Psychiatric onset of multiple sclerosis

We present a patient with psychotic disorder as onset of relapsing–remitting multiple sclerosis (MS). In this patient, a 26-year-old female, neurological examination revealed only minor abnormalities. As cranial CT scan was normal, her psychosis was diagnosed as psychogenic. Literature on psychiatric onset of MS is reviewed paying special attention to clinical and MRI aspects. It is concluded that psychiatric onset of MS may occur in up to 1% of patients, and that in previously healthy persons with acute psychotic disorder even the slightest neurological abnormality justifies a cranial MRI examination.