Capgras' Delusion: A Systematic Review of 255 Published Cases

Capgras syndrome in children and adolescents: A systematic review

OBJECTIVES

To improve understanding of Capgras syndrome (CS) in the pediatric population, this study investigates its clinical features and discerns similarities and differences compared to CS in adults.

METHODS

We conducted a descriptive systematic review of case reports following PRISMA guidelines, including cases of pediatric patients with CS. Patient demographics, medical and psychiatric history, imposter identity, underlying diagnosis, clinical manifestation, treatments, and outcomes were extracted and analyzed.

RESULTS

We included 37 articles comprising 38 cases. The median age of patients was 15, with 23 (60.5%) being male. The most prevalent underlying diagnoses were schizophrenia spectrum and other psychotic disorders (47.3%). Imposter identity involved parents in 32 cases (84.2%). Associated symptoms included persecutory delusions (63.1%), auditory hallucinations (42.1%), aggression (31.5%), and depression (21.0%).

CONCLUSION

There is a significant gap in our understanding of CS, particularly in pediatric patients. This is the first systematic review of CS in pediatric patients, encompassing all cases found in English literature since 1923.

Importance of Capgras syndrome in shared psychotic disorder: a case report

Shared psychotic disorder characterized by Capgras syndrome is an extremely rare condition. To our knowledge, there are only a few published papers on this condition. This paper presents a case of shared Capgras syndrome in two sisters. The inducer was a younger sister with schizophrenia, who passed on her Capgras delusion to her older sister after the death of their father. After committing a violent offense caused by Capgras delusion, a court ordered the sisters' involuntary admission to a psychiatric hospital. After being separated and receiving antipsychotic treatment, the sisters showed substantial improvement. However, shortly after hospital discharge, they stopped taking their medication and disappeared. After 15 years, their mother died and shortly afterwards, the sisters were re-admitted for forensic psychiatric evaluation after another violent crime caused by Capgras delusion. Timely recognition, adequate treatment and maintaining a therapeutic alliance could contribute to a better clinical course and outcome of this disorder, and reduce the risk of violent behavior.

Coexistence of different delusional misidentification syndromes in clinical practice: A case series

OBJECTIVE

The objective of this study is to analyse the coexistence of several delusional misidentification syndromes in a clinical sample.

METHODS

Over one year, a sample of six patients presenting two or more types of delusional misidentification syndromes was selected. All these patients were admitted to the psychiatric inpatient unit of a Spanish hospital.

RESULTS

Despite the different diagnoses, the patients included presented different types of delusional misidentification syndromes, both hyperidentification and hypoidentification. Antipsychotic treatment was not very effective against these delusional misidentification syndromes.

CONCLUSIONS

The coexistence of several delusional misidentification syndromes indicates that the aetiopathogenesis of the different types is similar. It is a field with important clinical implications, due to the poor response to treatment, as well as the possible medico-legal implications.

Schizophrenia Misdiagnosis after Capgras and Cotard Delusions in a Patient with Infantile Cystinosis, Cavum Septi Pellucidi, Cavum Vergae and Cavum Veli Interpositi

How many patients with psychosis secondary to genetic conditions or congenital brain malformation have been diagnosed with schizophrenia, since its initial conception more than one hundred years ago? A case report of a young man, with antecedents of Capgras and Cotard syndromes, sent to a schizophrenia treatment-resistant outpatient clinic is presented. Instead of true, primary, idiopathic schizophrenia, a diagnosis of secondary schizophrenia (pseudo-schizophrenia or schizophrenia-like psychosis) was made, corresponding to a secondary psychotic syndrome, with hallucinations and delusions due to congenital cavum septi pellucidi, cavum vergae, cavum veli interpositi and progressive brain atrophy due to cystinosis. Extreme caution is recommended when diagnosing schizophrenia in severely psychotic patients independent of their acute or chronic condition. Schizophrenia shall never be forgotten as the great imitated of medicine.

Interventions to address impostor phenomenon: a scoping review protocol

OBJECTIVE

This scoping review will identify and map the literature on interventions to address impostor phenomenon.

INTRODUCTION

Impostor phenomenon, also known as Impostor syndrome, describes intense feelings of fraudulence and chronic self-doubt. The phenomenon has been associated with a range of psychological issues and has been linked to negative career outcomes. While research on the prevalence of impostor phenomenon and its associated comorbidities has been reported for over 40 years, there is a paucity of studies that describe interventions to address this phenomenon.

INCLUSION CRITERIA

The review will consider any English-language study that describes or evaluates interventions to mitigate impostor phenomenon. Quantitative and qualitative studies will be sourced from published literature, gray literature, and the references of retrieved articles. Studies will not be limited by participant or setting. Authors of primary studies will be contacted to identify additional sources or for clarifications, where required. Conference abstracts, editorials, and opinion papers will be excluded.

METHODS

Databases to be searched will include APA PsycNet, MEDLINE, Scopus, and Web of Science. All databases will be searched from inception till the present. Retrieved citations will be independently reviewed by the reviewers, and relevant studies will be extracted using a data extraction form developed for this review. The results will be presented in tabular format and accompanied by a narrative summary. The review will be conducted in accordance with the JBI guidelines for scoping reviews.

SCOPING REVIEW REGISTRATION

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Capgras Syndrome: In the Conscious and the Unconscious Mind: A Case Report

We report the successful psychotherapy and medical treatment of a patient with an atypical presentation of Capgras syndrome, in which the patient not only believed that his parents were impostors but also believed that the entirety of what others would consider consensual reality was in fact an impostor. He insisted that a complex delusional world in which he wished to reside was authentic reality. His delusions of misidentification waxed and waned in response to discernable social stressors, and at times, he seemed to have conscious insight into the delusional nature of his beliefs. This case raises questions about whether Capgras should be considered a stand-alone diagnosis or whether it should be placed within a wider spectrum of psychotic disorders. Excepting our current report, although there are numerous reports of the resolution of Capgras after treatment with neuroleptics, we are unaware of descriptions in the literature of the successful treatment of medication-resistant Capgras with a combination of individual psychotherapy and pharmacological management.

Neuropsychiatric Features of Fregoli Syndrome: An Individual Patient Meta-Analysis

OBJECTIVE

Fregoli syndrome is a rare delusion characterized by the belief that familiar people are presenting themselves disguised as others to the affected person. Theories of delusional misidentification have suggested secondary ("organic") underlying mechanisms; however, the pathoetiology of Fregoli syndrome has not been systematically evaluated. The investigators aimed to compare the neuropsychiatric features of Fregoli syndrome in primary and secondary psychoses.

METHODS

A systematic review and patient-level meta-analysis were conducted. Five databases were searched, ultimately yielding 83 studies that met selection criteria. Demographic characteristics, diagnosis, delusional content, neuropsychiatric features, investigations, and treatment information were extracted. Random-effects models were calculated, and odds ratios (ORs) and 95% confidence intervals (CIs) were estimated.

RESULTS

A total of 119 patients with Fregoli syndrome were identified: 62 patients (52%) with primary psychosis, 50 (42%) with secondary psychosis, and seven (6%) with an unclear etiology. Patients with secondary psychosis were less likely than patients with primary psychosis to experience persecutory features (OR=0.26, 95% CI=0.10, 0.67; p=0.0057). Moreover, patients with secondary psychosis were more likely to experience Fregoli syndrome during a first episode of psychosis (OR=11.00, 95% CI=2.45, 49.39; p=0.0017). Right-sided brain lesions were more prominent than left-sided brain lesions in the total sample (χ²=5.0, df=1, p=0.025) and in the secondary psychosis subgroup (χ²=4.26, df=1, p=0.039).

CONCLUSIONS

This is the first meta-analysis to investigate Fregoli syndrome. An estimated 42% of the reported cases involved a secondary etiology. These findings provide clinicians with a better understanding of the symptomatology of Fregoli syndrome and have potential to be applied in future research and clinical practice.

Capgras Syndrome as the Core Manifestation of Early-Onset Alzheimer’s Disease

Capgras syndrome (CS) was usually considered a symptom of a functional disorder in the young, most commonly schizophrenia, or an organic disorder in the elderly. The occurrence of CS among early-onset Alzheimer’s disease (EOAD) is extremely rare. We describe a case in which the unrecognition of CS as part of EOAD resulted in a wrong psychiatric diagnosis and inappropriate treatment. This paper aims to acknowledge CS as an early or core manifestation and highlight EOAD as a differential diagnosis of mental disorders in young people, even without a remarkable family history.

Capgras Syndrome Due to Cannabinoids Use: A Case Report With Radiological Findings

Capgras syndrome is a part of the delusional misidentification syndromes. In this condition, the patient believes that identical individuals have impersonated the people close to them, leading to aggression or even homicide of their relatives. The following article describes the case of a 28-year-old patient with a history of cannabis consumption who arrived at the emergency department due to an unsuccessful murder attempt against his neighbor. At the mental examination, the patient believed their parents were killed some time ago, and impostors were replacing them; laboratory tests showed tetrahydrocannabinol in the urine sample. Therefore, the diagnosis of Capgras syndrome due to cannabis consumption was performed, and treatment was established with two antipsychotics and one mood stabilizer drug, showing satisfactory results after two months.

What is Capgras delusion?

INTRODUCTION

Capgras delusion is sometimes defined as believing that close relatives have been replaced by strangers. But such replacement beliefs also occur in response to encountering an acquaintance, or the voice of a familiar person, or a pet, or some personal possession. All five scenarios involve believing something familiar has been replaced by something unfamiliar.

METHODS

We evaluate the proposal that these five kinds of delusional belief should count as subtypes of the same delusion.

RESULTS

Personally familiar stimuli activate the sympathetic nervous system (SNS) much more strongly than unfamiliar stimuli. In Capgras delusion, this difference is absent, prompting the delusional idea that a familiar person is actually a stranger. We suggest this absence of an effect of familiarity on SNS response will occur in all five scenarios and will prompt the idea that the familiar has been replaced by the unfamiliar.

CONCLUSIONS

We propose that: (a) all five scenarios be referred to as subtypes of Capgras delusion; (b) in all five, ideas about replacement are prompted by weakness of SNS responses to familiar stimuli; (c) this is insufficient to generate delusion. For a delusional idea to become a belief, a second factor (impaired hypothesis evaluation) must also be present.

Coexistence of Different Delusional Misidentification Syndromes in Clinical Practice: A Case Series

OBJECTIVE

The objective of this study is to analyse the coexistence of several delusional misidentification syndromes in a clinical sample.

METHODS

Over one year, a sample of six patients presenting two or more types of delusional misidentification syndromes was selected. All these patients were admitted to the psychiatric inpatient unit of a Spanish hospital.

RESULTS

Despite the different diagnoses, the patients included presented different types of delusional misidentification syndromes, both hyperidentification and hypoidentification. Antipsychotic treatment was not very effective against these delusional misidentification syndromes CONCLUSIONS: The coexistence of several delusional misidentification syndromes indicates that the aetiopathogenesis of the different types is similar. It is a field with important clinical implications, due to the poor response to treatment, as well as the possible medico-legal implications.

Delusional misidentification syndrome and criminal acting out: A case report of maternal filicide

Delusional misidentification syndromes are associated with danger and may lead to homicide. Early assessment of the danger is a key part of the psychiatric examination. Compliance to treatment in psychosis is important to avoid the devastating consequences, for the perpetrator, the victim, and the community.

Epileptic Capgras-Like Delusions in a Patient with Right Frontal Meningioma: Case Report

Capgras syndrome is a condition characterized by the belief that a relative has been replaced by an almost identical imposter. The disorder has been reported in several neurological diseases. We describe the uncommon case of a transient Capgras syndrome manifesting as focal temporal seizures in a woman with a right frontal meningioma. Our patient represents an exceptional case of Capgras syndrome for several reasons, namely, the association with meningioma, very rarely reported before, the transient manifestation of symptoms, and, most importantly, the epileptic etiology of reduplicative paramnesias. Lastly, our report also confirms the importance of frontal and right hemisphere dysfunction in generating Capgras syndrome-like delusions.

Capgras delusion in postpartum psychosis: a case report

BACKGROUND

Capgras delusion is one of the delusional misidentification syndromes characterized by the belief by the patient that the close person is replaced by an imposter who looks physically the same. It rarely occurs in Postpartum Psychosis. An intriguing phenomenon with ongoing debates, particularly about its feature and prevalence, its course, occurrence, and phenomenon in the postpartum period are poorly understood.

CASE PRESENTATION

A 26-year-old Nepalese woman presented to the emergency for abnormal behavior on her 9th postpartum day. Capgras delusion was observed for 2 days during her hospital stay. Other psychotic symptoms appeared progressively and were treated as a case of Postpartum Psychosis.

CONCLUSION

This case describes the temporal sequence of various psychopathologies during Postpartum Psychosis including Capgras delusion. We attempt to explain the occurrence of Capgras delusion in Postpartum Psychosis.

A Rare Case of Capgras Syndrome in Moyamoya Disease

Moyamoya disease is a rare cerebrovascular disorder with unknown etiology and psychiatric symptoms occasionally manifest initially. Capgras syndrome is a unique neuropsychiatric symptom that is a delusional misidentification of a familiar person replaced by an identical imposter. We report the case of a 51-year-old woman with frontal lobe ischemic stroke caused by moyamoya disease, presenting with Capgras syndrome. Dysfunction of frontal areas may be attributable to development of Capgras syndrome.

[Delusional Misidentification Syndrom and Violent Behavior - Risk Assessment and Management]

OBJECTIVE AND METHOD

A case series of three patients with Delusional Misidentification Syndroms (DMS) and violent behavior is presented with respect to the correlation between DMS and violence as well as to the management of such occurrences.

RESULTS AND CONCLUSION

DMS could be one of the reasons for violent behavior of patients with psychiatric disorders. In such case violent behavior is not just restricted to intimates and relatives but also turns on non-familiar caregivers. DMS could be a risk factor for violent behavior and should therefore be registered with help of a nuanced psychopathological exploration at the time of clinical admission and in course of treatment. Moreover risk assessment tools and safety measures (e. g. medication, monitoring) could be considered for patients with DMS.

Catching the imposter in the brain: The case of Capgras delusion

Here we describe a rare case of Capgras delusion - a misidentification syndrome characterized by the belief that a person has been replaced by an imposter - in a patient without evident neurological or psychiatric symptoms. Intriguingly, delusional belief was selective for both person and modality, as the patient believed that his son - not his daughter or other relatives - was substituted with an imposter only while being in presence of him and looking at his face, but not when merely listening to his voice. A neuroanatomical reconstruction obtained integrating morphological and functional patient's neuroimaging data highlighted two main peculiarities: a compression of the rostral portion of right temporal lobe due to a large arachnoid cyst, and a bilaterally reduced metabolism of frontal areas. Autonomic data obtained from thermal infra-red camera and skin conductance recordings showed that a higher sympathetic activation was evoked by the observation of daughter's face, relative to the observation of the son's face as well as of not-familiar faces; conversely, daughter and son voices elicited a similar sympathetic activation, higher relative to not-familiar voices, indicating a modality-dependent dissociation consistent with the delusional behavior. Our case supports the "two-hit hypothesis" about Capgras delusion etiopathogenesis: here, the first hit is represented by the right-temporal lesion impairing the association between familiar faces and emotional values, the second one is the frontal bilateral hypometabolism favoring delusional behavior. The selective occurrence of "imposter" delusion for a particular subject and for a specific perceptual modality suggests the involvement of modality-specific interactions in the retrieval of affective properties during familiar people recognition.