Guillain-Barre Syndrome Flashcards
what is GBS?
- acute immune-mediated, inflammatory, demyelinating disorder with potential for chronic implications
- immune system attacks Schwann cells in peripheral nervous system
what is the most common form of GBS?
acute demyelinating inflammatory polyneuropathy (AIDP)
how is GBS characterized?
rapidly progressing ascending motor weakness and diminished reflexes
- sensory, autonomic and brainstem abnormalities may occur
T/F: GBS is the most common type of acute paralytic neuropathy?
TRUE
describe the incidence of GBS
- 1-2 cases/100,000
- peaks in frequency in young adults and 5th through 8th decades
- incidence rates increase with age, highest >60
- increases by 20% for every 10-yr increase in age
- seasonal relationships associated with infections
- males > females
describe the etiology of GBS
- triggering cause can be idiopathic, but 50% of cases occur shortly after a microbial (viral or bacteria) infection
- autoimmune disease
- allergic response
- other connections
- HIV, herpes
- vaccinations (very rare)
- surgery
describe the difference between bacterial and viral etiologies for GBS
- Bacterial
- ex → campylobacteriosis
- found in undercooked food, especially poultry
- Viral
- 50-75% of pts have history of URI or GI infection within last month
- usually precedes GBS dx by 1-4 weeks
- Zika, Epstein-Barr, COVID-19
typical progression of symptoms in GBS
- progression of symptoms from 12hrs to 28 days before plateau is reached
- plateau phase (nadir) for 2-4 weeks, then recovery proximal to distal
typical clinical presentation for GBS
- Motor weakness
- Hyporeflexia or areflexia
- Sensory impairments onset much later than motor
- CN involvement common
- CN 7 most often
- CN 3, 4, 6, 9 and 10
- ++Pain (neuropathic and MSK up to 90%)
- Autonomic dysfunction
- Respiratory difficulties
describe motor weakness in GBS
- rapidly progressive
- symmetrical
- distal → proximal
- leg weakness before arm in 90% of cases
describe CN involvement in GBS
- CN 7 most frequently invovled
- smiling
- frowning
- whistling
- drinking through a straw
- CN 3, 4, 6
- double vision
- CN 9 and 10
- dysphagia
- larygneal paralysis
describe autonomic dysfunciton in GBS
occurs up to 70% of cases and in 20% can be severe
- tachycardia
- arrhythmias
- OH
- wide fluctations in BP
how is GBS diagnosed?
- Clinical Eval
- CSF exam
- Nerve conduction studies
- MRI
CSF exam findings in GBS
- increased protein levels w/o pleocytosis
- protein elevation noted in 90% of cases by 2nd week
Nerve conduction studies findings in GBS
- reduced amplitude or absent motor AP
- decreased conduction velocity
- increased temporal dispersion
- latency prolongation of F wave
- nerve conduction block (axonal GBS)
MRI findings in GBS
- enhancement and swelling/thickening of spinal nerve roots