Treatment Approach for Conditions Requiring Intravenous Immunoglobulin (IVIG) Therapy
The recommended treatment approach for conditions requiring IVIG therapy should be tailored to the specific underlying condition, with treatment protocols varying based on disease pathophysiology, severity, and patient-specific factors. 1
Autoimmune Neurological Conditions
Autoimmune Encephalitis
- Initial therapy should include high-dose corticosteroids (methylprednisolone), with IVIG or plasma exchange (PLEX) added if there is no improvement 1
- For severe presentations, consider combination therapy with steroids plus IVIG or steroids plus PLEX from the beginning 1
- IVIG is preferred first in agitated patients and those with bleeding disorders 1
- PLEX is preferred first in patients with severe hyponatremia, high thromboembolic risk, or associated brain/spinal demyelination 1
- Standard IVIG dosing: 2 g/kg IV over 5 days (0.4 g/kg/day) 1
Guillain-Barré Syndrome
- For moderate to severe cases, IVIG (0.4 g/kg/day for 5 days for a total dose of 2 g/kg) or plasmapheresis is recommended 1
- Note that plasmapheresis immediately after IVIG will remove immunoglobulin and should be avoided 1
- Corticosteroids are not typically recommended for idiopathic GBS but may be considered in immune checkpoint inhibitor-related forms 1
Myasthenia Gravis
- For moderate to severe cases, IVIG 2 g/kg IV over 5 days or plasmapheresis for 3-5 days is recommended 1
- Consider rituximab if refractory to IVIG or plasmapheresis 1
- Pyridostigmine should be used concurrently for symptomatic management 1
Monoclonal Gammopathy-Related Disorders
Treatment Principles
- Treatment depends on severity - supportive care alone may be sufficient for mild symptoms 1
- For aggressive and disabling disease, therapy should target the underlying clone 1
- Treatment is only justified when there's a clear causal relationship between the monoclonal gammopathy and the associated disorder 1
IgM-Related Disease
- Rituximab monotherapy is recommended for conditions like anti-MAG polyneuropathy 1
- Consider adding chemotherapy to rituximab for severe symptoms requiring rapid tumor reduction 1
Non-IgM MGUS-Related Disorders
- Therapy should rely on antimyeloma agents 1
- For younger patients (≤65-70 years) with severe symptoms, consider high-dose melphalan with autologous stem cell transplantation 1
- Lenalidomide-based regimens are preferred for patients with neuropathy 1
- Bortezomib has highest efficacy in monoclonal protein-associated renal disorders 1
Immunoglobulin Replacement Therapy
Dosing for Primary Immunodeficiency
- For patients switching from IVIG to subcutaneous immunoglobulin (SCIG): Calculate initial weekly dose by converting monthly IVIG dose to weekly equivalent and multiplying by 1.37 2
- For treatment-naïve patients: Loading doses of 150 mg/kg/day for 5 consecutive days, followed by weekly administrations of 150 mg/kg/week 2
- Monitor IgG trough levels frequently (every 2 weeks) during first 8 weeks 2
Administration Considerations
- SCIG can be administered at intervals from daily up to every two weeks 2
- Maximum infusion volumes and rates vary by age:
- Children 2 to <10 years: 25 mL/site at ≤25 mL/hr/site
- Adults and children ≥10 years: 25 mL/site at ≤35 mL/hr/site 2
- Up to 6 infusion sites can be used simultaneously, with at least 2 inches between sites 2
Special Considerations
Monitoring During Treatment
- Monitor IgG levels regularly during treatment 3
- If immunoglobulin replacement therapy is initiated, monthly monitoring of Ig levels is recommended 3
- Consider immunoglobulin replacement therapy for patients who have experienced ≥2 severe recurrent infections by encapsulated bacteria 3
Adverse Effects Management
- Major adverse effects include thrombosis, renal impairment, aseptic meningitis, hemolysis, and transfusion-related acute lung injury 2, 4
- Risk factors for thrombosis include advanced age, immobilization, hypercoagulable conditions, history of thrombosis, estrogen use, and cardiovascular risk factors 2
- Ensure adequate hydration before administration 2
- For patients at risk of thrombosis, administer at minimum dose and infusion rate practicable 2
- Most adverse effects are transient and mild (flushing, headache, malaise, fever, chills) 4
Contraindications
- Anaphylactic or severe systemic reactions to human immunoglobulin or inactive ingredients 2
- IgA deficient patients with antibodies against IgA and history of hypersensitivity 2, 5
Disease-Specific Protocols
Anti-GBM Disease
- Initiate immunosuppression with cyclophosphamide and corticosteroids plus plasmapheresis 1
- Start treatment without delay once diagnosis is confirmed 1
- If diagnosis is highly suspected, begin high-dose corticosteroids and plasmapheresis while waiting for confirmation 1
- No maintenance immunosuppressive therapy is recommended 1
Clostridium difficile Infection
- IVIG should only be used as adjunct therapy in patients with multiple recurrent or fulminant CDI 1
- Consider IVIG therapy in patients diagnosed with hypogammaglobulinemia 1