IVIG for Long-Segment Myelitis
For long-segment myelitis, permanently discontinue any immune checkpoint inhibitor, initiate high-dose methylprednisolone (1 g IV daily for 3-5 days), and strongly consider adding IVIG at 2 g/kg divided over 5 days (0.4 g/kg/day), particularly for grade 2 or higher severity. 1
Severity-Based Treatment Algorithm
Grade 1 (Mild symptoms, no functional interference)
- Permanently discontinue immune checkpoint inhibitor
- Methylprednisolone 2 mg/kg IV daily
- Close monitoring for progression 1
Grade 2-4 (Moderate to severe symptoms with functional impairment)
- Permanently discontinue immune checkpoint inhibitor
- High-dose pulse steroids: Methylprednisolone 1 g IV daily for 3-5 days
- Strongly consider IVIG 2 g/kg total dose over 5 days 1
- Alternative: Plasmapheresis if IVIG unavailable or contraindicated
IVIG Dosing Specifications
The standard IVIG regimen for transverse myelitis is:
- Total dose: 2 g/kg body weight
- Administration: 0.4 g/kg/day for 5 consecutive days 2, 1
- Infusion rate: Start at 0.01 mL/kg/min (0.5 mg/kg/min), increase to maximum 0.10 mL/kg/min (5 mg/kg/min) if tolerated 3
For patients with cardiac dysfunction or fluid concerns, the dose may be split over 2 days (1 g/kg per day) 4
Critical Workup Requirements
Before initiating treatment:
- Neurology consultation immediately
- MRI spine with thin axial cuts through affected segments, plus brain MRI
- Lumbar puncture: Cell count, protein, glucose, oligoclonal bands, viral PCRs, cytology, onconeural antibodies
- Serology: B12, HIV, RPR, ANA, Ro/La, TSH, aquaporin-4 IgG (to exclude NMOSD)
- Assess for urinary retention and constipation 1
Evidence Strength and Context
The recommendations for IVIG in transverse myelitis come primarily from ASCO guidelines for immune checkpoint inhibitor-related adverse events 1. While these guidelines specifically address immune-related myelitis, the treatment principles apply broadly to severe inflammatory myelitis of various etiologies.
Important distinction: The evidence base differs from Guillain-Barré syndrome, where IVIG and plasmapheresis are equally effective first-line treatments 5. For transverse myelitis, corticosteroids remain the primary treatment, with IVIG serving as an important adjunctive therapy for moderate-to-severe cases 1.
Special Populations and Considerations
MOG-Antibody Associated Disease
- IVIG may be particularly effective in MOG-associated myelitis 6, 7
- Consider short-interval reinfusion (less than 2 weeks) if inadequate response to initial course, rather than waiting the typical 3-4 weeks 7
- Persistent high MOG-IgG titers and intrathecal antibody production indicate higher disease activity requiring escalation 8
Systemic Lupus Erythematosus-Associated Myelitis
- IVIG combined with high-dose steroids can produce rapid improvement (within 1 week on imaging) 9
- Monthly IVIG maintenance for 6 months may be beneficial for sustained remission 9
Common Variable Immunodeficiency
- High-dose subcutaneous immunoglobulin (0.2 g/kg/week) can maintain remission in recurrent myelitis 10
Critical Safety Precautions
Before administering IVIG:
- Check serum IgA levels (IgA deficiency increases anaphylaxis risk) 11
- Ensure adequate hydration to prevent renal complications 3
- Monitor for thrombosis risk, especially in patients with advanced age, immobilization, hypercoagulable states, or cardiovascular risk factors 3
- Administer at minimum effective infusion rate in high-risk patients 3
Contraindications:
- History of anaphylaxis to human immunoglobulin
- IgA deficiency with anti-IgA antibodies 3
- Hereditary fructose intolerance (IVIG contains sorbitol) 3
Monitoring During Treatment
- Vital signs throughout infusion
- Renal function (BUN, creatinine, urine output) in at-risk patients
- Blood viscosity assessment for hyperviscosity risk
- Daily neurologic examination
- Pulmonary function if respiratory involvement present 2
Common Pitfall
Do not administer plasmapheresis immediately after IVIG, as it will remove the immunoglobulin 2. If both treatments are needed, give plasmapheresis first, then IVIG, or separate them by adequate time intervals.
Treatment Failure Response
If no improvement after initial IVIG course: