Schizophrenia Spectrum Disorders

For further information, see CMDT Part 25-11: Schizophrenia Spectrum Disorders

Key Features

Essentials of Diagnosis

• Social withdrawal, usually slowly progressive, with decrease in emotional expression and/or motivation

• Deterioration in personal care with disorganized behaviors and/or decreased reactivity to the environment

• Disorganized thinking, often inferred from speech that switches topics oddly or is incoherent

• Auditory hallucinations, often of a derogatory nature

• Delusions, fixed false beliefs despite conflicting evidence, frequently of a persecutory nature

General Considerations

• Schizophrenia is manifested by a massive disruption of thinking, mood, and overall behavior as well as poor filtering of stimuli

• Cause is believed to be multifactorial, with genetic, environmental, and neurotransmitter pathophysiologic components

• The characterization and nomenclature of the disorders are quite arbitrary and are influenced by sociocultural factors and schools of psychiatric thought

• There may or may not be a history of a major disruption in the individual's life (failure, loss, physical illness) before gross psychotic deterioration is evident

• Other psychotic disorders on this spectrum are conditions that are similar to schizophrenia in their acute symptoms but have a less pervasive influence over the long term

Clinical Findings

Symptoms and Signs

• A history of a major disruption in the individual's life may precede gross psychotic deterioration

• Gradual decompensation usually predates the acute episode

• Positive symptoms

  • Delusions are often paranoid, involving perceived threat from others

  • Hallucinations are typically auditory

  • Hypersensitivity to environmental stimuli, with feelings of enhanced sensory awareness

• Negative symptoms

  • Diminished sociability

  • Restricted affect

  • Impoverished speech

• Appearance: may be bizarre, often with deterioration in personal care, though usually patients are just mildly unkempt

• Motor activity: generally reduced, although a broad spectrum is seen

• Social function: marked withdrawal, disturbed interpersonal relationships

• Speech

  • Neologisms (made-up words or phrases)

  • Echolalia (repetition of others' words)

  • Verbigeration (repetition of senseless words or phrases)

• Affect: flat, occasionally inappropriate

• Mood: depression in most patients, less apparent during acute psychosis, may have rapidly alternating mood shifts irrespective of circumstances

• Thought content

  • Varies from paucity of ideas to rich delusions

  • Concrete thinking with inability to abstract

  • Inappropriate symbolism

Differential Diagnosis

• Schizophrenia should be distinguished from other psychoses

  • Delusional disorders are characterized by persistent delusions with minimal impairment on daily life

  • Schizoaffective disorders fail to fit within the definitions of either schizophrenia or affective disorders

  • Schizophreniform disorders have a duration of less than 6 months, but more than 1 month

  • Brief psychotic disorders result from psychological stress, last less than 1 month, and have a much better prognosis

  • “Other psychotic disorders”

    • Patient usually attains higher levels of functioning than in schizophrenia

    • Acute psychotic episodes tend to be less disruptive of the person's lifestyle, with a fairly quick return to previous levels of functioning

  • Clues are precipitous onset and a good premorbid history

• Manic episodes

• Obsessive-compulsive ...