Schizophrenia and Related Psychoses

Schizophrenia and Related Psychoses

Schizophrenia and Related Psychoses   

Schizophrenia:

Introduction:

Of all the psychiatric syndrome, schizophrenia is the most difficult to define and describe. Over the last 100 years widely divergent concepts have been held in different countries and by different psychiatrists.

Basic concepts are (over simplified)

Acute schizophrenia (Type 1):

Predominated by positive symptoms such as delusions, hallucinations and interference with thinking. Good prognosis

Chronic schizophrenia (Type II):

Negative symptoms: apathy, lack of drive (diminished volition), slowness and social withdrawal. Poor prognosis.

Recent studies proposed more complex delineations correlating to cerebral and psychological symptoms

Reality disturbance: delusions and hallucinations, left medial temporal lobe and cingulated cortex. Disorder of self monitoring. Disorganization: Formal thought disorder, inappropriate affect, bizarre behaviour, anterior cingulated, right ventral frontal cortex, bilateral parietal regions. Disorder of selective attention (suppression). Psychomotor poverty: Flat affect, poverty of speech, decreased spontaneous movement, under activity of pre-frontal cortex. Disorder of word generation and planning (initiation)

Other aspect of the clinical syndrome:

 Depressive symptoms: may be part of the syndrome, post psychotic phase or side-effect of the antipsychotic.

 

Cognitive features: impairment in learning, memory and attention.

 

Neurological signs: so cold soft signs. Abnormality in sensory integration, coordination, and catatonic features.

 

Olfactory dysfunction: affecting the identification, sensitivity and memory for odours usually worse in the left nostril. Clinically may contribute to lack of social drive.

 

Water intoxication: in few chronic patient water intoxication characterized by polyuria and hyponatraemia. May indicate hypothalamic regulation abnormality esp. related to antidiuretic hormone.

Diagnosis:

ICD-10:

At least one clear symptom (similar to Schneider’s first rank symptoms i.e. break down of self boundary)

a. Thought echo, insertion, withdrawal, broadcast

b. Delusions of control (passivity), delusional perception

c. Voices discussing in the third person, running commentary, voices from some part of the body.

d. Other persistent delusions that are completely impossible

Or at lease 2 symptoms:

a. Persistent hallucinations ± delusions (e.g. persecutory, reference, religious etc).

b. Formal thought disorders (flight of ideas, perseveration, loosening of association, widening of concept)

c. Catatonic behaviour e.g. posturing, stupor

d. Negative symptoms

e. Change in overall quality of personal behaviour

Illness for 1 month (DSM-IV 6 months).

Sub types:

Paranoid: stable delusions and usually hallucinations Hebephrenic: formal thought disorder, inappropriate affect, bizarre behaviour, fleeting delusions and hallucinations, severe illness. Catatonic: motor symptoms predominate Undifferentiated Residual: chronic stage, predominantly negative symptoms Simple: only negative symptoms Post-schizophrenic depression Other schizophrenia Unspecified schizophrenia

 (In DSM-IV: Paranoid, Disorganised, Catatonic, Undifferentiated, Residual)

Differences between the ICD-10 and DSM-IV):

ICD-10 places greater weight on first rank symptoms ICD 10 requires 1 month vs. 6 month in DSM-IV ICD 10 has more additional sub-types Disorganised in DSM-IV is called Hebephrenic in ICD-10.

Duration in DSM-IV:

1 day to 1 monthà Brief Psychotic Disorder

1 month to 6 monthsà Schizophreniform Disorder

More than 6 month à Schizophrenia

Differential Diagnoses

Organic syndromes “Organic Psychosis” ( as opposed to so called Functional psychosis such as schizophrenia)

e.g. TLE, carcinomas, CVA, AIDS, CJD, CO Poisoning, Fahr’s disease, Huntington’s, Syphilis, Wilson’s and many others.

(ALWAYS EXCLUDE ORGANICITY/MEDICAL CAUSES!!)

Drug induced psychosis Mood disorders with Psychotic Features Delusional Disorders Personality Disorders

Epidemiology of Schizophrenia

Lifetime risk 1%

Incidence: 0.5 per 1000

Prevalence: 3 per 1000

Median age of onset: M=28 yr, Females 32 yr (but anywhere between 15 to 55)

Gender M=F (early is more common in males, late (Paraphrenia) is more common in

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