Overview

• Psychosis → the experience of losing touch with reality through abnormal perceptions, beliefs and loss of functioning.
  • A perception in the absence of a stimuli = hallucinations.
    • (Illusion → distorted perception/misperception of a stimulus).
  • Fixed, false, unshakeable beliefe that is outside of cultural norms = delusions.
  • Abnormal functioning = lack of insight.
• 4 Dopamine Pathways:
  • Mesolimbic Pathway → positive symptoms (Antipsychotics act on mesolimbic pathway to improve symptoms)
  • Mesocortical → negative symptoms (Antipsychotics act on mesocortical pathway when causing side-effects)
  • Nigrostriatal → blockage of this pathway = EPSE side effects
  • Tuberoinfundibular → hyperprolactinaemia (blockage of this pathway cause symptoms related to excess prolactin)
• Differential Diagnoses:
  • Organic → dementia, delirium, epilepsy, parkinson’s, huntington’s, steroid-induced psychosiss, substance misuse.
  • Psychotic Disorders → schizopherenia, acute psychosis (resolves within 3 months), delusional disorder.
  • Affective disorders with psychosis → depression with psychotic symptoms, BPAD/mania with psychotic symptoms.
  • Post-partum/puerperal psychosis.
• Risk Factors → family history (strongest risk factor), black-caribbean ethnicity, migration, urban environment, cannabis use.
  • Risk of developing schizophrenia
    • monozygotic twin has schizophrenia = 50%
    • parent has schizophrenia = 10-15%
    • sibling has schizophrenia = 10%
    • no relatives with schizophrenia = 1%
• Brief Psychotic Disorder → lasts <1 month and subsequent return to baseline functioning.
• Schizophrenia ⇒
  • Psychosis (hallucinations, delusions, lack of insight) → ≥1 positive symptoms for >1 month and generally lasting >6 months.
  • Subtypes
    • Paranoid (most common) → main symptoms are prominent delusions and hallucinations.
    • Catatonic (psychomotor disturbance) → stupor (being immobile, mute and unresponsive), excitement, posturing (maintaining weird positions), rigidity, waxy flexibility.
    • Hebephrenic → usually 15-25 years old. Disorganised speech (neoligisms, knight’s move thinking) and mood. Inappropriate effect (eg. lauging at something sad).
    • Simple → NEGATIVE symptoms only.
  • Impacts functioning. Not caused by organic disease, substance misuse or underlying psychopathology.
  • Poor Prognostic Indicators → strong family history, gradual onset, low IQ, prodromal phase of social withdrawal, lack of obvious precipitant.
  • Life expectancy reduced by 20 years in comparison with general population.
  • Schizoaffective Disorder → presence of symptoms of schizophrenia (eg. delusions, heallucinations) for at least 1 month alongside features of a mood disorder (ie. mania or depression) [present together during one episode, or within two weeks of each other]. Mood disturbances must be present for majority of the period of illness, however, there should be a period of at least 2 weeks where psychosis is observed in the absence of mood symptoms (to distiguish from psychotic depression or mania with psychosis). Treated with an antipsychotic (eg. risperidone) with a mood stabiliser (eg. lithium).

Making Diagnosis

Clinical Features

• Schizophrenia ⇒
  • Positive Symptoms → delusions (fixed, false beliefs not in context with their situation) and hallucinations (perception in the absence of a stimulus to cause the perception).
    • Delusions → typically either persecutory or grandiose.
    • Auditory (most common) and visual hallucinations.
  • Negative Symptoms → reduced mood, blunted effect, social withdrawal, catatonic behaviour, alogia (paucity/poverty of speech), avolition (poor motivation).
  • Thought disorders → thought insertion (believe some of their thoughts are not their own but have been implanted by someone else), thought withdrawal (believe someone else is accessing their thoughts), thought broadcasting (believe everyone can hear their thoughts).
    • Circumstantiality → inability to answer a question without giving excessive uneccessary detail (but person does eventually return to original point).
    • Tangentiality → wandering from a topic without returning to it, usually with loosely discernible links.
    • Neologisms → new word formations (may combine two words). Sign of mania.
    • Clang Associations → ideas are related only by the fact they sound similar or rhyme.
    • Word Salad → completely incoherent speech where real words are strung together into nonsense sentences.
    • Knight’s Move → unexpected and illogical leaps from one idea to another. More commonly associated with schizophrenia.
    • Flight of Ideas → leaps from one topic to another but with discernible links between them. Speech at a fast rate. More commonly associated with mania.
    • Perseveration → repetition of ideas or words despite an attempt to change the topic.
    • Echolalia → repetition of someone else’s speech, including the question that was asked.
  • First-Rank Symptoms → those identified as being specifically indicative of the disorder. Include thought disorders (insertion, withdrawal, broadcasting), passivity phenomena (being controlled by external influence), delusional perceptions and auditory hallucinations (thought echo, third person voices, narration).
    • Visual hallucinations are not a first-rank symptom as they are common in other conditions.
    • Somatic Passivity → sensations being imposed on them.
    • Auditory Hallucinations
      • Thought Echo → patient’s thoughts appear to be projected out loud
      • 3rd Person Voices → people talking about you in 3rd person
      • Running Commentary → hear a running commentary out loud
      • Command → voices in 2nd person telling patient to do something
  • Catatonia → most commonly associated with schizophrenia (depression less common).

Investigations

• Rule out Organic Causes → MRI/CT (esp. in elderly person with new sudden onset psychosis).
  • FBC, U&Es, LFTs, urine drug screen, B12, folate and thyroid function tests.
• MRI: Hypoactivity in prefrontal cortex.

Management Plan

Schizophrenia

• If urgent emergency/risk to self/others → hospital admission.
  • Urgent Emergency → crisis resolution team and home treatment team.
  • Non-Urgent Emergency → Early Intervention in Psychosis (EIP) Team (FOR FIRST EPISODE PSYCHOSIS).