Autoimmune “Atypical” Atypical Parkinsonism: Anti‐ <scp> GABA _B </scp> Receptor Encephalitis Presenting as a Reversible Mimic of Progressive Supranuclear Palsy

Ethical Compliance Statement: The authors confirm that the approval of an institutional review board was not required for this work. The authors obtained written consent from the patient. We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this work is consistent with those guidelines. Funding Sources and Conflicts of Interest: The authors report no source of funding. The authors report no conflicts of interest. Financial Disclosures for previous 12 months: The authors declare that there are no additional disclosures to report. The data that support the findings of this study are available from the corresponding author upon reasonable request. TABLE S1. Review of case reports and series showing immune mediated parkinsonism with antibody positivity. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.