Increased proportion of CD20+ T cells after rituximab treatment in patient with neuromyelitis optica later diagnosed with lung B-cell lymphoma: A case report

Introduction: Neuromyelitis optica (NMO) is a rare inflammatory autoimmune disorder of the CNS. Rituximab is used to treat antibody-mediated autoimmune diseases. Case presentation: We report the case a patient with NMO, who was treated with rituximab and presented CD20+ T cells by flow cytometry after treatment, later diagnosed with lung B-cell lymphoma. Conclusion: This is the first report of CD20+ T cell detection in an NMO patient. We found that CD20+ T cells recovered faster than B cells after rituximab treatment and that CD20+ T cells seemed to play a role in suppressing tumor growth and memory T cell activity.