Evaluation of Responsiveness to Reduced-Dose Rituximab in Corticotropin/Intravenous Immunoglobulin/Rituximab Combination Immunotherapy for Opsoclonus-Myoclonus Syndrome.

Background: Rituximab (anti-CD20) has been used as B-cell-targeted intervention to treat opsoclonus-myoclonus syndrome. Due to isolated reports of chronic hypogammaglobulinemia and B lymphopenia following rituximab in several disorders, and rapid B-cell depletion after a few doses, we reduced the dosage 20% in our clinical practice.

Methods: In this Institutional Review Board-approved retrospective study, 32 children with opsoclonus-myoclonus syndrome and cerebrospinal fluid B-cell expansion had received front-loaded adrenocorticotropic hormone, intravenous immunoglobulin, and rituximab combination immunotherapy for de novo opsoclonus-myoclonus syndrome.