In a retrospective case series, 12 MOG-IgG positive relapsing patients receiving monthly IVIG experienced an improvement of ARR from 2.16 to 0.51 (78) In addition, a case report of a child previously diagnosed with MS and subsequently found to be MOG-IgG positive was treated with multiple therapies with ongoing breakthrough disease, including interferon and rituximab, received IVIG as monotherapy on a monthly basis for 24 months with excellent disease control (98). The gene discussed is MOG; the disease is myeloid sarcoma.