Organic Disorders Flashcards
What is the definition of organic disorder?
Organic disorder = mental disorder due to common, demonstrable aetiology in cerebral disease, brain injury, or other insult leading to cerebral dysfunction
Are organic disorders acquired or congenital?
They are acquired, so different from intellectual disability
Classification of organic disorders?
Primary
Secondary
- Primary
- Direct effect on the brain
- Secondary
- Systemic diseases that affect the brain in addition to other organ systems
Epidemiology - organic disorder
(age, onset)
- Onset
- Any age
- Adult or later life
Classification of organic disorder?
- Acute/subacute
- Delirium
- Organic mood disorder
- Organic psychotic disorder
- Chronic
- Dementia
- Amnesic syndrome
- Organic personality change
What are examples of organic disorders?
- Acute/subacute
- Delirium
- Organic mood disorder
- Organic psychotic disorder
- Chronic
- Dementia
- Amnesic syndrome
- Organic personality change
What are some common features of organic disorders?
- Cognitive
- Memory
- Intellect
- Learning
- Sensorium
- Consciousness
- Attention
- Mood
- Depression
- Elation
- Anxiety
- Psychotic
- Hallucinations
- Delusions
- Personality and behavioural disturbance
What can the following be broken down into:
- cognitive
- sensorium
- mood
- psychotic
- Cognitive
- Memory
- Intellect
- Learning
- Sensorium
- Consciousness
- Attention
- Mood
- Depression
- Elation
- Anxiety
- Psychotic
- Hallucinations
- Delusions
What is the general management for organic disorders?
- Correct diagnosis for correct management
- Medication usually not that useful except for acute situations
- MDT approach
- Management of environment
What is the prognosis for general disorders?
- Some irreversible and progressive
- Some transient/respond to treatment
Aetiology - delirium tremens
- Alcoholic withdrawal
Presentation - delirium tremens
- Fluctuating confusion
- Disorientation in time and place
- Memory impairment
- Psychotic phenomena
- Such as hallucinations, delusional thinking
Management - delirium tremens
- Benzodiazepines
What is Wernicke-Korsakoff syndrome also called?
Wernicke’s encephalopathy
Aetiology - Wernicke-Korsakoff syndrome
- Thiamine deficiency
Presentation - Wernicke-Korsakoff syndrome
- Acute confusional state
- Ataxia
- Opthalmoplegia
- Nystagmus
Treatment - Wenicke-Korsakoff syndrome
- High potency parenteral B1 replacement
- 3-7 days
- All patients with Wernicke’s encephalopathy or at high risk should get parenteral thiamine, others undergoing detoxification or under invest4igation should get oral thiamine
- Avoid carbohydrate load until thiamine replacement completed
- Concurrent treatment for alcohol withdrawal
Prognosis - Wernicke-Korsakoff syndrome
- Untreated acute phase lasts about 2 weeks
- 84% develop Korsakoff psychosis with 15% mortality
- With treatment
- Confusional state and opthalmoplegia can resolve within days
- Nystagmus, neuropathy and ataxia may be prolonged or permanent
What is alcohol amnesic syndrome also called?
Korsokoff’s psychosis
Clinical features - alcohol amnesic syndrome
- Characterised by marked impairment of anterograde memory (ability to learn new information), disturbance of time sense
- No clouding of consciousness, absence of defect in immediate recall or global impairment
- Variable degrees of cognitive impairment
- Personality changes
- Apathy
- Loss of initiative
- Confabulation in early stage
What is alcohol amnesic syndrome characterised by?
- Characterised by marked impairment of anterograde memory (ability to learn new information), disturbance of time sense
Prognosis - alcohol amnesic syndrome
- Can improve with prolonged abstinence
Aetiology - hepatic encephalopathy
- Normal seen in advanced alcohol liver disease
- Related to build up of toxic products like ammonia
Clinical features - hepatic encephalopathy
- General psychomotor retardation
- Drowsiness
- Fluctuating levels of confusion
Prognosis - hepatic encephalopthy
Pathology - alcohol related brain damage
- Part of a spectrum of alcohol related disorders, not specific diagnosis
Alcohol related brain damage - aetiology
- Can result from neurotoxic effects of alcohol
- Head injury
- Vitamin deficiencies
- Cerebrovascular disease
- Hypoxia
- Hypoglycaemia
- Seizures
Alcohol related brain damage - epidemiology
- 35% of alcohol dependent people exhibit post-mortem evidence of this
- Prevalence rising
Alcohol related brain damage - clinical features
- Cognitive impairment
- Impairment in short-term memory, long-term recall, new skill acquisition, set-shifting abilities
- Visuospatial ability declines greater than language ability decline
Alcohol related brain damage - investigations
- Imaging
- Cortical atrophy (mainly white matter loss) and ventricular enlargement
Alcohol related brain damage - prognosis
- Ability may recover spontaneously with abstinence/greatly reduced drinking
Dementia - pathology
- A syndrome characterised by global cognitive impairment which is chronic in nature
- Underlying pathology is variable and usually, but not always, progressive
Dementia - types
- Alzheimer’s
- Vascular
- Mixed
- Lewy body
- Frontotemporal
- Due to other brain disorders
- Huntington’s disease
- Head injury
- Parkinson’s disease
Compare the differences between dementia and pseudodementia for:
- onset
- long/short term symptoms
- mood
- answering of questions
- hiding/showing amnesia
- cognitive abilities
Steroid induced psychosis - epidemiology
- 1/3 of patients treated with steroids display mild-moderate psychotic symptoms
Steroid induced psychosis - management
- Taper steroids if possible
- Consider antipsychotic/mood stabiliser
Anti-NMDA receptor encephalitis - pathology
- Autoimmune disease that targets NMDA receptors
- Ionotropic glutamate receptor involved in synaptic plasticity and memory function
Anti-NMDA receptor encephalitis - aetiology
- ½ associated with malignancy
Anti-NMDA receptor encephalitis - clinical features
- Often presents with psychiatric symptoms
Anti-NMDA receptor encephalitis - investigations
- MRI
- Bilateral hippocampal hyper intensity
- EEG
- “Delta brush”
- Biochemistry
- Positive NMDAr antibodies in blood and CSF
What is seen in the following for anti-NMDA receptor encephalitis:
- MRI
- EEG
- biochemistry
- MRI
- Bilateral hippocampal hyper intensity
- EEG
- “Delta brush”
- Biochemistry
- Positive NMDAr antibodies in blood and CSF
Anti-NMDA receptor encephalitis - management
- Immunotherapy and tumour resection if indicated
- IVIg, plasmapheresis, rituximab
Anti-NMDA receptor encephalitis - prognosis
- With treatment is generally good
What is delirium characterised by?
An aetiologically non-specific syndrome characterised by:
- Concurrent disturbances of consciousness and attention, perception, thinking, memory, psychomotor behaviour, emotion and sleep-wake cycle
Delirium - aetiology
- Medication
- Drug abuse
- Withdrawal syndromes
- Metabolic
- Vitamin deficiencies
- Endocrinopathies
- Infections
- Neurological causes
- Toxins and industrial exposures
- (Basically anything)
Delirium - presentation
- Impairment of consciousness and attention
- Global disturbance of cognition
- Psychomotor disturbances
- Disturbance of sleep-wake cycle
- Emotional disturbance
- Rapid onset
- Diurnally fluctuating
- Physical signs
- Due to underlying disease
- Autonomic activation – tachycardia, hypertension, diaphoresis, dilated pupils, fever
- Dysgraphia
Describe the differences between delirium and dementia in terms of:
- onset
- course
- duration
- alertness
- orientation
- registration
- episodic memory
- thinking
- perception
- speech
- sleep/wake cycle
- other acute pathology
- EEG
- CT, MRI
What are the differences between delirium and psychosis for:
- conscious level
- thinking
- delusions
- cognitive functions
- hallucinations
Delirium - management
- Environmental and supportive measures
- Education of relatives
- Make environment safe
- Optimise stimulation
- Orientation
- Medication
- Avoid sedation unless required for safety
- Guidelines do not support use of medications in delirium
- Unless for acute management for safety – antipsychotics, benzodiazepines, promethazine
Delirium - prognosis
- Fluctuating course
- Gradually resolves after cause treated
- Slower symptom resolution in elderly
- Mortality
- 20% die during admission
- Up to 50% within 1 year
