Role of Social Isolation and Familial Dominance in the Development of Shared Psychotic Disorder: A Case Report (Preprint)

UNSTRUCTURED Background: Shared psychotic disorder (folie a deux) is a represents a small subset of psychiatric disorders that is defined by the spread of the delusional beliefs of an index subject to a nearby secondary person mostly in socially isolated dyadic units. Even though the disorder was previously outlined by Charles Lasègue and Jules Falret in the nineteenth century, it is still a diagnostic problem in the modern practice of clinical fields. Case Presentation: Here we report about a mother-daughter dyad with rural Indian origin. The index patient was a 49-year-old female with a documented schizophrenia history (two years old) with noncompliance to antipsychotics only recently. She had persecutory delusion and auditory hallucinations in the third person. Her 29-year-old daughter with no prior history of psychiatric problems presented a month later with the same persecutory delusions against her father and brother, however, she had no hallucinations. Dominant and submissive relationship and prolonged social isolation were observed in the family. Intervention and Outcome: There was a very little improvement in the daughter with initial therapeutic separation. At one week, the mother responded to olanzapine 10mg. The daughter needed to be prescribed a lower dose of olanzapine (2.5mg) and showed considerable changes in ten days. Conclusion: The case highlights that there is a need to acknowledge shared psychosis in the socially isolated family systems and that pharmacological intervention is a supplementary treatment to separation that can be crucial in bringing the best possible recovery.