Psychiatry - Schizophrenia and psychosis Flashcards
(40 cards)
Symptoms of psychosis
1) Delusions
2) Hallucinations
3) Passivity phenomena
These tend to be episodic
Delusions
= false belief that is held unshakably despite evidence to the contrary. It is not culturally appropriate
Delusions are abnormal thoughts
Hallucinations
= perception which arises in the absence of any external stimulus
Auditory hallucinations are the most common
Passivity phenomena
= patient feels that he/she is being controlled externally. This may affect their thought processes (e.g. thought insertion, thought withdrawal, made feelings, made impulses etc)
Are all hallucinations pathological?
No.
Hallucinations can occur in special situations such as those associated with sleep (hypnagogic and hypnopompic). These are non pathological and it is usual for the patient to retain insight and recognise these are not true or real experiences. This is not the case in psychosis
What are the 4 non affective (mood related) or primary psychoses?
1) Schizophrenia
2) Schizoaffective disorder
3) Persistent delusional disorder
4) Acute and transient psychosis
Diagnosis may change over time - e.g. presentation with acute and transient psychosis may progress to symptoms of schizophrenia
What is thought insertion and withdrawal?
Caused by passivity phenomena
Thought insertion - thoughts originate elsewhere and are put into the patients head
Thought withdrawal - the experience of thoughts being removed from one’s mind
Characteristics of schizophrenia
Chronic illness characterised by repeated episodes of psychosis, particularly Schneider’s first rank symptoms
Patients may also experience negative symptoms that are not episodic - usually remain and worsen
What are Schneider’s first rank symptoms?
Symptoms of psychosis which if present are considered to be suggestive of schizophrenia (can occur in 8% of patients with bipolar)
1) Third person auditory hallucinations - discussing/ running commentary
2) Thought echo (hear own thoughts out loud)
3) Delusional perception (delusion arises from a real perception
4) Passivity phenomena
- Thought insertion/ withdrawal/ broadcast (thoughts interfered with)
- Passivity and somatic passivity
Negative symptoms of schizophrenia
Symptoms that develop gradually and progressively unlike the episodic symptoms of acute psychosis
- impaired motivation
- lack of drive
- social withdrawal
- reduced reactivity
- poverty of speech
- self neglect
Schizoaffective disorder
= Simultaneous presence of both typical symptoms of schizophrenia and affective disorder, neither being predominant
Persistent delusional disorder
= At least 3 months duration of one or more delusions
Other psychotic symptoms and negative symptoms of schizophrenia are absent
Acute and transient psychosis
= Sudden onset of rapidly changing symptoms of florid psychosis - strong mood element is common (that does not precede the psychosis)
Episode often precipitated by some stressful event. Usually lasts no longer than 3 months
Physical causes of psychosis
1) Any cause of delirium
2) Head injury/ intracranial pathology
3) Degenerating dementias
4) Epilepsy
5) Acute intermittent porphyria
6) Hyperthyroidism
What drugs can cause psychosis?
- L-DOPA
- Steroid hormones
- Disulfiram
- Anticonvulsants
Why does drug or alcohol abuse lead to psychotic symptoms?
2 reasons:
1) Intoxication with some drugs (e.g. amphetamines) can cause psychosis - psychosis usually resolves once the drug has been cleared
2) Drug misuse can precipitate psychosis in patients who have mental illness (e.g. schizophrenia) - psychosis may persist after patient has stopped drug abuse
Diagnostic work up in a patient to rule out organic cause of psychosis
- Physical examination
- FBC, U&E, LFTs, TFTs
- MRI of head should be considered in all first presentations of psychosis to rule out an underlying disorder (e.g. epilepsy, head trauma, encephalitis)
What drugs are associated with acute florid psychosis?
Amphetamines
Visual hallucinations suggest psychosis due to drug intoxication - urine sample may be required
What differentiates a manic episode from acute and transient psychosis?
Mania should be a differential for acute psychosis
Mania/ affective disorders with psychotic symptoms has a prolonged period of deteriorating mood prior to the onset of psychosis which is normally precipitated by stressful event
How long should anti-psychotic medication be maintained in a patient with acute psychosis?
Continuation antipsychotic treatment for at least 1 year to prevent relapse
What is the prognosis for a patient with an acute psychotic episode?
- Short term prognosis is good - psychosis will not usually last for more than 2/3 months
- Patients are more likely to experience further episodes
- Recurrence is less likely with maintenance antipsychotics
Typical presentation of low mood and symptoms of psychosis
- Psychosis can result from affective disorders (e.g. depression or bipolar)
- Normally, clear period of low mood PRECEDING the onset of psychosis
- Psychotic symptoms are normally mood congruent - i.e. in keeping with the affective disorder, so with depression negative/ insulting hallucinations, pessimistic ideas/ delusions, feelings of guilt
Prognosis in depressive episodes with psychosis
- Short term prognosis is good - response to treatment is usual
- Depression is relapsing so likely to have further episodes in the future
- Recurrence is reduced by maintenance antidepressant treatment
Diagnostic criteria for schizophrenia
First rank symptoms or persistent delusion + present for at least 1 month (ICD-10) + no drug intoxication, withdrawal, organic brain disease or prominent affective symptoms