Fregoli syndrome in schizophrenia: about a case report

A Fregoli syndrome, just like Capgras Syndrome, Double Subjective Syndrome, and Inter metamorphosis Syndrome, belongs to the group of delusion misidentification syndromes. It is a rare neuropsychiatric pathology that could affect the brain with repercussions on behavior. It is the belief that a familiar person is disguised as a strange person by taking a different physical appearance but remains the same person psychologically. This entity has heterogonous etiologies, occurring mainly in the setting of organic diseases, affective disorders, or schizophrenia. In this article, we proposed to expose a case of a schizophrenic patient who developed Fregoli syndrome.

A Fregoli syndrome, just like Capgras Syndrome, Double Subjective Syndrome, and Inter metamorphosis Syndrome, described for the first time in 1927 by Courbon and Fail belongs to the group of delusional misidentification syndromes (DMS) [1]. The delusions of identity or identification are defined by an alteration in the identification of people, objects, places, events, and parts of the body. They are accompanied by the conviction of duplication, multiplication, or even a replacement of what is the object of identity alteration [2,3]. These rare neuropsychiatric pathologies posed challenges to mental health professionals due to a lack of comprehensive understanding of, especially, Fregoli and Capgras syndromes [2,3].

Neurophysiological and neuroimaging studies have pointed to the presence of brain damage and organic cerebral dysfunction, in particular in the right hemisphere. However, most cases occur in the setting of schizophrenia [2,4]. In this article, we reported a case of a schizophrenic patient who developed Fregoli syndrome.

We report, here, the case of Ms. F. A 50-year-old widowed woman, living with her mother and her 18-year-old daughter who doesn’t work. She had a family history of intellectual disability in her sister and personal history of hypertension under treatment. Besides, she consulted, a few years ago, a free practice psychiatrist for irritability. Ms. F. was put on an unspecified treatment taken for a few days and then stopped by the patient. The onset of the disorders goes back several years when the patient was 34 years old. At that time, she developed the belief that one of her colleagues Mr. S had a special affection for her. She was totally convinced that he wanted to have a sexual relationship without her consent.

According to the patient, she felt embarrassed and bothered because she strongly claimed that all other colleagues started gossiping about this subject. Besides, she said that this man’s goal was to force her to change her Muslim religion to become a Jew. Consequently, the patient quit her job. However, this person, who is disguising himself as a different man, continued to search for her in front of her house. She even moved to another city to live with her sister, but she kept seeing different versions of this man whom she saw everywhere (in front of the house, at the supermarket, in the street...).

Then, she developed the belief that her daughter’s fiancé is actually her colleague Mr. S in disguise and he wanted to marry or have a sexual relationship with her. This created a lot of family conflicts. In addition to these misidentifications, she also had auditory and visual perceptions. Therefore, she was referred to our inpatient psychiatry department, in October 2019, for further support.

During the interview, Ms. F. was very anxious and she hid her face with a scarf. According to her, in this way, the different versions of Mr. S would not know her. We noted a mystical, referential, sexual polythematic delirium with an intuitive, interpretive and hallucinatory mechanism essentially auditory, with behavioral and emotional reactivity. She reported that her daughter’s fiancé, which is in reality Mr. S., wanted to have sex with her and to force her to change her religion. This same person with different physiques but the same psychological features followed her everywhere.

The patient underwent a standard workup, thyroid workup and brain computed tomography; the results did not show any abnormalities. Also, magnetic resonance imaging was indicated, but not performed because of the low socioeconomic level’s patient.

This case highlights significant psychopathologies that qualified her for the diagnosis of schizophrenia associated with Fregoli syndrome.

Ms. F. was initially started on Risperidone 2 mg per day. The treatment was gradually increased to 4 mg and then 6 mg because of the persistence of the delusion. After 8 weeks of treatment (dose of 6 mg), the patient started showing improvement with a partial decrease in delusion activity and less reactivity. Over the last two years, she was treated, and the patient was followed regularly. Clinically, there was remission in hallucinatory activity. In addition, the delusional belief was still present; but, it no longer affected her behavior.

Actually, Fregoli syndrome is the belief that a familiar person is disguised as a strange person by taking a different physical appearance but remains the same person psychologically [1].

The present state of knowledge regarding this phenomenon is based mostly on reported cases and subsequently still insufficient. It seems that DMSs show a great degree of overlap and do not represent distinctive syndromes and they may be the manifestation of several mental or organic illnesses such as hypothyroidism, right hemispheric stroke, multiple sclerosis, and dementia, namely Alzheimer’s disease [3]. In fact, several studies suggest that DMS is a result of brain damage, such as infractions [5], traumatic injuries [6], or other types of brain lesions [3,5–7]. Also, DMSs can be a manifestation of an underlying psychiatric disorder, most commonly schizophrenia [7,8]. As well as other reported cases [3,4,9], this observation reveals a patient without obvious organic etiology and presenting Fregoli syndrome. In addition, there were significant psychopathologies (bizarre qualities of delusions and hallucinations) that qualified her for the diagnosis of schizophrenia.

Many aspects of these complex phenomena remain unclear. However, neuropsychological research provided empirical support for the presence of right hemisphere abnormalities and impairments of face processing regions in the brain [3,6]. It was shown, also, that DMS is associated with executive and memory deficits [6]. So, hyperactivity in the cerebral cortex predominantly in the right hemisphere seems to account for hyper familiarity seen in this syndrome [10].

For such patients, the treatments available today are not fully effective [3]. In some case reports, Fregoli syndrome, in the setting of schizophrenia, may respond to antipsychotic treatment and in some cases to Electroconvulsive therapy [3,11].

Fregoli syndrome can have serious repercussions on personal, professional, and social life. As in the present case, type identification creates multiple familial conflicts and affects social behavior causing suffering among the patient and her entourage. Therefore, many efforts for a better understanding of the DMS phenomena and effective treatment measures are really needed.

1. Ellis HD, Young AW. Accounting for delusional misidentifications. Br J Psychiatry. 1990 Aug;157:239-48. doi: 10.1192/bjp.157.2.239. PMID: 2224375.
2. Walther S, Federspiel A, Horn H, Wirth M, Bianchi P, Strik W, Müller TJ. Performance during face processing differentiates schizophrenia patients with delusional misidentifications. Psychopathology. 2010;43(2):127-36. doi: 10.1159/000277002. Epub 2010 Jan 23. PMID: 20110765.
3. Atta K, Forlenza N, Gujski M, Hashmi S, Isaac G. Delusional Misidentification Syndromes: Separate Disorders or Unusual Presentations of Existing DSM-IV Categories? Psychiatry (Edgmont). 2006 Sep;3(9):56-61. PMID: 20975828; PMCID: PMC2963468.
4. Kumar PNS, Gopalakrishnan A, Williams M. A case of Fregoli syndrome in schizophrenia. Asian J Psychiatr. 2018 Aug;36:119-120. doi: 10.1016/j.ajp.2018.07.003. Epub 2018 Jul 23. PMID: 30071488.
5. de Pauw KW, Szulecka TK, Poltock TL. Frégoli syndrome after cerebral infarction. J Nerv Ment Dis. 1987 Jul;175(7):433-8. doi: 10.1097/00005053-198707000-00008. PMID: 3598572.
6. Feinberg TE, Eaton LA, Roane DM, Giacino JT. Multiple fregoli delusions after traumatic brain injury. Cortex. 1999 Jun;35(3):373-87. doi: 10.1016/s0010-9452(08)70806-2. PMID: 10440075.
7. Cipriani G, Vedovello M, Ulivi M, Lucetti C, Di Fiorino A, Nuti A. Delusional misidentification syndromes and dementia: a border zone between neurology and psychiatry. Am J Alzheimers Dis Other Demen. 2013 Nov;28(7):671-8. doi: 10.1177/1533317513506103. Epub 2013 Oct 27. PMID: 24164927.
8. Gupta M, Gupta N, Zubiar F, Ramar D. Delusional Misidentification Syndromes: Untangling Clinical Quandary With the Newer Evidence-Based Approaches. Cureus. 2021 Dec 4;13(12):e20165. doi: 10.7759/cureus.20165. PMID: 35003994; PMCID: PMC8723768.
9. Kochuparackal T, Simon AE. A "contemporary" case of frégoli syndrome. Prim Care Companion CNS Disord. 2012;14(1):PCC.11l01227. doi: 10.4088/PCC.11l01227. Epub 2012 Jan 26. PMID: 22690358; PMCID: PMC3357570..
10. Devinsky O. Delusional misidentifications and duplications: right brain lesions, left brain delusions. Neurology. 2009 Jan 6;72(1):80-7. doi: 10.1212/01.wnl.0000338625.47892.74. PMID: 19122035.
11. Christodoulou GN. Treatment of the "syndrome of doubles". Acta Psychiatr Belg. 1977 Mar-Apr;77(2):254-9. PMID: 20738.