Nine-Year Follow-Up of GAD65 Antibody Limbic Encephalitis With Clinical Remission Despite Persistent Imaging and Serological Abnormalities.

Glutamic acid decarboxylase 65 (GAD65) antibody-associated autoimmune encephalitis is a rare neurological disorder characterized by cognitive impairment, seizures, and psychiatric manifestations. Long-term outcomes and management strategies for this condition remain poorly documented in the medical literature. We present a nine-year follow-up of a young woman with GAD65 antibody-positive autoimmune limbic encephalitis who achieved complete clinical remission following aggressive immunomodulatory therapy. The patient, initially treated with rituximab, intravenous immunoglobulin (IVIG), and mycophenolate, successfully discontinued all immunosuppressive medications except hydroxychloroquine. She remains clinically asymptomatic with no recurrence of olfactory hallucinations or other neurological deficits, despite persistently elevated serum GAD65 antibody levels and persistent signal abnormalities on brain imaging. This case highlights the potential for favorable long-term outcomes in GAD65 antibody-associated encephalitis with appropriate immunotherapy and provides insights into maintenance therapy and medication withdrawal strategies for patients planning pregnancy.