Guillain-Barré Syndrome

Question 1

Define

Answer 1

Acute inflammatory demyelinating polyneuropathy

• RAPID ONSET muscle weakness due to damage to the peripheral nervous system
• An inflammatory process where antibodies after a recent infection react with self-antigen on myelin/neurones

Question 2

Signs

Answer 2

General MOTOR Examination

• Hypotonia
• Flaccid paralysis
• Arreflexia (ascending upwards from feet to head)

General SENSORY Examination

• Impairment of sensation in multiple modalities (ascending from feet to head)

Cranial Nerve Palsies

• Facial nerve weakness
• Abnormality of external ocular movements
• If pupil constriction is affected, consider botulism

Type II Respiratory Failure

• Due to paralysis of respiratory muscles

Autonomic Function

• Assess postural blood pressure change and arrhythmias

Question 3

Investigations

Answer 3

Lumbar Puncture

• HIGH protein
• NORMAL cell count and glucose

Nerve Conduction Study

• Reduced conduction velocity
• NOTE: it may be normal in the early stages of the disease

Bloods

• Anti-ganglioside antibodies in Miller-Fisher variant + 25% of Guillain-Barre cases

Spirometry

• Reduced fixed vital capacity - suggests ventilatory weakness

ECG

• Arrhythmias may develop

Question 4

Causes

Answer 4

There is often no aetiological trigger identified (40% of cases are idiopathic)

Other causes:

• Post-infection (1-3 weeks) - bacterial, HIV, herpes viruses
• Malignancy - e.g. lymphoma
• Post-vaccination

Question 5

Symptoms

Answer 5

PROGRESSIVE symptoms

< 1 month duration of:

• ASCENDING symmetrical limb weakness (lower > upper)
• ASCENDING paraesthesia

Cranial nerve involvement (leading to, for example, dysphagia, dysarthria, facial weakness)

Respiratory muscles may be affected in SEVERE cases

Miller-Fisher Variant (RARE) = ophthalmoplegia, ataxia, arreflexia

Question 6

Epidemiology

Answer 6

UK incidence: 1-2/100,000

Affects all age groups