Late-onset schizophrenia with epileptiform discharge

We report the case of a 51-year-old woman with no history of psychosis or epilepsy, presenting with abrupt late-onset psychosis with prominent epileptiform discharges with a diffuse sharp and slow wave complex. She had auditory and somatic hallucinations, delusions and loosening of associations, but epileptic seizures such as disturbance of consciousness and convulsion were not observed. Other laboratory studies, including CT, magnetic resonance imaging, single photon emission computed tomography, and cerebrospinal fluid were normal. The epileptiform discharge disappeared within 10 days after starting treatment with sodium valproate. Clinical improvement commenced after the EEG improvement, and was complete. The cause remains obscure, but it was suggested that there were some organic factors in the etiology of this late-onset psychosis.