Approach
The diagnosis is challenging, because there are no pathognomonic features and no confirmatory laboratory tests. A family history of severe mental illness, including schizophrenia, major depression, or bipolar disorder, represents an important risk factor. The characteristic feature of the disease is a combination of psychosis (i.e., delusions, hallucinations) and affective symptoms that are closely related in time but present, almost independent of each other, as clusters of symptoms. The affective symptoms are present for a significant amount of the total duration of illness.
Data on early detection and treatment are scarce, as schizoaffective disorder tends to be initially misdiagnosed as schizophrenia, bipolar disorder, or major depression before enough time lapses to clarify the diagnostic picture. However, data on schizophrenia and early-phase psychosis indicate that early detection and intervention is beneficial.[24][25][26][27] The duration of untreated psychosis appears to correlate negatively with future response to treatment and prognosis.[24]
History and examination
Conduct a thorough initial evaluation, including complete psychiatric and medical histories, as well as physical and mental status examinations on every patient with suspected schizoaffective disorder.[1]
Patients may present with or have a history of features including the following:
Schizophrenia symptoms
Positive symptoms:
Symptoms that are in excess of what is considered to be normal functioning
Includes hallucinations, delusional ideation, thought disorder, and bizarre behaviour
Delusions or hallucinations occur for ≥2 weeks in absence of depressive or manic symptoms.[1]
Negative symptoms:
Symptoms that are the result of a deficit in what is considered to be normal functioning
Examples include anhedonia, amotivation, social isolation, or flat affect.
Disturbances in emotion or incongruent affect:
Anxiety, depression, elation, and perplexity can occur at any time during the course of the illness
Incongruent affect is also common and refers to non-congruence between thought and speech content
These occur more commonly in patients with schizoaffective disorder than in schizophrenia.
Mood symptoms
Major mood episodes (either major depression or mania) must occur for at least half the time the patient has met criteria for schizophrenia.[1]
Features of major depressive episodes include:
Depressed mood, lack of interest/pleasure, weight changes, insomnia or hypersomnia, psychomotor agitation or retardation, fatigue, feelings of worthlessness or guilt, decreased concentration, suicidal ideation
Symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.
Features of manic episodes include:
Inflated self-esteem, decreased need for sleep, increased talkativeness, racing thoughts, distracted easily, increase in goal-directed activity or psychomotor agitation, engaging in activities that hold the potential for harmful consequences.
Other perceptual experiences such as derealisation and déjà vu are possible but, if prominent, a magnetic resonance imaging (MRI) scan should be considered to exclude structural brain lesions.
Neurological examination does not usually reveal gross neurological deficit. 'Soft signs' (minor neurological findings) are found in over half of patients with schizophrenia (and probably schizoaffective disorder) and in a considerable number of their blood relatives. Deficits may be found in motor co-ordination, smooth-pursuit eye movement, sensory integration, right-left orientation, and other areas.[28][29] The clinical value of these findings is very limited. However, one study suggests the presence of primary motor co-ordination dysfunction on initial presentation may be associated with a more severe non-remitting course and may help identify patients who would benefit from early, more assertive treatment approaches.[30]
Social and occupational functioning is commonly impaired; however, this is not a defining criterion for schizoaffective disorder. These impairments may be less severe and persistent than in schizophrenia.[31]
Risk assessment
As with patients with schizophrenia, bipolar disorder, and depression, patients diagnosed with schizoaffective disorder should undergo a comprehensive assessment of risk to themselves and to others.[32][33]
A suicide risk assessment should include factors that increase the risk of suicide (such as previous attempts, stressors, substance misuse, agitation, depression, low self-esteem, family history of mental illness), as well as protective factors (social support, caring for children, religious factors). It is paramount to assess suicidal ideation, as well as intent and plan, if present. See Suicide risk mitigation.
A prior history of violence, hostile emotion such as anger or suspiciousness, persecutory delusions, or commanding hallucinations are all risk factors for harm to others.[32]
Collateral information
As many patients are unable to provide a reliable history at the time of the initial examination, interviews of family members, or other people who know the patient, should be part of the routine work-up.[34]
Medical work-up
A thorough medical work-up is recommended for a patient presenting with a first episode of psychosis, mania, or depression. This should include a urine or blood test for illicit drugs, and a list of current prescribed, over-the-counter, and supplement medications should be reviewed to help to rule out a chemically induced psychosis. Blood work should be ordered to rule out metabolic and electrolyte abnormalities that might either produce or contribute to the presentation. Infections, including sexually transmitted infections, should be screened for.
Based on the history and examination findings, additional electrophysiological and radiological assessments (including head computed tomography or magnetic resonance imaging) might be considered on a case-by-case basis.[35]
A pregnancy test is recommended for women of childbearing potential.
As many of the antipsychotic drugs recommended for schizoaffective disorder increase the risk for metabolic syndrome, measurement of body weight and vital signs (heart rate, blood pressure, temperature), as well as a metabolic panel including glucose, cholesterol, and triglycerides are recommended. An ECG and tests of liver and kidney function are important in informing the decision about recommended antipsychotic agents.[35]
Numerous medical conditions can cause psychiatric symptoms. Rarely, herpes simplex virus polymerase chain reaction (HSV-PCR) in cerebrospinal fluid, liver function tests, copper urine level and serum ceruloplasmin, vitamin B12 levels, lupus screen, chromosomal studies, and porphobilinogen tests are used to clarify the underlying pathology.
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