Authors: Kirkham FJ, Haywood P, Kaypashe P, Borbone J, Lording A, Pryde K, Cox M, Keslake J, Smith M, Cuthbertson L, Murugan V, Mackie S, Thomas NH, Whitney A, Forrest KM, Parker A, Forsyth R, Kipps CM Abstract The literature on paediatric acute-onset movement disorders is scattered. In a prospective cohort of 52 children (21 male; age range 2mo-15y), the commonest were chorea, dystonia, tremor, myoclonus, and Parkinsonism in descending order of frequency. In this series of mainly previously well children with cryptogenic acute movement disorders, three groups were recognised: (1) Psychogenic disorders (n = 12), typically >10 years of age, more likely to be female and to have tremor and myoclonus (2) Inflammatory or autoimmune disorders (n = 22), including N-methyl-d-aspart...