Guillain- Barré syndrome

Question 1

What is Guillain-Barré syndrome?

Question 2

what is the pathophysiology behind Guillain-Barré syndrome?

Answer 2

• Myelin autoantigen picked up by APCs (e.g. dendritic cells)
• APCs present autoantigen to T helper cells and produce cytokines
• B cells and macrophages are activated
• B cells produce autoantibodies and macrophages attack the myelin sheath on peripheral neurones.

Question 3

What causes GB syndrome?

Answer 3

Guillain Barré syndrome usually happens after a trigger:

Campylobacter jejuni (bacterial infection)

CMV

Mycoplasma

Zoster

HIV

EBV

Post-vaccinations

Question 4

Why is it thought GB syndrome occurs after infection?

Question 5

What are the risk factors of GB syndrome?

Answer 5

Acute infection

^^ age

Males

Question 6

What are the symptoms of GB syndrome?

Answer 6

1. Initially loss of sensation (ascending paraesthesia)- usually affects nerves for vibration and touch sensation
2. Bilateral ascending flaccid weakness of limbs (which peak within 4 weeks)- this is when the motor nerves are affected.
3. Dysphagia, blurred vision, dysarthria and facial weakness if cranial nerve involvement
4. Autonomic dysfunction- sweating
5. Breathing difficulties if diaphragmatic innervation affected (hypoventilation)

Symptoms will vary depending on which nerve is affected. Symptoms are progressive for 4 weeks (then followed by recovery).

Question 7

What is different about GB syndrome as opposed to other neuropathies?

Answer 7

Proximal muscles are more affected (e.g. trunk, respiratory muscles and cranial nerves)

Question 8

What are the signs of GB syndrome?

Question 9

What is a complication of GB syndrome and what signs should you look out for?

Answer 9

Patient might be experiencing Type II respiratory failure. O/E, note:

• CO2 flap
• Bounding pulse
• Drowsiness

This will need mechanical ventilation.

Question 10

What investigations would you do? And what would they show?

Answer 10

1. Nerve conduction studies (EMG)- slow conduction as reduced nerve conduction velocity
2. CSF sample via lumbar puncture- increased albumin, with nil increase in WBC. This is called albuminocytologic dissociation.
3. Bloods- serum anti-ganglioside antibodies in the “Miller Fisher” variant of Guillain- Barre syndrome
4. Spirometry- Measure FVC 4 hourly if respiratory involvement
5. Can do MRI to visualise any thickening of the spine nerve roots

Question 11

What is the treatment of GB syndrome?

Answer 11

Aims at reducing symptoms

• IV Ig antibodies 0.4g/kg/24hours
• Plasmapheresis- plasma is filtered out for the autoantibodies and returned to the patient via dialysis
• Pain management- carbamazepine

Recovery is long and nerves will get remyelinated

Supportive therapy:

• Monitor FVC (respiratory support)
• Monitor ECGs for arrhythmia detection and have some DVT prophylaxis (haemodynamic support)
• Do some physiotherapy

Question 12

What is the prognosis of GB syndrome?

Answer 12

Prognosis- good. 85% make it to full recovery. 10% are unable to walk alone at 1 yr