FDG-PET in Cotard syndrome before and after treatment: can functional brain imaging support a two-factor hypothesis of nihilistic delusions?

Autoimmune psychosis: Psychopathological patterns and outcome after immunotherapy

BACKGROUND

The diagnostic criteria for "autoimmune psychosis" have been proposed to identify patients presenting with psychotic symptoms of autoimmune origin. Here, we aim to characterize the psychopathological features and outcomes of patients diagnosed with autoimmune psychosis.

METHODS

We describe a cohort study conducted at the National Institute of Neurology and Neurosurgery of Mexico, including patients with psychotic symptoms exhibiting features of possible autoimmune psychosis: a) catatonia, b) dyskinesia, c) seizures, d) signs of neuroleptic malignant syndrome or clinical worsening after use of antipsychotics, or e) severe cognitive impairment.

RESULTS

Of 195 psychotic patients under assessment, 164 patients were diagnosed as having psychosis of autoimmune origin and received immunotherapy. Hallucinations were present in 83 %, delusions in 77 %, and disorganized speech in 64 % of the cases. Severe cognitive dysfunction was present in 75 % while 64 % were diagnosed with catatonia. Seizures were the most common neurological feature (63 %), followed by movement disorders and autonomic abnormalities. Most patients (71%) were diagnosed as having definite anti- NMDAR encephalitis. A significant proportion of the cases (39 %) had been previously misdiagnosed as having a primary psychiatric disorder. After immunotherapy, most patients with anti-NMDA receptor encephalitis, or with a negative determination of NMDA receptor antibodies, experienced cognitive and functional improvement, and a significant reduction in psychotic symptoms.

CONCLUSIONS

Our study supports previous observations about the value of the autoimmune psychosis construct, the pleomorphic psychopathological patterns of autoimmune encephalitis, and the significant improvement of psychopathology after immunotherapy.

Cotard's: a controlled single case study of putative perceptual, cognitive and psychological risk factors

This case study explores the psychological and neuropsychological traits of a 55-year-old woman, D.R., who has Cotard's, believing her torso has dissolved and food bypasses her legs. Her delusion emerged amid major depressive disorder with psychotic features, following prodromal symptoms like body distortion and somatosensory abnormalities. A neuropsychological assessment during remission revealed low-level visual perceptual deficits in an otherwise intact cognitive profile. Subtle distortions in bodily signals and specific attribution styles were identified as vulnerability factors, suggesting that the delusion may emerge when already strained information processing systems are further challenged. This relates to models of delusion formation.

A working model of neural activity and phenomenal experience in psychosis

According to classical phenomenology, phenomenal experience is composed of perceptions (related to environmental stimuli) and imagery/ideas (unrelated to environmental stimuli). Intensity/vividness is supposed to represent the key phenomenal difference between perceptions and ideas, higher in perceptions than ideas, and thus the core subjective criterion to distinguish reality from imagination. At a neural level, phenomenal experience is related to brain activity in the sensory areas, driven by receptor stimulation (underlying perception) or associative areas (underlying imagery/ideas). An alteration of the phenomenal experience that leads to a loss of contact with reality characterizes psychosis, which mainly consists of hallucinations (false perceptions) and delusions (fixed ideas). According to the current data on their neural correlates across subclinical conditions and different neuropsychiatric disorders (such as schizophrenia), hallucinations are mainly associated with: transient (modality-specific) activations of sensory cortices (primarily superior temporal gyrus, occipito-temporal cortex, postcentral gyrus, and insula) during the hallucinatory experience; increased intrinsic activity/connectivity of associative/default-mode network (DMN) areas (primarily temporoparietal junction, posterior cingulate cortex, and medial prefrontal cortex); and deficits in the sensory systems. Analogously, delusions are mainly associated with increased intrinsic activity/connectivity of associative/DMN areas (primarily medial prefrontal cortex). Integrating these data into our three-dimensional model of neural activity and phenomenal-behavioral patterns, we propose the following model of psychosis. A functional/structural deficit in the sensory systems complemented by a functional reconfiguration of intrinsic brain activity favoring hyperactivity of associative/DMN areas may drive neuronal activations in the sensory (auditory/visual/somatosensory) areas and insular (interoceptive) areas with spatiotemporal configurations maximally independent from environmental stimuli and predominantly related to associative processing. This manifests in perception deficit and imagery/ideas composed of exteroceptive-like and interoceptive/affective-like elements that show a phenomenal intensity indistinguishable from perceptions, impairing the reality monitoring, along with minimal changeability by environmental stimuli, ultimately resulting in dissociation of the phenomenal experience from the environment, i.e., psychosis.

The Cotard Delusion in a Patient With Neuropsychiatric Systemic Lupus Erythematosus: The Challenges of Autoimmune Psychosis

The clinical features of neuropsychiatric systemic lupus erythematosus (NPSLE) are heterogeneous. Furthermore, therapeutic decision-making for NPSLE depends on the recognition of clinical syndromes that have not been sufficiently studied. This report describes the case of a 36-year-old woman with NPSLE who exhibited severe cognitive dysfunction and affective psychosis with persistent nihilistic delusions such as those described in the Cotard delusion. The patient insisted for several months that she was already dead. CSF analysis showed elevated levels of anti-ribosomal P antibodies and a positive determination of oligoclonal bands. Additionally, 18F -FDG PET/CT imaging revealed severe bilateral frontal hypermetabolism suggestive of brain inflammation and occipital hypometabolism. Results from the Systematic Lupus Erythematosus Disease Activity Index 2000 and the Systemic Lupus Erythematosus Disease Activity Score were consistent with an active state of the immunological disease. We then determined by an algorithm that this neuropsychiatric event could be attributed to the activity of the underlying immunological disease. Despite immunosuppressive and symptomatic treatment, only a partial improvement in cognition was achieved. The psychopathological features of the Cotard delusion remained unchanged 4 months after onset. However, we observed rapid remission of affective psychosis and significant improvement in cognition following electroconvulsive therapy. Subsequent follow-up examinations showed a sustained remission. This case describes a protracted form of the Cotard delusion, the diagnostic challenges that arise in the context of SLE, and treatment dilemmas that necessitate collaboration between neurology, psychiatry, and rheumatology.

Longitudinal Changes of Regional Cerebral Blood Flow on a Single-Photon Emission Computed Tomography (SPECT) Scan in a Patient With Schizophrenia Having Cotard's Syndrome

Cotard's syndrome is a rare clinical condition characterized by the presence of nihilistic delusions, delusions of immortality, depressive mood, and anxiety. Longitudinal changes in regional cerebral blood flow (rCBF) obtained under different conditions with and without Cotard's syndrome have rarely been reported in the literature. We report a case of a patient with Cotard's syndrome in whom longitudinal rCBF was assessed using single-photon emission computed tomography (SPECT). The patient was a 52-year-old man suffering from schizophrenia and mild mental retardation. He was transported to our hospital because of lumbar fractures caused by a suicidal attempt. In the second week after admission, he displayed Cotard's syndrome, i.e., nihilistic delusions, suicidal thoughts, and depressive mood. SPECT with 99mTc-ethyl cysteinate dimer was performed, and the rCBF increased in the bilateral prefrontal cortex but decreased in the occipital and parietal lobes. He was treated with pharmacotherapy mainly using lurasidone, and his Cotard's symptoms disappeared. SPECT was performed again. The increased rCBF in the bilateral prefrontal cortex and the decreased rCBF in the right occipital and parietal lobes were improved. The present case suggests that increased rCBF in the prefrontal cortex and decreased rCBF in the right occipital and parietal lobes are associated with the development of Cotard's syndrome.

Case report: A case of anti-recoverin antibody-positive encephalitis exhibiting Cotard and Capgras delusions that was successfully treated with electroconvulsive therapy

Recoverin is a neuron-specific calcium-binding protein that is mainly located in the retina and pineal gland. Few reports have described patients with anti-recoverin antibody-positive encephalitis, and no cases of psychosis associated with this encephalitis have been reported. We report a patient with anti-recoverin antibody-positive encephalitis with Cotard and Capgras delusions who was successfully treated with electroconvulsive therapy (ECT). The patient was a 25-year-old woman. She exhibited disorientation, executive function deficits, tremors in the upper limbs, generalized athetoid-like involuntary movements, hallucinations, incontinence, and fever, which led to her admission to our hospital. Upon admission, she complained of Cotard delusions. Various diagnostic tests, including cerebrospinal fluid analysis, antibody screening, and brain imaging, were unremarkable, except for positivity for serum anti-recoverin antibodies, non-specific general slowing on electroencephalography and decreased regional cerebral blood flow (rCBF) in the frontal and occipital lobes, and increased rCBF in the basal ganglia and pons on single-photon emission computed tomography. She was eventually diagnosed with encephalitis positive for anti-recoverin antibodies and treated with immunoglobulins and steroids. Her neurological symptoms improved temporarily, but three months later, psychiatric symptoms, i.e., suicidal thoughts and Cotard and Capgras delusions, were exaggerated. After ECT, her condition significantly improved. In conclusion, the present report suggests that pineal gland dysfunction due to anti-recoverin antibody or its cross-reactivity with neuron-specific calcium-binding proteins may contribute to the neuropsychiatric symptoms observed in anti-recoverin antibody-positive encephalitis and that ECT can be a viable treatment option if immunotherapy proves ineffective. Additionally, decreased rCBF in the prefrontal cortex may be associated with the clinical features of Capgras and Cotard delusions.

You are already dead: Case report of nihilistic delusions regarding others as one representation of Cotard's syndrome

Background

While the symptom of "I am already dead" is a hallmark of Cotard's syndrome, also known as nihilistic delusions, the symptom of "you are already dead" has been neglected.

Case presentation

A woman aged in her 60s diagnosed with schizophrenia was admitted to our hospital for psychotic symptoms, including delusions of reference, delusions of guilt, auditory hallucinations, cenesthetic hallucinations, agitation, depression, suicidal ideation, and catatonia. During hospitalization, her cenesthetic hallucinations progressed to include nihilistic delusions. She described cenesthetic hallucinations along with various delusional descriptions, including the belief that various objects, such as spoons, irons, nails, rulers, bins, and coins, were inside her body and that her body was being burned or in danger of exploding. She also claimed an altered sense of her own body, that her body was larger than normal or reversed. Moreover, she reported nihilistic delusions that her face and body did not exist, that her heart was not functioning, and that she was going to die soon or was already dead. She occasionally refused to eat because of the feeling of being dead. Notably, during a severe episode, she claimed that a doctor in front of her was dead. Clozapine was effective in improving her symptoms. Ultimately, the patient regained her sense of being alive and acknowledged that the doctor was alive.

Conclusion

We report the case of a patient presenting with nihilistic delusions regarding both self and others, along with prior cenesthetic hallucinations. Aberrant interoceptive processing could be a potential link between these two forms of nihilistic delusions.

Cotard delusion, emotional experience and depersonalisation

INTRODUCTION

Cotard delusion-the delusional belief "I am dead"-is named after the French psychiatrist who first described it: Jules Cotard. Ramachandran and Blakeslee proposed that the idea "I am dead" comes to mind when a neuropathological condition has resulted in complete abolition of emotional responsivity to the world. The idea would arise as a putative explanation: if "I am dead" were true, there would be no emotional responsivity to the world.

METHODS

We scrutinised the literature on people who expressed the delusional belief "I am dead", looking for data on whether such patients are reported as entirely lacking in emotional responsivity.

RESULTS

In numerous cases, patients with Cotard delusion are described as experiencing emotions including anxiety, fear, guilt, distress, euphoria and worry.

CONCLUSIONS

We conclude that complete absence of emotional responsivity cannot be what prompts the delusional idea that one is dead. We propose that, in at least some cases, the idea "I am dead" comes to mind in response to symptoms of depersonalisation or derealisation, often present in cases of Cotard delusion, and give examples of Cotard patients with abnormalities in various neural areas that could be responsible for the presence of such symptoms.

A medical algorithm for Cotard delusion based on more than 300 literature cases

OBJECTIVE

Cotard delusion (CD) is a rare psychiatric disorder in which the patient believes to be dead, i.e., the patient holds nihilistic delusions concerning his/her own existence. Taking into account its rarity, and possible subdiagnosis due to unawareness, most of the literature consists of case studies, complicating a more systematic approach and leading to difficulties in deciding the best clinical guidance to offer the patient suffering from CD. The objective of this work is to review the literature and propose an algorithm to help the differential diagnosis and the management of this condition.

METHOD

To do so, an extensive literature research was performed using several bibliographic databases. Since data on this topic is scarce, references in every article were cross-checked, aiming to obtain all available peer-reviewed works on CD.

RESULTS

Research resulted in 328 cases. Several treatment modalities were reported to improve the symptoms of CD, from pharmacotherapy - mainly consisting of antipsychotics and antidepressants - to electroconvulsive therapy.

CONCLUSIONS

Despite its challenging diagnosis, the delusion can be treated with readily available care. Hopefully, this work can be a useful tool to doctors when encountering this odd affliction.

Cotard parasomnia: le délire de negation that occur during the sleep-wake dissociation?

None

Unpleasant dreamlike mentation can occur during non-rapid eye movement parasomnias, leading to associated panic attacks. The mentations are rarely remembered and are likely underreported. However, they may lead to significant personal distress and, if not addressed, may contribute to poorer clinical outcomes. Cotard le délire de negation are very rare nihilistic delusions, historically described with psychotic disorders. Their association with a variety of neurologic disorders, including migraine and cluster-headache, has also been reported. Here we present three cases of Cotard parasomnia during which distinct states of consciousness defined by nihilistic ideation occurred. Patients described believing they are dead or dying, while unable to perceive or experience their bodies in whole, or in part, as their own. A source analysis of the electroencephalographic fingerprint of these mentations suggests right-hemispheric hypoactivity subsequent to confusional arousals. Mechanistically, an aberrant activation of two major intrinsic brain networks of wakefulness, the salience network and the default mode network, is argued.

Cotard syndrome in anti-NMDAR encephalitis: two patients and insights from molecular imaging

Cotard syndrome is a clinical condition defined by the presence of nihilistic delusions. We report two patients with Cotard syndrome in whom anti-NMDAR encephalitis (ANMDARE) was confirmed. Both cases showed features of affective psychosis, developed catatonic syndrome, and worsened after the use of antipsychotics. 18F-FDG PET brain studies showed a bilateral hemispheric pattern of hypometabolism in posterior regions, mainly in the cingulate cortex and in the medial aspects of parietal and occipital lobes. A more severe hypometabolism was observed in the right hemisphere of both patients. Both cases remitted with the use of specific immunotherapy for ANMDARE.

Anton syndrome after subarachnoid hemorrhage and delayed cerebral ischemia: A case report

•

Bilateral occipital damage is not sufficient for the onset of visual anosognosia.

•

Anton syndrome may result from bilateral occipital and right frontoparietal lesions.

•

Anosognosia can be understood as a metacognitive deficit.

•

Disturbed metacognition is related to right fronto-parietal dysfunction.

•

Delusions of being dead (Cotard syndrome) may appear after right hemispheric damage.

We report the case of a patient with ruptured middle cerebral artery aneurysm, subarachnoid hemorrhage and frontal intracerebral hemorrhage, who secondarily presented with delayed cerebral ischemia and bilateral occipital infarcts, with complete vision loss, visual anosognosia, and confabulations as the main symptoms. Additionally, the patient had defined features of Cotard syndrome, as revealed by persistent nihilistic delusions. The brain imaging studies showed a bilateral occipital ischemic lesion, as well as frontal and parietal hemorrhagic lesions in the right hemisphere. We address the general theories of anosognosia, confabulation and the problem of why a bilateral occipital lesion is not enough for these metacognitive defects to exist. The presence of right frontal and or parietal hemisphere lesions could be necessary features in most cases.

The 'dead man walking' disorder: an update on Cotard's syndrome

In 1880, Jules Cotard described a peculiar syndrome after observing the case of a 43-year-old woman, which was characterized by melancholic anxiety, delusions of damnation or possession, a higher propensity to suicide ideation and deliberate self-harm, analgesia, hypochondriac thoughts of non-existence or ruin of several organs, of the whole body, of the soul, of divinity, and the idea of immortality or inability to die. Several expansions and reinterpretations have been made of the so-called Cotard's syndrome, which is often encompassed in different neurological and psychiatric disorders, complicating and worsening their symptomatic frameworks and making more difficult their treatments. However, the nosographic characterization of Cotard's syndrome remains elusive and is not now classified as a separate disorder in both ICD and DSM-5. Here, we try to give an update, as well as a putative systematization, of current views and opinions about this nosological entity in the light of the recent progress in the clinic, psychopathology and psycho-neurobiology.