Abstract
BACKGROUND AND PURPOSE: Population-based studies suggest severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines may trigger neurological autoimmunity including immune-mediated thrombotic thrombocytopenia. Long-term characterization of cases is warranted to facilitate patient care and inform vaccine-hesitant individuals. METHODS: In this single-center prospective case study with a median follow-up of 387 days long-term clinical, laboratory and imaging characteristics of patients with neurological autoimmunity diagnosed in temporal association (≤6 weeks) with SARS-CoV-2 vaccinations are reported. RESULTS: Follow-up data were available for 20 cases (central nervous system demyelinating diseases n = 8, inflammatory peripheral neuropathies n = 4, vaccine-induced immune thrombotic thrombocytopenia n = 3, myositis n = 2, myasthenia n = 1, limbic encephalitis n = 1, giant cell arteritis n = 1). Following therapy, the overall disability level improved (median modified Rankin Scale at diagnosis 3 vs. 1 at follow-up). The condition of two patients worsened despite immunosuppressants possibly related to their autoimmune diagnoses (limbic encephalitis n = 1, giant cell arteritis n = 1). At 12 months' follow-up, 12 patients achieved complete clinical remissions with partial responses in five and stable disease in one case. Correspondingly, autoimmune antibodies were non-detectable or titers had significantly lowered in all, and repeat imaging revealed radiological responses in most cases. Under vigilant monitoring 15 patients from our cohort underwent additional SARS-CoV-2 vaccinations (BNT162b2 n = 12, mRNA-1273 n = 3). Most patients (n = 11) received different vaccines than prior to diagnosis of neurological autoimmunity. Except for one short-lasting relapse, which responded well to steroids, re-vaccinations were well tolerated. CONCLUSIONS: In this study long-term characteristics of neurological autoimmunity encountered after SARS-CoV-2 vaccinations are defined. Outcome was favorable in most cases. Re-vaccinations were well tolerated and should be considered on an individual risk/benefit analysis.