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Uxoricide by a schizophrenic patient with delusional misidentification syndromes: A case report

Abstract Delusional misidentification syndromes in psychiatric disorders might result in dangerous behavior leading sometimes to homicide. An early diagnosis and thorough follow up is important to avoid such consequences.


| INTRODUCTION
The delusional misidentification syndromes (DMS) are psychiatric disorders involving deviation from normal process of recognizing people. The three most prominent DMS are Capgras delusion, 1 Frégoli delusion, 2 and intermetamorphosis. 3 Capgras delusion was first described by Capgras and Reboul-Lachaux in 1923. The patient holds the delusion that a close family member has been replaced by an identical impostor. As for the Frégoli delusion, it was first described by Courbon and Fail in 1927. Here, the patient believes that a familiar person is disguised as a strange person. The familiar person has taken on another appearance physically but remains the same person psychologically. Generally, the persecutor returns by incarnating people from entourage. DMSs are frequently associated with aggressive behavior and even criminal acts. An early assessment of these syndromes is important in order to predict potentially dangerous behavior in these individuals. Here, we report a schizophrenic patient who committed uxoricide in a Capgras delusion context. The patient had a Frégoli delusion as well resulting in aggressive behavior toward the other patients.

| CASE REPORT
Mr. A is a 50-year-old farmer diagnosed with schizophrenia who was addressed to our department in 2018 after committing uxoricide. The patient has family history of psychosis in a first-degree relative.
He lived in the countryside with his family where the socio-cultural backwardness prevails. He completed elementary school and dropped out right after to help his father with the farm work. After the latter died when he was still 29 years old, he took after him. The patient was described to have poor social interactions since young age.
He was hospitalized in 1999 for 14 days in ICU for cranial trauma after being hit by a car. The onset of his psychiatric symptoms took place a year after, and he was followed up since then for schizophrenia in another psychiatric department. During the follow-up, the patient did not regularly present to the hospital and was hospitalized 5 times for intra-and extra-familial aggressiveness. He got married in 2014 at the age of 42 and had a daughter a year after. The marital relationship was characterized by continuous conflicts.
Since 2016, he reduced social interactions gradually and stopped working. He had auditory and visual hallucinations resulting in significant mental distress. The patient was hearing many voices talking among themselves and sometimes mocking and laughing at him. Furthermore, he had delusional misidentification syndrome (Capgras delusion). He claims that his wife is an impostor who took on the appearance of his wife and was aiming to harm him through witchcraft. During the same year, in a quarrel with the wife, he started beating her head violently with a stick. The frightened wife run away to the neighbors but he chased after her and continued beating her head until she passed away. When his mother visited him in forensic psychiatry department, he said she only looked like his mother but actually wasn't. The patient had persecutory delusions toward his brother Mr.R. He claims that he was sexually abusing him as well as his wife and daughter. During his hospitalization, he got into conflicts with two patients since he was convinced that they were actually his brothers disguising under their appearances and taking their names (Fregoli delusion). The patient had also hypochondriacal delusions. He claimed that he no longer had a heart and that his heart was dead with witchcraft.
He was started on treatment with fluphenazine 150 mg/day and stopped treatment on his own, and when restarted during his last hospitalization in 2018, it was poorly tolerated. So, it was switched to olanzapine. His convictions toward his delusions have not changed, and his insight was poor. An association with sodium valproate and then with risperidone was attempted but with no clear improvement.

| DISCUSSION
The delusional misidentification syndromes (DMSs) are psychopathologic phenomena in which a patient misidentifies persons, places, objects, or events. These delusions can be the greater part of the presentation or secondary to several psychiatric and neurological disorders. The patients with such delusions are more frequently involved in acts of violence. It is imperative to assess the risk of aggression, mainly, against the "impostor," in order to prevent it.
The prevalence of DMSs was estimated at 3%-4% in psychiatric population with most cases happening in schizophrenia. 4,5 However, DMSs should be more common than previously supposed to due to the absence of reliable and standardized diagnostic criteria. 6,7 Prior reports indicate that schizophrenia is the most common mental disorder found in patients with DMSs. Organic mental disorders such as dementia were reported in other cases. 8,9 Fregoli delusion is the misidentification of a real person as a different known person appearing in the physical guise of the real person. Multiple real persons can be misidentified as a single known person. 10 It was the case of our patient. This syndrome had been associated with organic cerebral damage particularly a temporolimbicfrontal disconnection; however, most cases occurred in the setting of schizophrenia. 11 Christodoulou et al. suggested that organic brain damage contributed to the pathogenesis of Fregoli syndrome. They reviewed seven cases of paranoid schizophrenia patients who developed Fregoli syndrome only after brain damage. 12 Capgras delusion is the belief that a visually similar impostor had replaced someone emotionally close, usually the spouse. A systematic review of 255 Capgras cases reported that the most frequent diagnoses were schizophrenia, organic psychosis, and dementia. 13 Two antagonistic forms of DMS are the hypoidentification (Capgras) and the hyperidentification (Fregoli) syndromes. Whereas in Capgras the problem is the underactivation of normal autonomic arousal, the problem in Fregoli is excess inappropriate arousal to viewing unfamiliar faces. Therefore, both syndromes could not occur at the same time according to Ramachandran and Blakeslees. 14 However, the co-occurrence of Fregoli and Capgras was reported in the literature. 15,16 The two cases happened with women with paranoid schizophrenia. Both syndromes were identified in our patient as well.
Recently, the percepts of cognitive neuropsychiatry have prevailed. Cognitive neuropsychiatry has suggested face recognition models explaining the impairment occurring in such patients. Ellis and Young were the first to propose an explanation of some DMSs using a cognitive model of normal face processing (Bruce and Young's 1986 cognitive model). 17 With some modifications, Langdon et al. used the same model to develop an illustration explaining prosopagnosia and Capgras delusion. 18 The DMSs are characterized by hostility toward misidentified subjects. 19 Dangerous DMS individuals might harbor silent delusions and provide no verbal warning until physical aggression. This finding may have an explanation of forensic significance. 9 In a systematic literature search reviewing 15 cases of violence in a DMS context, most of the patients were men with schizophrenia and Capgras syndrome. 20 Capgras syndrome was identified as a specific risk factor for violence against the misidentified person. 21 The delusional misidentification contributed to growing ideas of persecution and aggressive behavior, which led to homicide. 9,22,23 Our patient committed uxoricide in the context of Capgras delusion.
The Fregoli delusion is a less common DMS. The violent behavior was also reported. [24][25][26] In conclusion, the case reported here highlights the association between a major psychiatric disorder in a phase of acute decompensation and the delusional misidentification syndrome resulting in homicide and aggressive behavior. It is essential to identify such syndromes and evaluate the dangerousness in these patients.

AUTHOR CONTRIBUTIONS
Ghada Hamdi conceived the idea. Sameh Bougatf collected the data, wrote the manuscript, and performed a critical revision.