Guillain-Barre syndrome
Guillain-Barre syndrome is an acute, post-infectious autoimmune polyradiculoneuropathy causing rapidly progressive ascending flaccid weakness and areflexia. Diagnosis is clinical, supported by albuminocytologic dissociation on CSF and demyelinating changes on electrodiagnostic studies; first-line treatment is IVIG or plasma exchange with close monitoring for respiratory failure.
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What this article covers
- Overview
Definition: Guillain-Barre syndrome (GBS) is an acute, immune-mediated polyradiculoneuropathy causing rapidly progressive, symmetric, ascending flaccid weakness with areflexia, reaching nadir within 4 weeks of onset.
- Epidemiology
Incidence: GBS is the most common cause of acute flaccid paralysis worldwide, with an annual incidence on the order of 1 to 2 per 100,000 person-years, rising with age.
- Risk factors
Recent gastrointestinal or respiratory infection: the dominant identifiable antecedent, typically 1 to 4 weeks before symptom onset.
- Pathophysiology
Molecular mimicry: antecedent infection generates antibodies against pathogen surface antigens (for example, Campylobacter lipooligosaccharide) that cross-react with gangliosides on peripheral nerve…
- Clinical features
Ascending, symmetric weakness: classically begins in the lower extremities and ascends over hours to days to involve the trunk, upper limbs, and bulbar and respiratory muscles; weakness can occasionally begin proximally.
- Differential diagnosis
Botulism: descending, not ascending, paralysis with early prominent cranial nerve involvement (diplopia, ptosis, bulbar weakness) and pupillary involvement, without the sensory symptoms or back pain typical of GBS.
- Diagnosis
Clinical diagnosis: GBS is diagnosed on the clinical pattern of rapidly progressive, ascending, symmetric weakness with diffuse areflexia following a compatible antecedent illness; treatment should…
- Management
First, hospitalize every patient with suspected GBS for continuous respiratory and cardiovascular monitoring, regardless of initial severity; admit to an ICU setting if forced vital capacity is…
- Complications
Respiratory failure: the most immediately life-threatening complication, occurring in up to 25% of patients and the leading indication for ICU admission.
- Prognosis
Generally favorable: approximately 80% of patients are ambulatory independently by 6 months after onset.
- Prevention
No intervention prevents GBS itself, since it is a rare, unpredictable post-infectious phenomenon rather than a condition with an identifiable primary-prevention strategy.
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