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Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) is a condition that causes marked long-term fatigue and other symptoms which are not caused by any other known medical condition. There is no test to diagnose this condition. The diagnosis is made in people who have a certain set of symptoms (which can vary in their type and severity).

There is even controversy about what to call this condition. In the United States it's known as Chronic Fatigue Syndrome (CFS) or Chronic Fatigue Immune Dysfunction Syndrome (CFIDS). In Europe, Canada, and other parts of the world it's known as Myalgic Encephalomyelitis (ME) or Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME).

The following symptoms are grouped into four general categories. Each symptom is followed by the percentage of people with CFS/ME who experience them. These percentages are based upon information reported by Dr's. Bell, Cheney, Fudenberg, Goldstein, Jessop, Komaroff, Peterson, and information from Katrina Berne,Ph.D.

Grouping symptoms into categories is done for convenience. It is likely that all symptoms are related to neuroimmune dysfunction.

The list above represents a range of reported symptoms in different studies. Patients do not necessarily experience these symptoms all the time. In most cases only one-third to one-half of those reporting individual symptoms indicated that they experienced the symptom at all times.

People with CFS/ME may experience symptoms other than those listed above. Some of the symptoms reported may have been experienced prior to the onset of CFS/ME in a milder or different form. Additionally, other illnesses or conditions may exist simultaneously with CFS/ME, complicating the diagnostic problems and often causing lack of clarity as to which symptoms are attributable to which conditions.

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 CFS/ME Physical Symptoms
Symptoms % Affected
Fatigue, often accompanied by non-restorative sleep, generally worsened by exertion 50-90%
Nausea 60-90%
Irritable bowel syndrome (diarrhea, nausea, gas, abdominal pain) 50-90%
Chronic sore throat 50-90%
Fevers, chills, sweats, feeling hot often 60-95%
Muscle and/or joint pain, neck pain 65-95%
Bladder/prostate problems, frequent urination 20-95%
Low blood pressure 86%
Recurrent illness and infections 70-85%
Malaise 80%
Heat/cold intolerance 75-80%
Painful and/or swollen lymph nodes 50-80%
Systemic yeast/fungal infections 30-80%
Fungal infection of skin and nails 71%
Weight gain 50-70%
Increased/severe PMS (Premenstrual Syndrome) 70%
Swelling, fluid retention 55-70%
Shortness of breath 30-70%
Subnormal body temperature 65%
Severe allergies 40-60%
Sensitivities to medicines, inhalants, odors, and foods 25-65%
Difficulty swallowing 55-60%
Heart palpitations 40-60%
Sinus pain 56%
Rash or flushing of face 35-45%
Chest pain 40%
Hair loss 20-35%
Eye pain 30%
Pressure at the base of the skull 30%
Weight loss 20-30%
Tendency to bruise easily 25%
Vomiting 20%

Other CFS/ME Physical Symptoms
Dryness of mouth, eyes
Pressure sensation behind eyes
Frequent canker sores
Periodontal disease, pain in teeth, loose teeth
TMJ syndrome
Mitral valve prolapse
Carpal tunnel syndrome
Serious cardiac rhythm disturbances
Pyriform muscle syndrome, causing sciatica
Thyroid inflammation
Hypoglycemia or hypoglycemia like symptoms
Swelling of nasal passages
Micro vascular disease

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 Neurological/Central Nervous System Symptoms
Symptoms % Affected
Confusion, inability to think clearly 75-100%
Concentration/attention deficit 70-100%
Sleep disorder/disturbance (insomnia, un restorative sleep, unusual nightmares) 65-100%
Muscle weakness 85-95%
Headache 75-95%
Memory problems (especially short-term memory) 80-90%
Photosensitivity 65-90%
Disequilibrium, spatial disorientation, dizziness, vertigo 60-90%
Spaceyness, light-headedness 75-85%
Muscle twitching, involuntary movements 55-80%
Aphasia and/or dyscalculia 75-80%
Alcohol intolerance 45-75%
Seizure-like episodes 70%
Coordination problems/clumsiness 60%
Paresthesias (numbness, tingling or other odd sensations in face and/or extremities) 25-60%
Visual disturbance (scratchiness, blurring of vision, "floaters") 45-55%
Episodic hyperventilation 40-45%
Fainting or blackouts 40%
Strange taste in mouth (bitter, metallic) 25%
Temporary paralysis after sleeping 20%
Earache 20%

Other CFS/ME Symptoms Reported
Decreased sex drive
Hallucinations (sensory perception experienced in the absence of an external stimulus)
Alteration of taste, smell, hearing

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Neurological Channelopathies

The symptoms of CFS/ME patients display some similarities to those found in neurological channelopathies. One of the symptoms CFS/ME has in common with ion channel disorders is its fluctuating nature. All known channelopathies of the excitable tissues result in episodic episodes of fatigue. As in CFS/ME some cause symptoms that indicate both peripheral and central disruption. Neurological channelopathies (hypoakalemic periodic paralysis, episodic ataxia) are often characterized by sudden attacks of fatigue, weakness, cramping or even paralysis. As in CFS/ME many channelopathies can be induced by physical activity and/or stress.

While there has been much discussion regarding the need for longitudinal studies to capture the fluctuations present in CFS/ME Many question how episodic CFS/ME is. Their experience is that it is no more episodic than would probably be expected in a chronic disorder; that is, there are better or worse days but few days with truly dramatic shifts in well-being.

CFS/ME patients share with epileptics a predisposition to several autonomic related symptoms such as frequent near syncope (fainting) and low blood pressure, particularly during TILT table testing. A great deal of evidence since 1999 indicates many CFS/ME patients display abnormalities during TILT table testing or during standing.

CFS/ME patients share with migraine sufferers such symptoms as headache, confusion, increased sensitivity to lights, sounds and smells as well as exacerbated responses to serotonin. Symptom exacerbation during menstruation and muscle pain, disequilibrium and unusual sweating are often seen in both diseases. White brain matter abnormalities and reduced cerebral blood flows are also seen in both diseases and stress, alcohol and caffeine can exacerbate symptoms in both diseases. Transient or chronic fatigue is also common in migraine.

Finally, there is evidence of a channelopathy in CFS/ME. Some indirect evidence of ion channel disruption is provided by Chaudhuri et al's finding of increased resting energy expenditure (REE) in CFS/ME patients. Since about 25% of the energy expended during resting goes to maintaining ion gradients in the cell, the authors speculate the increased REE seen in CFS/ME could be due to compensation for faulty ion channel functioning. CFS/ME patients also appear to be particularly susceptible to some substances (alcohol, anesthesia, some cholesterol lowering drugs) known to effect either membrane integrity (alcohol) and/or ion function (anesthethetics). Indeed fatigue is a common symptom of a new anti-epileptic drug, dezinamide, targeting sodium channels. Results from a thallium scan of the cardiac muscle in CFS/ME patients suggest a potassium ion channel dysfunction that may be responsible for the cardiomyopathy reported by Lerner and now advocated by Cheney. Chaudhuri and Behan believe a potassium channelopathy is mostly likely to occur in CFS/ME.

Potential causes of channel dysfunction - The natural history of CFS/ME suggests that an early pathogenic or toxic insult often occurs. Several viruses, including HIV and the picornaviruses are able to alter ion channel flow. Herpes viruses have also been linked, interestingly enough given their history in CFS/ME, to altered ion channel functioning. Ciguatoxin, a neuronal sodium channel disrupter, produces many symptoms, including fatigue, similar to those that occur in CFS/ME. Studies indicate a substantial number of CFS/ME patients have extremely high levels of the ciguatera epitope. Toxic insults from organophosphate's, lead, insecticides, pesticides can also alter ion channel activity.

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 Emotional/Psychological Symptoms
Symptoms % Affected
Anxiety 70-90%
Mood swings, excessive irritability, overreaction 70-90%
Depression 65-90%
Personality change 55-75%
Panic attacks 30-40%

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