Cotards delusion, also known as walking corpse syndrome or Cotards 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 Cotards 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 (somatoparaphrenia) and of her need to eat. She claimed that she was condemned to eternal damnation, and therefore could not die a natural death. In the course of experiencing "the delirium of negation", Mademoiselle X died of starvation.Cotards delusion is not mentioned in either the Diagnostic and Statistical Manual of Mental Disorders (DSM) or the 10th 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 Cotards syndrome. The patient usually denies their own existence, the existence of a certain body part, or the existence of a portion of their body.
The problem with the hypothesis that has been proposed is that this condition does not reoccur and it does not progressively worsen. Currently there has been no evidence of detecting circulating antibodies that are associated with the onset on PUPPP in an individual. Diagnosis
PUPPP is often a diagnosis of exclusion and may need laboratory testing to rule out other dermatoses. Lab tests may include complete blood count, comprehensive metabolic panel, liver function tests, serum human choriogonadotropin and serum cortisol. Additional specialized tests may include serum for indirect immunofluorescence or biopsy of the lesions for direct immunofluorescence to rule out pemphigoid gestationis.A common misdiagnosis is urticarial pemphigoid gestationis, hence it is needed to exclude it while diagnosing PUPPP as clinical features can overlap. Therefore, histological and immunological studies are necessary to ensure there is no mis-diagnosis. During the case of pemphigoid gestationis, lesions usually occur during the earlier periods of gestation and often involve the umbilicus; as well as, having a positive immunofluorescence of perilesional skin. If there is eczema, people generally have a history of atopy, be it personal or through family. The eruption is identified by pruritic erythematous lesions on flexural areas. Furthermore, other clinical differential diagnosis could be from drug eruptions, urticaria, or viral exanthems.Sometimes, people may require a 3- or 4-mm punch biopsy to exclude herpes gestationis, which is a variant of bullous pemphigoid occurring during or immediately after pregnancy. Usually the biopsy has features that are consistent with PUPPP but there are no pathognomonic symptoms of the particular disorder.