Snapshot A 47-year old man is brought to the ED by his older brother, who says that the patient has been "acting strangely and not himself" lately. Over the last 8 months, he has claimed to hear voices telling him that "he is the chosen savior of the world." He used to work as a janitor at a local elementary school but was fired recently due to his erratic behavior. On physical exam, he appears unkempt and irritated. He seems to respond to invisible stimuli, and he rambles continuously from topic to topic without a clear focus. Introduction Overview schizophrenia is a psychiatric disorder featuring periods of psychosis, commonly manifested as experiencing auditory hallucinations, delusions, and disturbed behavior with a decline in social functioning Epidemiology prevalence lifetime prevalence is approximately 1% worldwide login to view 1 more bullet demographics onset usually between age 17-35 login to view 2 more bullets risk factors marijuana use in teenagers Pathophysiology abnormalities of the dopaminergic system ↓ dopaminergic activity in the mesocortical system leads to negative symptoms ↑ dopaminergic activity in the mesolimbic system leads to positive symptoms Associated conditions brief psychotic disorder schizophrenic symptoms lasting < 1 month usually stress related schizophreniform disorder schizophrenic symptoms lasting between 1-6 months schizoaffective disorder schizophrenic symptoms with manic or depressed episode mood disturbance must be present for majority of total duration of disorder Prognosis full recovery is rare factors associated with poor prognosis early onset family history of schizophrenia structural brain abnormalities Presentation Symptoms positive symptoms auditory hallucinations delusions login to view 1 more bullet disorganized speech and behavior negative symptoms flat affect social withdrawal lack of motivations lack of speech or thought grossly catatonic behavior Physical exam diagnostic criteria for schizophrenia presence of 2 or more of the following for at least 6 months login to view 6 more bullets Studies Urine toxicology rule out reversible causes for symptoms Serum labs EKG check baseline QTc interval before starting antipsychotic complete blood count, electrolytes, liver function tests, thyroid stimulating hormone, and fasting glucose assess presence or absence of metabolic syndrome Differential Diagnosis Delusional disorder key distinguishing factors paranoid beliefs are not bizarre other symptoms of schizophrenia are not present Schizotypal personality disorder key distinguishing factor presence of odd thoughts and behaviors, though not as extreme as seen in schizophrenia Schizoid personality disorder key distinguishing factor reclusive; lack of interest in forming close relationships with others other symptoms of schizophrenia are not present Paranoid personality disorder key distinguishing factor distrustful and suspicious of others no delusions or other symptoms of schizophrenia are present Treatment Lifestyle cognitive-behavioral therapy (CBT) social skills training Medical first-generation antipsychotics chlorpromazine haloperidol perphenazine thiothixine second-generation antipsychotics aripiprazole lurasidone clozapine olanzapine quetiapine risperidone ziprasidone Complications Substance use incidence 20-70% of patients with schizophrenia risk factors younger male patients treatment dual-diagnosis treatment programs addressing alcohol and drug abuse Suicide incidence high rate in patients with schizophrenia risk factors comorbid symptoms of depression treatment addition of antidepressants to antipsychotics has mixed evidence, but may help treat the negative symptoms of chronic schizophrenia