Phantom boarder symptom in elderly Japanese.

BACKGROUND: Phantom boarder symptom (PBS) is classified as a delusional misidentification syndrome, and is often encountered in elderly individuals who have mild or major neurocognitive disorders. With the ageing of society, patients presenting with PBS are increasing in Japan. This retrospective study was conducted to examine the aetiology and identify significant predictors of PBS. METHODS: The records of 511 consecutive patients who visited our hospital with suspicion of dementia between September 2013 and September 2019 were retrospectively examined. From those, 16 patients who presented with PBS (1 male, 15 females; mean age 79.9 ± 4 years) were selected and case features were investigated in detail. Clinical symptoms, background factors, and final diagnoses were noted. PBS was most common in patients affected by dementia with Lewy bodies (DLB). Predictive factors were evaluated using multiple logistic regression analysis. RESULTS: The final diagnosis of the 16 subjects was DLB in 7, Alzheimer's disease in 3, delusional disorder in 3, unspecified dementia in 2, and vascular dementia in 1. Analysis limited to DLB cases showed that a low Mini-Mental State Examination (MMSE) score and living alone were related to higher risk for PBS. CONCLUSION: Various types of dementia, especially DLB, as well as cognitive impairment and living alone were found to be strong predictors of PBS.

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 case of mirror image agnosia and mirrored self-misidentification syndrome in schizophrenia without dementia or structural abnormalities.

Delusional misidentification syndrome (DMS) is an umbrella term encompassing a variety of disorders. One rare form of DMS is the delusional misidentification of one's own reflection, known as "mirrored self-misidentification syndrome". In "mirror image agnosia", the ability to identify the image of self and/or others in the mirror is lost, while the ability to identify the mirror itself is preserved. To our knowledge, mirror image agnosia has never been described in a patient with schizophrenia. Herein we present a case of a patient with schizophrenia with severe delusions of both mirrored self-misidentification and mirror image agnosia without any structural abnormalities or dementia.

"Cat-gras" delusion: a unique misidentification syndrome and a novel explanation.

ABSRACT Capgras syndrome is a distressing delusion found in a variety of neurological and psychiatric diseases where a patient believes that a family member, friend, or loved one has been replaced by an imposter. Patients recognize the physical resemblance of a familiar acquaintance but feel that the identity of that person is no longer the same. Here we describe a 73-year-old male with right posterior frontal and bilateral anterior-medial frontal damage from prior brain trauma with a similar delusion of an imposter replacing his pet cat. Misidentification syndromes for animals, as opposed to humans, have been rarely reported. Neuropsychological testing showed deficits in executive processing and memory retrieval with prominent intrusions and false positive responses. The delusional belief content in Capgras syndrome has been hypothesized to result from loss of an emotional or autonomic response to familiar stimuli, from theory of mind deficits, or from loss of self-environment distinctions. We instead propose that Capgras delusions result from a dysfunction in linking external stimuli with retrieved internal autobiographical memories pertaining to that object. This leads to an erroneously learned identity that persists as a specific delusional belief.

An Unusual Presentation of Delusional Companion Syndrome: A Case Report and Review of the Literature.

Delusional companion syndrome, an uncommon subtype of delusional misidentification syndrome, has no prior reported cases in patients with primary psychotic disorders. We report a case of delusional companion syndrome in the absence of any organic brain disease, stroke, or severe brain injury, in a young female with schizophrenia. The patient is a 29-year-old G3P3 female, with a history of schizophrenia and major depressive disorder, who, after recently losing custody of her children, presented to the pediatric emergency department for evaluation of her baby doll, which she believed to be her child because the doll wasn't eating or moving well. She became acutely agitated when providers declined to insert an IV line to hydrate the doll and required emergency treatment orders to de-escalate. The patient was admitted to the inpatient psychiatric unit and treated with oral aripiprazole 10 mg, before transitioning to her previous treatment of aripiprazole lauroxil at an increased dose of 882 mg monthly. By the end of admission, the patient grasped that the doll was a toy that had never been alive. This case demonstrates how delusional companion syndrome can occur in young patients with primary psychotic disorders, without a causative neurological insult, and can be treated with antipsychotics. More studies are necessary to further explore the relationship between primary psychotic disorders and delusional companion syndrome.

Analysis of clinical characteristics of mirror and TV signs in Alzheimer's disease and dementia with Lewy bodies.

OBJECTIVE: This study explored the clinical features of dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) and analyzed the differences in neurologic syndromes, including mirror and TV signs, between different groups. METHODS: Patients with AD and DLB (325 and 115, respectively) hospitalized in our institution were enrolled. We compared psychiatric symptoms and neurologic syndromes between the DLB and AD groups and within each subgroup, including the mild-moderate and severe subgroups. RESULTS: The prevalence rates of visual hallucination, parkinsonism, rapid eye movement sleep behavior disorder, depression, delusion, and the Pisa sign were significantly higher in the DLB group than in the AD group. Furthermore, within the mild-moderate subgroup, the mirror sign and Pisa sign prevalence rates were significantly higher in the DLB group than in the AD group. In the severe subgroup, no significant difference was found in any neurologic sign between the DLB and AD groups. CONCLUSION: Mirror and TV signs are rare and often disregarded because they are not usually invoked during routine inpatient or outpatient interviews. According to our findings, the mirror sign is uncommon in early AD patients but common in early DLB patients and should receive increased attention.

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

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.

Clinical Lycanthropy, Neurobiology, Culture: A Systematic Review.

Background: Culture can affect psychiatric disorders. Clinical Lycanthropy is a rare syndrome, described since Antiquity, within which the patient has the delusional belief of turning into a wolf. Little is known on its clinical or therapeutic correlates. Methods: We conducted a systematic review (PRISMA) on PubMed and Google Scholar, until January 2021. Case reports, data on neurobiological hypotheses, and cultural aspects were included. Language was not restricted to English. Results: Forty-three cases of clinical lycanthropy and kynanthropy (delusion of dog transformation) were identified. Associated diagnoses were: schizophrenia, psychotic depression, bipolar disorder, and other psychotic disorders. Antipsychotic medication may be an efficient treatment for this rare transnosographic syndrome. In case of depression or mania, the treatment included antidepressants or mood regulators. The neuroscientific hypotheses include the conception of clinical lycanthropy as a cenesthopathy, as a delusional misidentification of the self-syndrome, as impairments of sensory integration, as impairments of the belief evaluation system, and right hemisphere anomalies. Interestingly, there is a clinical overlap between clinical lycanthropy and other delusional misidentification syndromes. Clinical lycanthropy may be a culture-bound syndrome that happens in the context of Western cultures, myths, and stories on werewolves, and today's exposure to these narratives on cultural media such as the internet and the series. We suggest the necessity of a cultural approach for these patients' clinical assessment, and a narrative and patient-centered care. Conclusions: Psychiatric transtheoretical reflections are needed for complementaristic neurobiological and cultural approaches of complex delusional syndromes such as clinical lycanthropy. Future research should include integrative frameworks.

Incidence and lesions causative of delusional misidentification syndrome after stroke.

OBJECTIVE: To better elucidate the symptomatology and pathophysiological mechanisms underlying delusional misidentification syndrome (DMS), we investigated the incidence rate and symptomatic features of DMS following stroke and relationships among DMS, other neuropsychological symptoms, and lesion locations. METHODS: The present study included 874 consecutive patients (371 women; mean age ± standard deviation = 72.2 ± 11.7 years) who were admitted to the rehabilitation wards at two hospitals within 2 months of their first stroke. We examined the clinical features and lesion sites of patients with DMS and compared them with those of a control group of patients with hemi-spatial neglect without DMS using voxel-based lesion-symptom mapping (VLSM). RESULTS: Among the 874 patients who experienced a stroke, we observed 10 cases of Fregoli syndrome. No other DMS subtypes were observed; however, eight patients exhibited somatoparaphrenia (five of them also had Fregoli syndrome) and one also exhibited reduplicative paramnesia. Right hemispheric lesions were found in all 10 cases. VLSM revealed statistically significant overlapping lesion sites specifically related to Fregoli syndrome when compared with the control group. The sites included the insula, inferior frontal lobe, anterior temporal lobe, and subcortical limbic system in the right hemisphere (i.e., areas connected by the uncinate fasciculus). CONCLUSION: The DMS incidence was 1.1% among patients after stroke. All patients had Fregoli syndrome and half had somatoparaphrenia, suggesting that the two syndromes share an underlying pathology. Lesions found with Fregoli syndrome were concentrated around the right uncinate fasciculus; this has not been reported in previous research.

Capgras Delusion in Posterior Cortical Atrophy-A Quantitative Multimodal Imaging Single Case Study.

Although Alzheimer's disease presents homogeneous histopathology, it causes several clinical phenotypes depending on brain regions involved. Beside the most abundant memory variant, several atypical variants exist. Among them posterior cortical atrophy (PCA) is associated with severe visuospatial/visuoperceptual deficits in the absence of significant primary ocular disease. Here, we report for the first time a case of Capgras delusion-a delusional misidentification syndrome, where patients think that familiar persons are replaced by identical "doubles" or an impostor-in a patient with PCA. The 57-year-old female patient was diagnosed with PCA and developed Capgras delusion 8 years after first symptoms. The patient did not recognize her husband, misidentified him as a stranger, and perceived him as a threat. Such misidentifications did not happen for other persons. Events could be interrupted by reassuring the husband's identity by the patient's female friend or children. We applied in-depth multimodal neuroimaging phenotyping and used single-subject voxel-based morphometry to identify atrophy changes specifically related to the development of the Capgras delusion. The latter, based on structural T1 magnetic resonance imaging, revealed progressive gray matter volume decline in occipital and temporoparietal areas, involving more the right than the left hemisphere, especially at the beginning. Correspondingly, the right fusiform gyrus was already affected by atrophy at baseline, whereas the left fusiform gyrus became involved in the further disease course. At baseline, glucose hypometabolism as measured by positron emission tomography (PET) with F18-fluorodesoxyglucose (FDG-PET) was evident in the parietooccipital cortex, more pronounced right-sided, and in the right frontotemporal cortex. Amyloid accumulation as assessed by PET with F18-florbetaben was found in the gray matter of the neocortex indicating underlying Alzheimer's disease. Appearance of the Capgras delusion was related to atrophy in the right posterior cingulate gyrus/precuneus, as well as right middle frontal gyrus/frontal eye field, supporting right frontal areas as particularly relevant for Capgras delusion. Atrophy in these regions respectively might affect the default mode and dorsal attention networks as shown by meta-analytical co-activation and resting state functional connectivity analyses. This case elucidates the brain-behavior relationship in PCA and Capgras delusion.

Prevalence and Clinical Implications of the Mirror and TV Signs in Advanced Alzheimer's Disease and Dementia with Lewy Bodies.

OBJECTIVE: To explore the prevalence and clinical implications of the mirror and TV signs in the moderate to advanced stages of Alzheimer's disease (AD) and dementia with Lewy bodies (DLB). METHODS: We retrospectively examined the prevalence of clinical and psychiatric symptoms including the mirror and TV signs in 200 subjects with AD and 200 with DLB and evaluated the relationships among the symptoms. RESULTS: The mirror sign was found in 3.0% of AD and 4.5% of DLB subjects. The TV sign was found in 1.5% of AD and 4.0% of DLB subjects. The prevalence of the mirror and TV signs was not significantly different between the AD and DLB groups. Visual hallucination, visual illusion, misidentification of person, and sleep talking were significantly more frequent in DLB than in AD subjects. The mirror sign was significantly associated with lower Mini-Mental State Examination scores, whereas the TV sign was significantly associated with the misidentification of person. CONCLUSIONS: Both the mirror and TV signs were rare even in the moderate to advanced stages of AD and DLB. The mirror sign may be independent from other delusional misidentification syndromes (DMSs). Being associated mainly with global cognitive decline, the mirror sign is unlikely attributed to any specific cognitive impairment or the dysfunction of localized brain areas. In contrast, the TV sign was significantly more often coexistent with the misidentification of person, suggesting that the TV sign may partly share common neuropsychological mechanisms with DMSs.

Capgras Syndrome in a Patient with Parkinson's Disease after Bilateral Subthalamic Nucleus Deep Brain Stimulation: A Case Report.

Capgras syndrome is a delusional misidentification syndrome (DMS) which can be seen in neurodegenerative diseases such as Lewy body dementia and, to a lesser extent, in Parkinson's disease (PD). Here, we report the case of a 78-year-old man with a history of idiopathic PD who developed Capgras syndrome following bilateral subthalamic nucleus deep brain stimulation (DBS) implantation. As the risk of DMS has been related to deficits in executive, memory, and visuospatial function preoperatively, this case highlights the importance of continuing to improve patient selection for DBS surgery. Capgras syndrome is a rare potential complication of DBS surgery in PD patients with preexisting cognitive decline.

Delusional misidentification syndromes and dementia: a border zone between neurology and psychiatry.

The delusional misidentification syndromes (DMSs) are psychopathologic phenomena in which a patient consistently misidentifies persons, places, objects, or events. Although often described in relation to psychotic states including schzofrenia, it is, nevertheless, widely considered that these syndromes have an anatomical basis because of their frequent association with organic brain disease; studies have pointed to the presence of identifiable lesions, especially in the right frontal lobe and adjacent regions, in a considerable proportion of patients. The purpose of this article is to examine the phenomenon in people with dementia. We searched the electronic databases for original research and review articles on DMS in patients with dementia using the search terms "Delusional Misidentification Syndrome, Capgras syndrome, Fregoli syndrome, reduplicative paramnesia, and dementia." The DMSs are a frequent problem in dementia. The violence and dangerousness in patients with dementia having these syndromes are well documented, and forensic aspects are highlighted. Pathogenetic viewpoint and management are considered.

Delusional misidentification secondary to perceptual abnormality: An unusual case of Capgras syndrome.

Capgras syndrome is the commonest of the delusional misidentification syndromes, occurring in 1 - 5% of psychotic patients. This case of a Capgras syndrome was secondary to an abnormal percept (auditory hallucination). Capgras syndrome is not a symptom specific to abnormalities of face recognition. ( Int J Psych Clin Pract 2000; 4: ).