Introduction: Neurological or psychiatric manifestations are frequent during systemic lupus erythematosus (SLE). When faced with acute psychiatric symptoms, it is important to envisage the possibility of an organic origin.
Observation: A 36 year-old woman consulted for motor deficiency of the right lower body and paresthesia of the left arm. She exhibited severe psychiatric disorders suggesting conversion hysteria, mania, paranoia and acute psychosis. The existence of an acute delusional disorder, associated with an episode of articular lupus 7 years earlier, led to the diagnosis of SLE.
Discussion: The physiopathology of delusional disorders in patients exhibiting SLE is not well known. According to one hypothesis, ribosomal anti-protein P antibodies would bind to the neurones in certain cerebral localizations. Above all, knowledge of lupus in the course of delusional disorders has important therapeutic consequences, particularly on the use of high doses of corticosteroids.