Psychosis: differential diagnoses

Question 1

What other conditions can fall under the category of schizophrenia?

Answer 1

Persistent delusional disorder

Acute and transient psychosis

Schizotypical disorder

Question 2

What is a common feature of schizophrenia?

Answer 2

3rd person auditory hallucinations

A type of auditory hallucination in which a patient can hear voices talking about them usually in the 3rd person.

Example: “He/she(patient) is so annoying”.

Question 3

What are 2nd person auditory hallucinations?

Answer 3

A type of hallucination where a voice, or voices, talk directly to the patient.

The voice may be persecutory, critical, complimentary or issue commands to the patient. For example, the voice may say “You are going to die” or “kill him”.

Second person auditory hallucinations are often associated with psychotic disorders such as schizophrenia.

Question 4

How is psychosis diagnosis aided?

Answer 4

Aided by:

• Full and thorough psychiatric history
• Detailed mental state examination
• Associated psychiatric symptoms
• Natural history of the symptoms
• Exclusion of other possible causes

Question 5

What is delirium?

Answer 5

Acute, transient disturbance from person’s normal cognitive function.

Question 6

Characteristics of delirium?

Answer 6

Clouding of consciousness
- Ranges from subtle drowsiness to unresponsive
- Disorientation in time, place and person.

Impaired concentration/memory
- Especially for new information

Visual hallucinations/illusions +/- auditory hallucinations (often threatening).

Irritability

Insomnia

Question 7

ICD-10 criteria schizophrenia

Answer 7

At least one of the following:

A). Thought echo, thought insertion or withdrawal, or thought broadcasting.

B). Delusions of control, influence or passivity, clearly referred to body or limb movements or specific thoughts, actions, or sensations; delusional perception.

C). Hallucinatory voices giving a running commentary on the patient’s behaviour, or discussing him 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 (e.g. being able to control the weather, or being in communication with aliens from another world).

Question 8

ICD-10 criteria (2) schizophrenia?

Answer 8

or at least two of the following:

E). Persistent hallucinations in any modality, when occurring every day for at least one month, when accompanied by delusions (which may be fleeting or half-formed) without clear affective content, or when accompanied by persistent over-valued ideas.

F). Neologisms, breaks or interpolations in the train of thought, resulting in incoherence or irrelevant speech.

G). Catatonic behaviour, such as excitement, posturing or waxy flexibility,
negativism, mutism and stupor.

H). “Negative” symptoms such as marked apathy, paucity of speech, and blunting or incongruity of emotional responses (it must be clear that these are not due to depression or to neuroleptic medication).

Question 9

Positive symptoms of schizophrenia?

Answer 9

• Hallucinations
• Delusions
• Passivity phenomena
• Disorder of form of thought

Question 10

Negative symptoms of schizophrenia?

Answer 10

• Reduced amount of speech
• Reduced motivation/drive
• Reduced interest/pleasure
• Reduced social interaction
• Blunting of affect

Question 11

Negative symptoms of schizophrenia are easier to treat than positive symptoms. True/false?

Answer 11

False. Positive symptoms are easier to treat/manage.

Question 12

What is blunting of affect?

Answer 12

A decreased ability to express emotion through your facial expressions, tone of voice, and physical movements.

Question 13

What is passivity phenomena?

Answer 13

The belief that one’s thoughts or actions are influenced or controlled by an external agent

Question 14

Name 2 subtypes of schizophrenia.

Answer 14

Hebephrenic schizophrenia

Catatonic schizophrenia

Question 15

What is hebephrenic schizophrenia?

Answer 15

The symptoms of disorganised thoughts and behaviour are known as hebephrenia. Occurring mainly in 15-25 year olds

Hebephrenia is characterised by disorganised behaviour and speech as well as disturbance in emotional expression, known as mood incongruence.

Overall shallow and inappropriate mood, disorganised thought and incoherent speech.

Question 16

What is catatonic schizophrenia?

Answer 16

Catatonic schizophrenia patient will exhibit unusual styles and levels of physical movement.

For example, such a person may move their body erratically or not at all. This state may continue for minutes, hours, even days

Question 17

Examples of other paranoid psychoses?

Answer 17

Persistent delusional disorder

Schizotypical disorder

Acute and transient psychotic disorder

Induced delusional disorder

Schizoaffective disorder

Question 18

What is persistent delusional disorder?

Answer 18

Only major feature is when patient has systemised, fixed delusions.

Question 19

What is schizotypical disorder?

Answer 19

Disorder characterised by eccentric behaviour and anomalies of thinking and affect which resemble schizophrenia.

Symptoms may include a cold or inappropriate affect:
- Anhedonia (lack of joy/pleasure).
- Odd or eccentric behaviour
- Auditory and other hallucinations
- Delusion - like ideas
- Tendency to social withdrawal

Question 20

What is acute and transient psychotic disorder?

Answer 20

Schizophrenia-like symptoms lasting less than 1 month.

Question 21

What is induced delusional disorder?

Answer 21

Characterized by the sharing of delusional ideas and/or abnormal behavior from one person to one or more people who are in close association with the patient who is primarily affected.

Question 22

Schizoaffective disorder?

Answer 22

Episodic disorders in which both affective and schizophrenic symptoms are prominent but does not justify a diagnosis of either schizophrenia or depressive or manic episodes.