Guillain-Barré syndrome: recognising ascending paralysis in general practice

What Guillain-Barré syndrome is

Guillain-Barré syndrome is a neurological emergency. It is an acute immune-mediated polyradiculoneuropathy — an autoimmune attack on the peripheral nervous system, typically triggered by a preceding infection — that produces rapidly progressive symmetrical ascending weakness, loss of reflexes, and frequent autonomic and respiratory failure. By definition the weakness reaches its nadir within 4 weeks; in most patients the peak disability occurs within 2 weeks of symptom onset.

Incidence in Australia is approximately 1.5–2 per 100,000 people per year, consistent with international rates per the Sejvar Neuroepidemiology 2011 systematic review and data from the GBS/CIDP Foundation Australia. Approximately 60–70% of patients report an antecedent illness 1–4 weeks before neurological onset. The condition affects both sexes, with a slight male predominance, and incidence increases with age beyond 50.

The GP role is: recognise, transfer, and later coordinate rehabilitation and re-vaccination counselling. There is no GP-level treatment available.

A. Core clinical — the AU general-practice framework

GBS subtypes

Subtype	Pathology	Frequency (Western)	Key associations
AIDP	Demyelinating; peripheral myelin attack	~85%	Classic ascending paralysis
AMAN	Axonal; motor axon attack	~5–10%	Campylobacter jejuni, anti-GM1/GD1a
AMSAN	Axonal; motor + sensory	<5%	Severe; slower recovery
Miller Fisher syndrome	Demyelinating + anti-GQ1b	~5%	Ophthalmoplegia, ataxia, areflexia
Pharyngeal-cervical-brachial	Variant	<5%	Bulbar + upper limb predominant

Antecedent infections

Approximately 60–70% of GBS cases are preceded by an infection 1–4 weeks earlier:

• Campylobacter jejuni — the most common identifiable trigger (~25–40%); diarrhoeal illness; molecular mimicry between lipopolysaccharide ganglioside epitopes and peripheral nerve antigens; strongly linked to AMAN subtype
• CMV — second most common; tends to produce severe sensory involvement
• EBV, Mycoplasma pneumoniae, Haemophilus influenzae, VZV, HEV — less common
• SARS-CoV-2 — associated GBS cases reported throughout the pandemic; Keddie Brain 2021 confirmed an excess incidence in the UK COVID-19 cohort, predominantly AIDP subtype
• Post-vaccination GBS — rare; approximately 1 excess case per million inactivated influenza vaccine doses; elevated risk reported after Ad26.COV2.S COVID-19 vaccine; ATAGI guides management of future vaccination after GBS

Clinical presentation

The typical presentation is:

1. Distal paraesthesia — tingling or numbness starting in feet and/or hands; often the first symptom, appearing 1–2 days before weakness
2. Symmetrical ascending weakness — beginning in the distal lower limbs and ascending proximally; difficulty climbing stairs, rising from a chair, or lifting objects
3. Areflexia — loss of tendon reflexes is universal at nadir and usually appears early; absent ankle jerks in an acutely weak patient should raise immediate suspicion
4. Back pain — often reported and caused by nerve root inflammation; can mislead towards a musculoskeletal or disc diagnosis
5. Facial weakness — bilateral facial palsy in approximately 50%
6. Bulbar weakness — dysphagia and dysarthria; risk of aspiration
7. Autonomic instability — labile blood pressure, arrhythmia (particularly bradycardia), urinary retention, and ileus in approximately two-thirds
8. Respiratory failure — in approximately 30% of patients; can be precipitous

The 20/30/40 rule for respiratory risk

The three-criterion bedside test for impending ventilatory failure:

• Forced vital capacity (FVC) < 20 mL/kg → high intubation risk
• Maximum inspiratory pressure (MIP) more negative than −30 cmH₂O → high risk
• Maximum expiratory pressure (MEP) below +40 cmH₂O → high risk

Any one criterion positive indicates the need for ICU monitoring. Two or three positive criteria indicate that intubation is likely within hours. The EGRIS score (Erasmus GBS Respiratory Insufficiency Score) — calculated at admission using days from onset, facial/bulbar weakness, and arm weakness — provides a validated prediction of ventilation need.

B. Diagnosis and investigations

Brighton criteria

The Brighton Collaboration criteria (Fokke Brain 2014) classify diagnostic certainty into four levels. Level 1 (highest certainty) requires all three of:

1. Bilateral flaccid limb weakness (ascending)
2. Diminished or absent tendon reflexes in the weak limbs
3. Monophasic illness with nadir reached between 12 hours and 28 days, followed by a plateau

Nerve conduction studies and CSF albuminocytological dissociation (raised protein, normal cell count) are supporting criteria — not required for a Level 1 clinical diagnosis.

Investigations in the GP setting

In the pre-transfer period, the following investigations are appropriate if they do not delay transfer:

• Urinalysis and BSL — exclude metabolic causes of weakness
• FBC, UEC, LFT, CRP — baseline and to exclude metabolic cause
• Campylobacter stool PCR or culture — if antecedent diarrhoeal illness (does not change acute management but informs epidemiology)

Do not delay ambulance transfer to await investigation results.

Investigations performed in hospital

• CSF analysis — albuminocytological dissociation present in approximately 50% at Day 1, rising to 80% by Day 7; used to support diagnosis; normal CSF does not exclude GBS early in the illness
• Nerve conduction studies (NCS) — distinguish demyelinating (AIDP) from axonal (AMAN/AMSAN) variants; typically performed within 48–72 hours of admission
• Anti-GQ1b antibodies — for Miller Fisher syndrome or Bickerstaff brainstem encephalitis (anti-GQ1b positive in ~85% of MFS)
• Respiratory function — serial spirometry (FVC, MIP, MEP) 4–6 hourly; the primary monitoring tool for respiratory deterioration

C. Treatment

IVIg and plasma exchange

Hughes et al. Cochrane 2014 established that IVIg 2 g/kg over 5 days and plasma exchange (PLEX) 5 sessions over 2 weeks are equivalent in efficacy for GBS — both shorten time to walking and reduce the proportion requiring mechanical ventilation. Neither is superior; selection depends on local availability, patient preference, contraindications (IVIg: renal failure with IgA deficiency, thromboembolic risk; PLEX: haemodynamic instability, sepsis, lack of venous access), and the National Blood Authority BloodSafe criteria for IVIg approval.

A second course of IVIg is not routinely recommended — randomised evidence (SID-GBS trial) found no benefit of a second 2 g/kg dose over placebo in patients not improving after the first course.

Corticosteroids — not recommended

Corticosteroids have no benefit in GBS and are not recommended. Hughes Cochrane 2016 confirmed this for both oral and IV steroids, with no improvement in any primary outcome including time to walk unaided, disability grade, or pain scores. The counterintuitive finding is well-established; do not administer corticosteroids for GBS.

Supportive care in hospital

• Serial spirometry (FVC 4–6 hourly) with pre-defined intubation thresholds
• Continuous cardiac monitoring for autonomic arrhythmia — bradycardia from vagal hyperactivation is particularly hazardous
• DVT prophylaxis — subcutaneous heparin plus compression stockings; GBS patients are at high PE risk from immobility
• Neuropathic pain — gabapentin or pregabalin; opioids for breakthrough pain; do not delay adequate analgesia as pain is often severe
• Physiotherapy commenced once medically stable — early rehabilitation prevents contractures and facilitates walking recovery
• Nutritional support — nasogastric feeding if dysphagia is present; aspiration precautions

Outcomes

• ~80% walk unaided at 6 months
• ~5% in-hospital mortality (respiratory failure, autonomic instability, PE, sepsis)
• ~20% have significant residual disability at 1 year — ongoing sensory symptoms, fatigue, and neuropathic pain are particularly common and disabling

D. Australian operations

Transfer and retrieval

Any patient suspected of GBS with progressive weakness — particularly if unable to walk without assistance, or with facial/bulbar involvement — should be transferred by ambulance to the nearest hospital with ICU capability and neurological services. Rural and remote patients are retrieved via the state aeromedical retrieval service; contact the relevant state retrieval coordination service.

National Blood Authority — IVIg approval

IVIg for GBS requires National Blood Authority (NBA) BloodSafe approval in Australian hospitals. GBS with inability to walk unaided within 2–4 weeks of onset is a standard listed indication. The prescribing clinician (neurologist or intensivist) initiates the request. GPs are not the authorising prescriber but should document the clinical presentation clearly in the transfer letter to facilitate timely approval.

MBS and PBS

• MBS 11005/11010 — nerve conduction studies and electromyography for diagnosis
• MBS 65070 — CSF examination when differential includes GBS
• IVIg — funded through the National Blood Authority via public hospitals under standing criteria; not PBS-listed for outpatient use
• Plasma exchange — performed in tertiary centres with apheresis units (major public hospitals in each capital city)

Post-discharge GP care

• Fatigue management — one of the most disabling residual symptoms; pacing strategies and occupational therapy referral
• Neuropathic pain — ongoing gabapentin, pregabalin, or duloxetine as needed; review duration and dose at each GP visit
• Depression and anxiety — common in prolonged recovery; screen and treat; refer to psychology as needed
• Driving and work — Austroads fitness to drive standards require functional assessment before return to driving; private vehicle return requires neurological clearance; commercial vehicle standards are stricter
• Re-vaccination counselling — see Section E below

Campylobacter notification

Campylobacter is a notifiable disease in all Australian states and territories. If confirmed as the antecedent trigger, notify the relevant state public health unit. This has epidemiological rather than clinical management implications for the GBS patient.

E. Special populations

Post-COVID GBS

SARS-CoV-2-associated GBS has been documented across multiple international cohorts. Keddie Brain 2021 reported a UK cohort of 47 patients with a predominant AIDP phenotype, with onset typically 11–25 days after COVID-19 symptom onset. The absolute excess risk is low. Management is identical to non-COVID GBS. COVID-19 vaccination is not contraindicated after recovery from COVID-19 GBS — the association is with infection, not the vaccine.

Post-vaccination GBS

ATAGI recommends case-by-case assessment for future vaccination after any episode of GBS, balancing the ongoing risk of vaccine-preventable infection against a theoretical re-occurrence risk. Most patients who have had GBS — including post-vaccination GBS — can be safely revaccinated after full neurological recovery and specialist neurological assessment. The absolute risk of GBS recurrence with vaccination is very low and must be weighed against the substantially higher risk of serious illness from influenza or other vaccine-preventable diseases.

Pregnancy and GBS

GBS can occur during pregnancy or the post-partum period. The clinical presentation and treatment principles are identical to non-pregnant patients — IVIg is safe in pregnancy; PLEX is technically more challenging but feasible with experienced apheresis teams. Respiratory failure in a third-trimester pregnancy is a particularly complex scenario requiring close collaboration between neurology, obstetrics, and intensive care. Neonatal outcomes are generally good if the mother is stabilised.

Older adults

Older adults with GBS have slower and less complete recovery than younger patients. The EGRIS score may underestimate ventilation risk in older adults because baseline respiratory reserve is lower. Advance care planning discussions about ventilatory support should occur early after diagnosis — ideally before transfer — particularly in patients with pre-existing respiratory or cardiac disease. The treating team leads this discussion with the patient and family.

When to escalate

• Any patient with progressive symmetrical limb weakness plus areflexia → call 000; ambulance transfer to hospital with ICU capability today
• Rapid progression — unable to walk independently, or developing facial weakness, dysphagia, or shortness of breath → do not wait; same-day emergency transfer
• Atypical presentation — asymmetric weakness, predominantly sensory without weakness, or ophthalmoplegia with ataxia (Miller Fisher) → still transfer urgently; do not wait for diagnostic certainty
• Back pain plus new limb weakness → do not assume musculoskeletal cause; GBS must be excluded with neurological assessment
• Post-discharge worsening — a minority of patients have treatment-related fluctuations or relapse; urgent neurology re-referral if weakness worsens after initial improvement

What this article is and is not

This article provides a general-practice recognition and referral framework for Guillain-Barré syndrome in Australia, drawing on Hughes Cochrane IVIg (2014) and steroids (2016), Brighton criteria (Fokke Brain 2014), EGRIS (Walgaard Ann Neurol 2010), ATAGI guidance, National Blood Authority BloodSafe criteria, and Therapeutic Guidelines (eTG). It does not replace specialist neurology, intensive care, or rehabilitation medicine advice. All treatment decisions — IVIg dose, plasma exchange, ventilation thresholds — are made by the treating specialist team. Nothing in this article constitutes clinical advice for any individual patient.

For patient and family support: GBS/CIDP Foundation Australia.

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Sources cited

1. Hughes RAC et al. Intravenous immunoglobulin for Guillain-Barré syndrome. Cochrane Database Syst Rev 2014
2. Hughes RAC et al. Corticosteroids for Guillain-Barré syndrome. Cochrane Database Syst Rev 2016
3. Fokke C et al. Diagnosis of Guillain-Barré syndrome and validation of Brighton criteria. Brain 2014;137:33
4. Walgaard C et al. Prediction of respiratory insufficiency in Guillain-Barré syndrome (EGRIS). Ann Neurol 2010;67:781
5. Keddie S et al. Epidemiological and cohort study of SARS-CoV-2 associated Guillain-Barré syndrome. Brain 2021;144:682
6. Sejvar JJ et al. Population incidence of Guillain-Barré syndrome. Neuroepidemiology 2011;36:123
7. ATAGI — Clinical guidance on COVID-19 vaccine safety monitoring
8. National Blood Authority — BloodSafe: IVIg criteria for neurological conditions
9. GBS/CIDP Foundation Australia
10. eTG complete — Guillain-Barré syndrome
11. RACGP — Neurological emergencies in general practice