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Chronic fatigue syndrome

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Alternative Names   

CFS; Fatigue - chronic; Immune dysfunction syndrome

Definition    Return to top

Chronic fatigue syndrome is a condition of prolonged and severe tiredness or weariness (fatigue) that is not relieved by rest and is not directly caused by other conditions. To be diagnosed with this condition, your tiredness must be severe enough to decrease your ability to participate in ordinary activities by 50%.

See also: Fatigue

Causes    Return to top

The exact cause of chronic fatigue syndrome (CFS) is unknown. Some researchers suspect it may be caused by a virus, such as Epstein-Barr virus or human herpes virus-6 (HHV-6). However, no distinct viral cause has been identified.

Recent studies have shown that chronic fatigue syndrome may be caused by inflammation of pathways in the nervous system, and that this inflammation may be some sort of immune response or process. CFS may occur when a viral illness is complicated by a problem with the body's immune response. Other factors such as age, prior illness, stress, environment, or genetics may also play a role. CFS most commonly occurs in women ages 30 to 50.

The Centers for Disease Control (CDC) describes CFS as a distinct disorder with specific symptoms and physical signs, based on ruling out other possible causes. The number of persons with CFS is unknown.

Symptoms    Return to top

Symptoms of CFS are similar to those of most common viral infections (muscle aches, headache, and fatigue), often developing within a few hours or days and lasting for 6 months or more.

Main symptoms:

Other symptoms:

Exams and Tests    Return to top

Physical examination may confirm the fever, lymph node tenderness, lymph node swelling, or other symptoms. The throat may appear red without drainage or pus.

The health care provider can presume a diagnosis of chronic fatigue syndrome (CFS) only after ruling out all other known possible causes of fatigue, such as:

A diagnosis of CFS must include:

There are no specific tests to confirm the diagnosis of CFS, though a variety of tests are usually done to exclude other possible causes of the symptoms.

There are some typical findings on tests that, while not specific enough to diagnose CFS, are seen consistently in people who are eventually diagnosed with the disorder. These include:

Treatment    Return to top

There is currently no treatment that has been proven to be effective in curing CFS. Instead, the symptoms are treated. Many people with CFS experience depression and other psychological problems that may improve with treatment.

Some of the proposed treatments include:

Some medications can cause adverse reactions or side effects that are worse than the original symptoms of chronic fatigue syndrome.

Patients with CFS are encouraged to maintain active social lives, and mild physical exercise may also be helpful.

Outlook (Prognosis)    Return to top

The long-term outlook for patients with CFS is variable and difficult to predict at the initial onset. Some patients have been reported to completely recover after six months to a year. Others may take longer for a complete recovery.

Some patients report never returning to their pre-illness state. Most studies report that patients treated in an extensive rehabilitation program have a better prognosis of improving significantly than those patients who don't seek treatment.

Possible Complications    Return to top

When to Contact a Medical Professional    Return to top

Call for an appointment with your health care provider if you experience persistent, severe fatigue, with or without other symptoms of this disorder. Other more serious disorders can cause similar symptoms and should be ruled out.

See also:

Chronic fatigue syndrome - resources

References    Return to top

Harris ED, Budd RC, Genovese MC, Firestein GS, Sargent JS, Sledge CB. Kelley's Textbook of Rheumatology. 7th ed. St. Louis, Mo: WB Saunders; 2005:525.

Rakel P, ed. Conn’s Current Therapy 2006. 58th ed. Philadelphia, Pa: WB Saunders; 2006: 138-141.

Update Date: 8/22/2006

Updated by: Lisa Christopher-Stine, M.D., M.P.H., Assistant Professor of Medicine, Division of Rheumatology, Department of Medicine, Johns Hopkins University,Baltimore, MD. Review provided by VeriMed Healthcare Network.

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