Friday, March 29, 2024
HomePsychiatryShared Psychotic Disorder

Shared Psychotic Disorder

Background and Criteria

Shared psychotic disorder, or folie à deux, is a rare delusional disorder shared by 2 or, occasionally, more people with close emotional ties.
An extensive review of the literature reveals cases of folie à trois, folie à quatre, folie à famille (all family members), and even a case involving a dog.

In the most recent update to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), shared psychotic disorder was removed as a separate disease entity and was included in the section on other specified schizoprenic spectrum and other psychotic disorders. In the updated version the entity exists as “delusional symptoms in partner of individual with delusional disorder.”
 According to the DSM-5, in the context of a relationship, the delusional material from the dominant partner provides content for delusional belief by the individual who may not otherwise entirely meet criteria for delusional disorder.

ICD-10 diagnostic criteria for Induced Delusional Disorder (folie à deux) is as follows:

Two people share the same delusion or delusional system and support one another in this belief.

They have an unusually close relationship.

Temporal or contextual evidence exists that indicates the delusion was induced in the passive member by contact with the active partner.

Case study

Delalle et al presented a case of folie à deux in which paranoid delusions were shared by a mother and her 15-year-old son.
In this case, the mother was considered the dominant psychotic individual. The son was the passive recipient. The parent-child relationship, like spousal and sibling relationships, is very common in folie à deux. The son was treated with medication.

Soriano et al presented a case of folie à deux that occurred between 2 sisters.
As in the parent-child relationship, the occurrence of shared psychotic delusions among siblings is common due to the close ties. As the authors of this study discussed with regard to the sisters, the occurrence among siblings can be particularly attributed to shared past experience or expectations. The sisters shared delusions of persecution and prejudice toward the Chinese community of their hometown. The sisters were separated and given psychopharmacological treatment.

Peritogiannis et al investigated a case of folie à quatre, which not only presented the issues of close familial ties as a contributing factor, but also the complications of occurrence in rural areas.
The authors described a situation in which 4 adult cohabitating siblings were revealed to share delusions about their neighbors. None of the siblings were cooperative, and the authors suggested that mobile psychiatric units that worked with PCPs would be useful in diagnosing and treating the condition in rural areas.

Roth et al investigated an interesting case of folie à deux in a married couple, in which the delusions in the husband, the primary person, were caused by Huntington disease.
In an example of organic psychosis leading to shared psychotic disorder, the wife adopted her husband’s delusions through folie impossée, a category of folie à deux that occurs when the secondary person is otherwise mentally sound. Her condition quickly improved upon spatial separation from her husband.

Previous articleCognitive Deficits
Next articleLaryngeal Mask Airway
RELATED ARTICLES
- Advertisment -

Most Popular