GAD1 and cerebellar ataxia: We retrospectively review prodromal symptoms in low-titer anti-GAD ataxia (section “Prodromal Stage in Patients with Anti-GAD Antibodies (José Fidel Baizabal-Carvallo)”), PCD (section “Prodromal Stage in PCD (Sergio Muñiz-Castrillo, Alberto Vogrig, Bastien Joubert, Jérôme Honnorat)”), gluten ataxia (GA) (section “Prodromal Stage in Gluten Ataxia (Marios Hadjivassiliou)”), and post-infectious cerebellar syndrome (section “Prodromal Stage in Post-infectious Cerebellar Syndrome (PiCS) (José Fidel Baizabal-Carvallo)”).