The induced delusional disorder or folie à deux, is a rare condition characterized by psychotic symptoms at least in two individuals in close association.

We report a case of shared psychotic disorder between mother and daughter. We briefly review both classical and current literature.

We summarized the results from articles identified via MEDLINE/PubMed using “induced delusional/shared psychotic disorder” as keywords. We report a case of a woman who develops psychotic symptoms characterized by delusions of persecution. Her daughter started, during the first high school grade with referring sexual threats and having delusions of persecution lived by her mother like a fact. They have very symbiotic relationship. Seven years later, the mother has required hospitalization for chronic delusions.

The term folie à deux was first coined by Lasègue and Falret, they assume the transmission of delusions was possible when an individual dominated the other and existed relative isolation. Recent studies found no significant differences in age and sex, although described higher comorbidity with other psychiatric diseases. Relative to treatment, separation by itself is insufficient; an effective neuroleptic treatment is required.

Our case meets criteria for shared psychotic disorder. The daughter, with a ruling attitude who dominates the relationship, was the inducer. The mother showed no resistance in accepting delusions and remains them active after separation. This leads us to consider the possible predisposition to psychotic illness by both patients.

The authors have not supplied their declaration of competing interest.