Myhill) whose tests and approach (leaky gut, PK diet, and mitochondrial functioning, etc.) made a huge difference in understanding the condition and in taking appropriate steps to mitigate the worst of the symptoms.

My symptoms have increased in severity over time and I now spend about 80% of my time in bed and the remaining 20% of my time trying not to over-exert myself while making time-lapse videos of blossoming trees in my locale each Spring.

I still (literally) dream of going climbing and live in hope that the current research avenues will one day lead to a cure or at the least an alleviation of the symptoms so that I could go rock climbing again with my son.

Read full article

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Evaluation of four clinical laboratory parameters for the diagnosis of ME

Evaluation of four clinical laboratory parameters for the diagnosis of myalgic encephalomyelitis, by Kenny L. De Meirleir, Tatjana Mijatovic,
Krishnamurthy Subramanian, Karen A. Schlauch and Vincent C. Lombardi in
Journal of Translational Medicine 2018 16:322 [Published: 21 November 2018]

Research abstract:

Background:
Myalgic encephalomyelitis (ME) is a complex and debilitating disease that often initially presents with flu-like symptoms, accompanied by incapacitating fatigue. Currently, there are no objective biomarkers or laboratory tests that can be used to unequivocally diagnosis ME; therefore, a diagnosis is made when a patient meets series of a costly and subjective inclusion and exclusion criteria. The purpose of the present study was to evaluate the utility of four clinical parameters in diagnosing ME.

Methods:
In the present study, we utilized logistic regression and classification and regression tree analysis to conduct a retrospective investigation of four clinical laboratory [tests] in 140 ME cases and 140 healthy controls.

Results:
Correlations between the covariates ranged between [− 0.26, 0.61]. The best model included the serum levels of the soluble form of CD14 (sCD14), serum levels of prostaglandin E2 (PGE2), and serum levels of interleukin 8, with coefficients 0.002, 0.249, and 0.005, respectively, and p-values of 3 × 10−7, 1 × 10−5, and 3 × 10−3, respectively.

Conclusions:
Our findings show that these parameters may help physicians in their diagnosis of ME and may additionally shed light on the pathophysiology of this disease.

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Relationship between exercise-induced oxidative stress changes & parasympathetic activity in CFS

Relationship between exercise-induced oxidative stress changes and parasympathetic activity in Chronic Fatigue Syndrome: an observational study in patients and healthy subjects, by Andrea Polli, Jessica Van Oosterwijck, Jo Nijs, Uros Marusic, Inge De Wandele, Lorna Paul, Mira Meeus , Greta Moorkens, Luc Lambrecht, Kelly Ickmans

Research abstract:

Purpose:
Oxidative stress has been proposed as a contributor to pain in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). During incremental exercise in patients with ME/CFS, oxidative stress enhances sooner and antioxidant response is delayed. We explored whether oxidative stress is associated with pain symptoms or pain changes following exercise, and the possible relationships between oxidative stress and parasympathetic vagal nerve activity in patients with ME/CFS versus healthy, inactive controls.

Methods:
The present study reports secondary outcomes from a previous work. Data from 36 participants were studied (women with ME/CFS and healthy controls). Subjects performed a submaximal exercise test with continuous cardiorespiratory monitoring. Levels of thiobarbituric acid–reactive substances (TBARSs) were used as a measure of oxidative stress, and heart rate variability was used to assess vagal activity. Before and after the exercise, subjects were asked to rate their pain using a visual analogic scale.

Findings:
Significant between-group differences in pain at both baseline and following exercise were found (both, P < 0.007). In healthy controls, pain was significantly improved following exercise (P = 0.002). No change in oxidative stress level after exercise was found. Significant correlation between TBARS levels and pain was found at baseline (r = 0.540; P = 0.021) and after exercise (r = 0.524; P = 0.024) in patients only. No significant correlation between TBARS and heart rate variability at baseline or following exercise was found in either group. However, a significant correlation was found between exercise-induced changes in HRV and TBARS in healthy controls (r = −0.720; P = 0.001).

Implications:
Oxidative stress showed an association with pain symptoms in people with ME/CFS, but no exercise-induced changes in oxidative stress were found. In addition, the change in parasympathetic activity following exercise partially accounted for the change in oxidative stress in healthy controls. More research is required to further explore this link.

Read article in full

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Changes in the transcriptome of circulating immune cells of a N Z cohort with ME/CFS

Changes in the transcriptome of circulating immune cells of a New Zealand cohort with myalgic encephalomyelitis/chronic fatigue syndrome, by Eiren Sweetman, Margaret Ryan, Christina Edgar, Angus MacKay, Rosamund Vallings, Warren Tate in International Journal of Immunopathology and Pharmacology vol 33 2019 [Published January 11, 2019]

 

Research abstract:
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a poorly understood disease affecting 0.2%–2% of the global population. To gain insight into the pathophysiology of ME/CFS in New Zealand, we examined the transcriptomes of peripheral blood mononuclear cells by RNA-seq analysis in a small well-characterized patient group (10 patients), with age/gender-matched healthy controls (10 control subjects).

Twenty-seven gene transcripts were increased 1.5- to sixfold and six decreased three- to sixfold in the patient group (P < 0.01). The top enhanced gene transcripts, IL8, NFΚBIA and TNFAIP3, are functionally related to inflammation, and significant changes were validated for IL8 and NFΚBIA by quantitative polymerase chain reaction (qPCR).

Functional network analysis of the altered gene transcripts (P < 0.01) detected interactions between the products related to inflammation, circadian clock function, metabolic dysregulation, cellular stress responses and mitochondrial function. Ingenuity pathway analysis (P < 0.05) provided further insights into the dysfunctional physiology, highlighting stress and inflammation pathways.

This analysis provides novel insights into the molecular changes in ME/CFS and contributes to the understanding of the pathophysiological mechanisms of the disease.

From the conclusion:

Our exploratory approach has enabled us to obtain a rich differentially expressed gene dataset to identify changed biology in ME/CFS. We have identified the circadian rhythm dysregulation pathway as a new possible underlying cause of the unrefreshing sleep, fatigue and metabolic abnormalities seen in ME/CFS. Furthermore, impaired mitochondrial function and resulting oxidative stress, coupled with chronic immune-inflammatory signalling, provides a compelling explanation for the fatigue, cognitive dysfunction and post-exertion malaise experienced in ME/CFS.

Therefore, this study is a further step towards gaining an understanding of the disease process and identifying putative biomarkers to support clinical diagnosis. The biological pathways identified offer a rational explanation of the complex and often multi-systemic nature of ME/CFS.

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A compromised paraventricular nucleus within a dysfunctional hypothalamus: A novel neuroinflammatory paradigm for ME/CFS

A compromised paraventricular nucleus within a dysfunctional hypothalamus: A novel neuroinflammatory paradigm for ME/CFS, by Angus Mackay, Warren P Tate in International Journal of Immunopathology and Pharmacology Vol: 32 [published online: December 6, 2018]

 

Article abstract: 
A neuroinflammatory paradigm is presented to help explain the pathophysiology of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

The hypothalamic paraventricular nucleus (PVN) is responsible for absorbing and processing multiple, incoming and convergent ‘stress’ signals, and if this cluster of neurons were affected (by neuroinflammation), the ongoing hypersensitivity of ME/CFS patients to a wide range of ‘stressors’ could be explained.

Neuroinflammation that was chronic and fluctuating, as ‘inflammatory-marker’ studies support, could reflect a dynamic change in the hypothalamic PVN’s threshold for managing incoming ‘stress’ signals. This may not only be a mechanism underpinning the characteristic feature of ME/CFS, post-exertional malaise, and its associated debilitating relapses, but could also be responsible for mediating the long-term perpetuation of the disease.

Triggers (sustained physiological ‘stressors’) of ME/CFS, such as a particular viral infection, toxin exposure, or a traumatic event, could also target the hypothalamic PVN, a potentially vulnerable site in the brains of ME/CFS susceptible people, and disruption of its complex neural circuitry could account for the onset of ME/CFS.

In common with the different ‘endogenous factors’ identified in the early ‘neuroinflammatory’ stages of the ‘neurodegenerative’ diseases, an as yet, unidentified factor within the brains and central nervous system (CNS) of ME/CFS patients might induce both an initial and then sustained ‘neuroinflammatory’ response by its ‘innate immune system’.  Positron emission tomography/magnetic resonance imaging has reinforced evidence of glial cell activation centred on the brain’s limbic system of ME/CFS patients.

Neuroinflammation causing dysfunction of the limbic system and its hypothalamus together with a consequently disrupted autonomic nervous system could account for the diverse range of symptoms in ME/CFS relating, in particular to fatigue, mood, cognitive function, sleep, thermostatic control, gastrointestinal disturbance, and hypotension.

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Estimating prevalence, demographics & costs of ME/CFS using large scale medical claims data & Machine Learning (US)

Estimating prevalence, demographics and costs of ME/CFS using large scale medical claims data and machine learning, by Ashley Valdez, Elizabeth E. Hancock, Seyi Adebayo, David Kiernicki, Daniel Proskauer, John R. Attewell, Lucinda Bateman, Alfred DeMaria, Jr, Charles W. Lapp, Peter C. Rowe and Charmian Proskauer in Front. Pediatr. 08 January 2019

Research abstract:
Techniques of data mining and machine learning were applied to a large database of medical and facility claims from commercially insured patients to determine the prevalence, gender demographics, and costs for individuals with provider-assigned diagnosis codes for myalgic encephalomyelitis (ME) or chronic fatigue syndrome (CFS).

The frequency of diagnosis was 519 – 1,038/100,000 with the relative risk of females being diagnosed with ME or CFS compared to males 1.238 and 1.178, respectively. While the percentage of women diagnosed with ME/CFS is higher than the percentage of men, ME/CFS is not a “woman’s disease.” Thirty-five to forty percent of diagnosed patients are men.

Extrapolating from this frequency of diagnosis and based on the estimated 2017 population of the United States, a rough estimate for the number of patients who may be diagnosed with ME or CFS in the U.S. is 1.7 million to 3.38 million.

Patients diagnosed with CFS appear to represent a more heterogeneous group than those diagnosed with ME. A machine learning model based on characteristics of individuals diagnosed with ME was developed and applied, resulting in a predicted prevalence of 857/100,000 (p>0.01), or roughly 2.8 million in the U.S.

Average annual costs for individuals with a diagnosis of ME or CFS were compared with those for lupus (all categories) and multiple sclerosis (MS), and found to be 50% higher for ME and CFS than for lupus or MS, and three to four times higher than for the general insured population.

A separate aspect of the study attempted to determine if a diagnosis of ME or CFS could be predicted based on symptom codes in the insurance claims records. Due to the absence of specific codes for some core symptoms, we were unable to validate that the information in insurance claims records is sufficient to identify diagnosed patients or suggest that a diagnosis of ME or CFS should be considered based solely on looking for presence of those symptoms.

These results show that a prevalence rate of 857/100,000 for ME/CFS is not unreasonable; therefore, it is not a rare disease, but in fact a relatively common one.

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Initiating care of a patient with ME/CFS

Initiating care of a patient with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), by Charles W. Lapp in Front. Pediatr., [Published 23 January 2019]

 

Article abstract:
This paper introduces the primary care physician to the unique and challenging aspects of initially diagnosing and managing a complex condition for which there are a plethora of symptoms, few physical findings, no known cause, and no specific treatments. While daunting, the rewards are many, and those who pursue an interest in ME/CFS find themselves at the forefront of medicine.

The approach to any complex problem is to break it down into small steps, and ME/CFS is no exception. The first office visit should be devoted to a history of the present illness, a physical examination, and collection of exclusionary laboratory tests. On follow-up the differential diagnosis and a treatment plan can be addressed. Many individuals with ME/CFS have been humiliated or dismissed by other providers, so one will need to be as non-judgmental as possible and acknowledge that ME/CFS is not a psychological condition but a real illness. They need reassurance that you will work with them to seek a unifying diagnosis and prioritize management.

Management

Many patients will be seeking rapid relief and even a cure for their illness, but foremost they must have realistic expectations: ME/CFS is a chronic illness for which there is currently no known cure. Nevertheless, there are many treatments that can be helpful to reduce symptoms and improve functionality.

Most experts would agree (9) that it is most important to address exertion intolerance and post-exertional malaise first; then sleep and pain, followed by cognition and the co-morbidities. Experts will agree that patients must avoid over-exerting and then flaring or relapsing—referred to as “pushing and crashing”—which clearly exacerbates the illness and hinders improvement. The controversy surrounds how to best prevent that.

One technique is interval activity or time-based activity. If an individual knows that they can be active for a period of time without triggering symptoms—say 15 min—then he or she can shop or work for 15 min, take a break, then shop or work for another 15 min, and so on. Over time, the activity interval can be increased (10).

Another technique is to monitor steps per day by wearing a step meter or pedometer (11). It is important for patients to take at least 1,000 steps per day in order to avoid deconditioning; but patients are encouraged to calculate their average steps per day during a good week with no flares or relapses. This is typically about 2,500–3,500 steps per day. They are then encouraged to not exceed that number of steps. So if a patient went shopping or sightseeing one day and reached her average limit of 3,500 steps, she would know to quit and rest as soon as possible to avoid a flare or relapse.

Scientific evidence is mounting that patients should not exceed their Anaerobic Threshold, an activity level at which the heart and lungs cannot supply enough oxygen to the mitochondria. In the absence of oxygen, glucose metabolism is much less efficient and produces lactic acid and other toxins that seem detrimental to our patients. The Anaerobic Threshold is usually determined by specialized exercise testing, but is related to one’s heart rate. So if a patient can monitor heart rate, he or she can estimate the maximum heart rate (frequently under 110 in adults) that can be tolerated without triggering a flare. Then avoid exceeding that heart rate except for short periods (12).

In short, it is very important to balance any activity with generous amounts of rest. So the patient should be encouraged to remain active, but not so active as to trigger flares and relapses.

Sleep is the next most important area to address. Start with typical sleep hygiene principles. Patients may consider over-the-counter sleep aids such as melatonin, theanine, valerian, tryptophan, antihistamines (diphenhydramine, doxylamine), or proprietary sleep aids. Low dose tricyclic or tetracyclic antidepressants, cyclobenzaprine, or low dose tizanidine are frequently prescribed to maintain sleep. If necessary, consider prescribing the usual benzodiazepine -based sleep medications to initiate sleep. Between 18 and 62% of persons with ME/CFS have primary sleep disorders, so highly consider referral to a sleep specialist if a sleep disorder is suspected (13).

Pain is another major symptom to address as it may affect sleep, mood, mobility and other domains. First identify the sources of pain: Fibromyalgia? Myofascial pain? Headache? Arthralgia? Inflammatory joint pain? Then assess the patient’s need for pain intervention. Will non-pharmacologic therapy suffice such as hot packs, cold packs, liniments, baths or showers, massage, chiropractic, acupuncture, or TENS? If pharmacologic therapy is indicated, have non-opioid therapies been tried such as Cymbalta/duloxetine, Savella/milnacipran, or Lyrica/pregabalin? (7) In the last 10 years Low Dose Naltrexone has become a primary consideration in opioid-naïve individuals (14). If opioid medications are indicated, tramadol has been very effective, but many providers would be most comfortable referring to a pain specialist for anything more potent. In the case of migraine or rheumatic pain, specialists might also be indicated.

Cognitive problems tend to wax and wane, much as fatigue does. Patients need to be reassured that they are not developing Alzheimer’s or dementia, and there is no evidence that such cognitive losses are permanent. While medication has helped little to improve cognition, the provider can suggest helpful techniques such as:

  • Keep a calendar, notebook and calculator at hand.
  • Always carry a cell phone to call for assistance, use as a GPS, or photograph your location in a parking lot or unfamiliar area.
  • Develop the habit of always putting up important items such as keys, purses, wallets, and glasses in the same place.
  • Plan important tasks to be done during the “best time of your day.”
  • Avoid chaotic, stressful, or multisensory situations or events.

Autonomic, (auto)immune, (neuro)endocrine, psychological and co-morbid issues are managed as you would normally in your medical practice. It is imperative to address co-morbidities because they confound the ME/CFS. Consultants may be required. It is very important not to attribute all new symptoms to ME/CFS alone. Lastly, patients must maintain adequate hydration and nutrition although they tend to neglect these areas due to fatigue.

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Neuroinflammation & cytokines in ME/CFS: a critical review of research methods

Neuroinflammation and  cytokines in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a critical review of research methods, by Michael B VanElzakker, Sydney A. Brumfield and Paula S. Lara Mejia in Front. Neurol., 10 January 2019

Review article abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is the label given to a syndrome that can include long-term flu-like symptoms, profound fatigue, trouble concentrating, and autonomic problems, all of which worsen after exertion. It is unclear how many individuals with this diagnosis are suffering from the same condition or have the same underlying pathophysiology, and the discovery of biomarkers would be clarifying.

The name “myalgic encephalomyelitis” essentially means “muscle pain related to central nervous system inflammation” and many efforts to find diagnostic biomarkers have focused on one or more aspects of neuroinflammation, from periphery to brain. As the field uncovers the relationship between the symptoms of this condition and neuroinflammation, attention must be paid to the biological mechanisms of neuroinflammation and issues with its potential measurement.

The current review focuses on three methods used to study putative neuroinflammation in ME/CFS:

  1. positron emission tomography (PET) neuroimaging using translocator protein (TSPO) binding radioligand
  2. magnetic resonance spectroscopy (MRS) neuroimaging and
  3. assays of cytokines circulating in blood and cerebrospinal fluid.

PET scanning using TSPO-binding radioligand is a promising option for studies of neuroinflammation. However, methodological difficulties that exist both in this particular technique and across the ME/CFS neuroimaging literature must be addressed for any results to be interpretable.

We argue that the vast majority of ME/CFS neuroimaging has failed to use optimal techniques for studying brainstem, despite its probable centrality to any neuroinflammatory causes or autonomic effects.

MRS is discussed as a less informative but more widely available, less invasive, and less expensive option for imaging neuroinflammation, and existing studies using MRS neuroimaging are reviewed.

Studies seeking to find a peripheral circulating cytokine “profile” for ME/CFS are reviewed, with attention paid to the biological and methodological reasons for lack of replication among these studies. We argue that both the biological mechanisms of cytokines and the innumerable sources of potential variance in their measurement make it unlikely that a consistent and replicable diagnostic cytokine profile will ever be discovered.

 

#MEAction: Neuroinflammation review by #MEAction research fellows

 

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