OrganicPsychiatricDisorders

1. Organic Psychiatric Disorders

2. • Delirium.
• Dementia.
• Amnestic disorders
• Other organic psychiatric
syndromes.

3. What is organic psychiatric
disorders?
Psychiatric disorders resulting from
brain dysfunction caused by
organic pathology inside or
outside the brain.

4. Classification of organic mental
states
• Global syndromes…
Delirium.
Dementia.
• Specific syndromes…
Amnesic syndrome.
Organic mood disorder.
Organic delusional disorder.
Organic personality disorder.

5. Delirium
• Acute generalized impairment of brain
function.
• The most important features is
impairment of consciousness.
• The primary cause is often outside the
brain (eg …anoxia due to respiratory failure).

6. Delirium
• It is a common accompaniment of physical illness
occurring in…
 5-15 % of pts in general medical & surgical wards.
 20-30 % of pts in surgical intensive care units.
• It is especially common in the elderly.
• Most pts recover quickly & a few need specific
treatment.
• Terms such as confusional state & acute organic
syndrome are outdated .

7. Clinical Features
• Impaired consciousness
disorientation
poor concentration
• Behavior
overactive
underactive
• Thinking
ideas of reference
delusions
• Mood
anxious , irritable
depressed
perplexed
• Perception
misperceptions
illusions
hallucinations
• Memory
impaired
• Insight
impaired
• Fluctuating course ,worse in the
evening
• Amnesia (on recovery)

8. Aetiology
• Drug intoxication.
• Alcohol withdrawal.
• Metabolic failure..
Cardiac
Respiratory
Renal
Hepatic
Hypoglycaemia
• Fever..
systemic infection
• Neurological causes..
encephalitis.
space-occupying lesions.
raised intracranial pressure .
following an epileptic seizure.

9. Management
Obtain information from other informants
& medical notes
Assess the pt’s mental state
Confirm the diagnosis of delirium
Determine the physical cause & treat it
Reduce disorientation:
Reorientate repeatedly
Consistent routine
Reduce anxiety :
Reassurance
Medications
Avoid over- or understimulation
Inform & support relatives
If calm:
Moniter progress
If agitated ,disturbed ,or distressed:
Consider hypnotic at night
Monitor progress & review medications

10. Dementia
• Chronic generalized impairment of brain
function.
• Characterized by impairment of intellect
,memory & personality without impairment
of consciousness.
• The primary cause is within the brain .
• Most cases are irreversible (few can be treated)

11. Clinical Features
• Cognition..
poor memory
impaired attention
aphasia, agnosia, apraxia
disorientation
• Behavior..
odd & disorganized
restless & wandering
self-neglect
disinhibition
• Mood
anxiety
depression
• Thinking
slow ,impoverished
delusions
• Perception ..
illusions
hallucinations
• insight..
impaired

12. Aetiology
• Degenerative neurological disorders..
Alzheimer’s disease
Vascular dementia
lewy body dementia
Frontotemporal dementia
Huntington’s chorea
prion disease
parkinson’s disease
• Normal pressure hydrocephalus
• Intracranial tumor
• Other space –occupying lesions..
chronic subdural haematoma
• Traumatic ..
severe head injury
• Anoxia..
cardiac arrest
carbon monoxide poisoning
• Vitamin lack
vitamin B12
folic acid
thiamine
• Metabolic
DM
• Endocrine
hypothyroidism
• Infections..
postencephalitis ,HIV
• Vascular..
multi-infarct dementia
• Toxic
alcohol

13. Management
• Detailed history (informant).
• Mini mental state examination.
• Investigations…
CT…diagnosis of both focal & diffuse cerebral pathology.
 psychological testing….
 specific tests of memory ,learning & other aspects of cognitive
function…localized brain lesions.
.Medications
. Family support

14. Cont..
• Pseudodementia…
in this syndrome ,a depressed pt complains of poor memory &
appears intellectually impaired because poor concentration leads to
inadequate registration & deprssive mood leads to slowness & self –
neglect.
• Characteristic features….
a history from another informant that the depressed mood
preceded the memory problems .
 memory testing shows that the poor performance improves when
interest is aroused.
 the pt is retarded & unwilling to cooperate in the interview.

15. Cont..
• Delirium or Dementia??
Delirium Dementia
Acute onset Insidious onset
fluctuating course stable or progressive
impaired consciousness normal consciousness
Thinking disorganized thinking impoverished
Perceptual disturbance perceptual disturbance
common uncommon
Alertness usually normally alert
Impaired

16. Treatment
• Aims of treatment….
 maintain any remaining ability as
far as possible
 relieve distressing symptoms.
arrange for the practical requirements of
the pt.
 support the family