Chronic Fatigue Syndrome - Diagnosis

One step in diagnosing CFS is taking a medical history. Doctors ask patients about their symptoms, about other illnesses they have had, and about medications they are taking. They also conduct a physical examination and may order laboratory tests. They try to eliminate causes of the person's symptoms other than CFS. In the United States, many doctors use a standard created by the CDC for defining CFS. According to this standard, patients have chronic fatigue syndrome if they meet both of the following criteria:

• Chronic (continuous and ongoing) fatigue for at least six months. The condition is not caused by activity and is not relieved by rest. It greatly interferes with the person's job, school, social, or personal activities.
• Four or more of the following symptoms: loss of short-term memory or the ability to concentrate; sore throat; tender lymph nodes; muscle pain; pain in more than one joint without swelling or redness; headaches not previously experienced by the patient; failure of sleep to help the patient feel better; and a feeling of discomfort or tiredness that lasts more than twenty-four hours following exercise. In addition, these symptoms must occur more than once over a six-month period.