Capgras syndrome is a disorder of personal identification characterized by the delusional belief that one or more persons close to the subject have been replaced by physically identical doubles.

To deepen our knowledge of the Capgras syndrome

A case report about a Capgras syndrome.

We report the case of a 46-year-old female patient who was admitted in February 2021 for incoherent speech and behavior disorder against her family members. Three years ago, she started to have hypochondriacal concerns. A week before her admission, she threatened her husband with a knife and she was convinced that her daughters were dead and that they had been replaced by clowns. She had a Capgras delusion with a hallucinatory and interpretative mechanism against her daughters, she reported olfactory and cenesthetic hallucinations. Biological explorations and brain CT were normal. The PANNS scale showed a positive scale of 36, a negative scale of 39, the general psychopathology scale of 53. She had a total score of 30/40 on The Penn emotion recognition test. The patient had difficulty in recognizing low intensity emotions (0 or 1) and 50% of the false responses were for the neutral emotion with responses tending towards anger first and then sadness.

Capgras syndrome remains poorly described in the literature and the hypotheses concerning its origin often oscillate between neuropsychological and psychodynamic. With the recent advances in neuroscience, it would be interesting to deepen its physiopathology in order to place it in a more modern nosological framework.

No significant relationships.

Capgras syndrome, where patients have the conviction that one or more close people have been replaced by a “double,” is the most prevalent delusional misidentification syndrome. It appears in psychiatric illness and organic brain damage. It seems to be due to damage of bifrontal and right limbic and temporal regions, mainly in the right hemisphere.

To review the pathologies associated to Capgras Syndrome and the relevance of the differential diagnosis

53-year-old female was admitted due to great sadness, crying, social withdrawal and severe paranoid concerns over the last month. Follow-up in Mental Health since 2014, because of anxious depression. After her mother’s death, she felt being followed because of old faults. Since then, low dosis of antipsychotics were used. Now she is afraid of being harmed in relation to petty thefts she committed over 15 years ago. In recent days, she has been noticing small details indicating that her family members have been impersonated by strangers, showing anguish regarding their whereabouts.

During her admission, high doses of antidepresants and paliperidone 6 mg/day were used with the complete disappearance of Capgras Syndrome and her anguish. Mild guilty thoughts were present after her discharge. That is why she was diagnosed with psychotic depression.

Capgras syndrome can be encountered in primary psychiatric diagnosis (particularly in schizophrenia and mood disorders) – where an organic element may exist in about a third of all cases – or secondary to organic disorders or medication-induced, through to overt organic brain damage, particularly in neurodegenerative disease.

Capgras syndrome is the most common type of delusional misidentification syndromes. In this phenomenon, the patient believes the delusional conviction that a familiar person has been replaced by imposters. Capgras syndrome was thought to occur in psychotic and organic contexts. It has some rare variants. In one of these rare variants, the patient has the delusion of inanimate doubles. There are reports which regard the relationship between Capgras syndrome and epilepsy as a contributing factor. We present a case of grandmal epilepsy with psychotic features including delusion of inanimate doubles.

A single case is reported.

A 55-year-old woman with long-time history of grandmal epilepsy developed psychosis 3 months prior to her psychiatric referral. She believed that her sons replaced her possessions and furniture continuously. There was no history of previous psychiatric illness, and also there was no evidence of any other organic disorder.

Previous reports showed Capgras phenomenon as a clinical presentation in epileptic patients. We show that the delusion of doubles of inanimate objects as a variant of Capgras syndrome could also be a clinical presentation in epileptic patients.

Capgras syndrome (CS), the most common type of delusional misidentification syndrome, is the delusional belief that significant people in the patient's life have been replaced by identical doubles. Capgras syndrome is thought to be a rare syndrome which commonly occurs in a psychotic context.

The objective of this study was to estimate the 5-year prevalence rate of CS in a university hospital in-patient setting and determine associated etiological and sociodemographic factors.

All patient files and medical records were reviewed in detail for the presence of Capgras syndrome. The sociodemographic variables, clinical manifestations, and psychiatric and medical diagnoses of patients who fulfilled clinical criteria for Capgras syndrome were recorded for statistical evaluation.

The retrospective evaluation of patient files in 920 cases admitted to our psychiatric in-patient unit over 5 years revealed that 12 patients fulfilled the criteria for Capgras syndrome. The crude prevalence of Capgras syndrome in this population during 5-year period was 1.3% (1.8% for females, 0.9% for males). Schizophrenia (50%) was the most common psychiatric diagnosis in these patients. Only two patients presented with an organic etiology underlying Capgras syndrome.

The results of this study indicate that Capgras syndrome is not a rare syndrome, and commonly occurs during the course of either functional or organic psychotic illness. Age seems to be an important predicting factor for the etiology of psychosis underlying Capgras syndrome.