INTRODUCTION
Delusions are false, fixed beliefs resistant to contrary evidence and disconnected from cultural norms [1]. They appear in various forms, such as the persecutory, soma-tic, or grandiose, and are common in schizophrenia and mood disorders, where they may differ in organization and mood congruence [1-3]. Delusions also occur in neurocognitive disorders like Alzheimer’s and Lewy body disease, or as secondary to brain injury, tumors, and substance use, with neuroimaging implicating the prefrontal and temporal regions in early psychosis [4, 5].
Delusional misidentification syndromes (DMS) are rare psychotic conditions where individuals misidentify people, places, or themselves. These may occur in psychiatric or organic contexts and include Capgras, Fregoli, intermetamorphosis, and others (Table 1) [6, 7]. DMS are often linked to right-sided frontal and temporal abnormalities and may follow trauma or neurological insults [8]. Capgras delusion has an estimated prevalence of 0.12% in the general population, increasing to about 1.3% among individuals with psychiatric disorders [9].
Table 1
Main delusional misidentification syndromes
This report describes a rare and severe variant of Capgras syndrome in a patient with schizophrenia, characterized by the belief that multiple familiar individuals had been replaced by numerous distinct imposters, an intensified and complex extension of the classical single- imposter presentation.
CASE DESCRIPTION
The patient is a 37-year-old male, secondary school graduate, formerly employed as a soldier by the military, currently unemployed, and divorced with one son. This marks his first psychiatric admission to our facility, although he previously received outpatient psychiatric care at a private clinic.
He was brought to the Emergency Department by his family and the police due to escalating aggression and overt psychotic symptoms. At presentation, he was severely psychotic, alleging his parents were impostors replaced up to 50 times, and accusing them of kidnapping and attempting to sell his son. He also expressed persecutory delusions involving Freemasonry and was minimally cooperative. His parents reported rising physical aggression, prompting police involvement.
During inpatient evaluation, the patient maintained the belief that his ex-wife had been replaced eight times by similar-looking women. He distinguished between them in terms of personality and body habitus, especially weight. These beliefs contributed to marital discord and eventual divorce after five years, which he attributed to manipulation by his cousins.
He also asserted that his mother is often replaced three times a day. In one instance, his siblings confirmed her identity, but the woman responded, “Your mother is dead.” He reported similar beliefs about his father who, he said, is regularly replaced twice a day, once by someone who sleeps all day and later by one who watches TV and does chores. When asked about his father’s identity, the response was again, “Your father is dead.” He claimed his siblings had been replaced 350 times.
Additionally, he believed one of his sons was real and the other an imposter distinguished by a scar on the arm. When asked how many children he had, he expressed uncertainty, citing multiple marriages. He strongly believed in his ability to identify impostors based on skin tone, personality, body shape, and other features, and planned to photograph family members after discharge as proof.
He also experienced persecutory delusions, claiming his family sent covert messages in order to drive him away from the home. He interpreted environmental cues, such as socks and fecal matter, as targeted provocations. He reported seeing soda-like stains on walls and curtains, which he attributed to magic or sorcery. These beliefs were accompanied by emotional distress, low mood, irri-tability, social withdrawal, and self-neglect. He felt betrayed and became increasingly isolated. He denied having hallucinations and showed no signs of mania, such as elation or a reduced need for sleep.
Regarding his psychiatric history, symptoms first emerged approximately eight years prior to presentation and progressed insidiously over the following years. During this period, family conflicts intensified, even-tually leading to the dissolution of his marriage after five years, and he subsequently lost his job. He was then evaluated at a private clinic, where he was diagnosed with schizophrenia and treated with quetiapine 200 mg and olanzapine 10 mg daily. Although he experienced partial improvement, his adherence was inconsistent, resulting in several relapses following a discontinuation of medication. Concerning substance use, he reported having used amphetamines (Captagon) daily for approximately two years, beginning about 15 years before his presentation to the hospital. He also reported past alcohol use when he spent time abroad. The urine drug screen on admission was negative.
His medical history included a cervical vertebral fixa-tion following a neck fracture seven years prior to our review and abdominal surgery due to obstruction five years prior. He had no complaints or history of chronic illnesses. Examination revealed only surgical scars. Family history revealed that two brothers had psychiatric diagnoses, including one of schizophrenia. According to the available history, the patient’s early development was unremarkable: he achieved normal developmental milestones, had no reported childhood behavioral or learning difficulties, and completed schooling without evidence of neurodevelopmental disorders.
His mental status examination at admission revealed a well-groomed adult male of average build. He was restless and minimally cooperative initially but improved during admission. He maintained eye contact and exhibited no hallucination-influenced behavior or abnormal movements. His mood ranged from euthymic to dysphoric, with reactive affect. His speech was coherent but occasionally disorganized. Thought content included delusions of persecution, misidentification (Capgras), and delusions of reference. Over time, reality testing and partial insight improved, and he began acknowledging past delusions. His thought process remained linear and goal directed. He consistently denied having hallucinations and was oriented to time, place, and person. Insight and judgment were initially poor but showed modest improvement.
Upon physical examination he was alert, hemodynamically stable, and had no significant abnormalities in his cardiovascular, respiratory, abdominal, or neurological systems. Laboratory tests, including complete blood count, kidney and liver panels, thyroid function, lipid profile, and glucose, were within normal limits. Electrocardiogram showed no abnormalities, and urine toxico-logy was negative. No acute medical issues were identified.
The patient was diagnosed with schizophrenia featuring prominent Capgras delusion after a full psychiatric evaluation. Emergency treatment consisted of single intramuscular doses of haloperidol 5 mg and diazepam 10 mg for acute agitation. During his inpatient stay, oral paliperidone (starting at 6 mg daily and gradually increased to 12 mg) was initiated, along with short-term lorazepam 1 mg PO as needed. He was subsequently transitioned to long-acting injectable paliperidone (150 mg IM as the initial loading dose, followed by 100 mg IM one week later) in accordance with the recommended initiation regimen. The patient demonstrated improved behavioral control and partial insight. Although he was discharged against medical advice, completion of the loading regimen was expected to provide continued antipsychotic coverage post-discharge.
DISCUSSION
Capgras delusion is a well-documented subtype of DMS, in which a person holds the belief that someone emotionally close to them, typically a spouse, parent, or child, has been replaced by an identical impostor. While this is most commonly observed as a single substitution, this case presents a rare elaboration involving the belief that multiple impostors have repeatedly replaced the same individual. This variant, though not classified as a separate entity, has been reported in the literature and represents a more complex manifestation of the misidentification phenomenon, likely shaped by the severity and chronicity of the underlying psychosis [6, 7].
A systematic review by Pandis, Agrawal, and Poole (2019), covering 255 published cases, found that while misidentification of multiple individuals was relatively common, the belief in serial substitution of a single person by multiple imposters was rare and almost exclusively associated with functional psychoses rather than organic brain disorders [10]. This differentiation has implications for both diagnosis and treatment. While psychotic Capgras might respond better to antipsychotics and cognitive restructuring, organic Capgras may warrant neuroimaging, cognitive support, and management of the underlying neurological condition.
In schizophrenia, misidentification delusions often occur alongside persecutory or referential beliefs, as demonstrated in our patient. He not only perceived his family members as impostors but also believed they were conspiring against him through psychological manipulation and supernatural means. This integration of misidentification with persecutory content is not uncommon and reflects broader cognitive distortions and impaired reality testing within psychotic disorders [1, 2, 4].
Neurobiological models of DMS suggest that these syndromes arise from a disconnection between intact facial recognition pathways and the affective response system. Specifically, lesions or functional disruptions in the right frontal and temporal lobes have been implicated in creating a mismatch between recognition and emotional familiarity, fostering the impression that a known person is somehow “not the same” [8, 11]. In more elaborate cases like ours, repeated misidentifications may result from further a breakdown in integrative cognitive- affective processes or secondary delusional elaboration, as is often seen in chronic psychosis.
The presence of DMS in schizophrenia is clinically important, as it is often associated with poor insight, greater chronicity, potential treatment resistance, and, in some cases, risk of aggression toward the supposed impostor [2, 3]. Management typically involves antipsychotic medication. In this case, the patient was initially managed with intramuscular haloperidol and diazepam to address acute agitation, followed by titrated oral paliperidone. Long-acting injectable paliperidone was introduced to ensure adherence to medication, an approach supported by evidence indicating improved outcomes in patients with poor insight and recurrent relapses.
From a nosological perspective, this case highlights the variability within Capgras presentations and underscores the importance of recognizing its more complex variants. Although no specific treatment guidelines exist for DMS, second-generation antipsychotics remain the standard of care, with cognitive-behavioral interventions as a possible adjunct in selected cases [1, 4].
This report is limited by the lack of neuroimaging or formal neuropsychological testing, which could have provided further insight into the underlying cognitive and anatomical correlates. However, neuroimaging was not insisted upon, as symptoms had been gradually evolving over eight years with an exacerbation of established illness, and neurological examination was unremarkable. Future studies should explore whether this multiple- impostor form of Capgras represents a distinct neuroco-gnitive subtype within schizophrenia and how it may relate to treatment response or prognosis. As a conclusion, this case highlights a rare and underrecognized variant of Capgras delusion. Such presentations underscore not only the complexity of misidentification phenomena within schizophrenia but also the importance of treatment strategies tailored to difficulties adherence. In particular, long-acting injectable antipsychotics and structured family psychoeducation may play a central role in improving outcomes and reducing the risk of relapse in similar cases.
