Accepted for Publication: August 22, 2014.
Published Online: December 1, 2014. doi:10.1001/jamaneurol.2014.2956.
Study concept and design: Leypoldt, Titulaer, Rosenfeld, Dalmau.
Acquisition, analysis, or interpretation of data: Leypoldt, Höftberger, Titulaer, Armangue, Gresa-Arribas, Jahn, Rostasy, Schlumberger, Meyer, Wandinger, Graus, Dalmau.
Drafting of the manuscript: Leypoldt, Höftberger, Titulaer, Gresa-Arribas, Jahn, Schlumberger, Rosenfeld, Graus, Dalmau.
Critical revision of the manuscript for important intellectual content: Leypoldt, Titulaer, Armangue, Rostasy, Meyer, Wandinger, Rosenfeld, Dalmau.
Statistical analysis: Leypoldt, Titulaer, Dalmau.
Obtained funding: Leypoldt, Dalmau.
Administrative, technical, or material support: Armangue, Jahn, Meyer, Wandinger, Rosenfeld, Dalmau.
Study supervision: Graus, Dalmau.
Conflict of Interest Disclosures: Dr Leypoldt has received speakers honoraria and travel support from Grifols. Dr Titulaer has received travel support from Sun Pharma. Dr Schlumberger is an executive board member and shareholder of Euroimmun AG. Dr Meyer is a consultant to Spirig Pharma and has received speaker honoraria from Becton-Dickinson and Gilead. Dr Rosenfeld holds a patent for the use of N-methyl-D-aspartate receptor as an autoantibody test and receives royalties for antibody testing. Dr Dalmau received a research grant from Euroimmun and holds a patent application for the use of N-methyl-D-aspartate receptor as an autoantibody test; he receives royalties for this antibody testing. No other disclosures were reported.
Funding/Support: Dr Leypoldt was supported by Forschungsförderungsfonds Hamburg-Eppendorf. Dr Höftberger was partially funded by the Fonds zur Förderung der wissenschaftlichen Forschung, Austria, project J3230. Dr Titulaer was supported by an Erasmus MC fellowship and has received funding from the Netherlands Organisation for Scientific Research (NWO, Veni incentive). Dr Armangue has received a personal grant from the Instituto Carlos III (FI12/00366). Dr Gresa-Arribas has received funding from the Fundació la Marató de TV3. Dr Dalmau has received funding from the National Institutes of Health (grant RO1NS077851), Fundació la Marató TV3, and Fondo de Investigaciones Sanitarias (FIS, PI11/01780).
Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Additional Contributions: We thank Mercè Alba, Eva Caballero, and Esther Aguilar (August Pi i Sunyer Biomedical Research Institute [IDIBAPS], Service of Neurology, Hospital Clínic, University of Barcelona, Barcelona, Spain) for excellent technical support. They did not receive compensation from a funding sponsor for their contributions. We also thank the patients and their families for volunteering to participate in this study.