FFS: Guillain‑Barré syndrome

Sensory and autonomic symptoms may be present. Variants may involve cranial nerves or be pure motor. Severe cases can result in death due to respiratory muscle paralysis or autonomic dysfunction.

The primary ED priority is exclusion of spinal cord pathology (e.g. disc prolapse, tumour, hematoma, epidural abscess).

Pathophysiology

GBS is typically a post-infectious immune-mediated disorder of the peripheral nervous system.

Two-thirds of patients report a preceding respiratory or gastrointestinal infection.

Variants include:

• Acute inflammatory demyelinating polyradiculoneuropathy (AIDP) – most common
• Miller Fisher syndrome (MFS) – ophthalmoplegia, ataxia, areflexia
• Acute motor axonal neuropathy (AMAN) – pure motor, typically in children
• Acute motor-sensory axonal neuropathy (AMSAN) – severe, fulminant form

Causes

Infective agents:

• Campylobacter jejuni (most common)
• Mycoplasma, HIV, CMV, EBV, measles, mumps, varicella, influenza

Post-vaccination:

• Presumed autoimmune

Other associations:

• Malignancy (e.g. lymphoma)
• Autoimmune diseases (e.g. SLE, sarcoidosis)
• Immunosuppression

Prognostic Features

Poor prognostic indicators:

• Older age
• Rapid onset (<7 days)
• Need for ventilation
• Distal motor response amplitude <20% normal
• Preceding diarrhoeal illness

Outcomes:

• 80% recover completely or with minor deficits
• 10% prolonged illness/ventilator dependency
• 3% remain wheelchair-bound
• 5% mortality despite ICU care

Clinical Features

Typical presentation:

• Muscle weakness: Rapid onset (days–4 weeks), symmetric, flaccid, distal to proximal (legs → arms → cranial nerves). Up to 1/3 require ventilation.
• Reflex loss: Progressive, symmetric
• Sensory symptoms: Paresthesiae (50%), minimal loss
• Autonomic dysfunction (70%): Tachycardia, arrhythmias, BP lability, retention, ileus
• Pain: May include back pain
• No fever

Course: Nadir at 2–4 weeks; gradual recovery. >8 weeks progression suggests CIDP.

Differential Diagnosis

Includes acute paralysis/neuromuscular disorders:

Neurological:

• Acute spinal cord compression
• Transverse myelitis
• Poliomyelitis, botulism, diphtheria
• Nutritional/toxic neuropathies (e.g. B12, arsenic, lead)
• Paraneoplastic, mononeuritis multiplex
• Envenomation, porphyria

Muscular:

• Myasthenia gravis, polymyositis

Other:

• Conversion disorder

Investigations

Blood tests (exclude differentials):

• FBC, CRP/ESR, U&Es, glucose
• Folate/B12, CK

Imaging:

• MRI spine: To exclude myelopathy (preferred)
• CT spine: Alternative if MRI unavailable

Lumbar puncture:

• Contraindicated if myelopathy not excluded
• CSF findings: ↑ Protein (>0.4 g/L), normal cells (albuminocytologic dissociation)

Nerve conduction studies:

• Reduced conduction velocity (supportive)

Management

All patients require hospital admission and ICU referral

1. Respiratory care:

• Monitor VC 4-hourly
• Intubate if VC <20 mL/kg or MIP <30 cmH2O

2. Cardiac monitoring:

• For autonomic instability

3. Specific therapies:

• IV immunoglobulin (IVIG) or plasma exchange (equal efficacy)
• Glucocorticoids are not effective

4. Pain management:

• Gabapentin, carbamazepine
• Opioids often required

5. Drug precautions:

• Avoid hypotensive drugs
• Avoid suxamethonium if intubating

6. Other support:

• IDC for retention, enteral feeding if ileus
• DVT prophylaxis
• Physiotherapy (chest, joint mobility, pressure care)
• Psychological support (depression common)

Disposition

All patients with GBS require ICU-level care and neurology input.

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References

Publications

• Nguyen TP, Taylor RS. Guillain-Barre Syndrome. 2023 Feb 7. In: StatPearls 

FOAMed

• Cadogan M. Guillain–Barré syndrome. Eponymictionary
• Nickson C. Guillain-Barré Syndrome (GBS). LITFL
• Nickson C. GBS vs CIP. LITFL
• Cadogan M. Miller Fisher Syndrome. LITFL