Chronic fatigue syndrome

Overview

ME/CFS is a neuroimmune condition characterised by profound fatigue not explained by other causes, significantly worsened by exertion. NICE 2021 (NG206) removed graded exercise therapy and repositioned CBT.

Presentation

All five core features must be present for diagnosis (symptoms ≥4 months in adults, ≥3 months in children/young people):

•Debilitating fatigue - worse after activity, not primarily from exertion, not relieved by rest

•Post-exertional malaise (PEM) - worsening of ALL symptoms (physical, cognitive, immune) delayed 12-48 hours after exertion, lasting days to weeks

•Unrefreshing sleep - waking unrestored; insomnia or hypersomnia

•Cognitive impairment - 'brain fog'; memory, concentration, word-finding, processing speed

•Orthostatic intolerance - lightheadedness, palpitations, worsening on standing; may meet PoTS criteria

⚠️

PEM is not simply tiredness after exercise - it is a pathological, delayed worsening of all symptoms. Pushing through it causes harm. This is why GET was removed from guidance.

Investigations

No diagnostic test exists - investigations exclude treatable organic causes before confirming diagnosis.

🥇 First-line

•FBC, TFTs (TSH), fasting glucose/HbA1c, ESR, CRP, U&Es, LFTs, calcium, urinalysis

🥈 Second-line

•coeliac screen (anti-TTG IgA), active B12/folate if macrocytosis, sleep study if OSA suspected

Management

🥇 First-line

•Energy management/pacing - identify individual energy envelope and stay within it; delivered by occupational therapist with ME/CFS expertise

•Supported self-management - information, validated resources, regular review

•MDT referral to specialist ME/CFS service

🥈 Second-line

•CBT - offered only to support coping with chronic illness, comorbid anxiety/depression, or sleep difficulties; NOT a treatment for ME/CFS itself

•Symptomatic pharmacological management:

•Sleep disturbance - low-dose amitriptyline or melatonin

•Pain - NSAIDs or paracetamol

•Orthostatic intolerance/PoTS - fludrocortisone or propranolol under specialist guidance; increased fluid and salt intake, compression stockings, head-of-bed elevation

🚨

Graded exercise therapy (GET) must NOT be offered. It is based on a discredited deconditioning model and consistently causes harm. Pacing (staying within the energy envelope) is fundamentally different from GET (progressively pushing beyond it).

Follow-up

•Review every 3-6 months in stable patients; more frequently if newly diagnosed, deteriorating, or severely affected

•Reassess for organic pathology if presentation changes significantly or new symptoms emerge

•Assess for depression and anxiety as comorbidities at each review

Prognosis

•Full recovery possible, particularly in children/young people and milder/shorter illness

•Many adults have prolonged or fluctuating course; significant minority remain severely disabled long-term

•Better outcomes associated with early diagnosis, appropriate energy management, and avoidance of GET