Guillain-Barre Syndrome

Question 1

What is GBS?

Answer 1

immune-mediated demyelination of the peripheral nervous system often triggered by an infection

Question 2

What infection classically triggers GBS?

Answer 2

Campylobacter jejuni
=> may be a history of gastroenteritis

Question 3

Describe the pathogenesis of GBS

Answer 3

cross-reaction of antibodies with gangliosides in the peripheral nervous system

Question 4

What antibody can be found in 25% of patients with GBS

Answer 4

anti-GM1 antibodies

Question 5

Variant of Guillain-Barre syndrome
associated with ophthalmoplegia, areflexia and ataxia

Answer 5

Miller Fisher syndrome

Question 6

Describe the pattern of disease onset in Miller Fisher syndrome compared to GBS

Answer 6

• eye muscles are typically affected first
• presents as a descending paralysis rather than ascending

Question 7

Antibodies found in Miller Fisher syndrome

Answer 7

anti-GQ1b antibodies

Question 8

Clinical features of GBS

Answer 8

• ascending weakness (legs first)
• reflexes reduced/absent
• sensory symptoms are mild (e.g. distal paraesthesia)

Question 9

Less common features of GBS

Answer 9

• respiratory muscle weakness
• CN involvement (diplopia, facial nerve palsy, oropharyngeal weakness)
• urinary retention
• diarrhoea

Question 10

Investigations

Answer 10

LP
nerve conduction studies

Question 11

CSF findings in GBS

Answer 11

high protein
normal white blood cell count (albuminocytologic dissociation)

Question 12

Nerve conduction study findings

Answer 12

• decreased motor nerve conduction velocity (due to demyelination)
• prolonged distal motor latency
• increased F wave latency

Question 13

Management of GBS

Answer 13

IV immunoglobulins (IVIG) or plasma exchange

FVC regularly to monitor respiratory function

Question 14

Poor prognostic features

Answer 14

• age > 40 years
• poor upper extremity muscle strength
• Hx of a diarrhoeal illness (specifically Campylobacter)
• high anti-GM1 antibody titre
• need for ventilatory support