Chronic fatigue syndrome

Diagnosed after at least 4 months of disabling fatigue affecting mental and physical function more than 50% of the time in the absence of other disease which may explain symptoms

Epidemiology

• more common in females
• past psychiatric history has not been shown to be a risk factor

Fatigue is the central feature, other recognised features include

• sleep problems, such as insomnia, hypersomnia, unrefreshing sleep, a disturbed sleep-wake cycle
• muscle and/or joint pains
• headaches
• painful lymph nodes without enlargement
• sore throat
• cognitive dysfunction, such as difficulty thinking, inability to concentrate, impairment of short-term memory, and difficulties with word-finding
• physical or mental exertion makes symptoms worse
• general malaise or 'flu-like' symptoms
• dizziness
• nausea
• palpitations

Investigation

• NICE guidelines suggest carrying out a large number of screening blood tests to exclude other pathology e.g. FBC, U&E, LFT, glucose, TFT, ESR, CRP, calcium, CK, ferritin*, coeliac screening and also urinalysis

Management

• cognitive behaviour therapy - very effective, number needed to treat = 2
• graded exercise therapy - a formal supervised program, not advice to go to the gym
• 'pacing' - organising activities to avoid tiring
• low-dose amitriptyline may be useful for poor sleep
• referral to a pain management clinic if pain is a predominant feature

Better prognosis in children

*children and young people only