Should a psychotic or manic episode be considered an early manifestation of Multiple Sclerosis? A multiple case study

•Early manifestations of multiple sclerosis (MS) are sometimes atypical or misleading.•Psychotic or manic disorders can reveal multiple sclerosis onset.•Psychotic/manic episodes should sometimes be considered an early manifestation of MS.

BackgroundEarly manifestations of Multiple Sclerosis (MS) can be atypical and misleading, and several case report studies have highlighted that MS onset sometimes takes the form of a psychotic or manic episode.MethodsAll neurologists belonging to the French Multiple Sclerosis Observatory network were contacted by email and were asked to find patients with MS who presented with a history of psychiatric episode(s) near MS onset.ResultsSeventeen patients were selected that met the criteria of presenting with psychotic or manic symptoms either before the diagnosis of MS (N=8), or at the time of the first neurological episode or shortly after (N=9). Patients with a history of a psychiatric episode occurring before the first neurological episode were diagnosed on average 7 years later than patients with either a first neurological or a mixed (both neurological and psychiatric) episode. However, psychiatric symptoms in the first group and the first neurological symptoms of MS in the second group occurred at a similar age.ConclusionBased on this multiple case study, we question whether past psychotic or manic episode should be considered equivalent to a first manifestation of MS.