Diagnosing chronic fatigue syndrome

There's no test for chronic fatigue syndrome (CFS), but there are clear guidelines to help doctors diagnose thecondition.

It can take a long time for CFS to be diagnosed, as other conditions that cause similar symptoms need to be ruled out first.

You may be given some advice about managing your symptoms before a diagnosis is confirmed. See treating CFS for more information.

If you see your GP about persistent and excessive fatigue, they'll ask you about your medical history and may carry out a physical examination.

You may have Blood tests ,urine testsand scans to rule out other conditions, such as anaemia (lack of red blood cells), an underactive thyroid gland , or liver and kidney problems.

NICE guidelines for diagnosing CFS

Guidelines released in 2007 from the National Institute for Health and Care Excellence (NICE) statedoctors should considerdiagnosing CFS if a person has fatigue and all of the following apply:

  • it is new or had a clear starting point (it has not beena lifelong problem)
  • it is persistent or recurrent, orboth
  • it is unexplained by other conditions
  • it substantially reduces the amount of activity someone can do
  • it feels worse after physicalactivity

Theperson should alsohave one or more of these symptoms:

  • difficulty sleepingor insomnia
  • muscle or joint pain without inflammation
  • headaches
  • painful lymph nodes that are not enlarged
  • sore throat
  • poor mental function, such as difficultythinking
  • symptoms getting worse after physical or mental exertion
  • feeling unwellor having flu-like symptoms
  • dizziness or nausea
  • heart palpitations without heartdisease

This diagnosis should be confirmedby a clinicianafter other conditions have been ruled out. The symptoms listed above must have persisted for at least four months in an adult and three months in a child or young person.

For more information, read the NICE guidelines on CFS .

Chronic fatigue syndrome or PoTS?

It's likely some people diagnosed with chronic fatigue syndrome actually have postural tachycardia syndrome (PoTS).

PoTS is an abnormal increase in heart rate after sitting or standing up, which typically causes dizziness, fainting, sweating and other symptoms.


Content supplied by the NHS Website

Medically Reviewed by a doctor on 14 Apr 2015