Sub-types:Several subtypes are defined according to the presence or absence of typical ‘polymorphic features’ and schizophrenic first‐rank symptoms.
- Acute polymorphic psychotic disorder without symptoms of schizophrenia (M/C) (<3 months)
- Acute polymorphic psychotic disorder with symptoms of schizophrenia (<1 month)
- Acute schizophrenia-like psychotic disorder (<1 month)
- Other acute predominantly delusional psychotic disorders (<3 months)
- Other acute and transient psychotic disorders (<3 months)
- Acute and transient psychotic disorders, unspecified (<3 months)
Differentiating factors from schizophrenia:As a group, ATPD has different pattern of illness risk compared to schizophrenia, and different subtypes of ATPD may be genetically heterogeneous.
- ATPD is consistently reported to occur in females between early and middle adulthood.
- Patients affected with ATPD do not have significant pre-morbid dysfunctions. They are more likely to experience shifting polymorphic features, e.g., hallucinations or delusions of different type, which usually change in either content or intensity from day to day or within the same day.