Psychosis Flashcards
What is psychosis
The presence of hallucinations or delusions Describes symptoms, not a diagnosis in itself
What are hallucinations
Perception without a stimulus
Can be in any sensory modality
Visual hallucinations are usually organic (caused by problem with brain or eyes)
What are delusions
Delusion – abnormal belief, outside of cultural norms, unshakeable
What is organic psychosis
Organic psychosis •Delirium caused by infection •Delirium tremens •Acute drug/alcohol intoxication •Post-ictal psychosis •Hyperthyroidism •Encephalitis (including anti-NMDA receptor) •Hypercalcaemia •Cerebral lupus(and many more!)
Don’t forget iatrogenic causes
•Steroids
•L-dopa
What are first rank symptoms
Schneiderian first-rank symptoms (FRS) of schizophrenia encompass a small range of hallucinations and delusions: • Auditory hallucinations • Passivity experiences • Thought withdrawal, broadcast or insertion • Delusional perceptions • Somatic hallucinations
What are examples of auditory hallucinations
Thought echo – hearing thoughts aloud
Running commentary –
‘He’s brushing his teeth, he’s sitting down’
Voices referring to patient in third person and conversing with each other about the patient
What are passivity experiences
Patient believes an action or feeling is caused by an external force, ‘MI5 have been moving my leg’
What is thought withdrawal, broadcast or insertion
Thought withdrawal – thoughts are being taken out of the mind
Thought broadcast - thoughts are being made known to others e.g. via radio
Thought insertion – thoughts implanted by others
What is delusional perception
Delusional perception
‘attribution of new meaning,
usually in the sense of self-reference, to a normally perceived object’
New meaning cannot be understood as arising from patient’s affective state or previous attitudes
‘The traffic lights went red and I knew this was a sign that aliens were going to land soon’
What are somatic hallucinations
Somatic hallucinations
Mimics feeling from inside the body
What are positive and negative symptoms of schizophrenia
Positive symptoms:
Delusions, hallucinations, thought disorder, lack of insight
ie Added symptoms
Negative symptoms:
Underactivity, low motivation, social withdrawal, emotional flattening,
Self neglect
Symptoms that take away from the patient
What are he icd10 criteria for scizophrenia
- At least one of the following
a) Thought echo, insertion, withdrawal, broadcast
b) Delusions of control, influence or passivity, clearly referred to body/limb movements or specific thoughts actions or sensations, delusional perception
c) Hallucinatory voices giving a running commentary on the patient’s behaviour, or discussing them between themselves, or other types of hallucinatory voices coming from some part of the body
d) Persistent delusions of other kinds that are culturally inappropriate and completely impossible
Or at least 2 of the following
e) Persistent hallucinations in any modality, when occurring every day for at least one month, when accompanied by delusions
f) Neologisms, breaks or interpolations in the train of thought, resulting in incoherent or irrelevant speech
g) Catatonic behaviour
h) Negative symptoms such as marked apathy, paucity of speech and blunting or incongruity of emotional responses
What are types of schizophrenia
Paranoid schizophrenia –
delusions or hallucinations prominen
Simple schizophrenia – loss of drive and interest, aimlessness, idleness, self absorbed attitude and social withdrawal. Marked decline in social, academic or work performance. No hallucinations/delusions
Hebephrenic schizophrenia – definite and sustained flattening or shallowness of affect or incongruity/inappropriateness of affect, aimless and disjointed behaviour or thought disorder affecting speech Hallucinations/delusions must not dominate
Undifferentiated schizophrenia – insufficient symptoms to meet criteria of any subtypes or so many symptoms fit more than one criteria
Catatonic schizophrenia
Describe the pathophysiology of schizophrenia
Dopamine pathways
Brain changes
Limbic system
Mesolimbic pathway is involved in reward, pleasure, motivation; thought ot be overactive in scizophrenia:
From Ventral tegmental area To Limbic structures (amygdala, septal area, hippocampal formation)
and Nucleus accumbens (large ceell group in basal forebrain)
Mesocortical pathway involved in cognition, motication, emotional response; thought to be underactive in scizophrenia
From Ventral tegmental area To Frontal cortex and Cingulate cortex
What is the ventral tegmental area
The ventral tegmental area (VTA) is a structure in the midbrain which sends dopaminergic neural projections to both the limbic and cortical areas
What are the brain changes in scizophrenia
Enlarged ventricles
Reduced hippocampal formation, amygdala, parahippocampal gyrus and prefrontal cortex
What are other theories for pathogeneis is of schizophrenia
Involvement of the limbic structures –
as they have a role in regulating emotional behaviour
Basal ganglia –
even untreated patients can present with motor symptoms
What is the autommune hypothesis for scizophrenia
Anti-NMDA encephalitis
In over 18s, around 50% have an underlying tumour (most commonly an ovarian teratoma)
•Antibodies bind to NMDA receptor, receptor internalised, leads to hypofunction
•Treated with corticosteroids and intravenous immunoglobulin
Trials of immunoglobuins now starting
Describe the drug treatment for scizophrenia
Typical antipsychotics
• Block D2 receptors in all CNS dopaminergic pathways
• Main action as antipsychotics is on mesolimbic and mesocortical
pathways
Atypical antipsychotics
• Low affinity for D2 receptors
• Milder side effects as dissociate rapidly from D2 receptor
What are comsprobems in the treatment f scizophrenia
Ss
Describe the basal ganglia
INPUT From cortical and subcortical areas PROCESSING striatum (caudate nucleus and putamen) Allows integration of information Basal ganglia encode for the decision to move, the direction and amplitude of movement and motor expression of emotions
OUTPUT
Inhibitory projections from
globus pallidus and substantia nigra to thalamus
Describe the effects on the nigrostratal pathway on antipsychotics
Nigrostriatal pathway
From
Substantia nigra pars compacta
To Striatum (caudate nucleus and putamen)
In summary, less dopamine = less movement
Why do untreated patients develop Catatonia if dopamine promtes movement?
More than two weeks, one or more of • Stupor / mutism • Excitement • Posturing • Negativism • Rigidity • Waxy flexibility • Command automatism
Probably due to less GABA binding so loss of inhibitory effect
What are good prognostic factors
Focus on early intervention and better treatments available mean prognosis is better
Moderately good long term global outcome in about 50%
Good prognostic factors Absence of family history Good premorbid function Acute onset Mood disturbance Prompt treatment Maintenance of initiative and motivation
-
Lorazepam
Desribe mortality ad morbidity of psychosis
Mortality is twice as high as in general population
Shorter life expectancy
Higher incidence of CVS disease, respiratory disease and cancer
Suicide risk is 9x higher than in general population
Death from violent incidents in 2x as high
About 50% have a substance misuse problem
Higher rate of cigarette smoking
What is drug induced psychosis
Psychosis induced by a psychoactive substance
Methamphetamine, cannabis, cocaine, amphetamines, LSD, ecstasy, ketamine (but can be pretty much anything!)
ICD 10 criteria
Onset of psychotic symptoms during or within two weeks of substance use
Persistence of the psychotic symptoms for more than 48 hours
Duration of the disorder not exceeding six months
What is affective psychosis
Psychotic experiences are normally congruent with mood
For example, manic patients may have grandiose delusions, hear the voice of God talking to them etc
Depressed patients may have delusions of guilt or nihilism, unpleasant auditory hallucinations
Decsribe postpartum psychosis
Affects 1 in 1000 women
Very severe and needs to be recognised quickly to avoid harm to mother or baby
Can present in patients with no previous psychiatric history More common if previous bipolar disorder or psychotic illness, or mother or sister suffered
Onset within days to weeks of delivery
Can develop over hours to days
