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Schizophrenia
It is a disorder characterized
by apathy, avolition, and affective blunting. These patients have alterations in thoughts,
perceptions, mood, and behavior. Many schizophrenics display delusions, hallucinations and
misinterpretations of reality.
DSM-IV Diagnostic
Criteria
Two or more of the following
symptoms present for one month
Delusions
Hallucinations
Disorganized speech
Grossly disorganized or catatonic behavior sscizophrenia
Negative symptoms, i.e.,
affective flattening, alogia, avolition
Decline in social and/or occupational functioning since the onset.
Continuous signs of illness for psychosis, psychotic at least six months.
Schizoaffective disorder and mood disorder with psychotic features.
The disturbance is not due to
substance abuse or medical condition.
If history of autistic disorder or pervasive developmental disorder is present,
schizophrenia.
Clinical
Features
No sign or symptom is
pathognomonic.
Prior history of schizotypal or
schizoid personality traits or disorder are often present.
Depressive symptoms may be
present, but duration of these symptoms has been brief compared to duration of the
psychotic symptoms.
Many symptoms are categorized
as either positive or negative.
- Positive Symptoms:
- Hallucinations are most
commonly auditory or visual, but can occur in any sensory modality.
- Delusions
- Disorganized behavior
- Thought disorder characterized
by loose associations, tangentiality, incoherent thoughts, neologisms, thought blocking,
thought insertion, thought broadcasting, and ideas of reference.
- Negative Symptoms:
- Poverty of speech or poverty of
thought content
- Anhedonia
- Flat affect
- Loss of motivation (avolition)
- Attentional deficits
The presence of tactile,
olfactory or gustatory hallucinations may indicate an organic etiology such as complex
partial seizures.
Sensorium and memory are intact
unless the patient is too psychotic to engage in testing.
Insight and judgment frequently
impaired.
Epidemiology
- Lifetime prevalence of is one
percent.
- Onset of psychosis usually
occurs in late teens or early twenties.
- Males and females are equally
affected, but mean age of onset is approximately six years later in females, and females
frequently have a milder course of illness.
- The suicide rate is ten times
that of normals, and the rate is close to the rate that occurs in depressive illnesses.
- More than 75% of patients are
smokers, and an increased incidence of substance abuse has been found (especially alcohol,
cocaine, and marijuana.)
- Most do not return to baseline
functioning, and most patients follow a chronic downward course, but some have a gradual
improvement with a decrease in positive symptoms and increased functioning. Very few have
a complete recovery.
Classification
- Paranoid Type
-
- Characterized by a
preoccupation with one or more delusions or frequent auditory hallucinations.
- No prominent disorganization of
speech, disorganized or catatonic behavior, or flat or inappropriate affect.
- Disorganized Type
: Characterized by prominent disorganized speech, disorganized behavior,
and flat or inappropriate affect.
- Catatonic Type
: Characterized by at Least Two of the Following:
-
- Motoric immobility
- Excessive motor activity
- Extreme negativism or mutism
- Peculiar voluntary movements
such as bizarre posturing
- Echolalia or echopraxia
- Undifferentiated Type
: Meets criteria, but can not be characterized as paranoid, disorganized or catatonic
type.
- Residual Type :
Characterized by absence of prominent delusions, disorganized speech and grossly
disorganized or catatonic behavior and continued negative symptoms or two or more
attenuated positive symptoms.
Differential Diagnosis
- Psychotic Disorder Due
to a General Medical Condition, Delirium, or Dementia.
- Substance Induced
Psychotic Disorder: Amphetamines and cocaine frequently cause hallucinations,
paranoia, or delusions. Phencyclidine (PCP) may lead to both positive and negative
symptoms.
- Schizoaffective
Disorder: Moods symptoms are present for a significant portion of the illness. In
duration of mood symptoms is brief compared to the entire duration of the illness.
- Mood Disorder with
Psychotic Features
- Psychotic symptoms occur only
during major mood disturbance (mania or major depression).
- Disturbances of mood frequent
in all phases.