[An acute psychotic episode revealing neuropsychiatric lupus with atypical brain MRI]

The frequency of neuropsychiatric symptoms in systemic lupus varies between 14 and 75%. Their mechanisms are multiple and their non-specificity makes the etiological diagnosis more difficult. The MRI lesions are dominated by small white matter hyperintensities.

We report a case of 17-year-old girl without medical, surgical or familial past, who presented an acute psychotic episode with fever. The neurological examination showed a pyramidal syndrome. The brain MRI objectified diffuse, bilateral and symmetrical white and gray matter hyperintensities. The diagnosis of neuropsychiatric lupus was retained with association of more than four criteria among the 11 ARA revised criteria: pleural effusion, neuropsychiatric manifestations, anemia, lymphopenia and positive ANA. The treatment was based on corticosteroids. The evolution was fatal.

Psychiatric disorders are polymorphic and appear during the course of the disease or at diagnosis; they can be seen in 20% of cases and are a sign of a poor prognosis. Most often these disorders are a non-specific reaction, but severe clinical forms can be observed as suicidal risk or mood disorders (depression, mania...), or acute psychotic episode.

The diagnosis of neuropsychiatric lupus must be evoked systematically in atypical neuropsychiatric disorders especially when confronted with minimal biological and brain imaging abnormalities.