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Chronic Fatigue Syndrome


Chronic fatigue syndrome (CFS) is a chronic disorder characterized by debilitating fatigue of longer than six (6) months duration.

CFS causes nonspecific flu-like symptoms, including headaches, sore throats, swollen lymph nodes, fever and pain in the muscles and joints. It can cause an inability to think clearly and concentrate, memory loss, confusion, irritability, sleep disturbance and depression.


CFS began receiving widespread attention in the mid-1980s, after reports of about 100 cases in the Lake Tahoe area of California. Questions immediately arose as to whether the ill-defined mix of symptoms amounted to a discrete disease at all, and if so, whether it was a new condition.

Now that some of the dust has settled, CFS appears to be the same as what is called low natural killer cell syndrome in Japan and myalgic encephalomyelitis in England. In the U.S., CFS has also been called Epstein-Barr virus syndrome, chronic mononucleosis and the yuppie flu.

This debilitating, but seldom fatal, condition seems to affect many more women than men, and in adults more than children.

Today, CFS also is known as myalgic encephalomyelitis, postviral fatigue syndrome, and chronic fatigue and immune dysfunction syndrome.


The ailment has sometimes become a catch-all label for symptoms that cannot be otherwise explained. In reports and interviews, more than a dozen experts cited a trend in which many doctors have come to believe the syndrome is real, although most remain skeptical or are yet to be persuaded. Among those who are convinced that CFS is a real disease, three principal theories are being pursued.

One theory is that any of a number of infections agents and possibly chemicals can provoke the immune system to counterattack and somehow keep it in a lasting state of activation. According to this theory, the victims of chronic fatigue are those who cannot get rid of common infectious agents the way most people do, perhaps because of genetic differences. The result is a permanently activated state in which the immune system stays in high drive, as if to combat a continuing viral infection.

The second theory is that CFS is caused by viruses that infect parts of the brain and resist detection by the standard diagnostic tests. New laboratory and diagnostic measures are being developed to explore this concept.

The third theory holds that the syndrome is primarily a muscle disease and that the fatigue results secondarily from muscle dysfunction.




There is no standard laboratory test yet available for giving a reliable diagnosis of CFS. Doctors must rely on sharp clinical intuition and criteria set by the Center for Disease Control to judge whether a patient has the syndrome. The criteria is as follows:

Severe unexplained fatigue for over six (6) months that is:

  • new or with a definite time of onset
  • not due to continuing exertion
  • not resolved by rest
  • functionally impairing

And the presence of four or more of the following symptoms:

  • impaired memory or concentration
  • sore throat
  • painful lymph nodes in the neck or armpits
  • unexplained muscle soreness
  • pain that moves from one joint to another, without evidence of redness or swelling
  • generalized headaches
  • unrefreshing sleep
  • prolonged fatigue following previously tolerated exercise

Additionally, doctors must rule out other chronic fatigue producing conditions, such as hyper-and hypothyroidism, diabetes, fibromyalgia, food allergies, hormonal problems, environmental toxins, sleep disorders, anemia, depression, AIDs, multiple sclerosis, congestive heart failure, systemic inflammatory disease, hepatitis, Lyme disease, lupus and cancer.

Similar collections of symptoms, known by different names date back at least to the late 1800s. For a long time the key question was whether these symptoms represent a new disease or are a collection of complaints without clear cause. Many people who claimed to have symptoms of fatigue underwent tests that showed they had been exposed to the Epstein-Barr virus. However, further analysis has shown that many people exposed to the Epstein-Barr virus are free of symptoms, and not all those who have symptoms have been exposed to the Epstein-Barr virus.


As in many chronic illnesses, specific treatments that can remove the underlying cause or causes of CFS are unknown, although it can be very helpful to treat the symptoms. Perhaps the most important therapeutic step is accurate diagnosis because many patients with CFS fear that they may have a malignant condition, multiple sclerosis or another progressive illness. The usually favorable diagnosis may help reduce anxiety and promote acceptance.

Many symptom-specific treatments are currently used to treat symptoms in patients with CFS. Nonsteroidal anti-inflammatory agents are helpful in management of headache, arthralgia, anxiety and panic attacks. Perhaps the most widely used medications are tricyclic antidepressants, which control pain, improve sleep and alleviate depression. Initially, these agents should be given in low doses because many patients show an unusual sensitivity to them. Careful use of fluoxetine hydochloride (Prozac) or bupropion hydrochloride (Wellbutrin) may alleviate fatigue, but sometimes increase it.

People with CFS should eat a balanced diet and get enough rest. Physical, emotional and intellectual efforts should be paced, because too much stress can aggravate the symptoms.

Additionally, most people with CFS should work with a physical therapist to avoid muscle weakness that results from prolonged inactivity. This includes a regimen of graduated exercise, starting with a minimal amount of exertion and doing a little bit more each day.

Doctors also recommend cognitive-behavioral psychotherapy. This short-term form of psychotherapy encourages people to consider the role of psychological as well a social factors in their illness, to become more physically active, combat depression and anxiety, and improve confidence and illness control. Studies show that both graduated exercise and cognitive therapy can help greatly.

Most people’s CFS symptoms seem to plateau early in the illness and the symptoms wax and wane thereafter. Some people get completely better, although it is not clear how frequently this happens.


Are there any tests that need to be performed to rule out any other disease?

Will you be prescribing any medications to help treat this syndrome? What are the side effects?

What are the chances that the syndrome could increase and include more symptoms?

What are the chances the symptoms could last for months or years?

Is this condition contagious? If so, what measures should be taken to keep from spreading the disease?

Are there any other measures that can be taken to help relieve the symptoms?

The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, is heavily engaged in studying CFS. Based on what they have found so far, the riddle of CFS has no easy answer. Here are some of the findings:

  • Instead of a single causal agent, some scientists now suspect that several conditions may need to be met before the full-blown syndrome can occur. One hypothesis holds that people who become ill may have encountered one or more causal agents at a time when they were especially susceptible to an attack.
  • Researchers are currently following several promising avenues. For example, they are trying to determine whether CFS patients respond differently than healthy people do to strenuous exercise testing and whether they have more dramatic allergic reactions. They are also comparing the activities of certain hormones and of cytokines (chemical messengers produced by the immune system) in CFS patients and healthy people.
  • There is no convincing evidence that the illness is contagious in the true sense of the word, even though it may be triggered by an infectious agent. Although only a small proportion of patients regain the level of health they enjoyed before developing CFS, very few get progressively worse.
  • In recent years, many studies have found a wide variety of measurable abnormalities involving infectious agents and the immune systems and brains of people with CFS. While none of these abnormalities have been found in all patients with the illness, they indicate that CFS does indeed have real physiologic features. In addition, most of these abnormalities are not seen in mental illness, making it unlikely that CFS is a psychiatric disorder.