Guillian-Barre Syndrome Flashcards
What type of polyneuropathy is Guillian Barre syndrome?
An acute, inflammatory demyelinating polyradiculopathy (AIDP)
What often triggers GB syndrome?
An infection, usually GI or URTI classically campylobacter jejuni Also: CMV, mycoplasma, zoster, HIV, EBV Or other immune system stimulants e.g vaccination, pregnancy, trauma, surgery Up to 40% no precipitating factor found
Describe the pathophysiology
The infection causes the production of antibodies against peripheral nerves. Myelin is damaged and transmission is reduced or even blocked.
Cross reaction of antibodies with gangliosides in PNS
What clinical features are associated?
Almost always motor involvement, sometimes also sensory
+/- autonomic features
A few weeks after infection a symmetrical ascending muscle weakness starts
Usually begins in lower legs, ascends to upper limbs and face
Proximal muscles are more affected e.g trunk, respiratory and cranial nerves esp VII
Mild sensory symptoms
Areflexia
Cranial nerve involvement - especially bilateral facial weakness
Autonomic dysfunction
How much time does it usually progress over?
Approx 4 weeks before recovery
Although may advance very quickly, affecting all limbs at once - resulting in paralysis
Some patients progress for longer than 8 weeks - tend to have a relapsing course requiring repeated treatment over long periods of time (chronic condition)
Is pain common?
Yes
Often back pain - it is a radiculopathy ie condition starts in nerve roots
Patients often notice mild back pain before weakness and sensory symptoms
What helps distinguish it from other peripheral neuropathies?
Proximal muscles more affected
Also trunk, resp and cranial nerves can be affected
What autonomic signs can occur?
Sweating Tachycardia Dysrythmias BP changes hypertension or hypotension Diarrhoea Urinary retention
Are sensory signs often present or absent?
Often absent, but they do occur in mild form
What investigations are done?
Nerve conduction studies - in first week may only show subtle abnormalities e.g prolonged F waves that indicate nerve roots involvement
LP - CSF increased protein,<10 WBCs per mm3
Consider serology - campylobacter if GI upset, CMV,EBV,HSV,HIV, mycoplasma
Stool culture
Throat swab
Anti-ganglioside antibodies
What percentage make a complete or almost complete recovery?
70% at 1 year
What involvement necessitates transfer to ITU?
Respiratory - ventilate sooner rather than later
Is complete paralysis compatible with complete recovery?
Yes
What is the mortality rate?
3-5%
How should it be management?
IV immunoglobulin for 5 days
Plasma exchange can work too
Steroids have NO role
Recovery often occurs without specific treatment
