Psychological Disorders: Shared Psychotic Disorder
American
Description
A delusion develops in an individual in the context of a close relationship
with another person(s), who has an already-established delusion.
The
delusion is similar in content to that of the person who already has
the established delusion.
The
disturbance is not better accounted for by another Psychotic Disorder
(e.g., Schizophrenia) or a Mood Disorder With Psychotic Features and
is not due to the direct physiological effects of a substance (e.g.,
a drug of abuse, a medication) or a general medical condition.
European
Description
A rare delusional disorder shared by two or occasionally more people
with close emotional links. Only one person suffers from a genuine
psychotic disorder; the delusions are induced in the other(s) and
usually disappear when the people are separated. The psychotic illness
of the dominant person is most commonly schizophrenic, but this is
not necessarily or invariably so. Both the original delusions in the
dominant person and the induced delusions are usually chronic and
either persecutory or grandiose in nature. Delusional beliefs are
transmitted this way only in uncommon circumstances. Almost invariably,
the people concerned have an unusually close relationship and are
isolated from others by language, culture, or geography. The individual
in whom the delusions are induced is usually dependent on or subservient
to the person with the genuine psychosis.
Diagnostic
Guidelines
A diagnosis of induced delusional disorder should be made only if:
(a)
two or more people share the same delusion or delusional system and
support one another in this belief;
(b) they have an unusually close relationship of the kind described
above;
(c) there is temporal or other contextual evidence that the delusion
was induced in the passive member(s) of the pair or group by contact
with the active member.
Induced
hallucinations are unusual but do not negate the diagnosis. However,
if there are reasons for believing that two people living together
have independent psychotic disorders neither should be coded here,
even if some of the delusions are shared.
Includes:
* folie a deux
* induced paranoid or psychotic disorder
* symbiotic psychosis
Excludes:
* folie simultanee