Chronic fatigue syndrome: Difference between revisions

Jump to navigation Jump to search
VisualWikitext
No edit summary
 
Line 13: Line 13:
   MeshID        = D015673 |
   MeshID        = D015673 |
}}
}}
{{Search infobox}}
{{Chronic fatigue syndrome}}
{{CMG}}
{{CMG}}


==Overview==
==[[Chronic fatigue syndrome overview|Overview]]==
'''Chronic fatigue syndrome''' ('''CFS''') is [[ME/CFS nomenclatures|one of several names]] given to a poorly understood, variably debilitating disorder of uncertain [[etiology|causation]]. CFS is thought, based on a 1999 study, to affect approximately 4 per 1,000 adults in the United States.<ref name=pmid10527290>{{cite journal |author=Jason LA, Richman JA, Rademaker AW, Jordan KM, Plioplys AV, Taylor RR, McCready W, Huang CF, Plioplys S |title=A community-based study of chronic fatigue syndrome |journal=Arch. Intern. Med. |volume=159 |issue=18 |pages=2129–37 |year=1999 | url = http://archinte.ama-assn.org/cgi/content/full/159/18/2129 |pmid=10527290 | doi = 10.1001/archinte.159.18.2129 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
For unknown reasons, CFS occurs more often in women than men, and in people in their 40s and 50s.<ref>{{cite journal |author=Gallagher AM, Thomas JM, Hamilton WT, White PD |title=Incidence of fatigue symptoms and diagnoses presenting in UK primary care from 1990 to 2001 |journal=J R Soc Med |volume=97 |issue=12 |pages=571–5 |year=2004 |pmid=15574853 |doi=10.1258/jrsm.97.12.571}}</ref><ref name="CDCRisk"/> The illness is estimated to be less prevalent among children and adolescents, but studies are contradictory as to the degree.<ref name="DOI : 10.1300/J092v13n02_01">{{cite journal |author=Jason LA, Jordan K, Miike T, Bell DS, Lapp C, Torres-Harding S, Rowe K, Gurwitt A, De Meirleir K, Van Hoof ELS |title=A Pediatric Case Definition for Myalgic Encephalomyelitis and Chronic Fatigue Syndrome |journal=Journal of Chronic Fatigue Syndrome |volume=13 |issue=2-3 | pages = 1–44 |year=2006| doi = 10.1300/J092v13n02_01}}</ref>


CFS often manifests with widespread [[myalgia]] and [[arthralgia]], cognitive difficulties, chronic mental and physical exhaustion, often severe, and other characteristic symptoms in a previously healthy and active person. Despite promising avenues of [[medical research|research]], there remains no [[medical test|assay]] or [[pathology|pathological]] finding which is widely accepted to be diagnostic of CFS. It remains a [[diagnosis of exclusion]] based largely on patient history and [[symptom]]atic criteria, although a number of tests can aid diagnosis.<ref name="carr">{{cite journal | author = Carruthers BM, Jain AK, De Meirleir KL, Peterson DL, Klimas MD, Lerner AM, Bested AC, Flor-Henry P, Joshi P, Powles ACP, Sherkey JA, van de Sande MI | title = Myalgic encephalomyalitis/chronic fatigue syndrome: Clinical working definition, diagnostic and treatment protocols | journal = Journal of Chronic Fatigue Syndrome | volume = 11 | issue = 1 | pages = 7–36 | year = 2003 | url = http://www.cfids-cab.org/MESA/me_overview.pdf | doi = 10.1300/J092v11n01_02}}</ref> Whereas there is agreement on the genuine threat to health, happiness, and productivity posed by CFS, various [[physician|physicians']] groups, researchers, and patient activists champion very different nomenclature, diagnostic criteria, etiologic hypotheses, and treatments, resulting in controversy about nearly all aspects of the disorder. Even the term ''chronic fatigue syndrome'' is controversial because a large part of the patient community believes the name trivializes the illness.<ref name="Jason">{{cite journal|author=Jason LA, Taylor RR| year=2001|title= Measuring Attributions About Chronic Fatigue Syndrome|journal=J Chronic Fatigue Syndr| volume=8|issue=3/4 |pages=31–40 |url=http://www.cfids-cab.org/cfs-inform/Welcome/jason.taylor01.txt |format=TXT|doi= 10.1300/J092v08n03_04}}</ref>
==[[Chronic fatigue syndrome historical perspective|Historical Perspective]]==


''Chronic fatigue syndrome'' is not the same as "chronic fatigue".<ref name="carr"/> Fatigue is a common symptom in many illnesses, but CFS is a multi-systemic disease and is relatively rare by comparison.<ref name="PMID_15699086">{{cite journal | author = Ranjith G | title = Epidemiology of chronic fatigue syndrome. | journal = Occup Med (Lond) | volume = 55 | issue = 1 | pages = 13–9 | year = 2005 | pmid = 15699086 | doi = 10.1093/occmed/kqi012 <!--Retrieved from CrossRef by DOI bot-->}}</ref> [[#Diagnosis|Definitions]] (other than the 1991 [[United Kingdom|UK]] Oxford criteria)<ref name="oxford">{{cite journal | author = Sharpe M, Archard L, Banatvala J, Borysiewicz L, Clare A, David A, Edwards R, Hawton K, Lambert H, Lane R | title = A report--chronic fatigue syndrome: guidelines for research | journal = J R Soc Med | volume = 84 | issue = 2 | pages = 118–21 | year = 1991 | pmid= 1999813}} {{PMC|1293107}} Synopsis by {{GPnotebook|-476446699|Oxford criteria for the diagnosis of chronic fatigue syndrome}})</ref> require a number of features, the most common being severe mental and physical exhaustion which is "unrelieved by rest" (1994 Fukuda definition),<ref name="CDC1994">{{cite journal | author = Fukuda K, Straus S, Hickie I, Sharpe M, Dobbins J, Komaroff A | title = The chronic fatigue syndrome: a comprehensive approach to its definition and study. International Chronic Fatigue Syndrome Study Group. | journal = Ann Intern Med | volume = 121 | issue = 12 | pages = 953–9 | year = 1994 | pmid=7978722|url=http://www.annals.org/cgi/content/full/121/12/953}}</ref> and may be worsened by even trivial exertion (a mandatory diagnostic criterion according to some systems). Most diagnostic criteria require that symptoms must be present for at least six months, and all state the symptoms must not be caused by other medical conditions. CFS patients may report many symptoms which are not included in all diagnostic criteria, including [[muscle weakness]], [[cognitive]] dysfunction, [[hypersensitivity]], [[orthostatic intolerance]], digestive disturbances, [[clinical depression|depression]], poor [[immune response]], and [[cardiac]] and [[Respiratory system|respiratory]] problems. It is unclear if these symptoms represent co-morbid conditions or are produced by an underlying etiology of CFS.<ref name="pmid:12562565">{{cite journal |author=Afari N, Buchwald D |title=Chronic fatigue syndrome: a review |journal=Am J Psychiatr |volume=160 |issue=2 |pages=221–36 |year=2003 |pmid=12562565 |url=http://ajp.psychiatryonline.org/cgi/content/full/160/2/221 | doi = 10.1176/appi.ajp.160.2.221 <!--Retrieved from CrossRef by DOI bot-->}}</ref> Some cases improve over time, and treatments (though none are universally accepted) bring a degree of improvement to many others, though full resolution may be only 5-10% according to the United States [[Centers for Disease Control and Prevention]] (CDC).<ref name="CDCBasic"/>
==[[Chronic fatigue syndrome pathophysiology|Pathophysiology]]==


==Nomenclature==
==[[Chronic fatigue syndrome epidemiology and demographics|Epidemiology & Demographics]]==
{{Main|ME/CFS nomenclatures}}
The naming of this condition has been challenging, since consensus is lacking within the clinical, research, and patient communities regarding its defining features and causes. Authorities on it do not agree if it is a central nervous system, metabolic, (post-)infectious, immune system, or neuropsychiatric disorder, nor even if it is a single homogenous disorder (with a range of possible clinical presentations), or several distinct disorders having many clinical characteristics in common.


Over time and in different countries many names have been associated with the condition(s). Some of the more common names in use include:<ref name="isbn0-9695662-0-4X">{{cite book |author=Byron M. Hyde |title=The Clinical and scientific basis of myalgic encephalomyelitis/chronic fatigue syndrome |publisher=Nightingale Research Foundation |location=Ogdensburg, N.Y |year=1992 |pages=X |isbn = 0969566204}}</ref>
==[[Chronic fatigue syndrome risk factors|Risk Factors]]==


*[[ME/CFS nomenclatures#Myalgic_encephalomyelitis|Myalgic Encephalomyelitis (ME)]]
==[[Chronic fatigue syndrome causes|Causes of Chronic fatigue syndrome]]==
*[[ME/CFS nomenclatures#Chronic_fatigue_syndrome|Chronic Fatigue Syndrome (CFS)]]
*[[Post-viral fatigue syndrome|Post-Viral Fatigue Syndrome (PVFS)]]
*[[ME/CFS nomenclatures#Chronic_fatigue_immune_dysfunction_syndrome_.28CFIDS.29|Chronic Fatigue Immune Dysfunction Syndrome (CFIDS)]]


==Signs and symptoms==
==[[Chronic fatigue syndrome differential diagnosis|Differentiating Chronic fatigue syndrome from other Diseases]]==


As the name chronic fatigue syndrome suggests, this illness is accompanied by fatigue. However, it's not the kind of fatigue patients experience after a particularly busy day or week, after a sleepless night or after a stressful event. It's a severe, incapacitating fatigue that isn't improved by bed rest and that may be exacerbated by physical or mental activity. It's an all-encompassing fatigue that results in a dramatic decline in both activity level and stamina.
==[[Chronic fatigue syndrome natural history|Natural History, Complications & Prognosis]]==


People with CFS function at a significantly lower level of activity than they were capable of prior to becoming ill. The illness results in a substantial reduction in occupational, personal, social or educational activities.
==Diagnosis==
[[Chronic fatigue syndrome history and symptoms|History & Symptoms]] | [[Chronic fatigue syndrome physical examination|Physical Examination]] | [[Chronic fatigue syndrome laboratory tests|Lab Tests]]


Chronic fatigue syndrome shares symptoms with many other disorders. Fatigue, for instance, is found in hundreds of illnesses, and 10% to 25% of all patients who visit general practitioners complain of prolonged fatigue. The nature of the symptoms, however, can help clinicians differentiate CFS from other illnesses.
==[[Chronic fatigue syndrome medical therapy|Treatment]]==


A CFS diagnosis should be considered in patients who present with six months or more of unexplained fatigue accompanied by other characteristic symptoms. These symptoms include:
==Related chapters==
*[[Mononucleosis|Chronic EBV infection]]


* cognitive dysfunction, including impaired memory or concentration
* postexertional malaise lasting more than 24 hours (exhaustion and increased symptoms) following physical or mental exercise
* unrefreshing sleep
* joint pain (without redness or swelling)
* persistent muscle pain
* headaches of a new type or severity
* tender cervical or axillary lymph nodes
* sore throat
'''Other Common Symptoms'''
In addition to the eight primary defining symptoms of CFS, a number of other symptoms have been reported by some CFS patients. The frequency of occurrence of these symptoms varies among patients. These symptoms include:
* irritable bowel, abdominal pain, nausea, diarrhea or bloating
* chills and night sweats
* brain fog
* [[chest pain]]
* shortness of breath
* chronic [[cough]]
* visual disturbances (blurring, sensitivity to light, eye pain or dry eyes)
* allergies or sensitivities to foods, alcohol, odors, chemicals, medications or noise
* difficulty maintaining upright position (orthostatic instability, irregular heartbeat, dizziness, balance problems or fainting)
* psychological problems (depression, irritability, mood swings, anxiety, panic attacks)
* jaw pain
* weight loss or gain
Clinicians will need to consider whether such symptoms relate to a comorbid or an exclusionary condition; they should not be considered as part of CFS other than they can contribute to impaired functioning.
===Onset===
====Sudden onset cases====
The majority of CFS cases start suddenly,<ref name="PMID_9201648"/> usually accompanied by a "flu-like illness"<ref name="pmid:12562565"/><ref>{{cite journal | author = Sairenji T, Nagata K | title = Viral infections in chronic fatigue syndrome. | journal = Nippon Rinsho | volume = 65 | issue = 6 | pages = 991–6 | year = 2007 | pmid= 17561687}}</ref><ref>{{cite journal | author = Evengård B, Jonzon E, Sandberg A, Theorell T, Lindh G | title = Differences between patients with chronic fatigue syndrome and with chronic fatigue at an infectious disease clinic in Stockholm, Sweden. | journal = Psychiatry Clin Neurosci | volume = 57 | issue = 4 | pages = 361–8 | year = 2003 | pmid= 12839515 | doi = 10.1046/j.1440-1819.2003.01132.x <!--Retrieved from CrossRef by DOI bot-->}}</ref><ref>{{cite journal | author = Evengård B, Schacterle RS, Komaroff AL | title = Chronic fatigue syndrome: new insights and old ignorance. | journal = J Intern Med | volume = 246 | issue = 5 | pages = 455–69 | year = 1999 | pmid= 10583715 | doi = 10.1046/j.1365-2796.1999.00513.x <!--Retrieved from CrossRef by DOI bot-->}}</ref> which is more likely to occur in winter,<ref>{{cite journal | author = Jason LA, Taylor RR, Carrico AW | title = A community-based study of seasonal variation in the onset of chronic fatigue syndrome and idiopathic chronic fatigue. | journal = Chronobiol Int | volume = 18 | issue = 2 | pages = 315–9 | year = 2001 | pmid= 11379670 | doi = 10.1081/CBI-100103194 <!--Retrieved from CrossRef by DOI bot-->}}</ref><ref>{{cite journal | author = Zhang QW, Natelson BH, Ottenweller JE, Servatius RJ, Nelson JJ, De Luca J, Tiersky L, Lange G | title = Chronic fatigue syndrome beginning suddenly occurs seasonally over the year. | journal = Chronobiol Int | volume = 17 | issue = 1 | pages = 95–9 | year = 2000 | pmid= 10672437 | doi = 10.1081/CBI-100101035 <!--Retrieved from CrossRef by DOI bot-->}}</ref> while a significant proportion of cases begin within several months of severe adverse stress.<ref>{{cite journal | author = Hatcher S, House A | title = Life events, difficulties and dilemmas in the onset of chronic fatigue syndrome: a case-control study. | journal = Psychol Med | volume = 33 | issue = 7 | pages = 1185–92 | year = 2003 | pmid= 14580073 | doi = 10.1017/S0033291703008274 <!--Retrieved from CrossRef by DOI bot--> | unused_data = |url: http://eprints.whiterose.ac.uk/1226/1/house3.pdf}}</ref><ref name="PMID_10367610">{{cite journal | author = Theorell T, Blomkvist V, Lindh G, Evengard B | title = Critical life events, infections, and symptoms during the year preceding chronic fatigue syndrome (CFS): an examination of CFS patients and subjects with a nonspecific life crisis. | journal = Psychosom Med. | volume = 61 | issue = 3 | pages = 304–10 | pmid= 10367610}}</ref><ref name="PMID_9201648">{{cite journal | author = Salit IE | title = Precipitating factors for the chronic fatigue syndrome. | journal = J Psychiatr Res | volume = 31 | issue = 1 | pages = 59–65 | year = 1997 | pmid= 9201648 | doi = 10.1016/S0022-3956(96)00050-7 <!--Retrieved from CrossRef by DOI bot-->}}</ref> Many people report getting a case of a [[influenza|flu]]-like or other [[respiratory infection]] such as [[bronchitis]], from which they seem never to fully recover and which evolves into CFS. The diagnosis of [[Post-viral fatigue syndrome]] is sometimes given in the early stage of the illness.<ref name="pmid16950834">{{cite journal |author=Hickie I, Davenport T, Wakefield D, ''et al'' |title=Post-infective and chronic fatigue syndromes precipitated by viral and non-viral pathogens: prospective cohort study |journal=BMJ |volume=333 |issue=7568 |pages=575 |year=2006 |pmid=16950834 |doi=10.1136/bmj.38933.585764.AE}}</ref> One study reported CFS occurred in some patients following a [[vaccination]] or a [[blood transfusion]].<ref name="Becker02">{{cite journal | author =  De Becker P, McGregor N, De Meirleir K | title = Possible Triggers and Mode of Onset of Chronic Fatigue Syndrome | journal = Journal of Chronic Fatigue Syndrome | volume = 10 | issue = 2 | pages = 2–18 | year = 2002 | doi = 10.1300/J092v10n02_02}}</ref> The accurate prevalence and exact roles of infection and stress in the development of CFS however are currently unknown.
====Gradual onset cases====
Other cases have a gradual onset, sometimes spread over years.<ref name="Becker02"/> Patients with [[Lyme disease]] may, despite a standard course of treatment, "evolve" clinically from the symptoms of acute Lyme to those similar to CFS.<ref>{{cite journal | author = Donta S | title = Late and chronic Lyme disease. | journal = Med Clin North Am | volume = 86|issue = 2|pages = 341–9, vii|year = 2002|pmid= 11982305 | doi = 10.1016/S0025-7125(03)00090-7 <!--Retrieved from CrossRef by DOI bot-->}}</ref> This has become [[Lyme disease controversy|an area of great controversy]].
===Course===
The severity of CFS varies from patient to patient, with some people able to maintain fairly active lives. By definiton, however, CFS significantly limits work, school and family activities.
While symptoms vary from person to person in number, type and severity, all CFS patients are functionally impaired to some degree. CDC studies show that CFS can be as disabling as multiple sclerosis, lupus, rheumatoid arthritis, heart disease, end-stage renal disease, chronic obstructive pulmonary disease (COPD) and similar chronic conditions.
CFS often follows a cyclical course, alternating between periods of illness and relative well-being. Some patients experience partial or complete remission of symptoms during the course of the illness, but symptoms often reoccur. This pattern of remission and relapse makes CFS especially hard for patients and their health care professionals to manage. Patients who are in remission may be tempted to overdo activities when they're feeling better, which can exacerbate symptoms and fatigue and cause a relapse. In fact, postexertional malaise is a hallmark of the illness.
The percentage of CFS patients who recover is unknown, but there is some evidence to indicate that the sooner symptom management begins, the better the chance of a positive therapeutic outcome. This means early detection and treatment are of utmost importance. CDC research indicates that delays in diagnosis and treatment may complicate and prolong the clinical course of the illness.
It can be inferred from the 2003 Canadian clinical working definition of ME/CFS<ref name="carr"/> that there are 8 categories of symptoms:
* [[Fatigue (physical)|Fatigue]]: Unexplained, persistent, or recurrent physical and mental fatigue/[[exhaustion]] that substantially reduces activity levels and is not relieved (or not completely relieved) by rest.
* Post-exertional [[malaise]]: An inappropriate loss of physical and mental stamina, rapid muscular and cognitive fatigability, post exertional malaise and/or fatigue and/or pain and a tendency for other associated symptoms to worsen with a pathologically slow recovery period of usually 24 hours or longer. According to the authors of the Canadian clinical working definition of ME/CFS,<ref name="carr"/> the malaise that follows exertion is often reported to be similar to the generalized pain, discomfort and fatigue associated with the acute phase of influenza. Although common in CFS, this may not be the most severe symptom in the individual case, where other symptoms (such as headaches, neurocognitive difficulties, pain and sleep disturbances) can dominate.
* [[Dyssomnia|Sleep dysfunction]]: "Unrefreshing" sleep/rest, poor sleep quantity, [[insomnia]] or rhythm disturbances. A study found that most CFS patients have clinically significant sleep abnormalities that are potentially treatable.<ref>{{cite journal | author = Krupp LB, Jandorf L, Coyle PK, Mendelson WB | title = Sleep disturbance in chronic fatigue syndrome. | journal = J Psychosom Res | volume = 37 | issue = 4 | pages = 325–31 | year = 1993 | pmid= 8510058 | doi = 10.1016/0022-3999(93)90134-2 <!--Retrieved from CrossRef by DOI bot-->}}</ref> Several studies suggest that while CFS patients may experience altered sleep architecture (such as reduced sleep efficiency, a reduction of deep sleep, prolonged sleep initiation, and alpha-wave intrusion during deep sleep) and mildly disordered breathing, overall sleep dysfunction does not seem to be a critical or causative factor in CFS.<ref>{{cite journal | author = Reeves WC, Heim C, Maloney EM, Youngblood LS, Unger ER, Decker MJ, Jones JF, Rye DB | title = Sleep characteristics of persons with chronic fatigue syndrome and non-fatigued controls: results from a population-based study. | journal = BMC Neurol | volume = 6 | pages = 41 | year = 2006 | pmid=17109739 | doi = 10.1186/1471-2377-6-41 <!--Retrieved from CrossRef by DOI bot-->}}</ref><ref>{{cite journal | author = Watson NF, Kapur V, Arguelles LM, Goldberg J, Schmidt DF, Armitage R, Buchwald D | title = Comparison of subjective and objective measures of insomnia in monozygotic twins discordant for chronic fatigue syndrome. | journal = Sleep | volume = 26 | issue = 3 | pages = 324–8 | year = 2003 | pmid= 12749553}}</ref><ref name = "VanHoof2007">{{cite journal | author = Van Hoof E, De Becker P, Lapp C, Cluydts R, De Meirleir K | title = Defining the occurrence and influence of alpha-delta sleep in chronic fatigue syndrome. | journal = Am J Med Sci | volume = 333 | issue = 2 | pages = 78–84 | year = 2007 | pmid=17301585 | doi = 10.1097/00000441-200702000-00003}}</ref><ref>{{cite journal | author = Ball N, Buchwald DS, Schmidt D, Goldberg J, Ashton S, Armitage R | title = Monozygotic twins discordant for chronic fatigue syndrome: objective measures of sleep. | journal = J Psychosom Res | volume = 56 | issue = 2 | pages = 207–12 | year = 2004 | pmid= 15016580 | doi = 10.1016/S0022-3999(03)00598-1 <!--Retrieved from CrossRef by DOI bot-->}}</ref> Sleep may present with vivid disturbing dreams, and exhaustion can worsen sleep dysfunction.<ref name="carr2">"Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Clinical Case Definition and Guidelines for Medical Practitioners - An Overview of the Canadian Consensus Document"; authored by Carruthers and van de Sande; published in 2005, ISBN 0-9739335-0-X, [http://www.mefmaction.net/documents/me_overview.pdf PDF]</ref>
* [[Pain]]: Pain is often widespread and migratory in nature, including a significant degree of [[myalgia|muscle pain]] and/or [[arthralgia|joint pain]] (without joint swelling or redness, and may be transitory). Other symptoms include [[headache]]s (particularly of a new type, severity, or duration), [[lymph node]] pain, [[sore throat]]s, and [[abdominal pain]] (often as a symptom of [[irritable bowel syndrome]]). Patients also report bone, eye and [[Orchalgia|testicular pain]], [[neuralgia|nerve pain]] and painful skin sensitivity. [[Chest pain]] has been attributed variously to [[microvascular disease]] or [[cardiomyopathy]] by researchers, and many patients also report painful [[tachycardia]]. A systematic review assessing the studies of chronic pain in CFS found that although the exact prevalence is unknown, it is strongly disabling in patients, but unrelated to depression.<ref name="PMID_16843021">{{cite journal | author = Meeus M, Nijs J, Meirleir KD | title = Chronic musculoskeletal pain in patients with the chronic fatigue syndrome: A systematic review. | journal = Eur J Pain | volume = 11 | issue = 4 | pages = 377–386 | year = 2007 | pmid= 16843021 | doi = 10.1016/j.ejpain.2006.06.005 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
* [[Neurological]]/[[cognitive]] manifestations: Common occurrences include [[confusion]], [[forgetfulness]], mental fatigue/[[brain fog]], impairment of concentration and short-term memory consolidation, disorientation, difficulty with information processing, categorizing and word retrieval, and perceptual and sensory disturbances (e.g. spatial instability and disorientation and inability to focus vision), [[ataxia]] (unsteady and clumsy motion of the limbs or torso), muscle weakness and "twitches". There may also be cognitive or sensory overload (e.g. photophobia and hypersensitivity to noise and/or emotional overload, which may lead to "crash" periods and/or anxiety). A review of research relating to the neuropsychological functioning in CFS was published in 2001 and found that slowed processing speed, impaired working memory and poor learning of information are the most prominent features of cognitive dysfunctioning in patients with CFS, which couldn't be accounted solely by the severity of the depression and anxiety.<ref>{{cite journal | author = Michiels V, Cluydts R | title = Neuropsychological functioning in chronic fatigue syndrome: a review. | journal = Acta Psychiatr Scand | volume = 103 | issue = 2 | pages = 84–93 | year = 2001 | pmid= 11167310 | doi = 10.1034/j.1600-0447.2001.00017.x <!--Retrieved from CrossRef by DOI bot-->}}</ref>
* [[Autonomic nervous system|Autonomic]] manifestations: Common occurrences include [[orthostatic intolerance]], neurally mediated [[hypotension]] (NMH), [[postural orthostatic tachycardia syndrome]] (POTS), delayed postural [[hypotension]], [[lightheadedness]], extreme [[pallor]], [[nausea]] and [[irritable bowel syndrome]], urinary frequency and bladder dysfunction, [[palpitation]]s with or without [[cardiac arrhythmia]]s, and exertional [[dyspnea]] (perceived difficulty breathing or pain on breathing).
* [[Neuroendocrine]] manifestations: Common occurrences include poor [[thermoregulation|temperature control]] or loss of thermostatic stability, subnormal body temperature and marked daily fluctuation, sweating episodes, recurrent feelings of feverishness and cold extremities, intolerance of extremes of heat and cold, digestive disturbances<ref>{{cite journal | author = Burnet RB, Chatterton BE | title = Gastric emptying is slow in chronic fatigue syndrome. | journal = BMC Gastroenterol | volume = 4 | pages = 32 | year = 2004 | pmid= 15619332 | doi=10.1186/1471-230X-4-32}}</ref> and/or marked weight change - anorexia or abnormal appetite, loss of adaptability and worsening of symptoms with stress.
* [[Immune]] manifestations: Common occurrences include tender lymph nodes, recurrent sore throat, recurrent flu-like symptoms, general malaise, new sensitivities to food and/or medications and/or chemicals (which may complicate treatment). At least one study has confirmed that most CFS patients reduce or cease alcohol intake, mostly due to personal experience of worsening symptoms<ref>{{cite journal | author = Woolley J, Allen R, Wessely S | title = Alcohol use in chronic fatigue syndrome. | journal = J Psychosom Res | volume = 56 | issue = 2 | pages = 203–6 | year = 2004 | pmid= 15016579 | doi = 10.1016/S0022-3999(03)00077-1 <!--Retrieved from CrossRef by DOI bot-->}}</ref> (although the cause of this is unknown and may not be strictly "immunological" as implied by the symptom list).
===Activity levels===
Patients report critical reductions in levels of physical activity<ref name="PMID_8771284">{{cite journal | author = McCully KK, Sisto SA, Natelson BH | title = Use of exercise for treatment of chronic fatigue syndrome. | journal = Sports Med | volume = 21 | issue = 1 | pages = 35–48 | year = 1996 | pmid= 8771284 | doi = 10.2165/00007256-199621010-00004 <!--Retrieved from CrossRef by DOI bot-->}}</ref> and are as impaired as persons whose fatigue can be explained by another medical or a psychiatric condition.<ref name="PMID_14577835">{{cite journal | author = Solomon L, Nisenbaum R, Reyes M, Papanicolaou DA, Reeves WC | title = Functional status of persons with chronic fatigue syndrome in the Wichita, Kansas, population. | journal = Health Qual Life Outcomes | volume = 1 | issue = 1 | pages = 48 | year = 2003 | pmid= 14577835 | doi =  10.1186/1477-7525-1-48}} {{PMC|239865}}</ref> According to the CDC, studies show that the disability in CFS patients is comparable to some well-known, very severe medical conditions, such as; [[multiple sclerosis]], [[AIDS]], [[Lupus erythematosus|lupus]], [[rheumatoid arthritis]], [[heart disease]], end-stage [[renal disease]], [[chronic obstructive pulmonary disease]] (COPD) and similar chronic conditions.<ref>Press Conference: [http://www.cdc.gov/od/oc/media/transcripts/t061103.htm?id=36410 The Chronic Fatigue and Immune Dysfunction Syndrome Association of America and The Centers For Disease Control and Prevention Press Conference at The National Press Club to Launch a Chronic Fatigue Syndrome Awareness Campaign] - [[November 3]] [[2006]]</ref><ref>[http://www.cdc.gov/cfs/cfssymptomsHCP.htm The Centers For Disease Control and Prevention (website): Chronic Fatigue Syndrome > For Healthcare Professionals > Symptoms > Clinical Course]</ref> The severity of symptoms and disability is the same in both genders,<ref>{{cite journal | author = Ho-Yen DO, McNamara I | title = General practitioners' experience of the chronic fatigue syndrome | journal = Br J Gen Pract | volume = 41 | issue = 349 | pages = 324–6 | year = 1991 | pmid= 1777276}}</ref> and chronic pain is strongly disabling in CFS patients,<ref name="PMID_16843021" /> but despite a common diagnosis the functional capacity of CFS patients varies greatly.<ref name="PMID_12783037">{{cite journal | author = Vanness JM, Snell CR, Strayer DR, Dempsey L 4th, Stevens SR | title = Subclassifying chronic fatigue syndrome through exercise testing. | journal = Med Sci Sports Exerc | volume = 35 | issue = 6 | pages = 908–13 | year = 2003 | pmid= 12783037 | doi = 10.1249/01.MSS.0000069510.58763.E8 <!--Retrieved from CrossRef by DOI bot-->}}</ref> While some patients are able to lead a relatively normal life, others are totally bed-bound and unable to care for themselves. A systematic review found that in a synthesis of studies, 42% of patients were employed, 54% were unemployed, 64% reported CFS-related work limitations, 55% were on disability benefits or temporary sick leave, and 19% worked full-time.<ref>{{cite journal | author = Ross SD, Estok RP, Frame D, Stone LR, Ludensky V, Levine CB | title = Disability and chronic fatigue syndrome: a focus on function. | journal = Arch Intern Med | volume = 164 | issue = 10 | pages = 1098–107 | year = 2004 | pmid= 15159267 | url = http://archinte.ama-assn.org/cgi/content/full/164/10/1098 | doi = 10.1001/archinte.164.10.1098 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
==Pathophysiology==
{{Main|ME/CFS pathophysiology}}
The mechanisms and processes ([[pathogenesis]]) of Chronic Fatigue Syndrome are gradually being revealed through research, including [[physiological]] and [[epidemiological]] studies. In a basic overview of CFS for health professionals, the CDC states that "''After more than 3,000 research studies, there is now abundant scientific evidence that CFS is a real physiological illness.''"<ref name="CDC Basic Overview">{{cite web | last = | first = | authorlink = | coauthors = | title = CFS Toolkit for Health Care Professionals: Basic CFS Overview | work = | publisher = U.S. Department of Health and Human Services, Centers for Disease Control and Prevention | date = | url = http://www.cdc.gov/cfs/pdf/Basic_Overview.pdf | format = PDF file, 31 KB | doi = | accessdate = 2008-03-19}}</ref>
Chronic fatigue syndrome (CFS) or (ME) has been described in a 2008 ''Toxicology'' journal article as, "a constellation of multi-system dysfunctions primarily involving the neurological ([[nervous system]]), endocrine ([[hormone system]]), and [[immune system]]s." The article states recent research suggests the potential that [[xenobiotic]] (chemicals), [[infectious agents]], [[stress (medicine)|stress]], and other insults in early-life may be a component of later-life CFS.<ref name="PMID_18336982">{{cite journal | last = Dietert | first = RR | coauthors = Dietert JM | title = Possible role for early-life immune insult including developmental immunotoxicity in chronic fatigue syndrome (CFS) or myalgic encephalomyelitis (ME) | journal = Toxicology | volume = | issue = | pages = | publisher = | location = | date = 2008 Feb 8 |pmid = 18336982}}</ref>
A 2007 article in the journal ''Autoimmunity'' summarised; “The current concept is that CFS pathogenesis is a multi factorial condition in which an infective agent cause an aberrant [[immune response]] characterized by a shift to Th-2 ([[cytokine]]) dominant response. When the response fails to be switched-off, a chronic immune activation occurs and is clinically expressed in the symptomatology of CFS". <ref name="pmid17364497">{{cite journal |author=Appel S, Chapman J, Shoenfeld Y |title=Infection and vaccination in chronic fatigue syndrome: myth or reality? |journal=Autoimmunity |volume=40 |issue=1 |pages=48–53 |year=2007 |pmid=17364497 |doi=10.1080/08916930701197273}}</ref>
In a 2006 update in the journal ''Curr Opin Psychiatry'' it was said; “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]] (HPA axis) constitute other findings, but the question of whether these alterations are a cause or consequence of chronic fatigue syndrome still remains unanswered.” <ref name="pmid16612182">{{cite journal |author=Cho HJ, Skowera A, Cleare A, Wessely S |title=Chronic fatigue syndrome: an update focusing on phenomenology and pathophysiology |journal=Curr Opin Psychiatry |volume=19 |issue=1 |pages=67–73 |year=2006 |pmid=16612182 |doi=10.1097/01.yco.0000194370.40062.b0}}</ref> . Alterations in [[serotonin]] signaling can lead to physiologic and behavioral changes. A 2008 study of gene [[polymorphisms]] indicates [[genetic predisposition]] possibly resulting in enhanced activity of serotonin may be involved in the pathophysiology of CFS. <ref name="pmid18079067">{{cite journal |author=Smith AK, Dimulescu I, Falkenberg VR, ''et al'' |title=Genetic evaluation of the serotonergic system in chronic fatigue syndrome |journal=Psychoneuroendocrinology |volume=33 |issue=2 |pages=188–97 |year=2008 |pmid=18079067 |doi=10.1016/j.psyneuen.2007.11.001}}</ref>
Chronic fatigue is a typical symptom of [[neurological]] diseases, including chronic fatigue syndrome, is also seen in diseases that affect the [[central nervous system|central]], [[peripheral nervous system|peripheral]], and [[autonomic nervous system]]s (central fatigue). Enhanced perception of effort and limited endurance of sustained physical and mental activities are the main characteristics of central fatigue.  Metabolic and structural lesions can cause muscle fatigability (peripheral fatigue) also disrupt the usual process of activation in pathways interconnecting the [[basal ganglia]] (peripheral nerves), [[thalamus]], [[limbic system]], and higher [[cortical]] centre are implicated in the pathophysiological process of central fatigue. A state of low cortisol might sensitize the [[hypothalamic-pituitary-adrenal axis]] (HPA axis) to development of persistent central fatigue after stress. <ref name="pmid15043967">{{cite journal |author=Chaudhuri A, Behan PO |title=Fatigue in neurological disorders |journal=Lancet |volume=363 |issue=9413 |pages=978–88 |year=2004 |pmid=15043967 |doi=10.1016/S0140-6736(04)15794-2}}</ref>
Chronic Fatigue Syndrome (CFS) is a disorder whose etiology and pathogenesis are still unknown. In this syndrome both abnormalities of nervous and immune systems have been reported. Nervous and immune systems mutually cooperate via release of mediators of both [[neurological]] and [[immunological]] derivation. Hormone ([[ACTH]]) is a product of the HPA axis which stimulates secretion of [[corticosteroids]] from adrenals. In turn, corticosteroids modulate the immune response by virtue of their anti-inflammatory activity. On the other hand, [[catecholamines]], products of the [[sympathetic nervous system]] (SNS), regulate immune function by acting on specific beta-adrenergic receptors. Conversely, cytokines released by certain immune cells, upon stimulation, are able to cross the [[blood-brain-barrier]], thus modulating nervous functions (e.g., thermoregulation, sleep, and appetite). However, cytokines are locally produced in the brain, especially in the [[hypothalamus]], thus contributing to the development of appetite, thermoregulation, sleep and behavioural effects. In addition infections/pathogens and/or their products, the so-called stressors are able to activate both HPA axis and SNS, thus influencing immune responses. <ref name="pmid16029148">{{cite journal |author=Covelli V, Passeri ME, Leogrande D, Jirillo E, Amati L |title=Drug targets in stress-related disorders |journal=Curr. Med. Chem. |volume=12 |issue=15 |pages=1801–9 |year=2005 |pmid=16029148 | doi = 10.2174/0929867054367202 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
==Hypotheses==
{{Main|ME/CFS hypotheses}}
The  [[etiology]] (causation) of CFS is unknown, and many causes have been proposed. The etiology may be different for subgroups of patients, and may result in a common clinical outcome.<ref name="CDC Basic Overview">{{cite web | last = | first = | authorlink = | coauthors = | title = CFS Toolkit for Health Care Professionals: Basic CFS Overview | work = | publisher = U.S. Department of Health and Human Services, Centers for Disease Control and Prevention | date = | url = http://www.cdc.gov/cfs/pdf/Basic_Overview.pdf | format = PDF file, 31 KB | doi = | accessdate = 2008-03-19}}</ref> Some plausible hypotheses are as follows. (1) CFS is often associated with [[viral infection]]. (2) Anomalies of the [[HPA axis]] are often observed in CFS, but it is not clear if they are a cause or consequence of the disorder. (3) [[Immune dysfunction]] is also found in CFS studies, and hypothesized as the cause of CFS. (4) In the psychiatric and [[psychosocial]] model, some researchers hypothesize cognitive and behavioral factors are involved in the persistence of fatigue and illness behavior.<ref name="pmid9859853">{{cite journal |author=Vercoulen JH, Swanink CM, Galama JM, ''et al'' |title=The persistence of fatigue in chronic fatigue syndrome and multiple sclerosis: development of a model |journal=J Psychosom Res |volume=45 |issue=6 |pages=507–17 |year=1998 |pmid=9859853| doi = 10.1016/S0022-3999(98)00023-3 <!--Retrieved from CrossRef by DOI bot-->}}</ref> Other hypotheses for the causes of CFS are (5) [[Oxidative stress]] and (6) [[genetic predisposition]].<ref name="pmid17853290">{{cite journal |author=Sanders P, Korf J |title=Neuroaetiology of chronic fatigue syndrome: An overview |journal=[[World J Biol Psychiatry]] |volume= |issue= |pages=1–7 |year=2007 |pmid=17853290 |doi=10.1080/15622970701310971 |url=http://www.informaworld.com/openurl?genre=article&doi=10.1080/15622970701310971&magic=pubmed |issn= |unused_data=||1B69BA326FFE69C3F0A8F227DF8201D0}}</ref>
==Definitions, Guidelines, and Summaries==
{{Main|ME/CFS descriptions}}
In 1938, Gilliam reported an epidemic of the illness giving a detailed description that added up to a twenty-point definition. His report came to be recognized as the first useful description of ME, but official acknowledgment of its existence was delayed by concerned US authorities for four years.<ref name="isbn0-9695662-0-4">{{cite book |author=Byron M. Hyde |title=The Clinical and scientific basis of myalgic encephalomyelitis/chronic fatigue syndrome |publisher=Nightingale Research Foundation |location=Ogdensburg, N.Y |year=1992 |pages=  |isbn=0-9695662-0-4 |oclc= |doi=}}</ref>
Competing definitions, guidelines, and summary descriptions have accrued since then. Among them, some of the most notable are
* The Ramsay definition (1986) <ref name="Ramsay86">Ramsay MA (1986), "Postviral Fatigue Syndrome. The saga of Royal Free disease", Londen, ISBN 0-906923-96-4</ref>
* The Holmes ''et al'' (1988) scoring system,<ref name=Holmes1988>{{cite journal | author = Holmes G, Kaplan J, Gantz N, Komaroff A, Schonberger L, Straus S, Jones J, Dubois R, Cunningham-Rundles C, Pahwa S | title = Chronic fatigue syndrome: a working case definition, | journal = Ann Intern Med | volume = 108 | issue = 3 | pages = 387–9 | year = 1988 | pmid = 2829679}} [http://www.medicineau.net.au/clinical/medicine/CFS.html#holmes Details]</ref> sometimes called "CDC 1988"
* The Oxford criteria (1991)<ref name="oxford">{{cite journal | author = Sharpe M, Archard L, Banatvala J, Borysiewicz L, Clare A, David A, Edwards R, Hawton K, Lambert H, Lane R | title = A report--chronic fatigue syndrome: guidelines for research | journal = J R Soc Med | volume = 84 | issue = 2 | pages = 118–21 | year = 1991 | pmid= 1999813}} {{PMC|1293107}} Synopsis by {{GPnotebook|-476446699}})</ref>
* The "Fukada" CDC definition (1994),<ref name="CDC1994">{{cite journal | author = Fukuda K, Straus S, Hickie I, Sharpe M, Dobbins J, Komaroff A | title = The chronic fatigue syndrome: a comprehensive approach to its definition and study. International Chronic Fatigue Syndrome Study Group. | journal = Ann Intern Med | volume = 121 | issue = 12 | pages = 953–9 | year = 1994 | pmid=7978722|url=http://www.annals.org/cgi/content/full/121/12/953}}</ref> or "CDC 1994"
* The Carruthers ''et al'' (2003) Canadian Case definition for ME/CFS<ref name="carr">{{cite journal | author = Carruthers BM, Jain AK, De Meirleir KL, Peterson DL, Klimas MD, Lerner AM, Bested AC, Flor-Henry P, Joshi P, Powles ACP, Sherkey JA, van de Sande MI | title = Myalgic encephalomyalitis/chronic fatigue syndrome: Clinical working definition, diagnostic and treatment protocols | journal = Journal of Chronic Fatigue Syndrome | volume = 11 | issue = 1 | pages = 7–36 | year = 2003 | url = http://www.cfids-cab.org/MESA/me_overview.pdf | doi = 10.1300/J092v11n01_02}}</ref>
* The NICE (UK) 2007 criteria, a multidisciplinary clinical practice guideline published in 2007 by the UK's [[National Institute for Health and Clinical Excellence]] (NICE)<ref name=NICECG53>National Institute for Health and Clinical Excellence. ''Guideline 53: Chronic fatigue syndrome/myalgic encephalomyelitis (or encephalopathy)''. London, 2007. ISBN 1846294533. [http://guidance.nice.org.uk/CG53 NICE CG53 page].</ref>
[[Case definition]]s in CFS have largely been established to define patients for research study purposes, and have certain limitations when used for general practitioner purposes. Several studies have found that using different case definitions ( eg broad vs conservative<ref>{{cite journal | author = Jason LA, Corradi K, Torres-Harding S, Taylor RR, King C | title = Chronic fatigue syndrome: the need for subtypes. | journal = Neuropsychol Rev | volume = 15 | issue = 1 | pages = 29–58 | year = 2005 | pmid = 15929497 | doi = 10.1007/s11065-005-3588-2 <!--Retrieved from CrossRef by DOI bot-->}}</ref> ) has major influence on the types of patients selected and have also supported the distinction between specific subgroups of CFS to be identified and/or for the case definition to be further clarified with emphasis on using empirical studies: An international CFS study group for the CDC found in 2003 that ambiguities in the CDC 1994 CFS research case definition contribute to inconsistent case identification.<ref>{{cite journal | author = Reeves WC, Lloyd A, Vernon SD, Klimas N, Jason LA, Bleijenberg G, Evengard B, White PD, Nisenbaum R, Unger ER | title = Identification of ambiguities in the 1994 chronic fatigue syndrome research case definition and recommendations for resolution. | journal = BMC Health Serv Res | volume = 3 | issue = 1 | pages = 25 | year = 2003 | pmid = 14702202 | doi =  10.1186/1472-6963-3-25}}</ref> 
At this time, there is no accepted conclusive test or series of tests for ME/CFS.  According to the [[CDC]], the main purpose of performing diagnostic tests of any sort at this point in time, is to rule out other causes for fatigue and other symptoms of CFS.<ref name="CDC1994"/>  A review published in 2006 found that the accurate diagnosis of CFS is low<ref>{{cite journal | author = Maoz D, Shoenfeld Y | title = Chronic fatigue syndrome | journal = Harefuah | volume = 145 | issue = 4 | pages = 272–5, 319, 318 | year = 2006 | pmid = 16642629}}</ref>
[[Clinical practice guidelines]], with the aim of improving diagnosis, several countries have now produced these, which are generally based on case descriptions but these documents have the aim of guiding decisions and criteria regarding diagnosis, management, and treatment. Modern medical guidelines are based on an examination of current evidence within the paradigm of evidence-based medicine and they usually include summarized consensus statements. Guidelines are usually produced at national or international levels by medical associations or governmental bodies.
==Therapies==
{{Main|ME/CFS therapies}}
Improvement may occur with medical care and additional therapies of pacing,  [[cognitive behavioral therapy]] (CBT) and [[physical therapy|graded exercise therapy]] (GET). The latter two therapies have been found to be efficacious in small trials, but patient organisations surveys have reported adverse effects.<ref name="pmid17397525">{{cite journal |author=White PD, Sharpe MC, Chalder T, DeCesare JC, Walwyn R |title=Protocol for the PACE trial: a randomised controlled trial of adaptive pacing, cognitive behaviour therapy, and graded exercise, as supplements to standardised specialist medical care versus standardised specialist medical care alone for patients with the chronic fatigue syndrome/myalgic encephalomyelitis or encephalopathy |journal=[[BMC Neurol]] |volume=7 |issue= |pages=6 |year=2007 |pmid=17397525 |doi=10.1186/1471-2377-7-6 |url=http://www.biomedcentral.com/1471-2377/7/6 |issn=}}</ref>  Interventions involving [[rehabilitation]] therapies have been shown to be at least partially effective in some people with CFS.  <ref name="cbt_systematic_review">[{{cite journal |author=Chambers D, Bagnall AM, Hempel S, Forbes C |title=Interventions for the treatment, management and rehabilitation of patients with chronic fatigue syndrome/myalgic encephalomyelitis: an updated systematic review |journal=Journal of the Royal Society of Medicine |volume=99 |issue=10 |pages=506–20 |year=2006 |pmid=17021301 |doi=10.1258/jrsm.99.10.506}}</ref><ref name="pmid18042608">{{cite journal |author=Van Houdenhove B, Verheyen L, Pardaens K, Luyten P, Van Wambeke P |title=Rehabilitation of decreased motor performance in patients with chronic fatigue syndrome: should we treat low effort capacity or reduced effort tolerance? |journal=[[Clin Rehabil]] |volume=21 |issue=12 |pages=1121–42 |year=2007 |pmid=18042608 |doi=10.1177/0269215507080769 |url=http://cre.sagepub.com/cgi/pmidlookup?view=long&pmid=18042608 |issn=}}</ref><ref name="pmid17984153">{{cite journal |author=van Weering M, Vollenbroek-Hutten MM, Kotte EM, Hermens HJ |title=Daily physical activities of patients with chronic pain or fatigue versus asymptomatic controls. A systematic review |journal=[[Clin Rehabil]] |volume=21 |issue=11 |pages=1007–23 |year=2007 |pmid=17984153 |doi=10.1177/0269215507078331 |url=http://cre.sagepub.com/cgi/pmidlookup?view=long&pmid=17984153 |issn=}}</ref><ref name="pmid17467103">{{cite journal |author=Maquet D, Demoulin C, Croisier JL, Crielaard JM |title=Benefits of physical training in fibromyalgia and related syndromes |journal=[[Ann Readapt Med Phys]] |volume=50 |issue=6 |pages=363–8, 356–62 |year=2007 |pmid=17467103 |doi=10.1016/j.annrmp.2007.03.021 |url=http://linkinghub.elsevier.com/retrieve/pii/S0168-6054(07)00092-X |issn=}}</ref>
Some therapies recommended by different sources include:
*[[Adaptive pacing]]<ref name="pmid17397525">{{cite journal |author=White PD, Sharpe MC, Chalder T, DeCesare JC, Walwyn R |title=Protocol for the PACE trial: a randomised controlled trial of adaptive pacing, cognitive behaviour therapy, and graded exercise, as supplements to standardised specialist medical care versus standardised specialist medical care alone for patients with the chronic fatigue syndrome/myalgic encephalomyelitis or encephalopathy |journal=[[BMC Neurol]] |volume=7 |issue= |pages=6 |year=2007 |pmid=17397525 |doi=10.1186/1471-2377-7-6 |url=http://www.biomedcentral.com/1471-2377/7/6 |issn=}}</ref>
*[[Cognitive behavior therapy]]<ref name="pmid17521842">{{cite journal |author=Scheeres K, Wensing M, Mes C, Bleijenberg G |title=The impact of informational interventions about cognitive behavioral therapy for chronic fatigue syndrome on GPs referral behavior |journal=[[Patient Educ Couns]] |volume=68 |issue=1 |pages=29–32 |year=2007 |pmid=17521842 |doi=10.1016/j.pec.2007.04.002 |url=http://linkinghub.elsevier.com/retrieve/pii/S0738-3991(07)00143-7 |issn=}}</ref>
*[[Envelope theory]]<ref name="pmid10205371">{{cite journal |author=Jason LA, Melrose H, Lerman A, ''et al'' |title=Managing chronic fatigue syndrome: overview and case study |journal=[[AAOHN J]] |volume=47 |issue=1 |pages=17–21 |year=1999 |pmid=10205371 |doi= |issn=}}</ref>
*[[Graded exercise therapy]]<ref name="pmid18382818">{{cite journal |author=Nijs J, Paul L, Wallman K |title=Chronic fatigue syndrome: An approach combining self-management with graded exercise to avoid exacerbations |journal=[[J Rehabil Med]] |volume=40 |issue=4 |pages=241–7 |year=2008 |pmid=18382818 |doi=10.2340/16501977-0185 |url=http://jrm.medicaljournals.se/article/full/10.2340/16501977-0185 |issn=}}</ref>
*[[Chair Yoga|Yoga]]<ref name="pmid15889950">{{cite journal |author=Bentler SE, Hartz AJ, Kuhn EM |title=Prospective observational study of treatments for unexplained chronic fatigue |journal=[[J Clin Psychiatry]] |volume=66 |issue=5 |pages=625–32 |year=2005 |pmid=15889950 |doi= |url=http://article.psychiatrist.com/?ContentType=START&ID=10001314 |issn=}}</ref>
*[[Physiotherapy]]<ref name="pmid16781183">{{cite journal |author=Nijs J, Meeus M, De Meirleir K |title=Chronic musculoskeletal pain in chronic fatigue syndrome: recent developments and therapeutic implications |journal=[[Man Ther]] |volume=11 |issue=3 |pages=187–91 |year=2006 |pmid=16781183 |doi=10.1016/j.math.2006.03.008 |url=http://linkinghub.elsevier.com/retrieve/pii/S1356-689X(06)00055-5 |issn=}}</ref>
==Treatment==
{{Main|ME/CFS treatments}}
Many patients do not fully recover from CFS, even with treatment.<ref>{{cite journal | author = Rimes KA, Chalder T. | title = Treatments for chronic fatigue syndrome. | journal = Occupational Medicine | volume = 55 | issue = 1 | pages = 32–39 | year = 2005 | pmid = 15699088 | doi = 10.1093/occmed/kqi015 <!--Retrieved from CrossRef by DOI bot-->}}</ref> Some management strategies are suggested to reduce the consequences of having CFS. [[Medications]], other [[medical treatment]]s, [[complementary and alternative medicine]] are considered. A systematic review has shown that CFS patients are less susceptible to placebo effects than predicted, and have a low placebo response compared to patients with other diseases.<ref>{{cite journal | author = Cho HJ, Hotopf M, Wessely S | title = The placebo response in the treatment of chronic fatigue syndrome: a systematic review and meta-analysis. | journal = Psychosom Med | volume = 67 | issue = 2 | pages = 301–13 | year = 2005 | pmid = 15784798 | doi = 10.1097/01.psy.0000156969.76986.e0 <!--Retrieved from CrossRef by DOI bot-->}}</ref> CFS is associated with chemical sensitivity,<ref name="pmid11020095">{{cite journal |author=Jason LA, Taylor RR, Kennedy CL |title=Chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities in a community-based sample of persons with chronic fatigue syndrome-like symptoms |journal=Psychosom Med |volume=62 |issue=5 |pages=655–63 |year=2000 |pmid=11020095 |doi=}}</ref> <ref name="pmid12000024">{{cite journal |author=Clauw DJ |title=Potential mechanisms in chemical intolerance and related conditions |journal=Ann. N. Y. Acad. Sci. |volume=933 |issue= |pages=235–53 |year=2001 |pmid=12000024 |doi=}}</ref> and some patients often  respond to a fraction of a therapeutic dose that is normal for other conditions.<ref name="pmid8827194">{{cite journal |author=Gruber AJ, Hudson JI, Pope HG |title=The management of treatment-resistant depression in disorders on the interface of psychiatry and medicine. Fibromyalgia, chronic fatigue syndrome, migraine, irritable bowel syndrome, atypical facial pain, and premenstrual dysphoric disorder |journal=Psychiatr. Clin. North Am. |volume=19 |issue=2 |pages=351–69 |year=1996 |pmid=8827194| doi = 10.1016/S0193-953X(05)70292-6 <!--Retrieved from CrossRef by DOI bot-->}}</ref><ref>{{cite web | last = National Center for Infectious Diseases | title = Treatment of Patients with Chronic Fatigue Syndrome | publisher = Centers for Disease Control and Prevention | date = 2005-05-11 | url = http://www.cdc.gov/ncidod/diseases/cfs/treat.htm | format = htm | doi = | accessdate = 2008-04-07}}</ref>
A 2005 review in the journal ''Curr Med Chem.'' concluded, “it seems that major drug targets in stress-related disorders are immune cells in terms of inhibition of proinflammatory cytokines and modulation of Th (cytokine pattern) responses”. In CFS, in a series of recent therapeutic trials several immunomodulating agents have been used, such as staphypan Berna, lactic acid bacteria, kuibitang and intravenous immunoglobulin. In particular, according to recent evidences, antidepressants seem to exert beneficial effects in augmenting NK cell activity in depressed patients. <ref name="pmid16029148">{{cite journal |author=Covelli V, Passeri ME, Leogrande D, Jirillo E, Amati L |title=Drug targets in stress-related disorders |journal=Curr. Med. Chem. |volume=12 |issue=15 |pages=1801–9 |year=2005 |pmid=16029148 | doi = 10.2174/0929867054367202 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
==Prognosis==
===Recovery===
A systematic review of 14 studies of the outcome of untreated people with CFS found that "the median full recovery rate was 5% (range 0–31%) and the median proportion of patients who improved during follow-up was 39.5% (range 8–63%). Return to work at follow-up ranged from 8 to 30% in the three studies that considered this outcome." .... "In five studies, a worsening of symptoms during the period of follow-up was reported in between 5 and 20% of patients."<ref name=Cairns2005>{{cite journal |author=Cairns R, Hotopf M |title=A systematic review describing the prognosis of chronic fatigue syndrome |journal=Occupational medicine (Oxford, England) |volume=55 |issue=1 |pages=20–31 |year=2005 |pmid=15699087 |doi=10.1093/occmed/kqi013}}</ref> It is not known whether any patients truly "recover" entirely from the illness, or achieve remission from a relapsing, remitting illness. Few untreated patients report a total "cure".
===Deaths===
CFS is unlikely to increase the risk of an early death. A systematic review of 14 studies of the outcome of CFS reported 8 deaths, but none were considered directly attributable to CFS.<ref name=Cairns2005/> To date there have been two studies directly addressing life expectancy in CFS. In a preliminary 2006 study of CFS self-help group members, it was reported that CFS patients were likely to die at a younger than average age for cancer, heart failure, and suicide.<ref>{{cite journal |author=Jason LA, Corradi K, Gress S, Williams S, Torres-Harding S |title=Causes of death among patients with chronic fatigue syndrome |journal=Health care for women international |volume=27 |issue=7 |pages=615–26 |year=2006 |pmid=16844674 |doi=10.1080/07399330600803766}}</ref> However, a much larger study of 641 CDC criteria diagnosed patients with CFS, who were followed up for a mean of 9 years, showed no excess risk of dying from any cause.<ref>{{cite journal |author=Smith WR, Noonan C, Buchwald D |title=Mortality in a cohort of chronically fatigued patients |journal=Psychological medicine |volume=36 |issue=9 |pages=1301–6 |year=2006 |pmid=16893495 |doi=10.1017/S0033291706007975}}</ref>
People diagnosed with CFS ''may'' die, as in the case in the [[UK]] of [[Sophia Mirza]], where the coroner recorded a verdict of "[[acute renal failure|Acute anuric renal failure]] due to dehydration arising as a result of CFS." According to Sophia's mother, Sophia became intolerant to water and managed only 4 fluid ounces per day.<ref>[http://www.25megroup.org/Campaigning/Awareness%202006/Sophia's%20story/sophia's%20story%2006.htm Sophia's story]</ref> The pathologist said, "ME describes inflammation of the spinal cord and muscles. My work supports the inflammation theory...The changes of [[dorsal root]] ganglionitis seen in 75% of Sophia's [[spinal cord]] were very similar to that seen during active infection by herpes viruses." This was seen as a form of recognition by the ME community.<ref>{{cite news | title=Fatigue syndrome ruling welcomed |url=http://news.bbc.co.uk/1/hi/uk/5112050.stm |format= |work= |publisher= |id= |pages= |page= |date=[[2006-06-23]] |accessdate = 2007-09-03 |language=English}}</ref> Previous cases have listed CFS as the cause of death in the US and Australia<ref>[http://www.meactionuk.org.uk/Inquest_Implications.htm Inquest Implications: Marshall E, Williams, M, June 2006]</ref>
==Epidemiology==
Due to problems with the definition of CFS, estimates of its [[prevalence]] vary widely. Studies in the United States have previously found between 75 and 420 cases of CFS for every 100,000 adults. The CDC states that more than 1 million Americans have CFS and approximately 80% of the cases are undiagnosed.<ref name="CDCBasic">{{cite web | title = Chronic Fatigue Syndrome Basic Facts | publisher = Centers for Disease Control and Prevention | date = May 9, 2006 | url = http://www.cdc.gov/cfs/cfsbasicfacts.htm | format = htm | accessdate = 2008-02-07}}</ref> All ethnic and racial groups appear susceptible to the illness, and lower income groups are slightly more likely to develop CFS.<ref name="CDCRisk"/> More women than men get CFS &mdash; between 60 and 85% of cases are women; however, there is some indication that the prevalence among men is underreported. The illness is reported to occur more frequently in people between the ages of 40 and 59. Blood relatives of people who have CFS appear to be more predisposed.<ref name="CDCRisk">{{cite web | title = Chronic Fatigue Syndrome Who's at risk? | publisher = Centers for Disease Control and Prevention | date = March 10, 2006 | url = http://www.cdc.gov/cfs/cfscausesHCP.htm | format = htm | accessdate = 2008-02-07}}</ref><ref>{{cite journal | author = Walsh CM, Zainal NZ, Middleton SJ, Paykel ES | title = A family history study of chronic fatigue syndrome. | journal = Psychiatr Genet | volume = 11 | issue = 3 | pages = 123–8 | year = 2001 | pmid = 11702053 | doi = 10.1097/00041444-200109000-00003 <!--Retrieved from CrossRef by DOI bot-->}}</ref> However, CFS does not appear directly contagious; caretakers, partners and others in close contact with persons with CFS for years do not develop CFS any more frequently (excluding relatives, as earlier).
Epidemiological research on children and adolescents has received minimal focus according to a 2006 research review. Among minors, prevalence appears to be lower than for adults and various studies have found a range of 50-80% of the cases occur in girls. The authors hypothesize the differences in estimates of ME/CFS among pediatric studies may result because of the lack of a reliable pediatric case definition.<ref name="DOI : 10.1300/J092v13n02_01"/>
CFS generally occurs in [[Endemic (epidemiology)|endemic]] cases. In addition, over 50 instances have been documented, such as the [[Royal Free Hospital]] incident, where [[epidemic]] clusters were reported.<ref name="Ramsay86">Ramsay MA (1986), "Postviral Fatigue Syndrome. The saga of Royal Free disease", Londen, ISBN 0-906923-96-4</ref><ref name="isbn0-9695662-0-4"/> In these instances, significant numbers of people came down with illnesses described as ME or CFS simultaneously, confined to a local area or even a single building. An infectious origin for these clusters was considered highly likely due to:
* transference by inoculation to monkeys which developed symptomology and on post-mortem demonstrated neurological, vascular and cardiac damage (Fellow and Miles, 1955).
* human post-mortems or scans demonstrating abnormalities consistent with chronic infection (Wallis 1957, Schwartz et al 1994)
* serologic evidence of Iceland Disease blocking spread of polio type I spreading northwards (Sigurdsson et al, 1958). 
* the pattern of acute onset with pharyngitis, mild fever, muscular pain, neck stiff­ness, cervical lymphadenopathy, gastroenteric symptoms, diffuse CNS involvement and photosensitivity were consistent with viral infection with an observed incubation period of 5-7 days.  The biphasic clinical picture echoes pathogenesis through the pharynx, spreading through the reticuloendothelial barrier, then the CNS, resulting in morphological changes in mature lymphocytes and antibody creation. (Acheson, Ramsay, Richardson, Crowley, Dillon et al)
* A predilection for residential communities and most outbreaks occurring in summer (Acheson)
* The isolation of the non-polio enterovirus ECHO-9 in patients (Lyle, Annals of Internal Medicine 1959; 51: 248-269)
* psychiatric disease was a widely regarded exclusion for M.E. diagnosis (e.g. Acheson) and positive criteria for hysteria were absent (Gosling, Mayne, 1970).
* At the 1978 RSM Symposium, new evidence was presented of increased anti-complementary activity and the ability of lymphocytes to proliferate and survive in vitro for up to 19 weeks. (Compston 1978).
Since most current definitions of CFS exclude such findings and signs, it is disputed whether they refer to a differential diagnosis (but see below).
According to the CDC, CFS itself is not contagious.<ref name="CDCDemographics">{{cite web | title = Chronic Fatigue Syndrome Demographics | publisher = Centers for Disease Control and Prevention | date = May 11, 2005 | url = http://www.cdc.gov/ncidod/diseases/cfs/about/demographics.htm| format = htm | accessdate = 2008-02-07}}</ref>
===Disease associations===
Some diseases show a considerable overlap with CFS. According to an article in ''American Family Physician'' in 2002, [[Multiple Sclerosis]], [[Thyroid|Thyroid disorders]], [[anemia]], and [[diabetes]] are but a few of the diseases that must be ruled out if the patient presents with appropriate symptoms.<ref name="CDC1994"/><ref name="CFSeval">{{cite journal | author = Craig, T and  Kakumanu S| title = Chronic fatigue syndrome: evaluation and treatment | journal = Am Fam Physician. | volume = 65 |issue = 6 |pages = 1083–90 |year = Mar 2002 |url = http://www.aafp.org/afp/20020315/1083.html | pmid = 11925084}}</ref>
People with [[fibromyalgia]] (FM, or Fibromyalgia Syndrome, FMS) have muscle pain and sleep disturbances. Fatigue and muscle pain occurs frequently in the initial phase of various hereditary muscle disorders and in several autoimmune, endocrine and metabolic syndromes; and are frequently labelled as CFS or fibromyalgia in the absence of obvious biochemical/metabolic abnormalities and neurological symptoms.<ref>{{cite journal | author = van de Glind G, de Vries M, Rodenburg R, Hol F, Smeitink J, Morava E | title = Resting muscle pain as the first clinical symptom in children carrying the MTTK A8344G mutation. | journal = Eur J Paediatr Neurol | year = 2007 | pmid = 17293137}}</ref> Those with [[multiple chemical sensitivity]] (MCS) are sensitive to chemicals and have sleep disturbances. Many veterans with [[Gulf War syndrome]] (GWS) have symptoms almost identical to CFS.<ref>{{cite journal | author = Vojdani A, Thrasher J | title = Cellular and humoral immune abnormalities in Gulf War veterans. | journal = Environ Health Perspect | volume = 112|issue = 8|pages = 840–6|year = 2004|pmid = 15175170 | doi = 10.1289/ehp.6881}}</ref> One study found several parallels when relating the symptoms of [[Post-polio syndrome]] with CFS, and postulates a possible common pathophysiology for the illnesses.<ref name="polio">{{cite journal | author = Bruno RL, Creange SJ, Frick NM | title = Parallels between post-polio fatigue and chronic fatigue syndrome: a common pathophysiology? | journal = Am J Med. | volume = 105 |issue = 3A |pages = 66S–73S |year = 1998 |pmid = 9790485 | doi = 10.1016/S0002-9343(98)00161-2 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
Although post-Lyme syndrome and CFS share many features/symptoms, a study found that patients of the former experience more cognitive impairment and the patients of the latter experience more flu-like symptoms.<ref>{{cite journal | author = Gaudino EA, Coyle PK, Krupp LB | title = Post-Lyme syndrome and chronic fatigue syndrome. Neuropsychiatric similarities and differences. | journal = Arch Neurol | volume = 54 | issue = 11 | pages = 1372–6 | year = 1997 | pmid = 9362985}}</ref>
One review (2006) found that there was a lack of literature to establish the [[discriminant validity]] of undifferentiated [[somatoform disorder]] from CFS. The author stated that there is a need for proponents of chronic fatigue syndrome to distinguish it from undifferentiated somatoform disorder. The author also mentioned that the experience of fatigue as exclusively physical and not mental is captured by the definition of somatoform disorder but not CFS.<ref>{{cite journal | author = van Staden WC | title = Conceptual issues in undifferentiated somatoform disorder and chronic fatigue syndrome. | journal = Curr Opin Psychiatry | volume = 19 | issue = 6 | pages = 613–8 | year = 2006 | pmid = 17012941}}</ref> Hysterical diagnoses are not merely diagnoses of exclusion but require criteria to be met on the positive grounds of both primary and secondary gain.<ref>Jenkins R, Mowbray J, ed. Post-viral Fatigue Syndrome. 1991 John Wiley & Sons Ltd</ref>  Primary Depression can be excluded in the [[differential diagnosis]] due to the absence of [[anhedonia]] and [[la belle indifference]], the variability (lability) of mood, and the presence of sensory phenomena and somatic signs such as ataxia, myclonus and most importantly, exercise intolerance with paresis, malaise and general deterioration, which can in some cases become a comorbid situational depression.
===Co-morbidity===
Many CFS patients will also have, or appear to have, other medical problems or related diagnoses. Co-morbid [[fibromyalgia]] is common, although there are differences in pain complaints.<ref>{{cite journal | author =  Bradley LA, McKendree-Smith NL, Alarcon GS | title = Pain complaints in patients with fibromyalgia versus chronic fatigue syndrome. | journal = Curr Rev Pain | volume = 4 | issue = 2 | pages = 148–57 | year = 2000 | pmid = 10998728}}</ref> Fibromyalgia occurs in a large percentage of CFS patients between onset and the second year, and some researchers suggest fibromyalgia and CFS are related.<ref>{{cite journal | author = Friedberg F, Jason LA | title = Chronic fatigue syndrome and fibromyalgia: clinical assessment and treatment. | journal = J Clin Psychol. | volume = 57 | issue = 4 | pages = 433–55 | year = 2001 | pmid = 11255201  | doi = 10.1002/jclp.1040}}</ref> Similarly, [[multiple chemical sensitivity]] (MCS) is reported by many CFS patients, and it is speculated that these similar conditions may be related by some underlying mechanism, such as elevated nitric oxide/peroxynitrite.<ref>{{cite journal | author = Pall ML, Satterlee JD | title = Elevated nitric oxide/peroxynitrite mechanism for the common etiology of multiple chemical sensitivity, chronic fatigue syndrome, and posttraumatic stress disorder. | journal = Ann N Y Acad Sci | volume = 933 | pages = 323–9 | year = 2001 | pmid = 12000033}}</ref> As previously mentioned, many CFS sufferers also experience symptoms of [[irritable bowel syndrome]], [[temporomandibular joint]] pain, [[headache]] including [[migraine]]s, and other forms of [[myalgia]]. [[Clinical depression]] and [[anxiety]] are also commonly co-morbid. Compared with the non-fatigued population, male CFS patients are more likely to experience [[Prostatitis#Category III: CP/CPPS, pelvic myoneuropathy|chronic pelvic pain syndrome (CP/CPPS)]], and female CFS patients are also more likely to experience [[chronic pelvic pain]].<ref>{{cite journal | author = Aaron LA, Herrell R, Ashton S, Belcourt M, Schmaling K, Goldberg J, Buchwald D | title = Comorbid clinical conditions in chronic fatigue: a co-twin control study. | journal = J Gen Intern Med | volume = 16 | issue = 1 | pages = 24–31 | year = 2001 | pmid = 11251747 | url = http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=11251747 | doi = 10.1111/j.1525-1497.2001.03419.x <!--Retrieved from CrossRef by DOI bot-->}}</ref> CFS is significantly more common in women with [[endometriosis]] compared with women in the general USA population.<ref>{{cite journal | author = Sinaii N, Cleary SD, Ballweg ML, Nieman LK, Stratton P | title = High rates of autoimmune and endocrine disorders, fibromyalgia, chronic fatigue syndrome and atopic diseases among women with endometriosis: a survey analysis. | journal = Hum Reprod | volume = 17 | issue = 10 | pages = 2715–24 | year = 2002 | pmid = 12351553 | doi = 10.1093/humrep/17.10.2715 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
===Social issues===
Many patients find that a chronic fatigue syndrome diagnosis carries a considerable stigma, and has frequently been viewed as malingering, hypochondriac, phobic, "wanting attention" or "yuppie flu". As there is no objective test for the condition at this time, it has been argued that it is easy to invent or feign CFS-like symptoms for financial, social, or emotional benefits.<ref name="isbn: 1572301732">{{cite book | last = Rogers | first = Richard | title = Clinical Assessment of Malingering and Deception, Second Edition | publisher = Guilford Press | date = 1997 | location = New York, London | pages = pg 40 of 525 | url = http://books.google.com/books?id=YZ6uK4Cjd_MC&printsec=frontcover&dq=somatoform+deception+chronic+fatigue+syndrome | page = 40 | isbn = 1572301732}}</ref><ref name="isbn: 0773529942">{{cite book | last = Malleson | first = Andrew | title = Whiplash and Other Useful Illnesses | publisher = McGill-Queen's Press | date = 2005 | location = Quebec | pages = pg 59 of 544 | url = http://books.google.com/books?id=naDghccZhEwC&vq=Whiplash+and+Other+Useful+Illnesses | isbn = 0773529942}}</ref> CFS sufferers argue in turn that the perceived "benefits" are hardly as generous as some may believe, and that CFS patients would greatly prefer to be healthy and independent. A study found that CFS patients endure a heavy psychosocial burden.<ref name="PMID_12097786">{{cite journal | author = Van Houdenhove B, Neerinckx E, Onghena P, Vingerhoets A, Lysens R, Vertommen H | title = Daily hassles reported by chronic fatigue syndrome and fibromyalgia patients in tertiary care: a controlled quantitative and qualitative study. | journal = Psychother Psychosom | volume = 71 | issue = 4 | pages = 207–13 | year = 2002 | pmid = 12097786 | doi = 10.1159/000063646}}</ref>  2,338 respondents of a survey by a UK patient organization highlights that those with the worst symptoms often receive the least support from health and social services.<ref name="Neglected">[http://www.afme.org.uk/res/img/resources/Severely%20Neglected.pdf Action for M.E. in the UK, Severely Neglected: Membership Survey] London: Action for M.E.; 2001</ref>  A study found that CFS patients receive worse social support than disease-free cancer patients or healthy controls, which may perpetuate fatigue severity and functional impairment in CFS.<ref name="nosupport"/> A survey by the Thymes Trust found that children with CFS often state that they struggle for recognition of their needs and/or they feel bullied by medical and educational professionals.<ref name="colby_special">{{cite journal | author = Colby J | title = Special problems of children with myalgic encephalomyelitis/chronic fatigue syndrome and the enteroviral link. | journal = J Clin Pathol | volume = 60 | issue = 2 | pages = 125–8 | year = 2007 | id = 16935964 | doi = 10.1136/jcp.2006.042606 | pmid = 16935964}}</ref> The ambiguity of the status of CFS as a medical condition may cause higher perceived stigma.<ref>{{cite journal | author = Looper KJ, Kirmayer LJ | title = Perceived stigma in functional somatic syndromes and comparable medical conditions. | journal = J Psychosom Res | volume = 57 | issue = 4 | pages = 373–8 | year = 2004 | pmid = 15518673}}</ref> A study suggests that while there are no gender differences in CFS symptoms, men and women have different perceptions of their illness and are treated differently by the medical profession.<ref>{{cite journal | author = Clarke JN | title = Chronic fatigue syndrome: gender differences in the search for legitimacy. | journal = Aust N Z J Ment Health Nurs | volume = 8 | issue = 4 | pages = 123–33 | year = 1999 | pmid = 10855087 | doi = 10.1046/j.1440-0979.1999.00145.x}}</ref> Anxiety and depression often result from the emotional, social and financial crises caused by CFS. While few studies have been made, it is believed that CFS patients are at a high risk of suicide.<ref>{{cite journal | author = Jason L, Corradi K, Gress S, Williams S, Torres-Harding S | title = Causes of death among patients with chronic fatigue syndrome. | journal = Health Care Women Int | volume = 27 | issue = 7 | pages = 615–26 | year = 2006 | pmid = 16844674 | doi = 10.1080/07399330600803766 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
A lack of information and awareness has led to many patients to feel stigmatized.<ref>Green J, Romei J, Natelson BH (1999) Stigma and Chronic Fatigue Syndrome Journal of Chronic Fatigue Syndrome, Vol. 5, No. 2, 1999</ref> CFS patients may not receive total medical and social acceptance and they state that some people trivialise the illness.<ref name="nosupport">{{cite journal | author = Prins JB, Bos E, Huibers MJ, Servaes P, van der Werf SP, van der Meer JW, Bleijenberg G | title = Social support and the persistence of complaints in chronic fatigue syndrome. | journal = Psychother Psychosom | volume = 73 | issue = 3 | pages = 174–82 | year = 2004 | pmid = 15031590 | doi = 10.1159/000076455 <!--Retrieved from CrossRef by DOI bot-->}}</ref> <ref name="hooper_pathol_06">{{cite journal | author = Hooper M | title = Myalgic Encephalomyelitis (ME): a review with emphasis on key findings in biomedical research. | journal = J Clin Pathol | year = 2006 | doi = 10.1136/jcp.2006.042408 | volume = 60 | pages = 466 | pmid = 16935967}}[http://jcp.bmj.com/cgi/content/abstract/jcp.2006.042408v2]</ref> When the illness is coupled with unaccommodating family, friends, colleagues, often due to [[social stigma|stigma]], and social repercussions such as financial needs, housing problems, the struggle to obtain disability benefits or insurance, discrimination and misconception within the care sector, it can put demands on the sufferer exceeding their safe capabilities. Many sufferers say that they need to do things for themselves during the time in which they feel better as there is no-one to delegate these tasks to.<ref name="nosupport"/>
==History==
{{Main|ME/CFS history}}
Attempts to describe conditions similar to ME/CFS date back to at least the [[17th Century]].<ref>Sydenham T, "The Works of Thomas Sydenham, M.D.", (translated from the Latin edition of Greenhill WA by Latham RG), Vol. 1, Londen, Sydenham Society, 1847</ref><ref name="isbn0-9695662-0-4">{{cite book |author=Byron M. Hyde |title=The Clinical and scientific basis of myalgic encephalomyelitis/chronic fatigue syndrome |publisher=Nightingale Research Foundation |location=Ogdensburg, N.Y |year=1992 |pages=  |isbn=0-9695662-0-4 |oclc= |doi=}}</ref>
A major outbreak in 1934 at the [[Los Angeles County Hospital]] infected all or most of its nurses and doctors.  It was referred to as ''Atypical Poliomyelitis'', and was generally believed to be a form of polio.<ref name="ISBN 078902196X_p6-7">{{cite book
|author=Roberto Patarca-Montero|title=Medical Etiology, Assessment, and Treatment of Chronic Fatigue and Malaise |publisher=Haworth Press
|location=|year=2004|pages=6-7|isbn=078902196X |oclc= |doi=}}</ref>
The outbreak that gave it one of its most common names, Myalgic Encephalomyelitis, occurred at London's [[Royal Free Hospital]] in 1955, inflicting mostly the hospital staff, and formed the basis of descriptions by Achenson, Ramsay, and others.<ref name="pmid13472002">{{cite journal |author= |title=AN OUTBREAK of encephalomyelitis in the Royal Free Hospital Group, London, in 1955 |journal=Br Med J |volume=2 |issue=5050 |pages=895–904 |year=1957 |pmid=13472002 |doi= |url=[http://books.google.com/books?id=QNqC7DUdJRsC&pg=PA7&lpg=PA7&dq=%22Los+Angeles+County+Hospital%22+%22atypical+poliomyelitis%22+1934&source=web&ots=YxwC9ReIvY&sig=5qOLM39lp3BE-qnKc0x6Xc41Fc8&hl=en]}}</ref>
Although early reports described epidemics, and by the 1950’s at least fourteen had occurred worldwide, (see [[ME/CFS outbreaks]]) of which seven of the fourteen occurred in staffs of hospitals. By the 1990's at least 50 similar clusters or epidemics have appeared in the medical literature. "It has always been known by investigators that these epidemics of ME/CFS tended merely to highlight the same disease activity in the general public in the epidemic area". Reports of cases were fairly stable through the 70’s. But since 1979 there has been an enormous but poorly documented increase in cases of ME/CFS. These increases compounded slowly until 1984 when an exponential increase occurred. The numbers did not drop afterwards as one might expect after an epidemic but have continued to rise in increasing number. <ref name="isbn0-9695662-0-4">{{cite book |author=Byron M. Hyde |title=The Clinical and scientific basis of myalgic encephalomyelitis/chronic fatigue syndrome |publisher=Nightingale Research Foundation |location=Ogdensburg, N.Y |year=1992 |pages=  |isbn=0-9695662-0-4 |oclc= |doi=}}</ref>
(Benign) Myalgic Encephalomyelitis was first classified into the [[ICD|International Classification of Diseases]] in 1969 under ''Diseases of the nervous system''.<ref name="ICD_8_ME">{{Citation | title = International Classification of Diseases | publisher = World Health Organization | year = 1969 | volume = I | edition = | pages = 158, (vol 2, pp. 173) | url = | doi = | id = | isbn = }}</ref>
The name Chronic Fatigue Syndrome has been attributed to the 1988 article, "Chronic fatigue syndrome: a working case definition", ([[ME/CFS descriptions#Holmes|Holmes definition]]). This research case definition was published after US [[Centers for Disease Control]] epidemiologists examined patients at the Lake Tahoe outbreak.<ref name="isbn0-19-263049-0">{{cite book |author=Sharpe, Michael; Frankie Campling |title=Chronic Fatigue Syndrome (CFS/ME): TheFacts |publisher=Oxford Press |location=Oxford |year=2000 |pages = 14,15 | url = http://books.google.com/books?id=_LqAIK616lgC&pg=PA14&lpg=PA14&dq=chronic+fatigue+syndrome+was+coined+in+1988+by+the+centers+for+disease+control&source=web&ots=ES1o1bhpI7&sig=wIR949lr8B6HdNF3lcMrx4fh77M&hl=en#PPA14,M1 |isbn=0-19-263049-0 |oclc= |doi=| accessdate = 2008-04-02}}</ref><ref name="isbn0801879426">{{cite book |author=Packard RM, Berkelman RL, Brown PJ, Frumkin H |title=Emerging Illnesses and Society |publisher=JHU Press
|location= |year= 2004 |pages = 156| url = http://books.google.com/books?id=EGNFPZrKIKMC&pg=PA156&dq=cdc+lake+tahoe+1988&ei=fOHyR5-eFabUswOt67TGCg&sig=5bBdvIlqxhkBzNUVnGHaQbnhUBM#PPA156,M1 |isbn=0801879426 |oclc= |doi=| accessdate = 2008-04-02}}</ref><ref name=Holmes1988>{{cite journal | author = Holmes G, Kaplan J, Gantz N, Komaroff A, Schonberger L, Straus S, Jones J, Dubois R, Cunningham-Rundles C, Pahwa S | title = Chronic fatigue syndrome: a working case definition. | journal = Ann Intern Med | volume = 108 | issue = 3 | pages = 387–9 | year = 1988 | pmid = 2829679}}</ref> 
In 2006 the CDC estimated there were more than 1 million cases of CFS in the US and commenced a public awareness program.<ref name="CDCBasic">{{cite web | title = Chronic Fatigue Syndrome Basic Facts | publisher = Centers for Disease Control and Prevention | date = May 9, 2006 | url = http://www.cdc.gov/cfs/cfsbasicfacts.htm | format = htm | accessdate = 2008-02-07}}</ref>
Since inception, the condition has been steeped in [[ME/CFS controversies|controversy]]. Despite continuous research and many [[ME/CFS pathophysiology|findings]], indicating also likely subsets of patients, the present state of study on this condition is fragmented and contentious.<ref name="pmid 10583715">{{cite journal |author= Evangard B, Schacterie R.S., Komaroff A. L. |title=Chronic fatigue syndrome: new insights and old ignorance |journal=Journal of Internal Medicine |volume=Nov;246 |issue=5 |pages=455–469 |year=1999 |pmid=10583715 | doi = 10.1046/j.1365-2796.1999.00513.x <!--Retrieved from URL by DOI bot-->|url= http://www.blackwell-synergy.com/doi/pdf/10.1046/j.1365-2796.1999.00513.x | accessdate = 2008-04-02}}</ref>
==Controversies==
{{Main|ME/CFS controversies}}
ME/CFS is an illness with a long history of controversies, which include:
====The name====
Competing terms to describe the condition(s) have been used over the years in different parts of the world (see [[ME/CFS nomenclatures]]). Many groups say the name Chronic Fatigue Syndrome is unsatisfactory and want it changed because it trivializes the illness.<ref name="Jason">{{cite journal|author=Jason LA, Taylor RR| year=2001|title= Measuring Attributions About Chronic Fatigue Syndrome|journal=J Chronic Fatigue Syndr| volume=8|issue=3/4 |pages=31–40 |url=http://www.cfids-cab.org/cfs-inform/Welcome/jason.taylor01.txt |format=TXT|doi= 10.1300/J092v08n03_04}}</ref>
According to studies conducted by Jason, the name Chronic Fatigue Syndrome may be taken less seriously than the name Myalgic Encephalopathy by medical trainees concerning important aspects of the condition.<ref name="pmid11928774">{{cite journal |author=Jason LA, Taylor RR, Plioplys S, Stepanek Z, Shlaes J |title=Evaluating attributions for an illness based upon the name: chronic fatigue syndrome, myalgic encephalopathy and Florence Nightingale disease |journal=Am J Community Psychol |volume=30 |issue=1 |pages=133–48 |year=2002 |pmid=11928774| doi = 10.1023/A:1014328319297 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
====The cause(s), diagnosis, and treatment  ====
For years, many professionals within the medical community did not recognize ME/CFS as a real condition, nor was there agreement on its prevalence.<ref name= "pmid1794092">{{cite journal | last = Wallace | first = PG. | title = Post-viral fatigue syndrome. Epidemiology: a critical review | journal = Br Med Bull. | volume = 47 | issue = 4 | pages = 942–951 | date = 1991 Oct. | pmid = 1794092}}</ref><ref name= "pmid9231495">{{cite journal | last = Mounstephen | first = A, | coauthors = Sharpe M.  | title = Chronic fatigue syndrome and occupational health | journal = Occup Med (Lond).  May;47(4):. | volume = 47 | issue = 4 | pages = 217–227 | date = 1997 May | pmid = 1794092  | doi = 10.1093/occmed/47.4.217}}</ref> There has been much disagreement over proposed cause(s), diagnosis, and treatment of the illness.<ref name= "pmid11446147">{{cite journal |author=Hooge J |title=Chronic fatigue syndrome: cause, controversy and care |journal=Br J Nurs |volume=1 |issue=9 |pages=440–1, 443, 445–6 |year=1992 |pmid=1446147 |doi=}}</ref><ref name= "pmid8856816">{{cite journal |author=Sharpe M |title=Chronic fatigue syndrome |journal=Psychiatr. Clin. North Am. |volume=19 |issue=3 |pages=549–73 |year=1996 |pmid=8856816| doi = 10.1016/S0193-953X(05)70305-1 <!--Retrieved from CrossRef by DOI bot-->}}</ref><ref name= "pmid8474729">{{cite journal |author=Denz-Penhey H, Murdoch JC |title=General practitioners acceptance of the validity of chronic fatigue syndrome as a diagnosis |journal=N. Z. Med. J. |volume=106 |issue=953 |pages=122–4 |year=1993 |pmid=8474729 |doi=}}</ref><ref name= "pmid11051301">{{cite journal |author=Greenlee JE, Rose JW |title=Controversies in neurological infectious diseases |journal=Semin Neurol |volume=20 |issue=3 |pages=375–86 |year=2000 |pmid=11051301| doi = 10.1055/s-2000-9429 <!--Retrieved from CrossRef by DOI bot-->}}</ref><ref name= "pmid17535450">{{cite journal |author=Horton-Salway M |title=The ME Bandwagon and other labels: constructing the genuine case in talk about a controversial illness |journal=Br J Soc Psychol |volume=46 |issue=Pt 4 |pages=895–914 |year=2007 |pmid=17535450 |doi=10.1348/014466607X173456}}</ref> It may be necessary to embrace medical uncertainty, and also to accept patient experience in order to facilitate diagnosis, treatment, and recovery process. <ref name="pmid14572929">{{cite journal |author=Zavestoski S, Brown P, McCormick S, Mayer B, D'Ottavi M, Lucove JC |title=Patient activism and the struggle for diagnosis: Gulf War illnesses and other medically unexplained physical symptoms in the US |journal=Soc Sci Med |volume=58 |issue=1 |pages=161–75 |year=2004 |pmid=14572929| doi = 10.1016/S0277-9536(03)00157-6 <!--Retrieved from CrossRef by DOI bot-->}}</ref> It is suggested that a context of contested causation may have serious negative effects on healthcare for individuals. Contested causation may erode patient-provider trust, test the provider's self-assurance and capacity to share power with the patient, and raise problematic issues of compensation, reparation, and blame. <ref name="pmid12194900">{{cite journal |author=Engel CC, Adkins JA, Cowan DN |title=Caring for medically unexplained physical symptoms after toxic environmental exposures: effects of contested causation |journal=Environ. Health Perspect. |volume=110 Suppl 4 |issue= |pages=641–7 |year=2002 |pmid=12194900 |doi=}}</ref>
====Research priorities====
The etiology is still not known, and a major divide still exists over funding for research and treatment of [[physiological]] versus [[psychological]] and [[psychosocial]] aspects of the illness. The division is especially great between ME patient groups and psychological and psychosocial treatment advocates in Great Britain.<ref name= "pmid17535450"/>
====Government action====
According to the opinion of three Belgian authors of a 2007 paper published in ''Neuroendocrinology Letters'', in some countries it appears there is a political agenda to eliminate the scientific view that CFS is a medical disorder. They stated, the official acceptance of the condition would obviously mean the countries' health care systems would provide support for those patients, but if they are considered hypochondriacs, it becomes easier to deny them health care support.<ref name= "pmid18063928">
{{cite journal |author=Maes M, Coucke F, Leunis JC |title=Normalization of the increased translocation of endotoxin from gram negative enterobacteria (leaky gut) is accompanied by a remission of chronic fatigue syndrome |journal=Neuro Endocrinol. Lett. |volume=28 |issue=6 |pages=739–44 |year=2007 |pmid=18063928 |doi= |unused_data=|<!-- url = http://www.ediver.be/ediver/latest%20news/Maes%20M,%20leaky%20gut%20in%20CFS.pdf -->}}</ref>
US veterans with CFS/ME/FMS who have been diagnosed with chronic infections, cannot obtain adequate treatment for their condition. This lack of response due to a lack of effective programmes to assist veterans may ultimately be responsible for the transmission of the illness to non-veterans.<ref name= "pmid9633269">{{cite journal |author=Nicolson GL, Nicolson NL |title=Gulf War illnesses: complex medical, scientific and political paradox |journal=Med Confl Surviv |volume=14 |issue=2 |pages=156–65 |year=1998 |pmid=9633269| doi = 10.1080/13623699808409384 <!--Retrieved from CrossRef by DOI bot-->}}</ref>
====Support for patients====
Sufferers describe the struggle for healthcare and legitimacy due to bureaucratic denial of the condition because of its lack of a known etiology. Institutions maintain the exclusion of patient support by rhetorical arguments of the open-endedness of science to delay new findings of fact. Patient groups respond to the systematic nature of these exclusions by developing counter-arguments. This has resulted in an expensive and prolonged conflict for all involved.<ref name= "pmid16085344">{{cite journal | last = Dumit | first = J. | title = Illnesses you have to fight to get: facts as forces in uncertain, emergent illnesses.| journal = Soc Sci Med. | volume = Feb;62 | issue = 3 | pages = 577–90 | date = 2005 Aug 8 | pmid = 16085344}}</ref><ref name= "pmid9231495"/>
In 1998 it became known almost 13 million dollars for CFS research had been redirected or improperly accounted for by the United States CDC. The agency stated the need to respond to other public health emergencies. The director of a U.S. national patient advocacy group charged the CDC had a bias against studying the disease.<ref name= "pmid10932206">{{cite journal | last = Dove  | first = A. | title = GAO reports on CFS funding controversy| journal = Nat Med. | volume = 6 | issue = 8 | pages = 846 | date = 2000 Aug. |url = http://www.nature.com/nm/journal/v6/n8/full/nm0800_846a.html | pmid = 10932206 | accessdate = 2008-04-02 | doi = 10.1038/78579 }}</ref>
==See also==
*[[ME/CFS outbreaks|Outbreaks]]
*[[ME/CFS outbreaks|Outbreaks]]
*[[Notable people with chronic fatigue syndrome]]
*[[Notable people with chronic fatigue syndrome]]
*[[Cultural references of Chronic fatigue syndrome]]
*[[Cultural references of Chronic fatigue syndrome]]


==References==
{{reflist|2}}


{{MECFS}}
{{MECFS}}


[[Category:Disease]]
[[Category:Immune system disorders]]
[[Category:Immune system disorders]]
[[Category:Neurology]]
[[Category:Neurology]]

Latest revision as of 20:31, 28 February 2012

For patient information click here

Chronic fatigue syndrome/ Myalgic encephalomyelitis
ICD-10 G93.3
ICD-9 780.71
DiseasesDB 1645
MedlinePlus 001244
MeSH D015673

Chronic fatigue syndrome Microchapters

Home

Patient Info

Overview

Historical Perspective

Pathophysiology

Epidemiology & Demographics

Risk Factors

Causes of Chronic fatigue syndrome

Differentiating Chronic fatigue syndrome from other Diseases

Natural History, Complications & Prognosis

Diagnosis

History & Symptoms

Physical Examination

Lab Tests

Treatment

Medical Therapy

Chronic fatigue syndrome On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Chronic fatigue syndrome

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Chronic fatigue syndrome

CDC on Chronic fatigue syndrome

Chronic fatigue syndrome in the news

Blogs on Chronic fatigue syndrome

Directions to Hospitals Treating Chronic fatigue syndrome

Risk calculators and risk factors for Chronic fatigue syndrome

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Historical Perspective

Pathophysiology

Epidemiology & Demographics

Risk Factors

Causes of Chronic fatigue syndrome

Differentiating Chronic fatigue syndrome from other Diseases

Natural History, Complications & Prognosis

Diagnosis

History & Symptoms | Physical Examination | Lab Tests

Treatment

Related chapters


Template:MECFS

ca:Síndrome de fatiga crònica cs:Chronický únavový syndrom de:Chronisches Erschöpfungssyndrom it:Sindrome da fatica cronica he:תסמונת העייפות הכרונית lb:Chronescht Middegkeetssyndrom lt:Lėtinis nuovargis hu:Krónikus fáradtság szindróma nl:Chronischevermoeidheidssyndroom no:Kronisk utmattelsessyndrom sk:Chronický únavový syndróm sr:Хронични синдром замора fi:Krooninen väsymysoireyhtymä sv:Kroniskt trötthetssyndrom


Template:WikiDoc Sources

Retrieved from "https://www.wikidoc.org/index.php?title=Chronic_fatigue_syndrome&oldid=635074"