Differential diagnosis of schizophrenia

Abstract

Schizophrenia is one of the 1st diagnoses that should come to mind when a clinician encounters a patient experiencing delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior, or negative symptoms. However, the clinician must keep in mind that there is no one pathognomonic feature of schizophrenia. Since psychosis can be a symptom of various psychiatric and medical/neurological illnesses and can be related to medications, alcohol, and illegal drugs, the evaluation of a patient with an acute episode of psychosis should begin with the formulation of a broad differential diagnosis. This chapter focuses on differentiating schizophrenia from other psychiatric and medical/neurological illnesses and substance-induced psychotic disorders. Psychiatric illnesses that must be excluded prior to diagnosing schizophrenia include: schizophreniform disorder, schizoaffective disorder, affective disorders, depresion in schizophrenia, delusional disorder, brief reactive psychosis, psychosis not otherwise specified, personality disorders, (PsycInfo Database Record (c) 2022 APA, all rights reserved)