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
CFS; Fatigue - chronic; Immune dysfunction syndrome
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 specific virus has been identified as the cause.
Studies suggest that CFS may be caused by inflammation along the nervous system, and that this inflammation may be some sort of immune response or process.
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 of CFS are similar to those of most common viral infections (muscle aches, headache, and fatigue). They come on within a few hours or days and last for 6 months or more.
Physical examination may confirm fever, lymph node tenderness, lymph node swelling, or other symptoms. The throat may appear red without drainage or pus.
The health care provider will diagnose 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, although a variety of tests are usually done to exclude other possible causes of the symptoms.
The following test results, while not specific enough to diagnose CFS, are seen consistently in people who are eventually diagnosed with the disorder:
There is currently no cure for 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. Mild physical exercise may also be helpful.
The long-term outlook for patients with CFS is variable and difficult to predict when symptoms first start. Some patients have been reported to completely recover after 6 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 are more likely to recover completely than those patients who don't seek treatment.
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
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 RE, Bope ET. Conn's Current Therapy 2008. 60th ed. Philadelphia, Pa: Saunders Elsevier; 2008.