| Cotard's delusion | |
|---|---|
| Other names | Cotard's syndrome, Walking Corpse Syndrome |
 | |
| The neurologist Jules Cotard (1840–89) described "The Delirium of Negation" as a mental illness of varied severity. | |
| Specialty | Psychiatry |
Cotard's delusion, also known as walking corpse syndrome or Cotard's syndrome, is a rare mental disorder in which the affected person holds the delusional belief that they are dead, do not exist, are putrefying, or have lost their blood or internal organs. Statistical analysis of a hundred-patient cohort indicated that denial of self-existence is present in 45% of the cases of Cotard's syndrome; the other 55% of the patients presented with delusions of immortality.
In 1880, the neurologist Jules Cotard described the condition as Le délire des négations ("The Delirium of Negation"), a psychiatric syndrome of varied severity. A mild case is characterized by despair and self-loathing, while a severe case is characterized by intense delusions of negation and chronic psychiatric depression.
The case of Mademoiselle X describes a woman who denied the existence of parts of her body and of her need to eat. She said that she was condemned to eternal damnation and therefore could not die a natural death. In the course of suffering "The Delirium of Negation", Mademoiselle X died of starvation.
Cotard's delusion is not mentioned in either the Diagnostic and Statistical Manual of Mental Disorders (DSM) or the tenth edition of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) of the World Health Organization.
Signs and symptoms
Delusions
of negation are the central symptom in Cotard's syndrome. The patient
usually denies their own existence, the existence of a certain body
part, or the existence of a portion of their body. Cotard's syndrome
exists in three stages: (i) Germination stage: symptoms of psychotic depression and of hypochondria
appear; (ii) Blooming stage: full development of the syndrome and
delusions of negation; and (iii) Chronic stage: continued severe
delusions along with chronic psychiatric depression.
Cotard's syndrome withdraws the afflicted person from other
people due to neglect of their personal hygiene and physical health.
Delusions of negation of self prevent the patient from making sense of
external reality, which then produces a distorted view of the external
world. Such delusions of negation are usually found in schizophrenia.
Although a diagnosis of Cotard's syndrome does not require the
patient's having had hallucinations, the strong delusions of negation
are comparable to those found in schizophrenic patients.
Distorted reality
The article Betwixt Life and Death: Case Studies of the Cotard Delusion
(1996) describes a contemporary case of Cotard's delusion which
occurred in a Scotsman whose brain was damaged in a motorcycle accident:
[The patient's] symptoms occurred in the context of more general feelings of unreality and [of] being dead. In January 1990, after his discharge from hospital in Edinburgh, his mother took him to South Africa. He was convinced that he had been taken to Hell (which was confirmed by the heat) and that he had died of sepsis (which had been a risk early in his recovery), or perhaps from AIDS (he had read a story in The Scotsman about someone with AIDS who died from sepsis), or from an overdose of a yellow fever injection. He thought he had "borrowed [his] mother's spirit to show [him] around Hell" and that she was asleep in Scotland.
The article Recurrent Postictal Depression with Cotard Delusion (2005) describes the case of a fourteen-year-old epileptic boy who experienced Cotard syndrome after seizures. His mental health history was of a boy expressing themes of death, chronic sadness, decreased physical activity in playtime, social withdrawal, and disturbed biological functions.
About twice a year, the boy suffered episodes that lasted between
three weeks and three months. In the course of each episode, he said
that everyone and everything was dead (including trees), described
himself as a dead body, and warned that the world would be destroyed
within hours. Throughout the episode the boy showed no response to
pleasurable stimuli and had no interest in social activities.
Pathophysiology
Neural misfiring in the fusiform face area, in the fusiform gyrus (orange), might be a cause of the Cotard delusion.
In the cerebrum, organic lesions in the parietal lobe might cause the Cotard delusion.
The underlying neurophysiology and psychopathology
of Cotard syndrome might be related to problems of delusional
misidentification. Neurologically, Cotard's delusion (negation of the
Self) is thought to be related to Capgras delusion (people replaced by impostors); each type of delusion is thought to result from neural misfiring in the fusiform face area of the brain, which recognizes faces, and in the amygdalae, which associate emotions to a recognized face.
The neural disconnection creates in the patient a sense that the
face they are observing is not the face of the person to whom it
belongs; therefore, that face lacks the familiarity (recognition)
normally associated with it. This results in derealization
or a disconnection from the environment. If the observed face is that
of a person known to the patient, they experience that face as the face
of an impostor (Capgras delusion). If the patient sees their own face,
they might perceive no association between the face and their own sense
of self—which results in the patient believing that they do not exist (Cotard delusion).
Cotard's syndrome is usually encountered in people afflicted with psychosis, as in schizophrenia. It is also found in clinical depression, derealization, brain tumor, and migraine headaches. The medical literature indicate that the occurrence of Cotard's delusion is associated with lesions in the parietal lobe. As such, the Cotard's delusion patient presents a greater incidence of brain atrophy—especially of the median frontal lobe—than do people in control groups.
Cotard's delusion also has resulted from a patient's adverse physiological response to a drug (e.g., acyclovir) and to its prodrug precursor (e.g., valaciclovir). The occurrence of Cotard's delusion symptoms was associated with a high serum-concentration of 9-carboxymethoxymethylguanine (CMMG), the principal metabolite of acyclovir.
As such, the patient with weak kidneys (impaired renal function) continued risking the occurrence of delusional symptoms despite the reduction of the dose of acyclovir. Hemodialysis
resolved the patient's delusions (of negating the self) within hours of
treatment, which suggests that the occurrence of Cotard's delusion
symptoms might not always be cause for psychiatric hospitalization of
the patient.
Diagnosis
According to the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, 5th Edition), Cotard's delusion falls under the category of somatic delusions, those that involve bodily functions or sensations.
There are no further diagnostic criteria for Cotard's syndrome
within the DSM-5, and identification of the syndrome relies heavily on
clinical interpretation.
Cotard's delusion should not be confused with delusional disorders
as defined by the DSM-5, which involve a different spectrum of symptoms
that are less severe and have lesser detrimental effect on functioning.
Treatment
Pharmacological treatments, both mono-therapeutic and multi-therapeutic, using antidepressants, antipsychotics, and mood stabilizers have been successful. Likewise, with the depressed patient, electroconvulsive therapy (ECT) is more effective than pharmacotherapy.
Cotard's syndrome resulting from an adverse drug reaction to
valacyclovir is attributed to elevated serum concentration of one of
valacyclovir's metabolites, 9-carboxymethoxymethylguanine (CMMG).
Successful treatment warrants cessation of valacyclovir. Hemodialysis
was associated with timely clearance of CMMG and resolution of symptoms.
Case studies
- One patient, called WI for privacy reasons, was diagnosed with Cotard's delusion after experiencing significant traumatic brain damage. Damage to the cerebral hemisphere, frontal lobe, and the ventricular system was apparent to WI's doctors after examining magnetic resonance imaging (MRI) and computed tomography (CT) scans. In January 1990, WI was discharged to outpatient care.
- Although his family had made arrangements for him to travel abroad, he continued to experience significant persistent visual difficulties, which provoked a referral for ophthalmological assessment. Formal visual testing then led to the discovery of further damage. For several months after the initial trauma, WI continued to experience difficulty recognizing familiar faces, places, and objects. He was also convinced that he was dead and experienced feelings of derealization.
- Later in 1990, after being discharged from the hospital, WI was convinced that he had gone to Hell after dying of either AIDS or sepsis. When WI finally sought out neurological testing in May 1990, he was no longer fully convinced that he was dead, although he still suspected it. Further testing revealed that WI was able to distinguish between dead and alive individuals with the exception of himself. When WI was treated for depression, his delusions of his own death diminished in a month.
- In November 2016, the Daily Mirror newspaper carried a report of Warren McKinlay of Braintree in Essex, who developed Cotard's delusion following a serious motorbike accident.
