Chronic fatigue syndrome, or CFS, is a complex and debilitating disorder characterized by profound fatigue that is not improved with sleep or bed rest and that gets worse with physical or mental activity.  There is no known lab test to help diagnosis chronic fatigue syndrome.  To receive a diagnosis of CFS, a person must satisfy the two following criteria.First, a patient must have severe chronic fatigue for six months or longer.  The fatigue can not be part of another known medical condition.Second,  a patient must concurrently have four or more of the following symptoms:

Defining CFS Symptoms

• Extreme fatigue that has lasted at least six months
• Post-exertional malaise, lasting more than 24 hours
• Non-refreshing sleep
• Insomnia
• Substantial impairment in memory/concentration
• Muscle pain
• Pain in multiple joints; without swelling or redness
• Sore throat
• Headaches of a new type, pattern or severity
• Tender lymph nodes in neck or armpit

Causes of Chronic Fatigue Syndrome

Despite an intensive, nearly 20-year search, the cause of CFS remains unknown.

Possible causes of CFS which are being considered

• Stress
• Organ system dysfunction
• Psychological causes
• Endocrine dysfunction (adrenals, thyroid, etc.)
• Nervous systems dysfunction
• Immune dysfunction
• Many different infectious agents
• Genetic and environmental factors