Autoimmune Cerebellitis

This is a multicenter, single-arm, continuous, prospective, interventional registry study designed to systematically evaluate the efficacy and safety of low-dose blinatumomab in patients with antibody-mediated refractory autoimmune encephalitis (AE) and autoimmune cerebellitis. Eligible participants will be patients with a confirmed diagnosis of refractory AE or autoimmune cerebellitis who have provided written informed consent. All enrolled patients will receive blinatumomab treatment according to a unified protocol, consisting of two cycles: Cycle 1 (Week 1): Continuous intravenous infusion at 9 µg/day for 5 consecutive days (total dose: 45 µg). Cycle 2 (Week 3): Continuous intravenous infusion at 9 µg/day for 5 consecutive days (total dose: 45 µg). If there is no improvement in the modified Rankin Scale (mRS) score at Week 3 and the proportion of peripheral blood B cells (CD3-/CD19+) remains \>1%, the dose may be optimized to 15 µg/m²/day (maximum 28 µg/day). During the study, all patients will undergo regular follow-up visits to collect data on clinical symptoms, functional scores, immunological biomarkers, and adverse events, to comprehensively assess the efficacy and safety of the treatment. This study uses a non-randomized, open-label design with no blinding or control group.