A 26-year-old man developed a catatonic state after his grandmother's death and the Great East Japan Earthquake. He was admitted to hospital because of the prolonged severe stupor. Electroencephalography (EEG) revealed focal (F3 electrode) and generalized epileptic abnormalities. He was administered antiepileptic agents and benzodiazepines, but his stupor did not improve in spite of a reduced frequency of epileptic EEG abnormalities. His clinical history did not suggest any psychotic disorders. Thereafter, extensive physical examinations were performed, but an organic cause of the stupor was not determined. For about two years, he was unable to intake food without tubal feeding, have a conversation, or move spontaneously. One day, a generalized tonic-clonic seizure (GTC) occurred spontaneously for the first time in his life, and then his stupor markedly improved. Thereafter, he could eat food spontaneously, have a fluent conversation, and move actively. After his condition had improved, we asked his parents about his developmental history, clinical history, and present state. According to clinical interviews including the use of PARS (Pervasive Developmental Disorders Autism Society Japan Rating Scale), DISCO(Diagnostic Interview for Social and Communication Disorders), and WAIS-III (Wechsler Adult Intelligence Scale-third edition), he was diagnosed with autistic spectrum disorder (ASD) and mild intellectual disability. It was considered that his stupor had occurred secondary to ASD. Wing et al. reported that catatonia occurred in about 17% of ASD adolescents and young adults as a later complication. It is possible that this case, without any psychotic disorders and with ASD that has been undiagnosed until young adult, progress to such a severe and prolonged catatonic state. We report this case to show that severe catatonia is possible in adolescents and young adults during the carry-over period in ASD patients.
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