What is the primary treatment for Acute Inflammatory Demyelinating Polyradiculoneuropathy (AIDP), also known as Guillain-Barré Syndrome?

Treatment of Acute Inflammatory Demyelinating Polyradiculoneuropathy (AIDP)

The primary treatment for AIDP (Guillain-Barré syndrome) is either intravenous immunoglobulin (IVIg) at 0.4 g/kg/day for 5 consecutive days (total dose 2 g/kg) or plasma exchange (typically 5 sessions at 200-250 ml/kg), both of which are equally effective and should be initiated as early as possible in the disease course. 1, 2

First-Line Treatment Options

You have two equally effective choices for immunotherapy:

• IVIg is generally preferred as the first-line treatment because it is easier to administer, more widely available, and associated with fewer adverse effects compared to plasma exchange 1
• Plasma exchange is equally effective and may be preferred when cost is a major consideration, as it can be significantly less expensive than IVIg (though still costly) 1
• Treatment should begin immediately upon diagnosis, ideally within 2 weeks of symptom onset for IVIg or within 4 weeks for plasma exchange 1

Critical Management Considerations

Immediate Actions Required

• Admit all patients to an inpatient unit with capability for rapid transfer to ICU-level monitoring, as GBS can progress rapidly to respiratory failure 1
• Discontinue any immune checkpoint inhibitors if the patient is receiving cancer immunotherapy 1
• Obtain neurology consultation immediately for all suspected cases 1

Essential Monitoring

• Respiratory function assessment is critical, as up to 30% of patients develop respiratory failure requiring mechanical ventilation 2, 3
• Use the "20/30/40 rule" to assess risk: vital capacity <20 ml/kg, maximum inspiratory pressure <30 cmH₂O, or maximum expiratory pressure <40 cmH₂O indicates high risk of respiratory failure 2
• Frequent neurological checks to monitor progression of weakness 1
• Monitor for autonomic dysfunction affecting blood pressure, heart rate, and bowel/bladder function 1, 2

Role of Corticosteroids

Corticosteroids alone are NOT recommended for idiopathic GBS, as they have shown no significant benefit in randomized controlled trials 1, 2, 4. However, there is one important exception:

• For immune checkpoint inhibitor-related GBS, a trial of corticosteroids is reasonable (methylprednisolone 2-4 mg/kg/day), used concurrently with IVIg or plasma exchange 1
• Pulse steroid dosing (methylprednisolone 1 g daily for 5 days) may also be considered for severe cases (grade 3-4) along with IVIg or plasmapheresis 1

Diagnostic Workup Before Treatment

Complete these studies urgently but do not delay treatment while awaiting results:

• MRI of spine with or without contrast to rule out compressive lesions and evaluate for nerve root enhancement 1
• Lumbar puncture: CSF typically shows elevated protein with normal or mildly elevated white blood cells (albuminocytologic dissociation) 1, 2
• Electrodiagnostic studies (nerve conduction studies and EMG) to evaluate polyneuropathy 1
• Serum antiganglioside antibody tests for GBS subtypes (e.g., anti-GQ1b for Miller Fisher variant) 1
• Pulmonary function testing to establish baseline respiratory status 1, 2

Supportive Care and Complication Management

Pain Management

• Use nonopioid agents for neuropathic pain: gabapentin, pregabalin, or duloxetine 1, 4
• Pain is common and can be severe, requiring specific management strategies 2

Medications to Avoid

Avoid these medications that can worsen neuromuscular function:

• β-blockers
• IV magnesium
• Fluoroquinolones
• Aminoglycosides
• Macrolides 1, 4

Additional Supportive Measures

• Treatment of constipation/ileus, which is common in GBS patients 1, 4
• Multidisciplinary care including physiotherapy, occupational therapy, and speech therapy 2
• Prevention of complications such as pressure ulcers, deep vein thrombosis, and hospital-acquired infections 2

Treatment-Related Fluctuations

• 6-10% of patients experience treatment-related fluctuations within 2 months of initial improvement 2
• These patients may require repeat IVIg courses 1
• About 40% of patients do not show improvement in the first 4 weeks following treatment 2

Common Pitfalls to Avoid

1. Delaying treatment while awaiting complete diagnostic workup—start immunotherapy as soon as GBS is clinically suspected 1, 2
2. Using corticosteroids alone for idiopathic GBS, which is ineffective 2, 4, 5
3. Administering plasmapheresis immediately after IVIg, which will remove the immunoglobulin—if switching therapies, allow appropriate time between treatments 1
4. Underestimating respiratory risk—two-thirds of deaths occur during the recovery phase due to cardiovascular and respiratory dysfunction 2
5. Failing to monitor for autonomic dysfunction, which can cause life-threatening arrhythmias and blood pressure instability 1, 2

Prognosis Considerations

• Despite optimal treatment, approximately 25% of patients require mechanical ventilation, 20% remain unable to walk after 6 months, and 3-10% die 5
• Many patients experience persistent pain, fatigue, or other residual symptoms for months to years 5