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Year : 2014  |  Volume : 1  |  Issue : 1  |  Page : 36-40

Shared delusional disorder: A case report of Folie a trois

Department of Psychiatry, Silchar Medical College, Silchar, Assam, India

Date of Web Publication29-Jan-2015

Correspondence Address:
Prosenjit Ghosh
Parijat Apartment, College Road, Ambicapatty, Silchar - 788 004, Assam
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Source of Support: None, Conflict of Interest: None

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Induced delusion of having syphilis in the two members of a family from the elder sister who had no past history of psychiatric illness. Early diagnosis, antipsychotics and physical separation showed marked improvement within 2 months. The psychopathology and socio demographic variables showed marked variation from earlier concepts regarding the shared delusional disorder (SDD).

Keywords: Delusion, folie a trois, folie a famille, induced delusional disorder

How to cite this article:
Ghosh P. Shared delusional disorder: A case report of Folie a trois. Eur J Psychol Educ Studies 2014;1:36-40

How to cite this URL:
Ghosh P. Shared delusional disorder: A case report of Folie a trois. Eur J Psychol Educ Studies [serial online] 2014 [cited 2021 Apr 23];1:36-40. Available from: https://www.ejpes.org/text.asp?2014/1/1/36/150275

  Introduction Top

A delusion may be defined very loosely as a mistaken idea which is held unshakably by the patient and which cannot be corrected. As will be seen, this is not a satisfactory definition, although it may be a useful starting-point for clinical recognition of a delusional process. Karl Jaspers contributed significantly on the phenomenology and psychopathology of delusions, [1] and his work continues to influence the views of many psychiatrists. From the 1970s onwards, interest in paranoia began to reappear [2],[3] and [4] in 1987, DSM-IIIR [5] renamed it delusional (paranoid) disorder, now simplified to delusional disorder in DSM-IV [6] and ICD-10. [7] All cases of delusional disorder occur in clear consciousness and have a stable and persistent delusional system which is relatively encapsulated. Since much of the personality remains remarkably intact, a considerable degree of social functioning is retained in many cases. The patient experiences a heightened sense of self-reference within the delusional context and ordinary events take on extraordinary significance. Delusional disorder has many subtypes based on the theme of the Delusion. DSM-IV recognizes five main subtypes of the illness based on the predominant delusional themes: the erotomanic, grandiose, jealous, persecutory and somatic, and mixed and unspecified types. ICD-10 also recognizes these subtypes, and adds litigious and self-referential The somatic delusional disorder is also known as Monosymptomatic Hypochondriacal Psychosis. Hypochondriasis refers to a persistent conviction of illness in absence of any evidence of illness. Hypochondriacal Delusional disorder may have various themes involving-Delusion involving skin, Delusion involving bodily shape, Delusion of bodily odor and Delusion of having sexual disorders. [8]

Delusion of sexually transmitted disease [9]

Hypochondriasis is, of course, rampant around the topic of sexually transmitted disease. A subgroup of delusional disorder patients develop the conviction that they have venereal disease, often when there is no evidence of risk-taking behavior having occurred. In the past syphilis was probably the greatest fear, but nowadays it is usually AIDS. Repeated tests showing negative serology have no reassuring effect.

Shared delusional disorder

A delusional disorder shared by two or more people with close emotional links. This phenomenon is listed as a psychiatric disorder in DSM-IV (Shared Psychotic Disorder, 297.3) and in ICD-10 (Induced Delusional Disorder, F24).

Folie à deux is a venerable term used to describe a situation in which mental symptoms, usually but not invariably delusions, are communicated from a psychiatrically ill individual (the 'primary patient') to another individual (the 'secondary patient') who accepts them as truth. However, à deux may sometimes be a misnomer since several people can be involved, and then we read of folie à trois, folie à plusieurs, folie à famille etc.

This report looks at an unusual case of three members of a family developing a somatic delusional disorder with the theme of having sexually transmitted disorder.

  Case Report Top

Mrs. A, young female of rural background, aged around 28 years, separated from husband for last 1 year after 7 years of marriage, childless and presently living in her paternal house with parents, brother and sister-in-law, was referred for psychiatric consultation by a general surgeon. Her complains were persistent lower abdominal pain, itching in the genital area and a sensation of germs crawling under the skin of her lower abdominal and genital area for last 6 months. Because of her persistent complain she had undergone two abdominal operations in last 6 monthsexploratory laparotomy and cholecystectectomy. But her symptoms persisted, although she can perform her daily activities and had intact interpersonal relationships.

She had no past history of psychiatric illness; there was no family history of psychiatric illness either. Her birth, developmental milestones and early childhood history were normal. The family was very close knit and they used to take food together even from the same utensil. She studied up to class eight standard. She had no history of substance abuse, married but separated, had no premarital or extramarital sexual experience. She had no child and gives a history of irregular menstrual cycle. Premorbidly she was cheerful; religious was dominating and had good moral values.

Her mental status examination revealed an encapsulated delusion of being infested with the virus of syphilis. She had a strong conviction about her delusional belief and the negative results of multiple veneral disease research laboratory (VDRL) tests could not shake her belief. She said that at night the germs crawl under her skin and comes out of her vagina. She also believed that the virus is responsible for her infertility, weakness and white discharge per vagina. She also had an anxious mood. Her cognitive functions were intact. She was diagnosed as a case of delusional disorder, somatic type. She was put on Tab Aripiprazole 15 mg at night and other supplementary medicines. She received various psychological inputs. She was also given psycho education about the nature of illness.

Mr. B, brother of A, aged about 26 years had also come for consultation on the same day. His complains were weakness, lethargy, loss of appetite, abnormal sensation under the skin of lower abdomen and lower limbs and tingling sensation in the feet for last 5 months. He had no significant past medical or psychiatric illness. He was a driver, married, had one child, and had no history of substance abuse, no history of sexual exposure to sex workers.

On mental status examination the findings were-anxious mood, somatic preoccupation, a somatic delusion of being infected with the virus of syphilis. He said that in their household they take food and water from the same utensils. He was very close to his sister and they often drink water from the same glass, and he is convinced that the virus entered his body through water from the mouth of his sister. He said that the abnormal sensation in his skin is due to the movement of the virus. He had no perceptual abnormalities and had normal cognitive functions.

He was diagnosed as a case of somatic delusional disorder. He was put on Tab Aripiprazole 10 mg at night and psycho education was given.

Mrs. C, wife of Mr. B, aged about 21 years, house wife, had come with the complains of-weakness, abnormal sensation in the lower limbs and lower abdomen, nervousness, loss of appetite for last 4 months. She had no past or family history of psychiatric illness. She was married for last 3 years, had one child, and had no history of pre or extra marital sexual relationship. Her physical examinations were normal. Her mental status examination revealed anxious mood, somatic preoccupation, somatic delusion of being infected with the virus of syphilis. She showed multiple black spots on the sole of her feet as evidence of the infection. She also said that at night her sufferings were more. She was convinced that she acquired the infection from her husband through food. Her blood investigations were normal. She was diagnosed as a case of somatic delusional disorder. She was put on Tab Aripiprazole 5 mg daily.

Mr. B and Mrs. C were advised to stay away from Mrs. A for 30 days. On follow-up after 30 days there was remarkable improvement in B and C. Mrs. A was also showing improvement. After 8 weeks all the three cases were much improved. After 6 months, A was on Tab Aripiprazole 5 mg daily, and the other two patients were not on any medications, all were improving.

  Discussion Top

Harvey described the first case of phantom pregnancy associated with induced psychosis in two sisters in 1651, the term folie à deux dates to a classic report by Lasègue and Falret in 1877. [10] In 1942, Gralnick [11] published a classification of four folie à deux subtypes. These subtypes are as follows:

  • Subtype A is termed folie imposée. 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 folie imposée. 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 folie induite. New delusions are adopted by an individual with psychosis who is under the influence of another individual with psychosis.

Our cases met the current operational criteria for shared delusional disorder (SDD) as described in DSM IV and ICD 10. Mr. B and Mrs. C were closely related with Mrs. A and were staying together for a considerable period time. Both B and C had no prior history of psychiatric illness and the contents of their delusional belief were identical to that of Mrs. A. Temporal evidence shows that delusion was transferred to B and C (secondary) by close contact with A (primary). The conviction level was highest in the primary (A) regarding the delusion of being infected with Syphilis; she also needed higher doses of antipsychotics for a longer period. Both the secondary cases (B and C) showed remarkable improvement after separation from the primary and they also needed lower doses of psychotropics for a shorter period. In fact C had weaker conviction level regarding her delusion. Folie `a trois is said to be present when three members of the same family are involved. So the three members of the same family developing similar delusional belief in close proximity fulfill the criteria to be called SDD, Folie a trois, simultanee subtype.

Although the phenomenon of SDD is not very common, recently they are being increasingly reported. A case of folie a deux was reported earlier from India, which occurred in non family. [12] Manickam [13] described a case of induced delusional disorder or folie a deux in a 19-year-old girl from India whose 16-years-old younger sister had paranoid schizophrenia. Ivan Netto [14] from Pune reported a case of folie a deux (2010), where 64-year-old male Mr. X and his 53-year-old wife Mrs. Y were brought by their relatives. They were married for the last 25 years and both shared persecutory ideas against their cook and neighbors. The couple felt that they were plotting against them to kill them and take away their ancestral property. Bora [15] reported an interesting case of four children of the same family of Merapani area of Golaghat district of Assam near the Nagaland border, who were living in the most unusual way in their rooms day and night without any interaction with any person except with the mother since about 8-10 years. Nilesh shah [16] described a case of SDD, where a 60-years-old father transferred his persecutory delusion to his wife and one daughter.

Contrary to earlier belief it has been shown that SDD can affect any age-group. Lazarus [17] reviewing fifteen twin case reports found one of the partners to be 20 years of age. In case of Merapani children the age of onset was about 8-10 years. Delalle [18] presented a case of folie à deux in which paranoid delusions were shared by a mother and her 15-year-old son. In our case all the three subjects are young adults.

Out of the three cases two were female and one was male. The Primary was elder to both the secondaries. In most of the cases reported from India the Inducer was elderly to the Acceptor. However, Manickam [13] reported a case where the Inducer/Primary was younger to the Acceptor/Secondary.

Our subjects had close emotional relationship. The primary was the dominant person among the three. The relationship of the affected was sister-brother and sister-in-laws. This may explain that both genetic/early childhood experience and environmental factors are important in the causation of SDD. The relationship between the inducer and the induced has been traditionally viewed in terms of a dominant-submissive axis. Dippel [19] also described a case of Folie a six where the delusion of the central figure was transmitted to her husband, two sons, sister-in-law and nephew.

However our subjects were not socially isolated, and had almost normal social functioning. Dippel also did not find any adverse social or environmental circumstances.

Shimizu et al.,(2007) [20] examined demographic data of SDD case reports published from the nineteenth to the twenty-first century and found that some of the earlier hypotheses, such as females being more susceptible, older and more intelligent individuals are more likely to be inducers, and sister-sister pairs being the most common relationship, were not supported.

Our cases had a delusion of being infected with the virus of Syphilis. To the best of our knowledge there is no published report of SDD involving the theme of sexually transmitted disease. Majority of the reported cases of SDD involve Persecutory delusions (Soriano et al., 2009, Bora et al., 2012, van Amerongen AS 2013). [15],[21],[22] The dominating primary case is most commonly represented by persons with schizophrenia, delusions, or mood disorders. In Western countries, both the original delusions in the dominant person and the induced delusions in the submissive person are usually chronic and either persecutory or grandiose in nature. An accurate assessment of the epidemiology of delusional disorder is hampered by the relative rareness of the disorder, as well as by its changing definitions in recent history. Moreover, delusional disorder may be underreported because delusional patients rarely seek psychiatric help unless forced to do so by their families or by the courts. The prevalence of delusional disorder in the United States is estimated to be 0.025-0.03%. Thus, delusional disorder is much rarer than schizophrenia. According to the text revision of the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR), delusional disorders account for only 1-4% of all admissions to inpatient mental health facilities. The mean age of onset is about 40 years, but the range for age of onset runs from 18 years of age to the 90s. A slight preponderance of female patients exists. Men are more likely to develop paranoid delusions than women, who are more likely to develop delusions of erotomania. [23] Many patients are married and employed, but some association is seen with recent immigration and low socioeconomic status. In Japan, acute psychotic reactions have been noted to be delusions of a religious nature (Sharon et al. 2011). [24]

None of our cases had any past or family history of psychiatric illness. Most of the earlier reports had found past history of Schizophrenia, Psychosis or Personality disorder in the inducer/primary case (Netto et al., 2010, Manickam et al., 1997). [13],[14] Our cases had significant improvement within 6 weeks of treatment; the delusional belief was absent in the two induced persons and the level of impairment was also minimum, reason may be lack of past history of psychiatric illness and separation of the primary case from the secondary cases. We have used antipsychotics and psychotherapy in the form of individual psychotherapy and psychoeducation along with physical separation. The aim of psychotherapy was to help them recognize the delusion and to correct the underlying distorted thinking. [25] Bankier, following the traditional literature, recommends physical separation, antipsychotic medication, and psychotherapy to treat folie à deux. Medications administered along with psychotherapy accelerate the process of recovery.

  Conclusion Top

Our case report emphasizes the following points needed to be remembered by a Psychiatrist.

Shared delusional disorder is not uncommon. If not properly diagnosed, the patients may undergo unnecessary investigations and procedures. The role of family in sustaining delusional belief should be addressed. The phenomenon of shared delusional disorder can occur in absence of - social isolation, past history of psychiatric illness and subnormal intelligence. Environmental factors-married, being employed, recent immigration, low socioeconomic status, celibacy among men, and widowhood among women are important in causation and management. [26]

Both genetic and environmental factors are important in the causation of such disorders. The shared delusional disorder can affect any age group. The management should include drug therapy, psychotherapy and physical separation if needed.

  References Top

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Winokur G. Delusional disorder (paranoia). Compr Psychiatry 1977;18:511-21.  Back to cited text no. 2
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American Psychiatric Association. Diagnostic and statistical manual of mental disorders (revised 3 rd ed). Washington: American Psychiatric Association; 1978.  Back to cited text no. 5
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New Oxford Text Book of Psychiatry. Vol 1. Oxford: Oxford University Press; 2003.  Back to cited text no. 8
Bhanji S, Mahony JD. The value of a psychiatric service within the venereal disease clinic. Br J Venereal Dis 1978;54:266-8.  Back to cited text no. 9
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Netto I. Folie a Deux - A case study article. Orrisa J Psychiatry 2010;XVII: 54-6.  Back to cited text no. 14
Bora BP, Baruah C. Merapani children: A rare folie en famille (shard psychotic disorder). In: Das S, editor. Souvenir-cum-Scientific Update for the 22 nd Annual Conference of Indian Psychiatric Society, Assam State Branch. Guwahati: ABSCON; 2012. p. 25-30. Available from: http://sites.google.com/site/ mindtheyoungminds/souvenir-cum- scientific-update/merapani-children-a-rare- folie-en-famille-shared-psychotic-disorder [Last accessed on 2013 Aug 13].  Back to cited text no. 15
Netto I, Shah N.Folie `a famillie in a family multiply affected with schizophrenia. Indian J Psychiatry 2011;53:372-3.  Back to cited text no. 16
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Iazarus A. Folie a deux in identical Twins: Interaction of nature and nurture. Br J Psychiatry 1986;151:258-60.  Back to cited text no. 17
Dodig-Curkovic K, Curkovic M, Degmecic D, Delalle M, Mihanovic M, Filakovic P. Shared psychotic disorder ("folie a deux") between mother and 15 years old son. Coll Antropol 2008;32:1255-8.  Back to cited text no. 18
Dippel B, Kemper J, Berger M. Folie a six: A case report on induced psychotic disorder. Acta Psychiatr Scand 1991;83:137-41.  Back to cited text no. 19
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Martinezde Velasco Soriano R, Benitez Cerezo E, Pando Velasco MF, Erausquin Sierra C, Gobernado Ferrando I, Suarez Martin F, et al. Shared-induced paranoid disorder (folie a deux) between two sisters. A case report. Eur Psychiatry 2009;24:S1118.  Back to cited text no. 21
van Amerongen AS, Verheijden EE, van Gent NM, Moaddine N, de Winter RF, Blom JD. Folie à famille: A Surinamese-Hindustani family with a shared paranoid delusion and severe undernourishment. Tijdschr Psychiatr 2013;55:123-7.  Back to cited text no. 22
Sadock BJ. Delusional and shared psychotic disorder. In: Sadock BJ, Sadock VA, editor. 10 th ed. Vol. 1. Kaplan and Sadock′s Synopsis of Psychiatry. United States : Lippincott Williams and Wilkins. 2007. p. 505.  Back to cited text no. 23
Sharon I, Bienenfeld D. Shared psychotic disorder. Medscape [Internet] 2011. Available from: http://emedicine.medscape.com/article/293107-overview [Last cited on 2012 Sep 9].  Back to cited text no. 24
Shared Psychotic Disorder. Cleveland Clinic [Internet]. Available from: my.clevelandclinic.org/disorders/psychotic_disorder/hic_shared_psychot [Last accessed on 2013 Aug 13].  Back to cited text no. 25
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