What is the recommended treatment for a patient with Acute Inflammatory Demyelinating Polyneuropathy (AIDP), also known as Guillain-Barré Syndrome?

Treatment of Acute Inflammatory Demyelinating Polyneuropathy (AIDP/Guillain-Barré Syndrome)

For patients with AIDP presenting with moderate to severe symptoms (grade 2-4), initiate intravenous immunoglobulin (IVIg) at 0.4 g/kg/day for 5 consecutive days (total dose 2 g/kg) as first-line treatment, with plasmapheresis as an equally effective alternative. 1, 2

Severity Assessment and Treatment Initiation

Grade 2 (Moderate):

• Symptoms include moderate interference with activities of daily living, symptoms concerning to patient 3
• Discontinue immune checkpoint inhibitors if applicable 3
• Obtain immediate neurology consultation 3

Grade 3-4 (Severe):

• Limiting self-care, weakness limiting walking, ANY dysphagia, facial weakness, respiratory muscle weakness, or rapidly progressive symptoms 3
• Admit to inpatient unit with capability for rapid ICU transfer 3
• Initiate treatment immediately given risk of respiratory failure 1, 2

First-Line Immunotherapy

IVIg is the preferred first-line treatment:

• Dosing: 0.4 g/kg/day for 5 consecutive days (total 2 g/kg) 3, 1, 2
• IVIg is particularly effective in the AIDP subtype, with significantly better outcomes at 6 months compared to natural course 4
• Easier to administer than plasmapheresis and better tolerated in many patients 5

Plasmapheresis as alternative:

• 5 sessions at 200-250 mL/kg, equally effective to IVIg 1, 6
• Critical caveat: Do not perform plasmapheresis immediately after IVIg as it will remove the immunoglobulin 3
• Consider if IVIg is unavailable or contraindicated 1

Role of Corticosteroids

Corticosteroids alone are NOT recommended for idiopathic GBS as they have shown no significant benefit 2, 6. However, in immune checkpoint inhibitor-related AIDP, a trial of corticosteroids is reasonable:

• Methylprednisolone 2-4 mg/kg/day, followed by slow taper 3
• Pulse dosing (methylprednisolone 1 g daily for 5 days) may be considered for grade 3-4 along with IVIg or plasmapheresis 3
• Taper should begin 3-4 weeks after initiation 3

Critical Monitoring Requirements

Respiratory monitoring using the "20/30/40 rule":

• Vital capacity <20 mL/kg, maximum inspiratory pressure <30 cmH₂O, or maximum expiratory pressure <40 cmH₂O indicates high risk of respiratory failure 1, 2
• Up to 30% of patients develop respiratory failure requiring mechanical ventilation 2, 7
• Perform frequent pulmonary function testing 3

Neurologic monitoring:

• Daily neurologic examinations to assess progression 3
• Monitor for autonomic dysfunction (blood pressure, heart rate, bowel/bladder function) 3, 2
• Assess swallowing and coughing to prevent aspiration 2

Medications to Avoid

Avoid drugs that worsen neuromuscular function:

• β-blockers, IV magnesium, fluoroquinolones, aminoglycosides, and macrolides 3, 1
• These can exacerbate weakness and prolong recovery 1

Diagnostic Workup

Essential diagnostic studies:

• Neurology consultation 3, 2
• MRI spine with or without contrast to rule out compressive lesions and evaluate nerve root enhancement 3, 2
• Lumbar puncture: CSF typically shows elevated protein with normal or mildly elevated WBCs (albuminocytologic dissociation) 3, 2
• Serum antiganglioside antibody tests (e.g., anti-GQ1b for Miller Fisher variant) 3, 2
• Electrodiagnostic studies (nerve conduction studies and EMG) to evaluate polyneuropathy 3, 2

Treatment-Related Fluctuations

About 6-10% of patients experience secondary deterioration within 2 months:

• Treatment-related fluctuations require repeat IVIg courses 2, 6
• May require multiple rounds of immunotherapy 3
• Monitor closely during first 8 weeks after initial treatment 6

Supportive Care

Pain management:

• Use nonopioid management of neuropathic pain: pregabalin, gabapentin, or duloxetine 3
• Pain is common and may precede weakness, potentially confusing diagnosis 6

Additional supportive measures:

• Treatment of constipation/ileus 3
• Multidisciplinary care including physiotherapy, occupational therapy, and speech therapy 2
• Prevention of complications: pressure ulcers, hospital-acquired infections, deep vein thrombosis 2

Prognosis

Expected outcomes:

• About 80% of patients regain walking ability at 6 months 1
• About 40% show no improvement in the first 4 weeks, which does not indicate treatment failure 1, 2
• Mortality rate is 3-10%, primarily due to cardiovascular and respiratory complications 1, 6
• About 20% remain unable to walk at 6 months despite treatment 6
• Two-thirds of deaths occur during the recovery phase due to cardiovascular and respiratory dysfunction 2