[Myalgic encephalomyelitis : etiopathogenesis, diagnosis and treatment]. / Encéphalomyélite myalgique : étiopathogénie, diagnostic et traitement.

Myalgic encephalomyelitis (ME), also known as chronic fatigue syndrome (CFS), is a neurological disorder involving multiple pathophysiological mechanisms and etiologies. Symptoms include asthenia, myalgia, post-exertional malaise and neurocognitive disorders. While the numerous patient complaints pose a diagnostic challenge, the advent of new technologies paves the way for innovative methods to reveal ME. The heterogeneity of the disease's mechanisms complicates the search for effective treatments but also offers the prospect of numerous beneficial molecules. Combining treatments targeting mitochondrial dysfunction, oxidative stress, inflammation and immunological disorders appears to be the current optimal therapeutic approach.

L'encéphalomyélite myalgique (EM), aussi connue sous le nom de syndrome de fatigue chronique (SFC), est une maladie neurologique impliquant des mécanismes physiopathologiques et des étiologies multiples. Les symptômes comprennent une asthénie, des myalgies, un malaise après effort et des troubles neurocognitifs. Si les nombreuses plaintes des patients représentent un défi diagnostique, l'apparition de nouvelles technologies ouvre la voie à des méthodes novatrices pour révéler l'EM. L'hétérogénéité des mécanismes de la maladie complique la recherche de traitements efficaces mais offre également la perspective de nombreuses molécules bénéfiques. Associer des traitements ciblant le dysfonctionnement mitochondrial, le stress oxydatif, l'inflammation et les troubles immunologiques semble être la meilleure démarche thérapeutique actuelle.

What are medical students taught about persistent physical symptoms? A scoping review of the literature.

BACKGROUND: Persistent Physical Symptoms (PPS) include symptoms such as chronic pain, and syndromes such as chronic fatigue. They are common, but are often inadequately managed, causing distress and higher costs for health care systems. A lack of teaching about PPS has been recognised as a contributing factor to poor management. METHODS: The authors conducted a scoping review of the literature, including all studies published before 31 March 2023. Systematic methods were used to determine what teaching on PPS was taking place for medical undergraduates. Studies were restricted to publications in English and needed to include undergraduate medical students. Teaching about cancer pain was excluded. After descriptive data was extracted, a narrative synthesis was undertaken to analyse qualitative findings. RESULTS: A total of 1116 studies were found, after exclusion, from 3 databases. A further 28 studies were found by searching the grey literature and by citation analysis. After screening for relevance, a total of 57 studies were included in the review. The most commonly taught condition was chronic non-cancer pain, but overall, there was a widespread lack of teaching and learning on PPS. Several factors contributed to this lack including: educators and learners viewing the topic as awkward, learners feeling that there was no science behind the symptoms, and the topic being overlooked in the taught curriculum. The gap between the taught curriculum and learners' experiences in practice was addressed through informal sources and this risked stigmatising attitudes towards sufferers of PPS. CONCLUSION: Faculties need to find ways to integrate more teaching on PPS and address the barriers outlined above. Teaching on chronic non-cancer pain, which is built on a science of symptoms, can be used as an exemplar for teaching on PPS more widely. Any future teaching interventions should be robustly evaluated to ensure improvements for learners and patients.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: the biology of a neglected disease.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a chronic, debilitating disease characterised by a wide range of symptoms that severely impact all aspects of life. Despite its significant prevalence, ME/CFS remains one of the most understudied and misunderstood conditions in modern medicine. ME/CFS lacks standardised diagnostic criteria owing to variations in both inclusion and exclusion criteria across different diagnostic guidelines, and furthermore, there are currently no effective treatments available. Moving beyond the traditional fragmented perspectives that have limited our understanding and management of the disease, our analysis of current information on ME/CFS represents a significant paradigm shift by synthesising the disease's multifactorial origins into a cohesive model. We discuss how ME/CFS emerges from an intricate web of genetic vulnerabilities and environmental triggers, notably viral infections, leading to a complex series of pathological responses including immune dysregulation, chronic inflammation, gut dysbiosis, and metabolic disturbances. This comprehensive model not only advances our understanding of ME/CFS's pathophysiology but also opens new avenues for research and potential therapeutic strategies. By integrating these disparate elements, our work emphasises the necessity of a holistic approach to diagnosing, researching, and treating ME/CFS, urging the scientific community to reconsider the disease's complexity and the multifaceted approach required for its study and management.

A systematic review of quantitative EEG findings in Fibromyalgia, Chronic Fatigue Syndrome and Long COVID.

Fibromyalgia Syndrome (FMS), Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long COVID (LC) are similar multisymptom clinical syndromes but with difference in dominant symptoms in each individual. There is existing and emerging literature on possible functional alterations of the central nervous system in these conditions. This review aims to synthesise and appraise the literature on resting-state quantitative EEG (qEEG) in FMS, ME/CFS and LC, drawing on previous research on FMS and ME/CFS to help understand neuropathophysiology of the new condition LC. A systematic search of MEDLINE, Embase, CINHAL, PsycINFO and Web of Science databases for articles published between December 1994 and September 2023 was performed. Out of the initial 2510 studies identified, 17 articles were retrieved that met all the predetermined selection criteria, particularly of assessing qEEG changes in one of the three conditions compared to healthy controls. All studies scored moderate to high quality on the Newcastle-Ottawa scale. There was a general trend for decreased low-frequency EEG band activity (delta, theta, and alpha) and increased high-frequency EEG beta activity in FMS, differing to that found in ME/CFS. The limited LC studies included in this review focused mainly on cognitive impairments and showed mixed findings not consistent with patterns observed in FMS and ME/CFS. Our findings suggest different patterns of qEEG brainwave activity in FMS and ME/CFS. Further research is required to explore whether there are phenotypes within LC that have EEG signatures similar to FMS or ME/CFS. This could inform identification of reliable diagnostic markers and possible targets for neuromodulation therapies tailored to each clinical syndrome.

Learning points about myalgic encephalomyelitis/chronic fatigue syndrome: Bridging the gap between research, clinical practice and awareness.

This essay examines the complex landscape of myalgic encephalomyelitis, commonly known as chronic fatigue syndrome, highlighting its chronic and multisystemic nature with elusive causative factors. It discusses clinical challenges in diagnosis and management, emphasising the importance of increased education and awareness among healthcare professionals. The role of empathic, person-centred care in improving patient outcomes is underscored, urging for a paradigm shift towards understanding and addressing the profound impact of myalgic encephalitis/chronic fatigue syndrome on patients' lives.

[Interdisciplinary, collaborative D-A-CH (Germany, Austria and Switzerland) consensus statement concerning the diagnostic and treatment of myalgic encephalomyelitis/chronic fatigue syndrome]. / Interdisziplinäres, kollaboratives D-A-CH Konsensus-Statement zur Diagnostik und Behandlung von Myalgischer Enzephalomyelitis/Chronischem Fatigue-Syndrom.

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a severe, chronic multisystemic disease which, depending on its severity, can lead to considerable physical and cognitive impairment, loss of ability to work and the need for nursing care including artificial nutrition and, in very severe cases, even death.The aim of this D-A-CH (Germany, Austria, Switzerland) consensus statement is 1) to summarize the current state of knowledge on ME/CFS, 2) to highlight the Canadian Consensus Criteria (CCC) as clinical criteria for diagnostics with a focus on the leading symptom post-exertional malaise (PEM) and 3) to provide an overview of current options and possible future developments, particularly with regard to diagnostics and therapy. The D-A-CH consensus statement is intended to support physicians, therapists and valuer in diagnosing patients with suspected ME/CFS by means of adequate anamnesis and clinical-physical examinations as well as the recommended clinical CCC, using the questionnaires and other examination methods presented. The overview of the two pillars of therapy for ME/CFS, pacing and symptom-relieving therapy options, is intended not only to provide orientation for physicians and therapists, but also to support decision-makers from healthcare policy and insurance companies in determining which therapy options should already be reimbursable by them at this point in time for the indication ME/CFS.

Factors associated with having previously received a diagnosis of fibromyalgia, chronic fatigue syndrome and irritable bowel syndrome: A cross sectional DanFunD study.

OBJECTIVES: Fibromyalgia, chronic fatigue syndrome, and irritable bowel syndrome are highly prevalent conditions and part of the functional somatic syndromes (FSS) diagnosis, that are classified under the unifying umbrella term functional somatic disorder (FSD). Multiple factors are associated with FSD symptom development; However, few studies have explored these associations in relation to the diagnosis status. This study aims to examine associations with a previously received FSS diagnosis from a physician in participants fulfilling the FSD diagnostic criteria in a population-based sample. METHODS: This research employs a comprehensive observational approach using a cross sectional design with data from the DanFunD part two cohort. Information about received FSS diagnoses was obtained from self-reported questionnaires. Participants fulfilling the FSD diagnostic criteria were identified with both self-reported questionnaires and diagnostic interviews. Validated questionnaires were used to assess the examined factors. RESULTS: 1704 cases fulfilled the diagnostic criteria for an FSD according to questionnaires or interviews in the DanFunD study. In participants fulfilling the diagnostic criteria, having previously received an FSS diagnosis by a physician was strongly associated with female sex, negative illness perceptions and poor health-related quality of life for questionnaire and interview-based diagnoses. Less consistent associations were observed for lower socioeconomic status, anxiety, and adverse life events. CONCLUSION: Previously received FSS diagnoses showed associations with multiple factors with a particular strong association with female sex and poor health related quality of life.

Validity and diagnostic overlap of functional somatic syndrome diagnoses.

OBJECTIVE: We present the first study that investigates the validity and the diagnostic overlap of the three main functional somatic syndrome (FSS) diagnoses, i.e. chronic fatigue syndrome (CFS), fibromyalgia (FM), and irritable bowel syndrome (IBS), irrespective of help-seeking behaviour or diagnostic habits, and irrespective of differences in diagnostic thresholds for chronicity or symptom interference. METHODS: This cross-sectional analysis was performed in 89,781 participants of the general-population cohort Lifelines. Diagnostic criteria for CFS (Centers for Disease Control and Prevention), FM (American College of Rheumatology) and IBS (Rome IV) were assessed by questionnaire. Additional items were added to enable studying the effects of differences in thresholds for minimum symptom chronicity (varying from three for FM to six months for CFS and IBS), and symptom interference (required for CFS but not for FM and IBS). RESULTS: The diagnostic criteria were met by 3.1% for CFS, 6.6% for FM, and 5.5% for IBS participants. The number of participants that met criteria for all three diagnoses was 45 times higher than what would have been expected based on chance. After alignment of the chronicity and symptom interference criteria to circumvent differences in diagnostic thresholds, the overlap between diagnoses increased to 152 times. Furthermore, there was a similar pattern of symptom occurrence, particularly for those fulfilling diagnostic criteria for CFS and FM. CONCLUSION: The diagnostic overlap of different FSS was much higher than would be expected by chance, and substantially increased when FSS were more chronic and serious in nature.

IA-PACS-CFS: a double-blinded, randomized, sham-controlled, exploratory trial of immunoadsorption in patients with chronic fatigue syndrome (CFS) including patients with post-acute COVID-19 CFS (PACS-CFS).

BACKGROUND: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a severely debilitating condition which markedly restricts activity and function of affected people. Since the beginning of the COVID-19 pandemic ME/CFS related to post-acute COVID-19 syndrome (PACS) can be diagnosed in a subset of patients presenting with persistent fatigue 6 months after a mostly mild SARS-CoV-2 infection by fulfillment of the Canadian Consensus Criteria (CCC 2003). Induction of autoimmunity after viral infection is a mechanism under intensive investigation. In patients with ME/CFS, autoantibodies against thyreoperoxidase (TPO), beta-adrenergic receptors (ß2AR), and muscarinic acetylcholine receptors (MAR) are frequently found, and there is evidence for effectiveness of immunomodulation with B cell depleting therapy, cyclophosphamide, or intravenous immunoglobulins (IVIG). Preliminary studies on the treatment of ME/CFS patients with immunoadsorption (IA), an apheresis that removes antibodies from plasma, suggest clinical improvement. However, evidence from placebo-controlled trials is currently missing. METHODS: In this double-blinded, randomized, sham-controlled, exploratory trial the therapeutic effect of five cycles of IA every other day in patients with ME/CFS, including patients with post-acute COVID-19 chronic fatigue syndrome (PACS-CFS), will be evaluated using the validated Chalder Fatigue Scale, a patient-reported outcome measurement. A total of 66 patients will be randomized at a 2:1 ratio: 44 patients will receive IA (active treatment group) and 22 patients will receive a sham apheresis (control group). Moreover, safety, tolerability, and the effect of IA on patient-reported outcome parameters, biomarker-related objectives, cognitive outcome measurements, and physical parameters will be assessed. Patients will be hospitalized at the clinical site from day 1 to day 10 to receive five IA treatments and medical visits. Four follow-up visits (including two visits at site and two visits via telephone call) at month 1 (day 30), 2 (day 60), 4 (day 120), and 6 (day 180; EOS, end of study visit) will take place. DISCUSSION: Although ME/CFS including PACS-CFS causes an immense individual, social, and economic burden, we lack efficient therapeutic options. The present study aims to investigate the efficacy of immunoadsorption and to contribute to the etiological understanding and establishment of diagnostic tools for ME/CFS. TRIAL REGISTRATION: Registration Number: NCT05710770 . Registered on 02 February 2023.

Myalgic encephalomyelitis/chronic fatigue syndrome from current evidence to new diagnostic perspectives through skeletal muscle and metabolic disturbances.

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a demanding medical condition for patients and society. It has raised much more public awareness after the COVID-19 pandemic since ME/CFS and long-COVID patients share many clinical symptoms such as debilitating chronic fatigue. However, unlike long COVID, the etiopathology of ME/CFS remains a mystery despite several decades' research. This review moves from pathophysiology of ME/CFS through the compelling evidence and most interesting hypotheses. It focuses on the pathophysiology of skeletal muscle by proposing the hypothesis that skeletal muscle tissue offers novel opportunities for diagnosis and treatment of this syndrome and that new evidence can help resolve the long-standing debate on terminology.

Association between fatigue, peripheral serotonin, and L-carnitine in hypothyroidism and in chronic fatigue syndrome.

Background: Fatigue of unknown origin is a hallmark symptom in chronic fatigue syndrome (CFS) and is also found in 20% of hypothyroidism patients despite appropriate levothyroxine treatment. Here, we suggest that in these disorders, peripheral serotonin levels are low, and elevating them to normal range with L-carnitine is accompanied with reduced fatigue. Methods: We conducted a retrospective analysis of follow-up clinical data (CFS N=12; hypothyroidism with fatigue N=40) where serum serotonin and fatigue levels were compared before vs. after 7 weeks of oral L-carnitine supplementation. Results: After L-carnitine, serotonin increased (8-fold in CFS, Sig. = 0.002, 6-fold in hypothyroidism, Sig. < 0.001) whereas fatigue decreased (2-fold in both CFS and hypothyroidism, Sig. = 0.002 for CFS, Sig. < 0.001 for hypothyroidism). There was a negative correlation between serotonin level and fatigue (for CFS, rho = -0.49 before and -0.67 after L-carnitine; for hypothyroidism, rho = -0.24 before and -0.83 after L-carnitine). Conclusions: These findings suggest a new link between low peripheral serotonin, L-carnitine, and fatigue.

NIH Study Provides Long-Awaited Insight Into Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

This Medical News article discusses a new US National Institutes of Health study of patients with the chronic­and chronically misunderstood­disease.

Management of severe ME/CFS in children and young people in the UK: a British Paediatric Surveillance Unit study.

OBJECTIVE: Severe myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) in children and young people (CYP) is a little-understood condition which significantly impacts education, development and quality of life. We used data from a population-wide surveillance study to explore the screening investigation, referral and management of suspected cases of paediatric severe ME/CFS. METHODS: A British Paediatric Surveillance Unit (BPSU) study reported cases of CYP with suspected severe ME/CFS between February 2018 and February 2019. Paediatricians reporting cases to BPSU and allied healthcare professionals in two large specialist paediatric ME/CFS centres were invited to complete questionnaires for CYP meeting the surveillance case definition. The study focused primarily on CYP with confirmed severe ME/CFS and the extent to which their care met NICE (The National Institute for Health and Care Excellence) recommendations but also considered separately those with probable or possible severe ME/CFS. RESULTS: This study includes a total of 92 CYP with suspected severe ME/CFS; 33 meeting criteria for severe ME/CFS and an additional 59 classified as probable or possible severe ME/CFS. For 16 possible cases, incomplete investigation to exclude alternative diagnoses prevented confirmation of a severe ME/CFS diagnosis. Only 21 of 33 (64%) confirmed severe ME/CFS cases had been referred to specialist services. The management provided varied considerably between patients and four received nothing at all. Of the management provided, the most frequent approaches were medication (67%), activity management (61%) and physiotherapy (61%). Domiciliary assessments and support, and social services referrals were received by 12% and 6% of confirmed severe cases. Similar proportions of management approaches were seen in probable/possible severe ME/CFS. CONCLUSION: Full investigation is frequently incomplete in CYP with suspected severe ME/CFS and recommendations for referral and management are poorly implemented, in particular the needs of CYP who are unable to leave their home might be poorly met.

NICE guideline on ME/CFS: robust advice based on a thorough review of the evidence.

In 2021, the National Institute for Health and Care Excellence produced an evidence-based guideline on the diagnosis and management of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), a disabling long-term condition of unknown cause. The guideline provides clear support for people living with ME/CFS, their families and carers, and for clinicians. A recent opinion piece published in the journal suggested that there were anomalies in the processing and interpretation of the evidence when developing the guideline and proposed eight areas where these anomalies were thought to have occurred. We outline how these opinions are based on a misreading or misunderstanding of the guideline process or the guideline, which provides a balanced and reasoned approach to the diagnosis and management of this challenging condition.

Fatigue and symptom-based clusters in post COVID-19 patients: a multicentre, prospective, observational cohort study.

BACKGROUND: In the Netherlands, the prevalence of post COVID-19 condition is estimated at 12.7% at 90-150 days after SARS-CoV-2 infection. This study aimed to determine the occurrence of fatigue and other symptoms, to assess how many patients meet the Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) criteria, to identify symptom-based clusters within the P4O2 COVID-19 cohort and to compare these clusters with clusters in a ME/CFS cohort. METHODS: In this multicentre, prospective, observational cohort in the Netherlands, 95 post COVID-19 patients aged 40-65 years were included. Data collection at 3-6 months after infection included demographics, medical history, questionnaires, and a medical examination. Follow-up assessments occurred 9-12 months later, where the same data were collected. Fatigue was determined with the Fatigue Severity Scale (FSS), a score of ≥ 4 means moderate to high fatigue. The frequency and severity of other symptoms and the percentage of patients that meet the ME/CFS criteria were assessed using the DePaul Symptom Questionnaire-2 (DSQ-2). A self-organizing map was used to visualize the clustering of patients based on severity and frequency of 79 symptoms. In a previous study, 337 Dutch ME/CFS patients were clustered based on their symptom scores. The symptom scores of post COVID-19 patients were applied to these clusters to examine whether the same or different clusters were found. RESULTS: According to the FSS, fatigue was reported by 75.9% of the patients at 3-6 months after infection and by 57.1% of the patients 9-12 months later. Post-exertional malaise, sleep disturbances, pain, and neurocognitive symptoms were also frequently reported, according to the DSQ-2. Over half of the patients (52.7%) met the Fukuda criteria for ME/CFS, while fewer patients met other ME/CFS definitions. Clustering revealed specific symptom patterns and showed that post COVID-19 patients occurred in 11 of the clusters that have been observed in the ME/CFS cohort, where 2 clusters had > 10 patients. CONCLUSIONS: This study shows persistent fatigue and diverse symptomatology in post COVID-19 patients, up to 12-18 months after SARS-CoV-2 infection. Clustering showed that post COVID-19 patients occurred in 11 of the clusters that have been observed in the ME/CFS cohort.

Joint Flexibility and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome After Mononucleosis.

PURPOSE: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic disease characterized by substantial fatigue, postexertional malaise, unrefreshing sleep, and orthostatic intolerance, among other symptoms. Specific risk factors for the development of ME/CFS have not been adequately characterized. It has been suggested that ME/CFS is a connective tissue disorder and that joint hyperflexibility is a risk factor for the development of ME/CFS. METHODS: The goal of this study was to examine whether joint hyperflexibility is a risk factor for the development of ME/CFS after infectious mononucleosis (IM). This study was part of a prospective cohort study. College students were studied for the development of IM and were followed up for the development of ME/CFS 6 months later. Participants in the cohort for the present study included 53 students who met criteria for ME/CFS 6 months after IM and 66 recovered control subjects who had modified Beighton scores (a measure of joint hyperflexibility) available. FINDINGS: No connection was found between joint hyperflexibility and the development of ME/CFS after IM. Differences in joint hyperflexibility (as measured by using the modified Beighton score) in the ME/CFS group and the control group were not statistically significant. Female subjects had significantly higher Beighton scores compared with male subjects. IMPLICATION: After IM, no relationship was found between joint hyperflexibility and the development of ME/CFS.

IgG Antibody Responses to Epstein-Barr Virus in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Their Effective Potential for Disease Diagnosis and Pathological Antigenic Mimicry.

Background and Objectives: The diagnosis and pathology of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) remain under debate. However, there is a growing body of evidence for an autoimmune component in ME/CFS caused by the Epstein-Barr virus (EBV) and other viral infections. Materials and Methods: In this work, we analyzed a large public dataset on the IgG antibodies to 3054 EBV peptides to understand whether these immune responses could help diagnose patients and trigger pathological autoimmunity; we used healthy controls (HCs) as a comparator cohort. Subsequently, we aimed at predicting the disease status of the study participants using a super learner algorithm targeting an accuracy of 85% when splitting data into train and test datasets. Results: When we compared the data of all ME/CFS patients or the data of a subgroup of those patients with non-infectious or unknown disease triggers to the data of the HC, we could not find an antibody-based classifier that would meet the desired accuracy in the test dataset. However, we could identify a 26-antibody classifier that could distinguish ME/CFS patients with an infectious disease trigger from the HCs with 100% and 90% accuracies in the train and test sets, respectively. We finally performed a bioinformatic analysis of the EBV peptides associated with these 26 antibodies. We found no correlation between the importance metric of the selected antibodies in the classifier and the maximal sequence homology between human proteins and each EBV peptide recognized by these antibodies. Conclusions: In conclusion, these 26 antibodies against EBV have an effective potential for disease diagnosis in a subset of patients. However, the peptides associated with these antibodies are less likely to induce autoimmune B-cell responses that could explain the pathogenesis of ME/CFS.