Chronic fatigue syndrome history and symptoms

Signs and symptoms
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.

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.

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.

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:


 * 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.

Sudden onset cases
The majority of CFS cases start suddenly, usually accompanied by a "flu-like illness"  which is more likely to occur in winter,  while a significant proportion of cases begin within several months of severe adverse stress. Many people report getting a case of a 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. One study reported CFS occurred in some patients following a vaccination or a blood transfusion. 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. Patients with Lyme disease may, despite a standard course of treatment, "evolve" clinically from the symptoms of acute Lyme to those similar to CFS. This has become an area of great controversy.

Activity levels
Patients report critical reductions in levels of physical activity and are as impaired as persons whose fatigue can be explained by another medical or a psychiatric condition. 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, rheumatoid arthritis, heart disease, end-stage renal disease, chronic obstructive pulmonary disease (COPD) and similar chronic conditions. The severity of symptoms and disability is the same in both genders, and chronic pain is strongly disabling in CFS patients, but despite a common diagnosis the functional capacity of CFS patients varies greatly. 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.