There are many causes of cerebellar ataxia (CA) including neurodegeneration and autoimmunity. We detected antiseizure-related 6 homolog-like 2 (Sez6l2) antibody from the serum of a patient with subacute CA.1 In this study, we conducted an 11-year follow-up of a previously reported female (case 1)1 and reported two new cases (case 2 and case 3) of Sez6l2 antibody-positive CA in Japan (online supplemental table 1).
