Myalgic encephalomyelitis--a persistent enteroviral infection?

Development of a Management App for Postviral Fibromyalgia-Like Symptoms: Patient Preference-Guided Approach

BACKGROUND

Persistent fibromyalgia-like symptoms have been increasingly reported following viral infections, including SARS-CoV-2. About 30% of patients with post-COVID-19 syndrome fulfill the fibromyalgia criteria. This complex condition presents significant challenges in terms of self-management. Digital health interventions offer a viable means to assist patients in managing their health conditions. However, the challenge of ensuring their widespread adoption and adherence persists. This study responds to this need by developing a patient-centered digital health management app, incorporating patient preferences to enhance usability and effectiveness, ultimately aiming to improve patient outcomes and quality of life.

OBJECTIVE

This research aims to develop a digital health self-management app specifically for patients experiencing postviral fibromyalgia-like symptoms. By prioritizing patient preferences and engagement through the app's design and functionality, the study intends to facilitate better self-management practices and improve adherence.

METHODS

Using an exploratory study design, the research used patient preference surveys and usability testing as primary tools to inform the development process of the digital health solution. We gathered and analyzed patients' expectations regarding design features, content, and usability to steer the iterative app development.

RESULTS

The study uncovered crucial insights from patient surveys and usability testing, which influenced the app's design and functionality. Key findings included a preference for a symptom list over an automated chatbot, a desire to report on a moderate range of symptoms and activities, and the importance of an intuitive onboarding process. While usability testing identified some challenges in the onboarding process, it also confirmed the importance of aligning the app with patient needs to enhance engagement and satisfaction.

CONCLUSIONS

Incorporating patient feedback has been a significant factor in the development of the digital health app. Challenges encountered with user onboarding during usability testing have highlighted the importance of this process for user adoption. The study acknowledges the role of patient input in developing digital health technologies and suggests further research to improve onboarding procedures, aiming to enhance patient engagement and their ability to manage digital health resources effectively.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/32193.

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.

Mechanisms, Effects, and Management of Neurological Complications of Post-Acute Sequelae of COVID-19 (NC-PASC)

With a growing number of patients entering the recovery phase following infection with SARS-CoV-2, understanding the long-term neurological consequences of the disease is important to their care. The neurological complications of post-acute sequelae of SARS-CoV-2 infection (NC-PASC) represent a myriad of symptoms including headaches, brain fog, numbness/tingling, and other neurological symptoms that many people report long after their acute infection has resolved. Emerging reports are being published concerning COVID-19 and its chronic effects, yet limited knowledge of disease mechanisms has challenged therapeutic efforts. To address these issues, we review broadly the literature spanning 2020-2022 concerning the proposed mechanisms underlying NC-PASC, outline the long-term neurological sequelae associated with COVID-19, and discuss potential clinical interventions.

Patient perceptions of infectious illnesses preceding Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

OBJECTIVES

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is often reported to be caused by an infectious agent. However, it is unclear whether one infectious agent might be the cause or whether there might be many different infectious agents. The objective of this study was to identify self-reported infectious illnesses associated with the onset of ME/CFS.

METHODS

The present study involved data from multiple sites in several countries. 1773 individuals diagnosed with either ME, CFS or ME/CFS provided qualitative data concerning infectious triggers which were coded and classified for analysis.

RESULTS

60.3% of patients report a variety of infectious illnesses some time before onset of ME/CFS. The most frequently reported infectious illness was Mononucleosis, which occurred in 30% of infections. However, over 100 other infectious illnesses were mentioned.

DISCUSSION

The findings suggest that many infectious agents might be associated with the onset of ME/CFS.

An mHealth App for Fibromyalgia-like Post-COVID-19 Syndrome: Protocol for the Analysis of User Experience and Clinical Data

Background

Post–COVID-19 syndrome, also referred as “long covid,” describes persisting symptoms after SARS-CoV-2 infection, including myalgia, fatigue, respiratory, or neurological symptoms. Objective symptoms are often lacking, thus resembling a fibromyalgia-like syndrome. Digital therapeutics have shown efficiency in similar chronic disorders such as fibromyalgia, offering specific disease monitoring and interventions such as cognitive behavioral therapy or physical and respiratory exercise guidance.

Objective

This protocol aims to study the requirements and features of a new mobile health (mHealth) app among patients with fibromyalgia-like post–COVID-19 syndrome in a clinical trial.

Methods

We created a web application prototype for the post–COVID-19 syndrome called “POCOS,” as a web-based rehabilitation tool aiming to improve clinical outcomes. Patients without organ damage or ongoing inflammation will be included in the study. App use will be assessed through user experience questionnaires, focus groups, and clinical data analysis. Subsequently, we will analyze cross-sectional and longitudinal clinical data.

Results

The developed mHealth app consists of a clinically adapted app interface with a simplified patient-reported outcome assessment, monitoring of medical interventions, and disease activity as well as web-based instructions for specific physical and respiratory exercises, stress reduction, and lifestyle instructions. The enrollment of participants is expected to be carried out in November 2021.

Conclusions

User experience plays an important role in digital therapeutics and needs to be clinically tested to allow further improvement. We here describe this process for a new app for the treatment of the fibromyalgia-like post–COVID-19 syndrome and discuss the relevance of the potential outcomes such as natural disease course and disease phenotypes.

International Registered Report Identifier (IRRID)

PRR1-10.2196/32193

Long COVID or Post-acute Sequelae of COVID-19 (PASC): An Overview of Biological Factors That May Contribute to Persistent Symptoms

The novel virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic of coronavirus disease 2019 (COVID-19). Across the globe, a subset of patients who sustain an acute SARS-CoV-2 infection are developing a wide range of persistent symptoms that do not resolve over the course of many months. These patients are being given the diagnosis Long COVID or Post-acute sequelae of COVID-19 (PASC). It is likely that individual patients with a PASC diagnosis have different underlying biological factors driving their symptoms, none of which are mutually exclusive. This paper details mechanisms by which RNA viruses beyond just SARS-CoV-2 have be connected to long-term health consequences. It also reviews literature on acute COVID-19 and other virus-initiated chronic syndromes such as post-Ebola syndrome or myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) to discuss different scenarios for PASC symptom development. Potential contributors to PASC symptoms include consequences from acute SARS-CoV-2 injury to one or multiple organs, persistent reservoirs of SARS-CoV-2 in certain tissues, re-activation of neurotrophic pathogens such as herpesviruses under conditions of COVID-19 immune dysregulation, SARS-CoV-2 interactions with host microbiome/virome communities, clotting/coagulation issues, dysfunctional brainstem/vagus nerve signaling, ongoing activity of primed immune cells, and autoimmunity due to molecular mimicry between pathogen and host proteins. The individualized nature of PASC symptoms suggests that different therapeutic approaches may be required to best manage care for specific patients with the diagnosis.

The Enterovirus Theory of Disease Etiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Critical Review

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex, multi-system disease whose etiological basis has not been established. Enteroviruses (EVs) as a cause of ME/CFS have sometimes been proposed, as they are known agents of acute respiratory and gastrointestinal infections that may persist in secondary infection sites, including the central nervous system, muscle, and heart. To date, the body of research that has investigated enterovirus infections in relation to ME/CFS supports an increased prevalence of chronic or persistent enteroviral infections in ME/CFS patient cohorts than in healthy individuals. Nevertheless, inconsistent results have fueled a decline in related studies over the past two decades. This review covers the aspects of ME/CFS pathophysiology that are consistent with a chronic enterovirus infection and critically reviews methodologies and approaches used in past EV-related ME/CFS studies. We describe the prior sample types that were interrogated, the methods used and the limitations to the approaches that were chosen. We conclude that there is considerable evidence that prior outbreaks of ME/CFS were caused by one or more enterovirus groups. Furthermore, we find that the methods used in prior studies were inadequate to rule out the presence of chronic enteroviral infections in individuals with ME/CFS. Given the possibility that such infections could be contributing to morbidity and preventing recovery, further studies of appropriate biological samples with the latest molecular methods are urgently needed.

Review of case definitions for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

BACKGROUND

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating disease with unknown causes. From the perspectives on the etiology and pathophysiology, ME/CFS has been labeled differently, which influenced changes in case definitions and terminologies. This review sought to feature aspects of the history, developments, and differential symptoms in the case definitions.

METHODS

A search was conducted through PubMed published to February 2020 using the following search keywords: case definition AND chronic fatigue syndrome [MeSH Terms]. All reference lists of the included studies were checked. Of the included studies, the number of citations and the visibility in the literatures of the definitions were considered for comparisons of the criteria.

RESULTS

Since the first 'ME' case definition was developed in 1986, 25 case definitions/diagnostic criteria were created based on three conceptual factors (etiology, pathophysiology, and exclusionary disorders). These factors can be categorized into four categories (ME, ME/CFS, CFS, and SEID) and broadly characterized according to primary disorder (ME-viral, CFS-unknown, ME/CFS-inflammatory, SEID-multisystemic), compulsory symptoms (ME and ME/CFS-neuroinflammatory, CFS and SEID-fatigue and/or malaise), and required conditions (ME-infective agent, ME/CFS, CFS, SEID-symptoms associated with fatigue, e.g., duration of illness). ME and ME/CFS widely cover all symptom categories, while CFS mainly covers neurologic and neurocognitive symptoms. Fatigue, cognitive impairment, PEM, sleep disorder, and orthostatic intolerance were the overlapping symptoms of the 4 categories, which were included as SEID criteria.

CONCLUSIONS

This study comprehensively described the journey of the development of case definitions and compared the symptom criteria. This review provides broader insights and explanations to understand the complexity of ME/CFS for clinicians and researchers.

Post-exertional malaise is associated with greater symptom burden and psychological distress in patients diagnosed with Chronic Fatigue Syndrome

OBJECTIVE

Post-exertional malaise (PEM) is often considered a cardinal symptom of Chronic Fatigue Syndrome (CFS). There is no gold standard diagnostic method for CFS, however, and the Centers for Disease Control (CDC) Fukuda case definition does not require PEM. Research has identified differences in symptom burden between patients according to PEM, but whether it is associated with psychological distress has not been investigated.

METHODS

The CDC CFS Inventory, Fatigue Symptom Inventory, Profile of Mood States, Center for Epidemiologic Studies Depression Scale, Perceived Stress Scale, and subscales of the Sickness Impact Profile were administered to 261 patients diagnosed with the Fukuda criteria. PEM status (loPEM/hiPEM) was determined via self-reported post-exertional fatigue severity. Analyses of covariance (ANCOVA), controlling for age and gender, assessed cross-sectional group differences, and cross-sectional linear regressions using the continuous PEM severity predictor paralleled these analyses.

RESULTS

hiPEM patients reported greater symptom intensity, frequency, and interference than loPEM counterparts (p's < .001). hiPEM patients also reported greater social disruption, depressive symptoms, and mood disturbance (p's ≤ .011). Groups did not differ in recent negative life experiences, perceived stress, or demographic variables. The results of regression analyses mirrored those of ANCOVAs.

CONCLUSION

This study replicates the association between PEM and symptom burden and additionally associates PEM with psychological distress; psychological distress could, however, be a consequence of symptom burden. Differences between hiPEM and loPEM CFS patients highlight the heterogeneity of diagnoses resulting from the Fukuda criteria. It is also possible that PEM identifies particularly distressed patients for whom psychological intervention would be most beneficial.

Assessment of the scientific rigour of randomized controlled trials on the effectiveness of cognitive behavioural therapy and graded exercise therapy for patients with myalgic encephalomyelitis/chronic fatigue syndrome: A systematic review

Cognitive behavioural therapy and graded exercise therapy have been promoted as effective treatments for patients with myalgic encephalomyelitis/chronic fatigue syndrome. However, criticism on the scientific rigour of these studies has been raised. This review assessed the methodological quality of studies on the effectiveness of cognitive behavioural therapy and graded exercise therapy. The methodological quality of the 18 included studies was found to be relatively low, as bias was prominently found, affecting the main outcome measures of the studies (fatigue, physical functioning and functional impairment/status). Future research should focus on including more objective outcome measures in a well-defined patient population.

Myalgic Encephalomyelitis, Chronic Fatigue Syndrome, and Chronic Fatigue: Three Distinct Entities Requiring Complete Different Approaches

PURPOSE OF REVIEW

A recent review implicates that myalgic encephalomyelitis (ME), chronic fatigue syndrome (CFS), and chronic fatigue are part of the "fatigue spectrum" and recommends "longitudinal studies integrating biopsychosocial approaches to inform early management and targeted rehabilitation strategies."

RECENT FINDINGS

ME is a neuromuscular disease distinguished by muscle fatigability (prolonged muscle weakness after minor exertion) and specific signs of neurological dysfunction. ME is not equivalent to CFS, as proposed by the authors. CFS is defined as unexplained chronic fatigue accompanied by at least four out of a list of eight specific symptoms. CFS is a distinct clinical entity and not merely a severe variant of CF, as suggested. Proof that CF, CFS, and ME are part of a "fatigue continuum" and that CF can convert to CFS at a later stage is lacking. Biopsychosocial approaches for early management and rehabilitation of CF, as promoted by the authors, are at odds with the current understandings of ME, CFS, and CF. The (bio)psychosocial explanatory models for ME and CFS have proven to be invalid, and the associated interventions, cognitive behavioral therapy and graded exercise therapy, have shown to be ineffective and even potentially harmful. ME, CFS, and CF are three very distinct clinical entities. Interventions justified by (bio)psychosocial models appear to be unsuccessful and potentially noxious. To develop effective treatments, it is crucial to make a clear distinction between ME, CFS, and CF and to leave the (bio)psychosocial explanations and therapies behind us.

Myalgia and chronic fatigue syndrome following immunization: macrophagic myofasciitis and animal studies support linkage to aluminum adjuvant persistency and diffusion in the immune system

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a multifactorial and poorly undersood disabling disease. We present epidemiological, clinical and experimental evidence that ME/CFS constitutes a major type of adverse effect of vaccines, especially those containing poorly degradable particulate aluminum adjuvants. Evidence has emerged very slowly due to the multiplicity, lack of specificity, delayed onset, and frequent medical underestimation of ME/CFS symptoms. It was supported by an epidemiological study comparing vaccinated vs unvaccinated militaries that remained undeployed during Gulf War II. Affected patients suffer from cognitive dysfunction affecting attention, memory and inter-hemispheric connexions, well correlated to brain perfusion defects and associated with a stereotyped and distinctive pattern of cerebral glucose hypometabolism. Deltoid muscle biopsy performed to investigate myalgia typically yields macrophagic myofasciitis (MMF), a histological biomarker assessing longstanding persistency of aluminum agglomerates within innate immune cells at site of previous immunization. MMF is seemingly linked to altered mineral particle detoxification by the xeno/autophagy machinery. Comparing toxicology of different forms of aluminum and different types of exposure is misleading and inadequate and small animal experiments have turned old dogma upside down. Instead of being rapidly solubilized in the extracellular space, injected aluminum particles are quickly captured by immune cells and transported to distant organs and the brain where they elicit an inflammatory response and exert selective low dose long-term neurotoxicity. Clinical observations and experiments in sheep, a large animal like humans, confirmed both systemic diffusion and neurotoxic effects of aluminum adjuvants. Post-immunization ME/CFS represents the core manifestation of "autoimmune/inflammatory syndrome induced by adjuvants" (ASIA).

Cognitive behavioural therapy for myalgic encephalomyelitis/chronic fatigue syndrome is not effective. Re-analysis of a Cochrane review

Analysis of the 2008 Cochrane review of cognitive behavioural therapy for chronic fatigue syndrome shows that seven patients with mild chronic fatigue syndrome need to be treated for one to report a small, short-lived subjective improvement of fatigue. This is not matched by an objective improvement of physical fitness or employment and illness benefit status. Most studies in the Cochrane review failed to report on safety or adverse reactions. Patient evidence suggests adverse outcomes in 20 per cent of cases. If a trial of a drug or surgical procedure uncovered a similar high rate, it would be unlikely to be accepted as safe. It is time to downgrade cognitive behavioural therapy to an adjunct support-level therapy, rather than a treatment for chronic fatigue syndrome.

Myalgic Encephalomyelitis or What? The International Consensus Criteria

Myalgic encephalomyelitis (ME) is a neuromuscular disease with two distinctive types of symptoms (muscle fatigability or prolonged muscle weakness after minor exertion and symptoms related to neurological disturbance, especially of sensory, cognitive, and autonomic functions) and variable involvement of other bodily systems. Chronic fatigue syndrome (CFS), introduced in 1988 and re-specified in 1994, is defined as (unexplained) chronic fatigue accompanied by at least four out of eight listed (ill-defined) symptoms. Although ME and CFS are two distinct clinical entities (with partial overlap), CFS overshadowed ME for decades. In 2011, a panel of experts recommended abandoning the label CFS and its definition and proposed a new definition of ME: the International Consensus Criteria for ME (ME-ICC). In addition to post-exertional neuroimmune exhaustion (PENE), a mandatory feature, a patient must experience at least three symptoms related to neurological impairments; at least three symptoms related to immune, gastro-intestinal, and genitourinary impairments; and at least one symptom related to energy production or transportation impairments to meet the diagnosis of ME-ICC. A comparison between the original definition of ME and the ME-ICC shows that there are some crucial differences between ME and ME-ICC. Muscle fatigability, or long-lasting post-exertional muscle weakness, is the hallmark feature of ME, while this symptom is facultative for the diagnosis under the ME-ICC. PENE, an abstract notion that is very different from post-exertional muscle weakness, is the hallmark feature of the ME-ICC but is not required for the diagnosis of ME. The diagnosis of ME requires only two type of symptoms (post-exertional muscle weakness and neurological dysfunction), but a patient has to experience at least eight symptoms to meet the diagnosis according to the ME-ICC. Autonomic, sensory, and cognitive dysfunction, mandatory for the diagnosis of ME, are not compulsory to meet the ME-ICC subcriteria for 'neurological impairments'. In conclusion, the diagnostic criteria for ME and of the ME-ICC define two different patient groups. Thus, the definitions of ME and ME-ICC are not interchangeable.

Myalgic Encephalomyelitis (ME) or What? An Operational Definition

Myalgic encephalomyelitis (ME), identified as a new clinical entity with distinctive features in 1956, was originally considered as a neuromuscular disease. In 1988 the Centers for Disease Control and Prevention introduced the ill-defined concept of chronic fatigue syndrome (CFS). As predicted, CFS, unjustly considered to be a synonym for ME, pushed ME to the background. To develop effective therapies for of ME and CFS, it is essential to investigate patients with ME specifically. For that reason, an operational definition of ME is indispensable. This article proposes an operational definition based on the most recent formal definitions and symptoms observed in ME. ME is a multi-systemic illness, which (1) often has a sudden onset, in most cases a respiratory and/or gastro-intestinal infection, but a gradual or more dramatic onset is also possible; (2) has an epidemic and an endemic form; (3) has an unique clinical pattern deviating from other post-viral states; (4) is distinguished by muscle fatigability/prolonged muscle weakness after trivial exertion; (5) is accompanied by symptoms relating to neurological disturbance, especially of cognitive, autonomic, and sensory functions; (6) can be accompanied by symptoms associated with cardiac and other systems; (7) is characterized by fluctuation of symptoms (within and between "episodes"); (8) has a prolonged relapsing course; and (9) has a tendency to become chronic. In conclusion, a discriminative definition for ME contains four mandatory elements: (1) muscle fatigability/post-exertional muscle weakness lasting for days; (2) operational criteria for "neurological disturbance, especially of cognitive, autonomic and sensory functions"; (3) fluctuation of symptoms; and (4) a prolonged relapsing course. This tentative definition of ME justifies the qualification "neuromuscular disease".

Dutch Health Council Advisory Report on Myalgic Encephalomyelitis and Chronic Fatigue Syndrome: Taking the Wrong Turn

Recently, the Dutch Health Council published their advisory report on Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS) which is meant to determine the medical policy with regard to ME in the Netherlands. The Health Council briefly discusses several diagnostic criteria and proposes to use new diagnostic criteria for "ME/CFS" in research and clinical practice in the future. The advisory report then summarizes organic abnormalities observed in the last decades and concludes that "ME/CFS" is a "serious, chronic, multisystem disease". According to the Health Council there are no curative treatments for "ME/CFS", due to lack of knowledge, but specific medication could bring symptomatic relief. The Health Council recommends conducting more research, to (re)educate medical professionals about "ME/CFS", to appoint three academic expertise centres, which will install a care network for patients, and to fairly judge the limitations (disability) of patients when they apply for a disability income, medical aid and care. The advisory report was welcomed by many patients, because it puts an end to the dominance of the (bio)psychosocial explanatory model and seems to offer a perspective of improving the situation of patients. However, the starting point of the advisory report, a new definition of "ME/CFS", will have serious (long-lasting) consequences for patients and researchers.

Integration of DNA methylation & health scores identifies subtypes in myalgic encephalomyelitis/chronic fatigue syndrome

AIM

To identify subtypes in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) based on DNA methylation profiles and health scores.

METHODS

DNA methylome profiles in immune cells were integrated with symptomatology from 70 women with ME/CFS using similarity network fusion to identify subtypes.

RESULTS

We discovered four ME/CFS subtypes associated with DNA methylation modifications in 1939 CpG sites, three RAND-36 categories and five DePaul Symptom Questionnaire measures. Methylation patterns of immune response genes and differences in physical functioning and postexertional malaise differentiated the subtypes.

CONCLUSION

ME/CFS subtypes are associated with specific DNA methylation differences and health symptomatology and provide additional evidence of the potential relevance of metabolic and immune differences in ME/CFS with respect to specific symptoms.

A reexamination of the cognitive behavioral model of chronic fatigue syndrome

OBJECTIVE

The cognitive behavioral model of chronic fatigue syndrome (CFS) suggests that cognitions and reduced activity level perpetuate the fatigue and impairment that individuals with CFS experience. The two empirical evaluations of this model resulted in conflicting findings. The current study examines the influence of case definition fulfillment on the applicability of this model to CFS.

METHOD

A moderated mediation analysis was conducted on 990 individuals with CFS to reexamine the behavioral pathway of this model. Case definition fulfillment was entered as a moderator.

RESULTS

Findings were generally inconsistent with the cognitive behavioral model of CFS. Case definition fulfillment significantly moderated the relation between activity level and physical impairment (β = -0.08, p = 0.03); individuals who met more stringent case definitions demonstrated a weaker relation between activity level and impairment.

CONCLUSIONS

This model may not accurately represent the experience of individuals with CFS, particularly those who fulfill more stringent case definitions.

Chronic fatigue syndrome in childhood: seven-year follow-up study

This study explores the outcome and longer-term sequelae of suffering chronic fatigue syndrome in childhood. Ten such children, ranging from 10 to 16 years of age at diagnosis, were followed up into adulthood, an average of seven years. Most were completely well or markedly improved (seven of nine). Only children fully engaged in therapy made a total recovery. However, respondents felt medical staff did not believe their symptoms and that rehabilitative strategies were unhelpful. No physical or mental illness was subsequently diagnosed to account for the original symptom presentation. Childhood sufferers maintained the same pattern of symptoms as adults. Depressive symptomatology was present in two cases. The overall longer-term prognosis for children suffering chronic fatigue syndrome is good. A successful doctor-patient relationship is essential to improve compliance with management plans.

A Comparison of Case Definitions for Myalgic Encephalomyelitis and Chronic Fatigue Syndrome

Many professionals have described the clinical presentation of myalgic encephalomyelitis (ME), but recent efforts have focused on the development of ME criteria that can be reliably applied. The current study compared the symptoms and functioning of individuals who met the newly-developed Institute of Medicine (IOM) clinical criteria to a revised version of the London criteria for ME. While 76% of a sample diagnosed with chronic fatigue syndrome (CFS) met the IOM criteria, 44% met the revised London criteria. The revised London criteria identified patients with greater physical impairment. The results of this study indicate the need for a standard case definition with specific guidelines for operationalization. The application of case definitions has important implications for the number of individuals identified with ME, the pattern of symptoms experienced by these individuals, and the severity of their symptoms and functional limitations. Sample heterogeneity across research studies hinders researchers from replicating findings and impedes the search for biological markers and effective treatments.

Myalgic encephalomyelitis, chronic fatigue syndrome: An infectious disease

The etiology of myalgic encephalomyelitis also known as chronic fatigue syndrome or ME/CFS has not been established. Controversies exist over whether it is an organic disease or a psychological disorder and even the existence of ME/CFS as a disease entity is sometimes denied. Suggested causal hypotheses have included psychosomatic disorders, infectious agents, immune dysfunctions, autoimmunity, metabolic disturbances, toxins and inherited genetic factors. Clinical, immunological and epidemiological evidence supports the hypothesis that: ME/CFS is an infectious disease; the causal pathogen persists in patients; the pathogen can be transmitted by casual contact; host factors determine susceptibility to the illness; and there is a population of healthy carriers, who may be able to shed the pathogen. ME/CFS is endemic globally as sporadic cases and occasional cluster outbreaks (epidemics). Cluster outbreaks imply an infectious agent. An abrupt flu-like onset resembling an infectious illness occurs in outbreak patients and many sporadic patients. Immune responses in sporadic patients resemble immune responses in other infectious diseases. Contagion is shown by finding secondary cases in outbreaks, and suggested by a higher prevalence of ME/CFS in sporadic patients' genetically unrelated close contacts (spouses/partners) than the community. Abortive cases, sub-clinical cases, and carrier state individuals were found in outbreaks. The chronic phase of ME/CFS does not appear to be particularly infective. Some healthy patient-contacts show immune responses similar to patients' immune responses, suggesting exposure to the same antigen (a pathogen). The chronicity of symptoms and of immune system changes and the occurrence of secondary cases suggest persistence of a causal pathogen. Risk factors which predispose to developing ME/CFS are: a close family member with ME/CFS; inherited genetic factors; female gender; age; rest/activity; previous exposure to stress or toxins; various infectious diseases preceding the onset of ME/CFS; and occupational exposure of health care professionals. The hypothesis implies that ME/CFS patients should not donate blood or tissue and usual precautions should be taken when handling patients' blood and tissue. No known pathogen has been shown to cause ME/CFS. Confirmation of the hypothesis requires identification of a causal pathogen. Research should focus on a search for unknown and known pathogens. Finding a causal pathogen could assist with diagnosis; help find a biomarker; enable the development of anti-microbial treatments; suggest preventive measures; explain pathophysiological findings; and reassure patients about the validity of their symptoms.

Neurasthenia and Chronic Fatigue: Theory and Practice in Britain and America

The symptoms that make up the construct of neuras thenia, including fatigue and exhaustion, are dimension ally distributed in the community. The decision to create a category called neurasthenia is an arbitrary one, influenced by issues of severity and morbidity. The prevalence and nature of the resulting concept are also substantially influenced by the decision on how to classify the close relationships among excessive fatigue, depression and anxiety. Superimposed upon this classi fication is a second, parallel structure of illness beliefs. The original construct of neurasthenia as a physical disease that resulted from overwork, was of consider able utility to both doctors and patients. This early concept of neurasthenia can be recognized in the modem revival of interest in chronic fatigue syndrome (CFS) in Western cultures. The current highly charged atmosphere surrounding these diagnoses reflects the issues of legitimacy and non-legitimacy in illness, usually expressed in competing physical and psychologi cal explanations of ill health.

Fatigue and Activity Patterns of People with Chronic Fatigue Syndrome

Although fatigue is the central symptom of people with chronic fatigue syndrome (CFS), relatively few reports in the literature examine the severity of this fatigue or the activity patterns of people with CFS. Using the Fatigue Severity Scale, the Nottingham Health Profile, the Human Activity Profile, and the Activity Record, severity of fatigue, health status, and activity patterns were investigated. People with CFS reported significantly higher levels of fatigue, poorer health status, and engagement in less energy-demanding activities ( P<0.001) than people without CFS. Those with CFS spent 16.18% (standard deviation [SD]=9.62) of their time resting compared with only 2.28% (SD=3.26) of the time spent by those without CFS ( P<0.05). Time spent in productive activities (household activities and work) was also significantly different, with the CFS group less involved ( P<0.05). This severity of fatigue and limitations in activity patterns warrant further attention. Frequent rest periods and energy conservation training may benefit these clients.

Is chronic fatigue syndrome treatable in an NHS environment?

The combined approach of graded activity and cognitive behaviour therapy in the treatment and management of chronic fatigue syndrome within an inpatient NHS neurology ward is discussed. A retrospective medical audit of 28 patients indicated that 57% had an increased activity level six months following discharge. Controlled clinical studies are required to examine the benefit and effect of the combined treatment approach discussed.

Case definitions integrating empiric and consensus perspectives

BACKGROUND

There has been considerable controversy regarding how to name and define the illnesses known as myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS). The IOM report has proposed a new clinical criteria and name for this illness, but aspects of these recommendations have been scrutinized by patients and scientists.

PURPOSE

It is possible that both empiric and consensus approaches could be used to help settle some of these diagnostic challenges. Using patient samples collected in the United States, Great Britain, and Norway (N=556), the current study attempted to categorize patients using more general as well as more restricted case definitions.

RESULTS

Overall, the outcomes suggest that there might be four groupings of patients, with the broadest category involving those with chronic fatigue (N=62), defined by 6 or more months of fatigue which can be cannot be explained by medical or psychiatric conditions. A second category involves those patients that have chronic fatigue that can be explained by a medical or psychiatric condition (N=47). A third category involves more specific criteria that have been posited both by the IOM report, a Canadian Clinical Case criteria, a ME-ICC criteria and a more empiric approach. These efforts have specified domains of substantial reductions of activity, post-exertional malaise, neurocognitive impairment, and sleep dysfunction (N=346). Patients with these characteristics were more functionally impaired than those meeting just chronic fatigue criteria, p < .05. Finally, those meeting even more restrictive ME criteria proposed by Ramsay, identified a smaller and even more impaired group, p < .05.

DISCUSSION

The advantages of using such empirical and consensus approaches to develop reliable classification and diagnostic efforts are discussed.

Educational strategies for chronically ill students: Chronic Fatigue Syndrome

Chronic illness, such as Chronic Fatigue Syndrome, has a major impact on the sociol, emotional, and educational well-being of the young people affected by it. Many students are either absent from school for prolonged periods or able to attend for only a few classes each week. Students have identified the importance of educational strategies in the management of their illness. If the school or educational setting is functioning appropriately, then social, emotional, developmental, and academic issues associated with chronic illness gradually resolve. A program developed in conjunction with the Victorian Visiting Teacher Service is described. Strategies used to assist housebound students, their carers, teaching staff, and students who are gradually returning to school are outlined.

Accurate diagnosis of myalgic encephalomyelitis and chronic fatigue syndrome based upon objective test methods for characteristic symptoms

Although myalgic encephalomyelitis (ME) and chronic fatigue syndrome (CFS) are considered to be synonymous, the definitional criteria for ME and CFS define two distinct, partially overlapping, clinical entities. ME, whether defined by the original criteria or by the recently proposed criteria, is not equivalent to CFS, let alone a severe variant of incapacitating chronic fatigue. Distinctive features of ME are: muscle weakness and easy muscle fatigability, cognitive impairment, circulatory deficits, a marked variability of the symptoms in presence and severity, but above all, post-exertional “malaise”: a (delayed) prolonged aggravation of symptoms after a minor exertion. In contrast, CFS is primarily defined by (unexplained) chronic fatigue, which should be accompanied by four out of a list of 8 symptoms, e.g., headaches. Due to the subjective nature of several symptoms of ME and CFS, researchers and clinicians have questioned the physiological origin of these symptoms and qualified ME and CFS as functional somatic syndromes. However, various characteristic symptoms, e.g., post-exertional “malaise” and muscle weakness, can be assessed objectively using well-accepted methods, e.g., cardiopulmonary exercise tests and cognitive tests. The objective measures acquired by these methods should be used to accurately diagnose patients, to evaluate the severity and impact of the illness objectively and to assess the positive and negative effects of proposed therapies impartially.

Defining Essential Features of Myalgic Encephalomyelitis and Chronic Fatigue Syndrome

Considerable debate surrounds the search for the defining features of patients with Myalgic Encephalomyelitis (ME) and chronic fatigue syndrome (CFS). Current case definitions were created through clinical consensus. Failure to operationalize these case definitions has led to considerable variability in the identification of patients. In addition, some case definitions (e.g., Fukuda et al., 1994) do not require cardinal symptoms of this illness, where as other case definitions do require core symptoms of this illness (Carruthers et al., 2003, 2011), and these latter case criteria appear to identify a more impaired group of patients. Criterion variance is most likely to occur when operationally explicit criteria do not exist for diagnostic categories (Spitzer, Endicott, & Robins, 1978), or when there are varying criteria for contrasting case definitions, which is an impediment to the research in this field. To deal with this problem, it is possible to differentiate those that meet more loosely defined criteria from those that are more narrowly and defined, thus differentiating CFS from ME. In order to progress the search for biological markers and effective treatments, essential features need to be operationalized and broadly used in order to increase the probability that individuals included in samples have the same underlying illness.

Chronic fatigue syndrome versus sudden onset myalgic encephalomyelitis

A revised sudden onset case definition for Myalgic Encephalomyelitis (ME) has been developed (Jason, Damrongvachiraphan, et al., 2012 ) based on past case definitions. In a prior study, Jason, Brown, and colleagues ( 2012 ) compared patients recruited using the 1994 case definition of chronic fatigue syndrome (CFS) to contrast those meeting criteria for the revised ME criteria. They found that this revised ME case definition identified patients with more functional impairments and physical, mental, and cognitive problems than those meeting the CFS criteria. The study by Jason, Brown, et al. ( 2012 ) only selected individuals who first met the CFS criteria, and it only relied on one Chicago-based data set. The current study replicated this comparison with two distinct data sets with different case ascertainment methods. Results indicate that the ME criteria identified a group of patients with more functional disabilities as well as more severe post-exertional malaise symptoms.

Myalgic Encephalomyelitis: Symptoms and Biomarkers

Myalgic Encephalomyelitis (ME) continues to cause significant morbidity worldwide with an estimated one million cases in the United States. Hurdles to establishing consensus to achieve accurate evaluation of patients with ME continue, fueled by poor agreement about case definitions, slow progress in development of standardized diagnostic approaches, and issues surrounding research priorities. Because there are other medical problems, such as early MS and Parkinson's Disease, which have some similar clinical presentations, it is critical to accurately diagnose ME to make a differential diagnosis. In this article, we explore and summarize advances in the physiological and neurological approaches to understanding, diagnosing, and treating ME. We identify key areas and approaches to elucidate the core and secondary symptom clusters in ME so as to provide some practical suggestions in evaluation of ME for clinicians and researchers. This review, therefore, represents a synthesis of key discussions in the literature, and has important implications for a better understanding of ME, its biological markers, and diagnostic criteria. There is a clear need for more longitudinal studies in this area with larger data sets, which correct for multiple testing.

A critical analysis of the proposal of the Institute of Medicine to replace myalgic encephalomyelitis and chronic fatigue syndrome by a new diagnostic entity called systemic exertion intolerance disease

The Institute of Medicine (IOM) recently published their report in response to an assignment "to define diagnostic criteria for Myalgic Encephalomyelitis (ME)/chronic fatigue syndrome (CFS), to propose a process for reevaluation of these criteria in the future, and to consider whether a new name for this disease is warranted". The basic pre-assumption of the IOM committee for the development of evidence-based diagnostic criteria for ME/CFS was that ME and CFS denote conditions with similar symptoms, hence ME/CFS. The IOM committee recommends: (1) that ME/CFS will be renamed 'systemic exertion intolerance disease' (SEID); and that a new code should be assigned to SEID in the International Classification of Diseases (ICD), replacing the existing codes for ME (a neurological disease: G93.3) and CFS ('signs, symptoms, and abnormal clinical and laboratory findings, not elsewhere classified': R53.82); (2) that a diagnosis of SEID should be made if the new diagnostic criteria are met; (3) that the Department of Health and Human Services develops a toolkit appropriate for screening and diagnosing patients; and (4) that a multidisciplinary group re-examines the new diagnostic criteria when necessary. This editorial reviews the working procedure of the IOM and two of the outcomes: the recommendation to introduce a new clinical entity (SEID) and new diagnostic criteria. Based upon the contents of the report, and the arguments of the IOM, a search of PubMed and the archive of the Journal of Chronic Fatigue Syndrome using the search terms ME (and old synonyms) and CFS, and a search of PubMed related to the five core symptoms of SEID was conducted. Reviewing the working method and the recommendations, it is concluded that the new diagnostic criteria for SEID are based upon important methodological shortcomings and that the introduction of SEID to replace both ME and CFS has several profound negative consequences outweighing the advantages.

What is in a name? Comparing diagnostic criteria for chronic fatigue syndrome with or without fibromyalgia

The current study had two objectives. (1) to compare objective and self-report measures in patients with chronic fatigue syndrome (CFS) according to the 1994 Center for Disease Control (CDC) criteria, patients with multiple sclerosis (MS), and healthy controls, and (2) to contrast CFS patients who only fulfill CDC criteria to those who also fulfill the criteria for myalgic encephalomyelitis (ME), the 2003 Canadian criteria for ME/CFS, or the comorbid diagnosis of fibromyalgia (FM). One hundred six participants (48 CFS patients diagnosed following the 1994 CDC criteria, 19 MS patients, and 39 healthy controls) completed questionnaires assessing symptom severity, quality of life, daily functioning, and psychological factors. Objective measures consisted of activity monitoring, evaluation of maximal voluntary contraction and muscle recovery, and cognitive performance. CFS patients were screened whether they also fulfilled ME criteria, the Canadian criteria, and the diagnosis of FM. CFS patients scored higher on symptom severity, lower on quality of life, and higher on depression and kinesiophobia and worse on MVC, muscle recovery, and cognitive performance compared to the MS patients and the healthy subjects. Daily activity levels were also lower compared to healthy subjects. Only one difference was found between those fulfilling the ME criteria and those who did not regarding the degree of kinesiophobia (lower in ME), while comorbidity for FM significantly increased the symptom burden. CFS patients report more severe symptoms and are more disabled compared to MS patients and healthy controls. Based on the present study, fulfillment of the ME or Canadian criteria did not seem to give a clinically different picture, whereas a diagnosis of comorbid FM selected symptomatically worse and more disabled patients.

Validating a measure of myalgic encephalomyelitis/chronic fatigue syndrome symptomatology

OBJECTIVES

The present study sought to validate a comprehensive self-report measure of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) symptomatology to aid in clinical and research assessment.

METHOD

Exploratory factor analysis (EFA) was used to establish the underlying factor structure of the DePaul Symptom Questionnaire (DSQ) (Jason, Evans, et al., 2010) using a well-characterized sample of individuals (92.6% met the Fukuda et al. criteria (1994) and/or the Clinical Canadian Criteria (Carruthers et al., 2003)), and this structure was then tested on a less stringently recruited sample of individuals utilizing a confirmatory factor analysis (CFA). Convergent and discriminant validity of the DSQ were also examined utilizing alternative measures of symptomatology and functioning.

RESULTS

A 3-factor solution was found using EFA (Neuroendocrine, Autonomic & Immune Dysfunction; Neurological/Cognitive Dysfunction; Post-Exertional Malaise) and the fit of this factor structure was adequate for the second sample.

DISCUSSION

The DSQ is a valid measure of ME/CFS symptomatology. The emergent factors were consistent with previous literature on symptom clusters, and convergent and discriminant validity were established.

The status of and future research into Myalgic Encephalomyelitis and Chronic Fatigue Syndrome: the need of accurate diagnosis, objective assessment, and acknowledging biological and clinical subgroups

Although Myalgic Encephalomyelitis (ME) and Chronic Fatigue Syndrome (CFS) are used interchangeably, the diagnostic criteria define two distinct clinical entities. Cognitive impairment, (muscle) weakness, circulatory disturbances, marked variability of symptoms, and, above all, post-exertional malaise: a long-lasting increase of symptoms after a minor exertion, are distinctive symptoms of ME. This latter phenomenon separates ME, a neuro-immune illness, from chronic fatigue (syndrome), other disorders and deconditioning. The introduction of the label, but more importantly the diagnostic criteria for CFS have generated much confusion, mostly because chronic fatigue is a subjective and ambiguous notion. CFS was redefined in 1994 into unexplained (persistent or relapsing) chronic fatigue, accompanied by at least four out of eight symptoms, e.g., headaches and unrefreshing sleep. Most of the research into ME and/or CFS in the last decades was based upon the multivalent CFS criteria, which define a heterogeneous patient group. Due to the fact that fatigue and other symptoms are non-discriminative, subjective experiences, research has been hampered. Various authors have questioned the physiological nature of the symptoms and qualified ME/CFS as somatization. However, various typical symptoms can be assessed objectively using standardized methods. Despite subjective and unclear criteria and measures, research has observed specific abnormalities in ME/CFS repetitively, e.g., immunological abnormalities, oxidative and nitrosative stress, neurological anomalies, circulatory deficits and mitochondrial dysfunction. However, to improve future research standards and patient care, it is crucial that patients with post-exertional malaise (ME) and patients without this odd phenomenon are acknowledged as separate clinical entities that the diagnosis of ME and CFS in research and clinical practice is based upon accurate criteria and an objective assessment of characteristic symptoms, as much as possible that well-defined clinical and biological subgroups of ME and CFS patients are investigated in more detail, and that patients are monitored before, during and after interventions with objective measures and biomarkers.

Case definitions for chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME): a systematic review

OBJECTIVE

To identify case definitions for chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME), and explore how the validity of case definitions can be evaluated in the absence of a reference standard.

DESIGN

Systematic review.

SETTING

International.

PARTICIPANTS

A literature search, updated as of November 2013, led to the identification of 20 case definitions and inclusion of 38 validation studies.

PRIMARY AND SECONDARY OUTCOME MEASURE

Validation studies were assessed for risk of bias and categorised according to three validation models: (1) independent application of several case definitions on the same population, (2) sequential application of different case definitions on patients diagnosed with CFS/ME with one set of diagnostic criteria or (3) comparison of prevalence estimates from different case definitions applied on different populations.

RESULTS

A total of 38 studies contributed data of sufficient quality and consistency for evaluation of validity, with CDC-1994/Fukuda as the most frequently applied case definition. No study rigorously assessed the reproducibility or feasibility of case definitions. Validation studies were small with methodological weaknesses and inconsistent results. No empirical data indicated that any case definition specifically identified patients with a neuroimmunological condition.

CONCLUSIONS

Classification of patients according to severity and symptom patterns, aiming to predict prognosis or effectiveness of therapy, seems useful. Development of further case definitions of CFS/ME should be given a low priority. Consistency in research can be achieved by applying diagnostic criteria that have been subjected to systematic evaluation.

Contrasting case definitions for chronic fatigue syndrome, Myalgic Encephalomyelitis/chronic fatigue syndrome and myalgic encephalomyelitis

This article uses data from patients recruited using the 1994 case definition of chronic fatigue syndrome (CFS) to contrast those meeting criteria for the Myalgic Encephalomyelitis/chronic fatigue syndrome (ME/CFS) Canadian case definition with those that did not meet these criteria. The study also contrasts those meeting criteria for Myalgic Encephalomyelitis (ME) based on criteria from Ramsay and other theorists with those that did not meet the ME criteria. The ME/CFS case definition criteria identified a subset of patients with more functional impairments and physical, mental, and cognitive problems than the subset not meeting these criteria. The ME subset had more functional impairments, and more severe physical and cognitive symptoms than the subset not meeting ME criteria. When applied to a population meeting the 1994 CFS case definition, both ME/CFS and ME criteria appear to select a more severe subset of patients.

Myalgic encephalomyelitis: International Consensus Criteria

The label 'chronic fatigue syndrome' (CFS) has persisted for many years because of the lack of knowledge of the aetiological agents and the disease process. In view of more recent research and clinical experience that strongly point to widespread inflammation and multisystemic neuropathology, it is more appropriate and correct to use the term 'myalgic encephalomyelitis' (ME) because it indicates an underlying pathophysiology. It is also consistent with the neurological classification of ME in the World Health Organization's International Classification of Diseases (ICD G93.3). Consequently, an International Consensus Panel consisting of clinicians, researchers, teaching faculty and an independent patient advocate was formed with the purpose of developing criteria based on current knowledge. Thirteen countries and a wide range of specialties were represented. Collectively, members have approximately 400 years of both clinical and teaching experience, authored hundreds of peer-reviewed publications, diagnosed or treated approximately 50 000 patients with ME, and several members coauthored previous criteria. The expertise and experience of the panel members as well as PubMed and other medical sources were utilized in a progression of suggestions/drafts/reviews/revisions. The authors, free of any sponsoring organization, achieved 100% consensus through a Delphi-type process. The scope of this paper is limited to criteria of ME and their application. Accordingly, the criteria reflect the complex symptomatology. Operational notes enhance clarity and specificity by providing guidance in the expression and interpretation of symptoms. Clinical and research application guidelines promote optimal recognition of ME by primary physicians and other healthcare providers, improve the consistency of diagnoses in adult and paediatric patients internationally and facilitate clearer identification of patients for research studies.

Prevalence of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) in three regions of England: a repeated cross-sectional study in primary care

BACKGROUND

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) or chronic fatigue syndrome (CFS) has been used to name a range of chronic conditions characterized by extreme fatigue and other disabling symptoms. Attempts to estimate the burden of disease have been limited by selection bias, and by lack of diagnostic biomarkers and of agreed reproducible case definitions. We estimated the prevalence and incidence of ME/CFS in three regions in England, and discussed the implications of frequency statistics and the use of different case definitions for health and social care planning and for research.

METHODS

We compared the clinical presentation, prevalence and incidence of ME/CFS based on a sample of 143,000 individuals aged 18 to 64 years, covered by primary care services in three regions of England. Case ascertainment involved: 1) electronic search for chronic fatigue cases; 2) direct questioning of general practitioners (GPs) on cases not previously identified by the search; and 3) clinical review of identified cases according to CDC-1994, Canadian and Epidemiological Case (ECD) Definitions. This enabled the identification of cases with high validity.

RESULTS

The estimated minimum prevalence rate of ME/CFS was 0.2% for cases meeting any of the study case definitions, 0.19% for the CDC-1994 definition, 0.11% for the Canadian definition and 0.03% for the ECD. The overall estimated minimal yearly incidence was 0.015%. The highest rates were found in London and the lowest in East Yorkshire. All but one of the cases conforming to the Canadian criteria also met the CDC-1994 criteria, however presented higher prevalence and severity of symptoms.

CONCLUSIONS

ME/CFS is not uncommon in England and represents a significant burden to patients and society. The number of people with chronic fatigue who do not meet specific criteria for ME/CFS is higher still. Both groups have high levels of need for service provision, including health and social care. We suggest combining the use of both the CDC-1994 and Canadian criteria for ascertainment of ME/CFS cases, alongside careful clinical phenotyping of study participants. This combination if used systematically will enable international comparisons, minimization of bias, and the identification and investigation of distinct sub-groups of patients with possibly distinct aetiologies and pathophysiologies, standing a better chance of translation into effective specific treatments.

Fatigue in adult patients with primary immune thrombocytopenia

BACKGROUND

 Patients with primary immune thrombocytopenia (ITP) commonly describe symptoms of fatigue. However, hematologists rarely consider fatigue a manifestation of ITP.

OBJECTIVES

  To document the prevalence of fatigue among patients with ITP and to determine the patient characteristics that are associated with fatigue.   Using a cross-sectional design, we surveyed 1871 members of the UK ITP Support Association [585 (31%) responded], and 93 patients enrolled in the Oklahoma (US) ITP Registry [68 (73%) responded] with questions about their ITP and with validated symptom assessment scales for fatigue, daytime sleepiness, and orthostatic symptoms.

RESULTS

  The prevalence of fatigue among both UK (39%) and US (22%) patients was significantly greater than expected compared with normal subjects (P<0.0001 and P<0.0001 respectively). In univariate analysis of the combined cohorts, fatigue was associated with a platelet count <100000/μL, treatment with steroids, bleeding symptoms, presence of other medical conditions, daytime sleepiness, and orthostatic symptoms. Fatigue was not associated with age, gender, duration of ITP, or splenectomy status. Multivariate analysis of the combined cohorts was stratified for the presence or absence of bleeding symptoms. Among 107 patients with bleeding symptoms, fatigue was independently associated with a platelet count <100000/μL and female gender. Among 491 patients without bleeding symptoms, fatigue was independently associated with a platelet count <30000/μL, presence of other medical conditions, daytime sleepiness, and orthostatic symptoms.

CONCLUSIONS

  Fatigue is a common symptom among patients with ITP. These data provide the basis for future studies to define the clinical importance of fatigue in ITP.

EBV Chronic Infections

The infection from Epstein-Barr virus (EBV) or virus of infectious mononucleosis, together with other herpes viruses' infections, represents a prototype of persistent viral infections characterized by the property of the latency. Although the reactivations of the latent infection are associated with the resumption of the viral replication and eventually with the "shedding", it is still not clear if this virus can determine chronic infectious diseases, more or less evolutive. These diseases could include some pathological conditions actually defined as "idiopathic"and characterized by the "viral persistence" as the more credible pathogenetic factor. Among the so-called idiopathic syndromes, the "chronic fatigue syndrome" (CFS) aroused a great interest around the eighties of the last century when, just for its relationship with EBV, it was called "chronic mononucleosis" or "chronic EBV infection".Today CFS, as defined in 1994 by the CDC of Atlanta (USA), really represents a multifactorial syndrome characterized by a chronic course, where reactivation and remission phases alternate, and by a good prognosis. The etiopathogenetic role of EBV is demonstrated only in a well-examined subgroup of patients, while in most of the remaining cases this role should be played by other infectious agents - able to remain in a latent or persistent way in the host - or even by not infectious agents (toxic, neuroendocrine, methabolic, etc.). However, the pathogenetic substrate of the different etiologic forms seems to be the same, much probably represented by the oxidative damage due to the release of pro-inflammatory cytokines as a response to the triggering event (infectious or not infectious).Anyway, recently the scientists turned their's attention to the genetic predisposition of the subjects affected by the syndrome, so that in the last years the genetic studies, together with those of molecular biology, received a great impulse. Thanks to both these studies it was possibile to confirm the etiologic links between the syndrome and EBV or other herpesviruses or other persistent infectious agents.The mechanisms of EBV latency have been carefully examined both because they represent the virus strategy to elude the response of the immune system of the host, and because they are correlated with those oncologic conditions associated to the viral persistence, particularly lymphomas and lymphoproliferative disorders. Just these malignancies, for which a pathogenetic role of EBV is clearly documented, should represent the main clinical expression of a first group of chronic EBV infections characterized by a natural history where the neoplastic event aroused from the viral persistence in the resting B cells for all the life, from the genetic predisposition of the host and from the oncogenic potentialities of the virus that chronically persists and incurs reactivations.Really, these oncological diseases should be considered more complications than chronic forms of the illness, as well as other malignancies for which a viral - or even infectious - etiology is well recognized. The chronic diseases, in fact, should be linked in a pathogenetic and temporal way to the acute infection, from whom start the natural history of the following disease. So, as for the chronic liver diseases from HBV and HCV, it was conied the acronym of CAEBV (Chronic Active EBV infection), distinguishing within these pathologies the more severe forms (SCAEBV) mostly reported in Far East and among children or adolescents. Probably only these forms have to be considered expressions of a chronic EBV infection "sensu scrictu", together with those forms of CFS where the etiopathogenetic and temporal link with the acute EBV infection is well documented. As for CFS, also for CAEBV the criteria for a case definition were defined, even on the basis of serological and virological findings. However, the lymphoproliferative disorders are excluded from these forms and mantain their nosographic (e.g. T or B cell or NK type lymphomas) and pathogenetic collocation, even when they occur within chronic forms of EBV infection. In the pathogenesis, near to the programs of latency of the virus, the genetic and environmental factors, independent from the real natural history of EBV infection, play a crucial role.Finally, it was realized a review of cases - not much numerous in literature - of chronic EBV infection associated to chronic liver and neurological diseases, where the modern techniques of molecular biology should be useful to obtain a more exact etiologic definition, not always possibile to reach in the past.The wide variety of clinical forms associated to the EBV chronic infection makes difficult the finding of a univocal pathogenetic link. There is no doubt, however, that a careful examination of the different clinical forms described in this review should be useful to open new horizons to the study of the persistent viral infections and the still not well cleared pathologies that they can induce in the human host.

Chronic fatigue syndrome and mitochondrial dysfunction

This study aims to improve the health of patients suffering from chronic fatigue syndrome (CFS) by interventions based on the biochemistry of the illness, specifically the function of mitochondria in producing ATP (adenosine triphosphate), the energy currency for all body functions, and recycling ADP (adenosine diphosphate) to replenish the ATP supply as needed. Patients attending a private medical practice specializing in CFS were diagnosed using the Centers for Disease Control criteria. In consultation with each patient, an integer on the Bell Ability Scale was assigned, and a blood sample was taken for the "ATP profile" test, designed for CFS and other fatigue conditions. Each test produced 5 numerical factors which describe the availability of ATP in neutrophils, the fraction complexed with magnesium, the efficiency of oxidative phosphorylation, and the transfer efficiencies of ADP into the mitochondria and ATP into the cytosol where the energy is used. With the consent of each of 71 patients and 53 normal, healthy controls the 5 factors have been collated and compared with the Bell Ability Scale. The individual numerical factors show that patients have different combinations of biochemical lesions. When the factors are combined, a remarkable correlation is observed between the degree of mitochondrial dysfunction and the severity of illness (P<0.001). Only 1 of the 71 patients overlaps the normal region. The "ATP profile" test is a powerful diagnostic tool and can differentiate patients who have fatigue and other symptoms as a result of energy wastage by stress and psychological factors from those who have insufficient energy due to cellular respiration dysfunction. The individual factors indicate which remedial actions, in the form of dietary supplements, drugs and detoxification, are most likely to be of benefit, and what further tests should be carried out.

Inflammatory and oxidative and nitrosative stress pathways underpinning chronic fatigue, somatization and psychosomatic symptoms

PURPOSE OF REVIEW

The aim of this paper is to review recent findings on inflammatory and oxidative and nitrosative stress (IO&NS) pathways in chronic fatigue and somatization disorder.

RECENT FINDINGS

Activation of IO&NS pathways is the key phenomenon underpinning chronic fatigue syndrome (CFS): intracellular inflammation, with an increased production of nuclear factor kappa beta (NFkappabeta), cyclo-oxygenase-2 (COX-2) and inducible NO synthase (iNOS); and damage caused by O&NS to membrane fatty acids and functional proteins. These IO&NS pathways are induced by a number of trigger factors, for example psychological stress, strenuous exercise, viral infections and an increased translocation of LPS from gram-bacteria (leaky gut). The 'psychosomatic' symptoms experienced by CFS patients are caused by intracellular inflammation (aches and pain, muscular tension, fatigue, irritability, sadness, and the subjective feeling of infection); damage caused by O&NS (aches and pain, muscular tension and fatigue); and gut-derived inflammation (complaints of irritable bowel). Inflammatory pathways (monocytic activation) are also detected in somatizing disorder.

SUMMARY

'Functional' symptoms, as occurring in CFS and somatization, have a genuine organic cause, that is activation of peripheral and central IO&NS pathways and gut-derived inflammation. The development of new drugs, aimed at treating those disorders, should target these IO&NS pathways.