Can Varicella Cause Guillain-Barré Syndrome?
Yes, varicella-zoster virus (VZV) infection can cause Guillain-Barré syndrome (GBS), though it is a rare trigger, and clinicians should maintain awareness of this association particularly when patients develop ascending weakness following chickenpox or shingles.
Evidence for the Association
While the major GBS guidelines 1 establish that GBS is typically triggered by infections and note specific outbreaks (like Zika virus), they do not specifically list varicella as a common trigger. However, multiple case series and reports provide clear evidence of this association:
Primary Varicella (Chickenpox)
- In a large Bangladeshi cohort of 536 GBS patients, 7 (1.3%) developed GBS within 4 weeks of chickenpox 2
- All 7 cases showed the demyelinating subtype (AIDP pattern) on nerve conduction studies
- All had positive anti-VZV IgM antibodies and negative anti-GM1 antibodies
- Importantly, all patients achieved excellent outcomes at 1 year (able to run) 2
- A systematic literature review identified 39 additional cases with comparable presentations, with 36 showing demyelinating features 2
Key Clinical Pattern
The VZV-associated GBS cases demonstrate:
- Typical latency period: 7-14 days between varicella infection and GBS onset 2, 3
- Predominantly demyelinating subtype (AIDP), which is distinct from the axonal forms more common in some regions 2
- Severe presentations possible: including quadriplegia, bulbar paralysis, respiratory failure requiring mechanical ventilation 2, 3
- Generally favorable prognosis with appropriate treatment 2, 4
Clinical Implications
Recognition
When a patient presents with ascending weakness following recent chickenpox or shingles:
- Maintain high suspicion for GBS even though this is a rare trigger
- Look for the classic GBS features: ascending sensorimotor weakness, areflexia, sensory symptoms
- Check for CSF albuminocytologic dissociation (elevated protein, normal cell count) 2
- Obtain nerve conduction studies expecting demyelinating pattern 2
- Test for anti-VZV IgM to confirm recent infection 2
Treatment Approach
Follow standard GBS treatment protocols regardless of the triggering infection 1:
- Intravenous immunoglobulin (IVIg) 0.4 g/kg daily for 5 days is typically first-line
- Plasma exchange is equally effective but IVIg is easier to administer and more widely available 1
- Monitor respiratory function closely as 20% of GBS patients develop respiratory failure 1
- All reported VZV-associated cases responded well to standard immunotherapy 2, 4
Important Caveats
- Rare but real: VZV is an uncommon GBS trigger compared to Campylobacter jejuni or other pathogens
- Both primary infection and reactivation (shingles) can trigger GBS 4, 5, 6
- Distinguish from other VZV neurological complications: VZV can also cause vasculopathy, myelitis, cranial neuropathies, and rhombencephalitis 7, 6, which may initially mimic GBS
- The mechanism appears related to immune-mediated Schwann cell attack rather than direct viral invasion 3
Vaccination Consideration
While the Shingrix vaccine has an FDA black-box warning regarding possible GBS risk 8, the natural VZV infection itself is a documented GBS trigger. This should be factored into risk-benefit discussions, particularly for seronegative adults from populations with lower childhood varicella exposure 3.