Certain infectious and parasitic diseases

due to organic mental disorder, and is too great to be explained by ordinary
forgetfulness or fatigue. The amnesia is usually centred on traumatic events, such
as accidents or unexpected bereavements, and is usually partial and selective.
Complete and generalized amnesia is rare, and is usually part of a fugue (F44.1).
If this is the case, the disorder should be classified as such. The diagnosis should
not be made in the presence of organic brain disorders, intoxication, or excessive
fatigue.
Excludes: alcohol- or other psychoactive substance-induced amnesic disorder (
F10-F19 with common fourth character .6)
amnesia:
· NOS ( R41.3 )
· anterograde ( R41.1 )
· retrograde ( R41.2 )
nonalcoholic organic amnesic syndrome ( F04 )
postictal amnesia in epilepsy ( G40.- )
F44.1 Dissociative fugue
Dissociative fugue has all the features of dissociative amnesia, plus purposeful
travel beyond the usual everyday range. Although there is amnesia for the period
of the fugue, the patient's behaviour during this time may appear completely
normal to independent observers.
Excludes: postictal fugue in epilepsy ( G40.- )
F44.2 Dissociative stupor
Dissociative stupor is diagnosed on the basis of a profound diminution or absence
of voluntary movement and normal responsiveness to external stimuli such as
light, noise, and touch, but examination and investigation reveal no evidence of a
physical cause. In addition, there is positive evidence of psychogenic causation in
the form of recent stressful events or problems.
Excludes: organic catatonic disorder ( F06.1 )
stupor:
· NOS ( R40.1 )
· catatonic ( F20.2 )
· depressive ( F31-F33 )
· manic ( F30.2 )
F44.3 Trance and possession disorders
Disorders in which there is a temporary loss of the sense of personal identity and
full awareness of the surroundings. Include here only trance states that are
involuntary or unwanted, occurring outside religious or culturally accepted
situations.
Excludes:
states associated with:
· acute and transient psychotic disorders ( F23.- )
· organic personality disorder ( F07.0 )
· postconcussional syndrome ( F07.2 )
· psychoactive substance intoxication ( F10-F19 with common
fourth character .0)
· schizophrenia ( F20.- )
F44.4 Dissociative motor disorders
In the commonest varieties there is loss of ability to move the whole or a part of a
196 WHO’s ICD-10