Schizophrenia for USMLE Step 1 / COMLEX-USA Level 1

• Pathophysiology: Involves dopamine dysregulation, particularly in the mesolimbic and mesocortical pathways, and glutamatergic dysfunction.

• Symptoms:
• Positive Symptoms: Hallucinations (typically auditory), delusions, and disorganized speech.
• Negative Symptoms: Flat affect, anhedonia, apathy, social withdrawal.
• Cognitive Symptoms: Impaired executive function, attention, and working memory.
• Diagnostic Criteria: Symptoms persisting for at least 6 months, with significant impact on social or occupational functioning.

• Similar to Schizophrenia: Presents with identical symptoms.
• Duration: Symptoms last more than 1 month but less than 6 months.
• Prognosis: Potential for full recovery after an episode or progression to schizophrenia.

• Duration: Sudden onset of symptoms lasting more than 1 day but less than 1 month.
• Symptoms: Includes hallucinations, delusions, or disorganized speech.
• Recovery: Full return to pre-episode level of functioning, often triggered by extreme stress or trauma.

• Features: Concurrent symptoms of schizophrenia and a mood disorder (depression or bipolar disorder).
• Diagnosis: Psychotic symptoms must occur in the absence of mood disorder symptoms at some point during the illness.

• Symptoms: Presence of one or more delusions for at least 1 month.
• Functioning: Apart from the impact of the delusions, functioning is not markedly impaired, and behavior is not obviously odd or bizarre.

• Definition: Delusions shared between two people, typically close family members or partners.
• Context: Develops in the context of a close relationship with someone who has a psychotic disorder with prominent delusions.

• Antipsychotic Medications:
• Typical Antipsychotics: Block dopamine D2 receptors, effective primarily for positive symptoms.
• Atypical Antipsychotics: Affect both dopamine and serotonin receptors, addressing both positive and negative symptoms.
• Side Effects:
• Typical Antipsychotics: Extrapyramidal symptoms, tardive dyskinesia.
• Atypical Antipsychotics: Weight gain, diabetes, dyslipidemia.

See the following tutorial for details on Antipsychotics. 1. Dopamine and Glutamate Pathways: Understanding the neurotransmitter systems involved in psychotic disorders. 2. Diagnosis and Criteria: Knowing the time criteria and symptomatology that distinguish schizophrenia, schizophreniform, and brief psychotic disorders. 3. Pharmacological Management: Mechanisms and side effects of typical vs. atypical antipsychotics. 4. Neuroanatomy and Imaging: Changes in brain structure associated with chronic schizophrenia, such as ventricular enlargement.