Somatisation and conversion disorders

Question 1

What are dissociative (conversion) disorders?

Answer 1

Loss of motor or sensory function normally under voluntary control - psychological cause

70-90% resolve at follow up

Question 2

How does the distribution of dissociative disorders give a clue that this is psychological in origin?

Answer 2

It does not follow of dermatomal distribution (follows what a lay person would imagine a physical illness to be)

Question 3

How do the DSM-IV and ICD-10 differ interior interpretation of dissociative/conversion disorders?

Answer 3

ICD-10 -both are synonymous

DSM-IV:
Conversion = motor and sensory deficit
Dissociation = disturbance in the function of consciousness (separating off memories from consciousness - amnesia, stupor, fugue)

Question 4

Clinical presentation of dissociative/conversion disorders?

Answer 4

Conversion:
Paralysis (stroke mimic) - flaccid (common and severe ) or contractures - 1 or more limbs, one side of face/body)

Sensory change (conversion) - doesn’t follow dermatomal pattern

Dissociation:
Aphonia (loss of speech) - complete or partial (whispers) - doesn’t effect writing or comprehension

Amnesia (memory loss) - often for recent events, patchy and selective - may have Hx of traumatic event

Fugue - dissociative amnesia - Hx of conscience travel outside of body

Question 5

Investigations into conversion/dissociative disorders?

Answer 5

Medical examination - exclude physical or neurological causes
Find positive sign - e.g. sensory loss that does not follow dermatome
Find psychological explanation - recent stress, grief, sexual abuse, FHx