Chronic fatigue syndrome: aetiology, diagnosis and treatment

Abstract:

Chronic fatigue syndrome is characterised by intense fatigue, with duration of over six months and associated to other related symptoms. The latter include asthenia and easily induced tiredness that is not recovered after a night’s sleep. The fatigue becomes so severe that it forces a 50% reduction in daily activities.

Given its unknown aetiology, different hypotheses have been considered to explain the origin of the condition (from immunological disorders to the presence of post-traumatic oxidative stress), although there are no conclusive diagnostic tests.

Diagnosis is established through the exclusion of other diseases causing fatigue. This syndrome is rare in childhood and adolescence, although the fatigue symptom per se is quite common in paediatric patients.

Currently, no curative treatment exists for patients with chronic fatigue syndrome. The therapeutic approach to this syndrome requires a combination of different therapeutic modalities. The specific characteristics of the symptomatology of patients with chronic fatigue require a rapid adaptation of the educational, healthcare and social systems to prevent the problems derived from current systems. Such patients require multidisciplinary management due to the multiple and different issues affecting them.

This document was realized by one of the Interdisciplinary Work Groups from the Institute for Rare Diseases, and its aim is to point out the main social and care needs for people affected with Chronic Fatigue Syndrome. For this, it includes not only the view of representatives for different scientific societies, but also the patient associations view, because they know the true history of their social and sanitary needs. In an interdisciplinary approach, this work also reviews the principal scientific, medical, socio-sanitary and psychological aspects of Chronic Fatigue Syndrome.

 

Source: Avellaneda Fernández A1, Pérez Martín A, Izquierdo Martínez M, Arruti Bustillo M, Barbado Hernández FJ, de la Cruz Labrado J, Díaz-Delgado Peñas R, Gutiérrez Rivas E, Palacín Delgado C, Rivera Redondo J, Ramón Giménez JR. Chronic fatigue syndrome: aetiology, diagnosis and treatment. BMC Psychiatry. 2009 Oct 23;9 Suppl 1:S1. doi: 10.1186/1471-244X-9-S1-S1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2766938/ (Full article)

 

Central nervous system abnormalities in fibromyalgia and chronic fatigue syndrome: new concepts in treatment

Abstract:

Fibromyalgia (FM) and chronic fatigue syndrome (CFS) are poorly understood disorders that share similar demographic and clinical characteristics. The etiology and pathophysiology of these diseases remain unclear. Because of the similarities between both disorders it was suggested that they share a common pathophysiological mechanisms, namely, central nervous system (CNS) dysfunction. Current hypotheses center on atypical sensory processing in the CNS and dysfunction of skeletal muscle nociception and the hypothalamic-pituitary-adrenal (HPA) axis.

Researches suggest that the (CNS) is primarily involved in both disorders in regard to the pain, fatigue and sleep disturbances. Many patients experience difficulty with concentration and memory and many others have mood disturbance, including depression and anxiety. Although fibromyalgia is common and associated with substantial morbidity and disability, there are no US Food and Drug Administration (FDA)-approved treatments except pregabalin.

Recent pharmacological treatment studies about fibromyalgia have focused on selective serotonin and norepinephrine (NE) reuptake inhibitors, which enhance serotonin and NE neurotransmission in the descending pain pathways and lack many of the adverse side effects associated with tricyclic medications. CFS is a descriptive term used to define a recognisable pattern of symptoms that cannot be attributed to any alternative condition. The symptoms are currently believed to be the result of disturbed brain function.

To date, no pharmacological agent has been reliably shown to be effective treatment for CFS. Management strategies are therefore primarily directed at relief of symptoms and minimising impediments to recovery. This chapter presents data demonstrating CFS, abnormal pain processing and autonomic nervous system (ANS) dysfunction in FM and CFS and concludes by reviewing the new concepts in treatments in CFS and FM.

 

Source: Gur A, Oktayoglu P. Central nervous system abnormalities in fibromyalgia and chronic fatigue syndrome: new concepts in treatment. Curr Pharm Des. 2008;14(13):1274-94. https://www.ncbi.nlm.nih.gov/pubmed/18537652

 

Chronic fatigue syndrome: inflammation, immune function, and neuroendocrine interactions

Abstract:

Investigations into the underlying cause of chronic fatigue syndrome have advanced the field considerably in the past year. Gene microarray data have led to a better understanding of pathogenesis. Recent research has evaluated genetic signatures, described biologic subgroups, and suggested potential targeted treatments. Acute viral infection studies found that initial infection severity was the single best predictor of persistent fatigue. Genomic studies showed that persistent cases express Epstein Barr virus-specific genes and demonstrate abnormalities of mitochondrial function. Studies of immune dysfunction extended observations of natural killer cytotoxic cell dysfunction of the cytotoxic T cell through quantitative evaluation of intracellular perforins and granzymes. Other research has focused on a subgroup of patients with reactivated viral infection. These advances should result in targeted therapies that impact immune function, hypothalamic-pituitary-adrenal axis regulation, and persistent viral reactivation.

 

Source: Klimas NG, Koneru AO. Chronic fatigue syndrome: inflammation, immune function, and neuroendocrine interactions. Curr Rheumatol Rep. 2007 Dec;9(6):482-7. https://www.ncbi.nlm.nih.gov/pubmed/18177602

 

Chronic fatigue syndrome

Abstract:

INTRODUCTION: Chronic fatigue syndrome (CFS) affects between 0.006% and 3% of the population depending on the criteria of definition used, with women being at higher risk than men.

METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for chronic fatigue syndrome? We searched: Medline, Embase, The Cochrane Library, and other important databases up to September 2007 (BMJ Clinical evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS: We found 45 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS: In this systematic review we present information relating to the effectiveness and safety of the following interventions: antidepressants, cognitive behavioural therapy (CBT), corticosteroids, dietary supplements, evening primrose oil, galantamine, graded exercise therapy, homeopathy, immunotherapy, intramuscular magnesium, oral nicotinamide adenine dinucleotide, and prolonged rest.

 

Source: Reid SF, Chalder T, Cleare A, Hotopf M, Wessely S. Chronic fatigue syndrome. BMJ Clin Evid. 2008 Aug 28;2008. pii: 1101. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2907931/ (Full article)

 

Neuroaetiology of chronic fatigue syndrome: an overview

Abstract:

Chronic fatigue syndrome (CFS) is now recognized as a medial disorder. In contrast to recent related reports, the present review focuses primarily on aetiological aspects of CFS. Four major hypotheses are reviewed. (1) Although CFS is often associated with viral infection, the presence of viruses has as yet not consistently been detected. (2) It is not clear whether anomalies of the HPA axis often observed in CFS, are cause or the consequences of the disorder. (3) Immune dysfunction as the cause of CFS is thus far the weakest hypothesis. (4) The psychiatric and psychosocial hypothesis denies the existence of CFS as a disease entity. Accordingly, the fatigue symptoms are assumed to be the consequence of other (somatic) diseases. Other possible causes of CFS are oxidative stress and genetic predisposition. In CFS cognitive behavioural therapy is most commonly used. This therapy, however, appears to be ineffective in many patients. The suggested causes of CFS and the divergent reactions to therapy may be explained by the lack of recognition of subgroups. Identification of subtypes may lead to more effective therapeutic interventions.

 

Source: Sanders P, Korf J. Neuroaetiology of chronic fatigue syndrome: an overview. World J Biol Psychiatry. 2008;9(3):165-71. https://www.ncbi.nlm.nih.gov/pubmed/17853290

 

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)