[Dystonia 12: A rare and difficult diagnosis].

We report a case of dystonia 12, also called rapid-onset dystonia-parkinsonism, which occurred in a young 12-year-old boy. Type 12 dystonia is a genetic syndrome characterized by a pathogenic mutation on ATP1A3 gene encoding the subunit alpha 3 of Na-K-ATPase protein, resulting in neuronal dysfunctions. It remains a rare syndrome with less than 100 cases described in the literature. Its atypical presentation and its rarity may lead to a wandering diagnosis, even in some cases to a conversion hysteria diagnosis. Today, unfortunately, there is no effective treatment.