Condition

Guillain-Barre Syndrome

Editors: José Ángel Berciano Blanco MD; Matthew B. Bevers MD, PhD; Zbigniew Fedorowicz PhD, MSc, DPH, BDS, LDSRCS; Alexander Rae-Grant MD, FRCPC, FAAN

American College of PhysiciansProduced in collaboration with American College of Physicians
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Background Information

Description

  • Guillain-Barre Syndrome (GBS) is a rare immune-mediated acute polyradiculoneuropathy, usually following an infection or other immune-stimulating event and presenting with bilateral weakness, impaired reflexes, and sensory abnormalities, that progresses over 1-4 weeks to potentially life-threatening severity requiring mechanical ventilation before plateauing for up to several months with later improvement.,

Also Called

  • GBS
  • Landry-Guillain-Barre syndrome
  • Guillain-Barre-Strohl syndrome
  • Idiopathic polyneuritis
  • Acute inflammatory polyneuropathy
  • Acute autoimmune neuropathy
  • Acute inflammatory demyelinating polyneuropathy (AIDP, the most common type of GBS).

Definitions

  • Prodromal phase - The phase during which an event, usually an infection, triggers a breakdown in the tolerance of the immune system followed by the initiation of an immune-mediated response.
  • Progressive phase - The phase during which neuropathy symptoms get progressively worse, may last days to up to 4 weeks, before symptoms plateau and then recede.,
  • Clinical nadir - The period of greatest disability or muscle weakness following the progressive phase, typically reached after 2 weeks.
  • Plateau phase - The period following clinical nadir where symptoms stay constant, typically lasting 1-4 weeks.
  • Recovery phase - The period where patients begin to recover from symptoms, which can last several months.
  • Mild GBS - Generally refers to being able to walk without assistance, but there is not a widely accepted definition (J Neurol Neurosurg Psychiatry 2017 Apr;88(4):346).

Types

  • See Clinical Presentation for details on clinical features of different types and variants of Guillain-Barre Syndrome (GBS). A short overview is presented below.
    • Acute inflammatory demyelinating polyradiculoneuropathy (AIDP) is the most common type. It is also called "typical GBS" or "classic sensorimotor GBS". It presents with rapidly progressive symmetric weakness, absent or reduced reflexes, and paraesthesias or sensory loss.
    • There are several less common variants of GBS.
      • Miller Fisher Syndrome (MFS) involves ophthalmoplegia, ataxia, and areflexia. Subtypes of MFS include:
        • MFS-GBS overlap syndrome (3 main features of MFS and also limb weakness and respiratory impairment)
        • Incomplete forms of MFS
        • Bickerstaff brainstem encephalitis (3 main features of MFS and also pyramidal tract signs and impaired consciousness)
      • Pure motor GBS does not involve sensory symptoms.
      • Paraparetic GBS involves paresis restricted to the legs.
      • Bilateral facial palsy with paraesthesias involves bilateral facial weakness, paraesthesias, and reduced reflexes.
      • Pharyngeal-cervical-brachial GBS involves pharyngeal, cervical, and brachial muscle weakness but not lower-limb weakness.
      • Pure sensory GBS involves sensory neuropathy without other deficits.
      • Acute motor axonal neuropathy (AMAN) and acute motor-sensory axonal neuropathy (AMSAN) are variants defined by electrodiagnostic study results.
  • STUDY SUMMARY
    distribution of types of Guillain-Barre Syndrome varies based on region
    COHORT STUDY: Brain 2018 Oct 1;141(10):2866

Epidemiology

Incidence/Prevalence

  • The reported lifetime risk of Guillain-Barre syndrome (GBS) is 0.1%. The reported annual incidence is 1-2 cases per 100,000 person-years.
  • STUDY SUMMARY
    incidence of GBS might be higher in winter than summer
    SYSTEMATIC REVIEW: J Neurol Neurosurg Psychiatry 2015 Nov;86(11):1196

Risk Factors

  • Incidences are higher in male individuals and older persons.
  • Preceding infection is the most common risk factor of GBS.
    • GBS incidence may increase during outbreaks of infectious organisms.
    • Prior infection is the most common reported cause of GBS; see Causes for details.
  • The following have been reported as potential risk factors for GBS, but evidence is limited: trauma, surgery, immune checkpoint inhibitors, other medications, and other systemic disorders or illnesses.

Vaccine-Related Considerations

    CLINICIANS' PRACTICE POINT

    Vaccination may have the potential to lead to Guillain-Barre syndrome (GBS) in a small minority of patients, but reports are rare, and evidence is conflicting and limited and should not be used to advise against vaccinations. However, if the patient has previously been diagnosed with GBS within 6 weeks of an influenza vaccination of any type and is not at high risk of severe influenza complications, consider avoiding future influenza vaccination.

  • Information on GBS and vaccines from the Centers for Disease Control and Prevention (CDC) can be found at CDC 2024 Jul.
  • Influenza vaccination is generally not recommended in persons with a history of GBS diagnosed within 6 weeks following a previous dose of any type of influenza vaccine who are not at high risk of severe influenza complications (Vaccine 2019 Sep 3;37(37):5544) (also see Seasonal Influenza Vaccination).
  • Epidemiological studies demonstrate there is either no association between GBS and most vaccines or that evidence is conflicting and limited, including:
    • Polio
    • Diphtheria tetanus toxoid pertussis
    • Measles/mumps/rubella (MMR)
    • Human papillomavirus (HPV)
    • Quadrivalent conjugated meningococcal
    • Influenza
    • Reference - Vaccine 2019 Sep 3;37(37):5544
  • STUDY SUMMARY
    pandemic and seasonal influenza vaccines might each be associated with an increased risk of GBS, but clinical implications are unclear
    SYSTEMATIC REVIEW: Vaccine 2015 Jul 17;33(31):3773

  • STUDY SUMMARY
    first dose of adenovirus vector COVID-19 vaccine (AstraZeneca) and mRNA COVID-19 vaccine (Pfizer-BioNTech) may each not be associated with increased risk of Guillain-Barre syndrome in adults in Spain and the United Kingdom
    COHORT STUDY: BMJ 2022 Mar 16;376:e068373

Etiology and Pathogenesis

Causes

  • Guillain-Barre Syndrome (GBS) is thought to be caused by an aberrant immune response that targets the peripheral nerves and their spinal roots.,
  • Infection is the most commonly identified precedent factor that may cause the immune response.
  • It is possible that some biological immunomodulatory medications, such as checkpoint inhibitors and anti-tumor necrosis factor alpha agents, might also cause an aberrant immune response and lead to GBS, but evidence is limited.
  • Immunogenetic factors may also play a role as GBS is a rarely acquired condition.

Pathogenesis

  • Some molecular structures of pathogens may be similar to molecular structures in cells of humans ("molecular mimicry"), and so targeted immune responses triggered by an infection may also end up damaging human cells. It is not clear why or how some persons are more susceptible to this.
  • Antibodies targeting particular gangliosides on neurons may be associated with particular variants of Guillain-Barre Syndrome (GBS). However, the clinical relevance of these potential associations is unclear.
    • Acute inflammatory demyelinating polyradiculoneuropathy (AIDP) may be associated with antibodies targeting LM1 and Gal-C.
    • Acute motor axonal neuropathy (AMAN) may be associated with antibodies targeting GM1, GM2, GD1b, GT1b, GM3, GD1a, and GalNac-GD1a.
    • Acute motor-sensory axonal neuropathy (AMSAN) may be associated with antibodies targeting GM1, GM1b, and GD1a.
    • Bickerstaff brainstem encephalitis may be associated with antibodies targeting GQ1b.
    • Miller Fisher Syndrome (MFS) may be associated with antibodies targeting GQ1b, GM1b, GT1a, GD3, and GD1c.
    • Pharyngeal-cervical-brachial variant may be associated with antibodies targeting GT1a, GQ1b, and GD1b.
    • Sensory ataxic variant may be associated with antibodies targeting GD1b.
  • In AIDP (the most common type of GBS), antibodies are thought to attack myelin and activate complement to form membrane attack complex on Schwann cells.
    • The resulting demyelination, particularly in proximal nerve roots and distal nerve segments (where the blood-nerve barrier is weak), impairs nerve conduction, leading to sensorimotor deficits.
    • The subsequent remyelination results in shorter internodes, leading to persistent conduction abnormalities in electrodiagnostic studies (even after clinical recovery).
  • In AMAN, antibodies are thought to attack nodal structures, ventral roots, and motor nerve terminals.
    • AMAN is associated with antibodies targeting GM1 and GD1a gangliosides, which are highly expressed in the nodes of Ranvier.
    • Damage to the nodes of Ranvier results in fewer functioning sodium channels and longer nodes. Damage to paranodal areas further impairs conduction.
    • The resulting muscle weakness can potentially be reversible with treatment, but delayed recovery and persistent deficits may occur if there is axonal degeneration.
  • MFS is associated with antibodies targeting the GQ1b ganglioside, which is mostly expressed in paranodal myelin, mostly in oculomotor nerves (III-IV and VI cranial nerves), dorsal root ganglia, and neuromuscular spindle fibers (Front Neurol 2023;14:1250774).
Possible immunopathogenesis of Guillain-Barre syndrome

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Possible immunopathogenesis of Guillain-Barre syndrome

(A) Antibody binding to myelin postulated to cause formation of a MAC leading to neural injury. Later macrophage scavenging causes removal of myelin debris. (B) Immunopathogenesis of acute motor axonal neuropathy form of Guillain-Barre syndrome. IgG anti-GM1 or anti-GD1a autoantibodies bind to nodal axolemma leading to MAC formation. This causes detachment of paranodal myelin which can lead to nerve-conduction failure and muscle weakness. Axonal degeneration may follow at a later stage. Abbreviations: IgG, immunoglobulin G; MAC, membrane-attack complex.

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Produced in collaboration with American College of Physicians
American College of Physicians

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