A CASE OF A SHARED PSYCHOTIC DELUSION BETWEEN TWO SISTERS

Al Anood A. Al Thukair MD, Dina T. Al Afandi MD, Faten A. Azzoni MD, Hawra A . Al Johi MD, Hessa O. Al Otaibi MD and Lina M. Abu Gharara MD. College of Medicine, University of Dammam and King Fahd Hospital of the University, Alkhobar, Kingdom of Saudi Arabia. ...................................................................................................................... Manuscript Info Abstract ......................... ........................................................................ Manuscript History

Shared Psychotic Delusion (SPD) is a fascinating yet poorly understood psychological phenomenon. characterized by the transference of delusions from an individual who suffers already from a psychotic disorder, to mentally sane individual or individuals who are in close association and relative social isolation in a frame of complex and dependent relationship. In our case present a case of schizophrenic young female that transmitted her bizarre delusion of misidentification to her mentally sane sister after a period of total isolation and in a frame of a complex dependent relationship. Successful management plan composed of using antipsychotic that had led to significant improvement of the primary schizophrenic patient and simple physical separation cured the other Copy Right, IJAR, 2017,. All rights reserved.

Introduction:-
Shared Psychotic Delusion (SPD) is a fascinating yet poorly understood psychological phenomenon. This disorder was referred to as Folie à deux and Induced Psychotic disorder. However, it is nowadays known asShared Psychotic Disorder(SPD) as mentioned in DSM-5. SPD is characterized by the transference of delusions from an individual (the primary patient), who suffers already from a psychotic disorder, to mentally sane individual or individuals (the secondary patient) who are in close association and relative social isolation in a frame of complex and dependent relationship. [2] Methodology:-Interviews and full mental state assessment were held for both sisters before and after treatment. Family members were also involved throughout the process of diagnosis and treatment.

Case History:-
Miss (A) is a 26 years old Saudi female, college graduate. She lives with her sister Miss (B) who is a 29 years old, college graduate. They come from a religious family with an average socioeconomic status. Miss (A) has a domineering personality and a stubborn character with a special interest of astronomy and fortune telling. On the contrary, her sister Miss (B) is known to be passive and kind.

ISSN: 2320-5407
Int. J. Adv. Res. 5(2), 818-820 819 Miss (A) became psychotic with multiple bizarre delusions, including that her parents are imposters, herfather seems to be some sort of special DNA mixture of multiple historically famous figures and current celebrities, and thather biological mother is the former Indonesian housemaid.
According to these delusions, Miss (A) started to isolate herself and gradually became hostile towards all her family members. These delusions were transferred to her mentally sound sister Miss (B), after living in total isolation for 6 months' duration. One month prior to presentation, Miss (A) started to express aggressive behavior such as destroying properties, threatening others to be out of her life and eventually threatened her mother with a knife.
Miss(A) was forced to get admitted to a private hospital. There, she was diagnosed to have schizophrenia and was put on antipsychotics. Later on, Miss (B) was brought to our service where she was admitted for diagnosis. Miss (B) was found to have the same delusion but with a lesser extent and a less bizarre way, as mentioned by her family members. Simple separation of the sister was enough to shake and eventually resolve the delusion of the secondary patient (Miss B). While the primary patient was presented to our service for follow up and to keep on getting antipsychotic drugs (Zyprexa 10 mg PO BID, Risperdal 50mg IM every two weeks) with excellent responses later on. Finally, both sisters were gradually allowed to contact each other and thus returned to live in the same house.

Discussion:-
In 1651, Harvey was the first to describe an induced psychosis of phantom pregnancy in two sisters. The term Folieà deux dates to a classic report by Lasègue and Falret in 1877In 1942 [4]. Gralnick published a classification of four Folieà deux subtypes, as follows: • Subtype A is termed folieimposée. The delusions of a person with psychosis are transferred to a person who is mentally sound. Both persons are intimately associated, and the delusions of the recipient disappear after separation. • Subtype B is termed foliesimultanée. The simultaneous appearance of an identical psychosis occurs in two individuals who are both intimately associated and morbidly predisposed. • Subtype C is termed folie communiqué. The recipient develops psychosis after a long period of resistance and maintains the symptoms even after separation. • Subtype D is termed folieinduite. New delusions are adopted by an individual with psychosis who is under the influence of another individual with psychosis. [5] Our case fulfills the criteria of induced delusional disorder according to ICD10 and DSM IV with a specific Subtype A known as " folieimpose".
As stated through literature, the most common psychiatric disturbance is schizophrenia and the most common delusions are of persecution [6]. While our case involves delusion of misidentification.
Major cases in literature involve members of a nuclear family, most commonly is between mother and a child, husband and a wife or siblings. As suggested by other case reports, the primary patient is usually of an advanced age, have superior intelligenceand a forceful aggressive character. While the secondary patient is younger in age, passive, dependent and less intelligent than the primary one. However, In our case, the primary patient is neither older nor superior in inelegance, but has more dominating and stronger personality traits.
Furthermore, this relatively rare disorder has no systematic treatment regimen found to be effective. Inconsistencies in literature regarding treatment modalities exist between either one of two; Separation, as the sole treatment for the secondary, or psychotherapy and medical intervention in conjunction with separation, for cure of the secondary [6]. In our case, we separated them physically by admitting the primary patient to the psychiatric word and receiving antipsychotics. Individual psychotherapy and psychoeducation, were enough to cure the secondary patient.

Conclusion:-
It is crucial to recognize such rare cases in order to identify the exact approach of management. Such cases need intervention in a timely manner to understand the psychodynamic and plan for regular follow ups to help the patients to overcome such disorder.