Organic Psychiatric Disorders

ENDOCRINE, METABOLIC AND DEFICIENCY DISORDERS
 
THYROTOXICOSIS
 
HYPOTHYROIDISM (Myxoedema)
 
VITAMIN DEFICIENCIES
 
 HEPATIC ENCEPHALOPATHY
 
CUSHING'S DISEASE
 
ADDISON'S DISEASE
 
RENAL ENCEPHALOPATHY


ACUTE ORGANIC BRAIN SYNDROMES

 
CHRONIC ORGANIC BRAIN SYNDROME
THE DEMENTIAS


THE AMNESIC SYNDROMES



 
 
 

A. ENDOCRINE, METABOLIC AND DEFICIENCY DISORDERS

THYROTOXICOSIS

 Psychological symptoms are almost invariably present.

 Common.

Anxiety, hyperactivity, emotional lability.

Often no preceding history of anxiety

May be no psychological precipitants.

 Less common.

Depression with agitation or apathy, early morning waking.

May persist after return to euthyroid state, and require antidepressant therapy.

Euphoria or 'hypomanic veneer'.
 
 

Rare.

Acute organic confusion (in severe toxicity),

schizophrenic reaction.
 
 

Physical

Weight loss in spite of good appetite,

intolerance of hot weather,

sleeping pulse more than 90/minute,

atrial fibrillation.

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HYPOTHYROIDISM (Myxoedema)

Basically an organic mental syndrome with secondary psychological features depending upon personality type. Most common in the elderly. When it occurs in infancy or childhood it may lead to mental handicap if it remains untreated; it is reversible if treated early.
 
 

Common.

Memory impairment, dulled comprehension.

May lead to irreversible dementia.

Depression with lethargy, irritability (may present in this way): can persist after return to euthyroid state and require antidepressant therapy.
 
 

Less common.

Coma: often precipitated by infection, high mortality when hypothermia also present. (< 35'C).

Excessive suspiciousness, paranoid and hallucinatory psychosis.

Mania.
 
 

Physical features.

Cold sensitivity,

physical slowness,

weight increase,

non-pitting oedema (pretibial),

facial puffiness,

hoarse voice,

coarse dry skin,

thinning of hair,

carpal tunnel syndrome,

angina (secondary to hypercholesterolaemia).

Richard Asher coined the term 'myxoedema madness' to include a wide variety of psychiatric states.

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VITAMIN DEFICIENCIES

VITAMIN B1 (thiamine) DEFICIENCY

See Wernicke's encephalopathy and Korsakoff's psychosis
 
 

VITAMIN B 12 DEFICIENCY
 
 

Distinctive.

Memory deficits, poor concentration: found in 25% of patients with Addisonian anaemia. May precede neurological and haematological abnormality.
 
 

Screen for B12 deficiency: all undiagnosed organic brain syndromes, especially in elderly, postgastrectomy, other intestinal diseases, severe chronic dietary deficiency.

May be progressive dementia in severe cases.
 
 

Non-specific.

Affective disorder (anxiety, irritability, depression) in 20%.

Folic acid deficiency is said to be more likely to cause affective disorder (56%).
 
 

NICOTINIC ACID DEFICIENCY (Pellagra)

Tryptophan deficient diets.

Neglect of diet in elderly.

Secondary to chronic diarrhoea.
 
 

Initial depression.

Later confusion, delirium and dementia.

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HEPATIC ENCEPHALOPATHY

 A range of neuro psychiatric disorders associated with hepatic insufficiency.
 
 

Clinical features

Chronic organic brain syndrome punctuated by episodic disorders of consciousness, with or without delirium and finally coma.
 
 

In early stages:

- exaggeration of personality traits

- anxiety depression or denial
- reversal of sleep rhythm
- slowing of EEG
- fluctuating degrees of concentration, awareness
- constructional apraxia
In later stages:
- confusion, inappropriate behaviour
- delusional ideas, hallucinations
- visual illusions (micropsia)
Causes
Due to metabolic changes secondary to liver cell failure. Precise metabolites involved uncertain:
- raised blood ammonia usually found but its level does not correlate closely with severity of symptoms
- toxic products of protein breakdown (such as methionine and tryptophan metabolites) entering systemic blood supply via new collateral extrahepatic and intrahepatic shunts
- short chain fatty acids may also be toxic
- accumulation of neurotransmitters, originating from bacterial protein breakdown in gut
- coma may be precipitated by diuretics, high protein intake, presence of blood in gut, intercurrent infection, sedatives, phenothiazines, monoamine inhibitors and other antidepressants. Portals systemic shunt (especially if surgically induced in treatment of portal hypertension) may be cause of delusional hallucinatory symptoms and central nervous damage (paraplegia, cerebellar and basal ganglion disease, epileptic fits).

 
 

Differential diagnosis

Important to distinguish alcoholic delirium tremens from hepatic encephalopathy if only because sedatives can be fatal in latter.
 
 

Liver failureDTs

Hypoactive apathetic state Physically overactive

May resemble depression Vivid visual hallucinations, severe anxiety

Irregular flapping tremor Tremor coarse, rhythmic

may occur
 
 

EEG: progressive slowing

with high amplitude

triphasic waves
 

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CUSHING'S DISEASE

 Due to excess production of cortisol with variable amount of adrenal androgens.

Adenoma or carcinoma of adrenal cortex (20%)

adrenal hyperplasia(80%).

Psychological symptoms in >50%: more likely

history o previous psychiatric difficulties, improve with adequate treatment of endocrine disorder.
 
 

Common. Depression with anxiety or retardation, excessive fatigue, stupor, episodic acute excitement, anxiety, impotence, amenorrhoea, loss of libido. Severity of depression not related to levels of circulating cortisol: it may be rapidly relieved when tumour or hyperplastic gland removed. Tumour less commonly associated with psychiatric symptoms than is hyperplasia.

Less common. Paranoid delusions,hallucinations. Elation,

Acute organic reactions: may be subjective complaint o memory Impairment when objective findings minimal.


ADDISON'S DISEASE

 Chronic adrenocortical insufficiency of cortisol, aldosterone, corticosterone and androgens. Primary atrophy (up to 50%). In the past tuberculosis more common. Psychological symptoms present in all severe cases. Mild memory impairment (75%). Organic type symptoms vary with severity of underlying endocrine deficiency and hypoglycaemia: in crisis there may be delirium. Depression (25%), apathy (25%), irritability (up to 50%). Rare to see other psychotic symptoms.
 
 

ACTH AND CORTICOSTEROID THERAPY

 Psychological symptoms more likely with high doses or prolonged treatment, or history of previous psychiatric diffleulties. Euphoria (up to 70%). Depression far less common (contrast Cushing's Disease). Irritability, tension. PS chosis (5%): mania, depression, stupor, disorientation, delusions, hallucinations, catatonia. Psychological dependence with depression as a result of steroid withdrawal, sometimes occurs.
 
 

HYPOPITUITARISM

 Chronic anterior pituitary failure. Most commonly due to postpartum ischaemic necrosis. Early loss of libido, pubic and axillary hair. Skin pale, wrinkled. Weight loss not a significant feature. Depression, apathy, self neglect. Sensitivity to cold. Sleepy. Memory impairment. Episodes of confusion. delirium, liability to become comatose and die in absence of endocrine replacement.
 
 

 PHAEOCHROMOCYTOMA

 May lead to episodic symptoms which mimic acute anxiety. Usually severe headache. Often precipitated bv emotional arousal or physical exertion.
 
 

INSULINOMA

Episodic which may be out of character. aggression, confusion and loss of consciousness in severe cases.
 
 

FURTHER READING

Lishman,W.A. (1978) Organic Psychiatry. Oxford: Blackwell.

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RENAL ENCEPHALOPATHY

Clinical features May be due to

- uraemia

- underlying disease process
- secondary physical and psychological complications
Uraemic encephalopathy
Essentially an organic brain syndrome. Psychological disturbance found in 75% of patients who have blood urea of more than 250 mg%. At first: fatigue, headache, poor concentration. Later: episodic confusion or delirium, coma.

 
 

Neurological disorder

Myoclonic jerks, asterixis, (metabolic flap) usually at times of clouded consciousness, extra pyramidal rigidity, involuntary movements, neuropathy (painful paraesthesiae, restless legs syndrome), polymyositis (proximal limb weakness, epileptic fits (33%), reversible amaurosis.
 
 

EEG changes

Degree of abnormality correlated with level of consciousness. Generalised slow wave activity, disorganisation, episodic semi-rhythmic slow waves, may be triphasiforms, abnormal arousal responses. Spontaneous paroxysmal epileptiforabnormalities also induced by photic stimulation, with or without convulsions. Poor correlation with blood urea levels; other metabolic changes interact.
 
 

Dialysis: marked EEG changes during or after, especially if dialysis disequilibrium syndrome, features as above in uraemia. Chronic dementia analysis: diffuse slow waves, superimpose rythmic high amplitude slow waves, triphasic waves, complex discharges. May precede clinical change, and made transiently worse by dialysis.
 
 

Psychological disturbance

Depression: early features of uraemia may mimic this, but may develop secondarily.

Anxiety

Secondary defence mechanisms
 
 

Aetiology

 Neuropathological. Some neuronal degeneration and loss. May be overshadowed by vascular complications due to secondary disorders such as hypertension. Urea itself not neurotoxic.
 
 

Electrolyte and acid/base changes. Especially when these are rapid.
 
 

Water intoxication
 
 

Abnormal neurotransmitter metabolism
 
 

Wernicke's encephalopathy: thiamine deficiency.
 
 

Iatrogenic. High doses of penicillin may cause fits. Diuretics may cause hypokalaemia. Immunosuppressants and steroids may predispose to viral or fungal meningoencephalitis or reticuloendothelial tumours.
 
 

Effects of dialysis

When carried out rapidly or there is severe initial metabolic abnormality, then dialysis may lead to a 'disequilibrium syndrome' of headache, confusion, fits, coma. This may be due to cerebral oedema, or reactive hypoglycaemia may also be a factor.

Dementia may also complicate dialysis. Usually progressive and fatal in few months, often with osteomalacia, multiple bone fractures, orofacial grimacing and fits. Appears to be unrelated to biochemical disturbance, and not improved by further dialysis. May be due to accumulation in brain of aluminium derived from water used in dialysis.
 
 

Hospital ward regimes

May involve social isolation and sensorv deprivation. These may heighten anxiety, accentuate confusion, precipitate delirium or paranoid reaction.
 
 

Renal transplantation donors

Careful psychological screening of potential donors.

Sudden irrational decision suspect especially when family coercion present.

 Exclude donor who has markedly ambivalent relationship with recipient

ORRANIC BRAIN SYNDROMES

CHARACTERISTIC CLINICAL FEATURES
Tend to show marked fluctuation in severity, worse at night.
1. Memory loss (most severe for recent events)
2. Impairment of consciousness (especially in acute forms).
3. Disorientation (time, place, person).
4. Intellectual impairment (defect of grasp, reasoning, social disinhibition).
5. Non-specific: hallucinations (especiaIly visual), mood disturbances (lability, depression), delusional ideas, focal neurological signs.
 
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ACUTE ORGANIC BRAIN SYNDROMES
 Disorientation and clouding of consciousness predominate. May also be anxiety, bewilderment, illusions, hallucinations (delirium).

 
 

Causes

Metabolic, infective, toxic, traumatic, degenerative, vascular. Alcohol or barbiturate withdrawal in habituated individuals, nutritional deficiency. Wernicke's encephalopathy (thiamine deficiency), begins with global confusional state, drowsiness, inattention, disorientation, failure of identification. Nystagmus and ocular palsies frequent, and delirium tremens in a third. Emergency

need for treatment with intramuscular thiamine 50 mg daily. Rapid recovery possible, but may only be partial.

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CHRONIC  ORGANIC BRAIN  SYNDROME

THE  DEMENTIAS

Dementia is a syndrome arising from cerebral disease, primarily causing impaired recent memory, with additional variable disturbance of intellect, abstract thinking, judgement, personality, affect and higher cortical functions (e.g. orientation, speech). It occurs in the absence of any alteration in consciousness, but may cause episodic confusion or delirium. The loss of intellectual abilities interferes with social or occupational functioning. Progressive selective deficits imply focal dysfunction. 3-5% of people over 65 years have severe dementia, similar proportion milder effect. 80% over 80 years are not demented.
 
 

History

Essential to have objective information from relatives, friends and work cal leagues to ascertain change from premorbid function, duration, speed of onset and evidence of selective difficulty. Family history in case of inherited disorders, e.g. Huntington's Chorea.
 
 

Examination

To assess degree of deficit as well as possible causes.

a) Full general physical for evidence of systemic disease, e.g. metabolic or neoplastic.

b) Neurological for focal cranial nerve or limb signs. N.B. Look for apraxia - a defect of action inexplicable by simple motor or sensory loss - implies parietal lobe involvement.

c) Simple tests of mental function:

1. Language:

i) naming objects:
- nominal dysphasia if single nouns.
- expressive dysphasia if more extensive disability.
ii) spoken commands:
- receptive dysphasia -failure to understand single words or sentences.
- dyslexia - reading disability. If comprehension and speech intact, indicates dominant hemisphere parietooccipital lesion.
 
2. Calculation - 7s subtracted serially from 100 (is also a test of concentration).
- dyscalculia.
3. Spatial organisation - drawing a star or a cube.
4. Short term memory - digit span, usually more than 5 forward.
5. Problem solving - e.g. placing digits in reverse order.
6. Recent memory- recalling current events. Babcock sentence or 3 unrelated words and a simple address.
d) Where doubt remains and'or suspicion of selective deficits, then detailed psychometric assessment may be required.
 
Causes, presentation
Cerebral atrophy (50%). Senile dementia; Alzheimer senile (50-70% of patients over 65) and pre-senile types. Early memory loss, dressing apraxia, disorientation, fits, extrapyramidal signs. Neuronal loss, argentophil plaques, neurofibrillary cell changes. Marked involvement of parietal lobes. Pick's disease (rare). Mendelian dominant. Early social disinhibition (frontal lobe involvement). Rigid egocentric attitude. Focal neurological deficits common, e.g. dysphasia. Memory loss late. Neuronal loss, presence of balloon-like Pick cells.

 
 

Cerebrovascular disease Multi-infarct dementia (10-30%). Affects thalamus, basal ganglia, brainstem and cerebrum. Can be coincidental with dementia from other causes. Depression often marked initially.
 
 

Alcoholic dementia (5-10%). Cortical atrophy in excess of age effect. 5-10%). Cortical atrophy in excess of age effect.
 
 

Normal pressure hydrocephalus (Adams syndrome) (6%). Psychomotor retardation, ataxia and urinary incontinence. Insidious onset, ventricular enlargement, normal CSF pressure. May occur after head injury, subarachnoid haemorrhage, intracranial surgery, cerebrovascular disease, meningo~ncephalifis, with brainstem, glioma, third ventricular cyst, cerebellar tumour, aqueduct stenosis.

In half there is no obvious cause.

 Important because improvement can follow introduction of intracerebral shunt. Selection and investigation of patients needs care as significant morbidity associated with treatment.
 
 

Huntington's chorea (3%). Dominant autosomal inheritance. Incidence 5/100 000. Some sporadic cases occur (mutation). Onset 30-50 years of age. May be depression or paranoid state initially. Increased family incidence of suicide, antisocial behaviour. All children of an affected parent have 50% chance of developing the disease.
 
 

Parkinson's disease. This together with normal pressure hydrocephalus and Huntington's chorea sometimes called

'subcortical dementias' (see below).
 
 

Chronic drug intoxication
 
 

Miscellaneous diseases (7-10%).

- Traumatic. Degree of dementia correlates well with duration of post-traumatic amnesia (duration after injury before continuous memory recall is established).

- Punch-drunk syndrome. Cerebral atrophy, which progresses until retirement from the ring, only occasionally afterwards. Cerebellar, pyramidal, extrapyramidal signs, morbid jealousy, impotence.

- Metabolic. Hypothyroidism, when chronic and severe. Hypoglycaemia (intermittent disordered behaviour, confusion or loss of consciousness more common tha true dementia). Chronic renal dialysis, related to accumulation of aluminiumfrom dialysis fluid. Hyperadrenalism, Cushing's syndrome. Hepatic failure. Addisonian anaemia.

- Infective. Neurosyphilis: (general paralysis of the insane; G.P.l; tabo-paresis). May present with depression, grandiose paranoid psychosis (10%), social disinhibition. Human autoimmune deficiency syndrome (AIDS).

- Hypoxic. CoaI.gas poisoning: beware late deterioration after 10 days.

- Other neurological disorders. There may be inappropriate euphoria in multiple sclerosis; frontal lobe tumours can cause disinhibited behaviour. Dementia with Parkinson's disease, with cerebellar atrophy e.g. Ramsay-Hunt syndrome, neurosyphilis, Creutrfeldt-Jakob disease, chronic undetected subdural haematoma.

 
Subcortlcal Dementias
 Impaired cerebral function can arise from subcortical lesions in several sites, but the clinical presentation: tend to be similar -personality change, impaired memory. particularly retrieval, impaired information processing and ability to manipulate acquIred knowledge. May appear depressed, but in reality lack initiative, are slow but antidepressant: cause further oognitive difficulty. The functions of language, calculation, and learning remain intact-unlike the cortical dementia:.
Pathology affects subeortical grey or white matter or both. Causes include some frontal lobe tumours, the deterioration associated with progressive supra-nuclear palsy, Huntington's chorea, Parkinson's disease and other extra-pyramidal syndromes such as Wilson's disease, the spino~cerebellar degeneration:, and idiopathic calcification of the basal ganglia.
The differentiation of these syndromes from the cortical dementia: is not always easy. Coincidental development of Alzheimer's disease has been suggested as the explanation for the dementia in Parkinson's disease.
So far, no clear therapeutic advances have arisen from the subdivision.

 
 

Investigations

Hb, WBC, ESR (or plasma viscosity), W. R., and HIV antibodies in young at risk groups.

 EEG

Can be useful. but normal age changes, e.g. in dominant occipital frequency, may be confusing. Must exclude transient changes due to drug effects, toxic or metabolic disturbances. EEG slowing most common in Alzheimer senile type, positively correlated with cognitive impairment. In early stage may still be normal. Less value in multi-infarct type, unless infarcts large or near surface, when local or focal EEG abnormalities. Creutzfeldt.Jakob disease: slow, disorganised record with periodic complex discharges. May be abnormal sleep patterns in manifest senile dementia.

Results are of greater diagnostic value in patient groups than in individual.
 
 

Evoked potentials.

Differential abnormality of the flash compared with pattern visual evoked potentials reported in Alzheimer's disease. Somatosensory evoked potentials more likely to be abnormal in Aliheimer's disease and multi-infarct dementia. As with EEGs, results of greater diagnostic value in patient groups than in the individual.
 
 

CTscan

Evidence of atrophy, local or generalised. Degree of ventricular dilatation correlates with severity of dementia.

Combined CT scan and EEG with discriminant analysis can be valuable in Alzheimer's disease.
 
 

If necessary to investigate suspected neurological conditions: arteriography, isotope encephalography or in specialised centres MRI scan.
 
 

Differential diagnosis of dementia

Depression: may present with complaint of poor concentration and memory, (pseudo dementia). Schizophrenia: simulates dementia through autistic behaviour, self-neglect. hysterical amnesia: global or selective for traumatic events. Chronic drug intoxication: slow, poor concentration (may occur in epileptic patients).

In as many as 31% of patients presumed to be suffering from senile dementia the diagnosis is incorrect, being in fact a depressive illness or an acute confusional state (Ron 1979).
 
 

Drug treatment

'Cerebral metabolic enhancers', centrally acting vasodilators, drugs acting at various sites in the cholinergic systern, and a miscellaneous group including opioid and adrenergic antagonists, as well as anticonvulsants are all currently suggested as treatment regimens in dementia but have not been shown to have sufficiently sustained benefits to justify their general use outside a research setting.
 

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THE AMNESIC SYNDROMES

Recent memory defect (can register memory but only minimal recall present). May confabulate, confuse temporal sequence of events.
 
 

Sudden onset, usually with gradual but incomplete recovery' Bilateral hippocampal infarction (occlusion both posterior cerebral arteries), trauma affecting bilateral medial temporal lobes, subarachnoid haemorrhage, carbon monoxide poisoning. Traumatic, following a head injury (see separate section, p.33-35).
 
 

Sudden onset, short duration

Complex partial (temporal lobe) seizures. Post~oncussion. 'Transient global amnesia'1 common in the elderly, lasts a few hours: apparently normal behaviour but slight confusion of vascular origin (probable transient ischaemia of hippocampal region due to platelet emboli). Transient during any severe infection, e.g. severe pneumonia. Local infections: encephalitis, severe meningitis. Metabolic changes, e.g. cerebral hypoxia, deficiency diseases, steroids, toxic substances such as carbon monoxide, glue-sniffing, metallic poisons and drugs, acute alcohol poisoning.
 
 

 Subacute onset, varying degrees of recovery Wernicke - Korsakoff syndrome, herpes simplex encephalitis, tuberculous or other granulomatous basal exudates.
 
 

Slowly progressive

Tumours involving floor and walls of third ventricle, early stage of

Alzheimer's disease, other degenerative disorders with

disproportionate involvement of the temporal lobes.
 
 

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