Category: Overview

Overview of chronic fatigue syndrome focusing on prevalence and diagnostic criteria

Abstract:

Chronic fatigue syndrome (CFS) is an operational concept proposed by Centers for Disease Control and Prevention to clarify the unknown etiology of the syndrome characterized by the sensation of abnormally prolonged fatigue. Lots of investigators reported various abnormalities such as virus infection, immune abnormalities, HPA axis abnormalities, metabolic abnormalities, etc., but there are a few abnormalities common to vast majority cases of CFS. Therefore, lots of people as well as medical doctors are still skeptical about the presence of CFS.

However, recent studies reveal that CFS can be understood to be a special condition based on the abnormality of neuroendocrine-immunologic system caused by the psycho-social stress and some genetic components. Under these conditions, a reactivation of various kinds of herpes virus infections and/or chronic infections might occur as a result of immune dysfunction, causing the abnormal production of several cytokines. A distinctive feature of CFS is thought to be the secondary brain dysfunction caused by the abnormal production of several cytokines. In this paper, I show the overview of CFS focusing around prevalence, economic impact and diagnostic criteria in Japan.

 

Source: Kuratsune H. Overview of chronic fatigue syndrome focusing on prevalence and diagnostic criteria. Nihon Rinsho. 2007 Jun;65(6):983-90. [Article in Japanese] https://www.ncbi.nlm.nih.gov/pubmed/17561686

 

Chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is thought to have a worldwide prevalence of 0.4-1% with approximately 240,000 patients in the UK. Diagnosis is based on clinical criteria and critically depends on exclusion of other physical and psychiatric diseases. Studies of pathogenesis have revealed immune system abnormalities and chronic immune activation, dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis, brain abnormalities, evidence of emotional stress (comprising host aspects) and evidence of exogenous insults, for example, various microbial infections (Epstein-Barr virus, enteroviruses, parvovirus B19, Coxiella burnetii and Chlamydia pneumoniae), vaccinations and exposure to organophosphate chemicals and other toxins (comprising environmental aspects).

Emotional stress appears to be very important as it reduces the ability of the immune system to clear infections, its presence has been shown to determine whether or not an individual develops symptoms upon virus infection, and it leads to activation of the HPA axis. But, emotional stress is distinct from depression, the presence of which precludes a diagnosis of CFS. There is no specific treatment for CFS other than the much underutilised approach of specific treatment of virus infections. Current priorities are to understand the molecular pathogenesis of disease in terms of human and virus gene expression, to develop a diagnostic test based on protein biomarkers, and to develop specific curative treatments.

 

Source: Devanur LD, Kerr JR. Chronic fatigue syndrome.  J Clin Virol. 2006 Nov;37(3):139-50. Epub 2006 Sep 15. https://www.ncbi.nlm.nih.gov/pubmed/16978917

 

Current research priorities in chronic fatigue syndrome/myalgic encephalomyelitis: disease mechanisms, a diagnostic test and specific treatments

Abstract:

Chronic fatigue syndrome (CFS) is an illness characterised by disabling fatigue of at least 6 months duration, which is accompanied by various rheumatological, infectious and neuropsychiatric symptoms. A collaborative study group has been formed to deal with the current areas for development in CFS research–namely, to develop an understanding of the molecular pathogenesis of CFS, to develop a diagnostic test and to develop specific and curative treatments. Various groups have studied the gene expression in peripheral blood of patients with CFS, and from those studies that have been confirmed using polymerase chain reaction (PCR), clearly, the most predominant functional theme is that of immunity and defence. However, we do not yet know the precise gene signature and metabolic pathways involved. Currently, this is being dealt with using a microarray representing 47,000 human genes and variants, massive parallel signature sequencing and real-time PCR. It will be important to ensure that once a gene signature has been identified, it is specific to CFS and does not occur in other diseases and infections. A diagnostic test is being developed using surface-enhanced, laser-desorption and ionisation-time-of-flight mass spectrometry based on a pilot study in which putative biomarkers were identified. Finally, clinical trials are being planned; novel treatments that we believe are important to trial in patients with CFS are interferon-beta and one of the anti-tumour necrosis factor-alpha drugs.

 

Source: Kerr JR, Christian P, Hodgetts A, Langford PR, Devanur LD, Petty R, Burke B, Sinclair LI, Richards SC, Montgomery J, McDermott CR, Harrison TJ, Kellam P, Nutt DJ, Holgate ST; Collaborative Clinical Study Group. Current research priorities in chronic fatigue syndrome/myalgic encephalomyelitis: disease mechanisms, a diagnostic test and specific treatments. J Clin Pathol. 2007 Feb;60(2):113-6. Epub 2006 Aug 25. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860619/ (Full article)

 

Myalgic encephalomyelitis: a review with emphasis on key findings in biomedical research

Abstract:

This review examines research findings in patients with myalgic encephalomyelitis in light of the current debate about this chronic multiple-symptom, multiorgan, multisystem illness and the conflicting views in medicine. These issues cannot be separated from the political opinions and assertions that conflict with science and medicine, and will be part of this review as they have enormous consequences for scientific and medical research, patients, clinicians, carers and policy makers.

 

Source: Hooper M. Myalgic encephalomyelitis: a review with emphasis on key findings in biomedical research. J Clin Pathol. 2007 May;60(5):466-71. Epub 2006 Aug 25. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1994528/ (Full article)

 

A new look at chronic fatigue syndrome/myalgic encephalomyelitis

Abstract:

It has been 3 years since the Chief Medical Officer reported on chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) and the time has come for a thorough investigation by an All Party Group drawn from the House of Commons and the House of Lords. We have received many written submissions and are engaged in taking oral evidence in 2-h sessions, which we open to the public as well as interested groups. The group has received a fantastic response to its requests for written evidence over the past few months.

Questions that arise for a government response are the lack of provision and support for patients with CFS/ME, the issue of the clinical definition of CFS/ME, the need for a diagnostic test for CFS/ME, effectiveness of the National Institute for Clinical Excellence guidelines, and criteria used to decide which treatments are best for patients with CFS or myalgic encephalomyelitis.

 

Source: Gibson I. A new look at chronic fatigue syndrome/myalgic encephalomyelitis.J Clin Pathol. 2007 Feb;60(2):120-1. Epub 2006 Aug 25. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860614/ (Full article)

 

The debate: myalgic encephalomyelitis and chronic fatigue syndrome

Abstract:

Almost every aspect of myalgic encephalomyelitis (or encephalopathy) and chronic fatigue syndrome is the subject of disagreement and uncertainty — something that has undoubtedly hampered recognition, understanding and research. Although the pathogenesis remains the subject of intense medical debate, a number of predisposing, precipitating and perpetuating factors are now starting to emerge. Therapeutic nihilism is no longer appropriate as there is a great deal that can be done to alleviate some of the more distressing symptoms and improve quality of life for these patients.

 

Source: Shepherd C. The debate: myalgic encephalomyelitis and chronic fatigue syndrome. Br J Nurs. 2006 Jun 22-Jul 12;15(12):662-9. https://www.ncbi.nlm.nih.gov/pubmed/16835542

 

Chronic fatigue syndrome: an update focusing on phenomenology and pathophysiology

Abstract:

PURPOSE OF REVIEW: Chronic fatigue syndrome is a controversial condition especially concerning its clinical definition and aetiopathogenesis. Most recent research progress has been made in phenomenology and pathophysiology and we focused our review on these two areas.

RECENT FINDINGS: The phenomenology research supports the notion of a discrete fatigue syndrome which can be distinguished from depression and anxiety. The current case definition, however, may need an improvement based on empirical data. Recent advances in understanding the pathophysiology of chronic fatigue syndrome continue to demonstrate the involvement of the central nervous system. Hyperserotonergic state and hypoactivity of the hypothalamic-pituitary-adrenal axis constitute other findings, but the question of whether these alterations are a cause or consequence of chronic fatigue syndrome still remains unanswered. Immune system involvement in the pathogenesis seems certain but the findings on the specific mechanisms are still inconsistent. Genetic studies provide some evidence of the syndrome being a partly genetic condition, but environmental effects seem to be still predominant and identification of specific genes is still at a very early stage.

SUMMARY: The recent findings suggest that further research is needed in improving the current case definition; investigating overlaps and boundaries among various functional somatic syndromes; answering the question of whether the pathophysiologic findings are a cause or consequence; and elucidating the involvement of the central nervous system, immune system and genetic factors.

 

Source: Cho HJ, Skowera A, Cleare A, Wessely S. Chronic fatigue syndrome: an update focusing on phenomenology and pathophysiology. Curr Opin Psychiatry. 2006 Jan;19(1):67-73. https://www.ncbi.nlm.nih.gov/pubmed/16612182

 

Fibromyalgia and chronic fatigue syndrome: an update for athletic trainers

Abstract:

OBJECTIVE: Primary fibromyalgia syndrome (PFS) and chronic fatigue syndrome (CFS) are clinical conditions characterized by a variety of symptoms, including prominent fatigue, myalgia, and sleep disturbances. Although the incidence of these syndromes is infrequent, when manifested, they can completely disrupt the life and career of those affected. When they are manifested within the physically active population, they can jeopardize the futures of the most promising athletes.

DATA SOURCES: Public documents available from the U. S. Department of Health and Human Services, Public Health Services, and the National Institutes of Health were researched. MEDLINE and CINAHL were researched back to 1988 with the following key words: chronic fatigue syndrome, primary fibromyalgia syndrome, sports participant, physically active, mononucleosis, myalgia, rehabilitation, reconditioning, athlete, and sports medicine.

DATA SYNTHESIS: The definition of CFS in 1988 included disabling fatigue of unknown case of at least 6 months’ duration. Primary fibromyalgia syndrome was once considered a subsyndrome of CFS. PFS is diagnostically characterized as a nonarticular rheumatism. The “yuppie flu” was a catch phrase of the 1980s for CFS, which was then named chronic Epstein-Barr virus syndrome. Initially the condition was thought of as simple infectious mononucleosis, but we now have a medically defined set of symptoms to describe what are called CFS and PFS. Training interruptions, feelings of loss of control, and concerns over possible psychologic or psychiatric referral can occur. Relaxation therapy, exercise, image therapy, serotonin supplementation, and antiviral therapy are in clinical trials now as the best options for management of CFS and PFS.

CONCLUSIONS/RECOMMENDATIONS: Current statistics on those affected by CFS and PFS in the general population are less than 2% for CFS and 2% for PFS. Comprehensive documentation of signs, symptoms, and complaints, along with judicious physician follow-up, are important during the course of treatment leading up to and following a diagnosis of CFS or PFS. Professional evaluation of the affected player’s neuropsychological status is important and necessary as a care plan is developed.

 

Source: Cramer CR. Fibromyalgia and chronic fatigue syndrome: an update for athletic trainers. J Athl Train. 1998 Oct;33(4):359-61. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1320588/ (Full article)

 

Chronic fatigue syndrome

Abstract:

During the past two decades, there has been heated debate about chronic fatigue syndrome (CFS) among researchers, practitioners, and patients. Few illnesses have been discussed so extensively. The existence of the disorder has been questioned, its underlying pathophysiology debated, and an effective treatment opposed; patients’ organisations have participated in scientific discussions.

In this review, we look back on several controversies over CFS with respect to its definition, diagnosis, pathophysiology, and treatment. We review issues of epidemiology and clinical manifestations, focusing on the scientific status of CFS. Modern neuroscience and genetics research offer interesting findings for new hypotheses on the aetiology and pathogenesis of the illness. We also discuss promising future issues, such as psychopathophysiology and mechanisms of improvement, and suggest multidisciplinary prospective studies of CFS and fatigue in the general population. These studies should pay particular attention to similarities to and differences from functional somatic syndromes and other fatiguing conditions.

Comment in:

Chronic fatigue syndrome. [Lancet. 2006]

Chronic fatigue syndrome. [Lancet. 2006]

 

Source: Prins JB, van der Meer JW, Bleijenberg G. Chronic fatigue syndrome. Lancet. 2006 Jan 28;367(9507):346-55. https://www.ncbi.nlm.nih.gov/pubmed/16443043

 

Aetiology and pathogenesis of chronic fatigue syndrome: a review

Abstract:

Chronic fatigue syndrome (CFS) is a debilitating disease of uncertain aetiology that is characterised by unexplained, severe fatigue associated with a number of typical symptoms. This paper reviews the scientific literature related to current theories about the aetiology and pathogenesis of CFS by focussing on what appear to be the four most significant aspects in the development and perpetuation of this disease: the role of infectious agents as well as immunological, neuroendocrine, and psychiatric factors. A multifactorial model for the aetiology of CFS, which includes and draws together these four aspects, is proposed; and suggestions are offered regarding approaches to the diagnosis and treatment of this disease.

 

Source: Mihrshahi R, Beirman R. Aetiology and pathogenesis of chronic fatigue syndrome: a review. N Z Med J. 2005 Dec 16;118(1227):U1780. http://www.ncbi.nlm.nih.gov/pubmed/16372029