MCCQE Common Psychiatric Disorders 2 — Questions and Answers
Question 1: A 28-year-old woman presents with recurrent episodes of binge eating followed by self-induced vomiting, dental erosions, and parotid gland enlargement. Which electrolyte abnormality is most likely?
- Hypernatremia
- Hypokalemia (Correct answer)
- Hyperkalemia
- Hypercalcemia
Correct answer: Hypokalemia
Repeated purging in bulimia nervosa causes loss of gastric acid, leading to hypokalemic, hypochloremic metabolic alkalosis.
Question 2: A 35-year-old man with schizophrenia develops high fever, muscle rigidity, diaphoresis, and altered consciousness after starting haloperidol. What is the most appropriate immediate management?
- Increase haloperidol dose
- Discontinue antipsychotic and provide supportive care (Correct answer)
- Add benztropine only
- Switch to clozapine immediately
Correct answer: Discontinue antipsychotic and provide supportive care
Neuroleptic malignant syndrome (NMS) requires immediate discontinuation of the offending antipsychotic and aggressive supportive care including IV fluids and cooling.
Question 3: A 45-year-old with MDD has failed two adequate antidepressant trials. Which augmentation strategy has the strongest evidence base for treatment-resistant depression?
- Adding lithium or atypical antipsychotic (Correct answer)
- Adding a benzodiazepine
- Switching to an MAOI without washout
- Adding methylphenidate
Correct answer: Adding lithium or atypical antipsychotic
Lithium augmentation and atypical antipsychotic augmentation (e.g., quetiapine, aripiprazole) have the best evidence for treatment-resistant depression.
Question 4: A 22-year-old college student fears being watched or judged in social situations, avoids classes, and has impaired daily functioning for over 6 months. What is the first-line pharmacological treatment?
- Diazepam
- Selective serotonin reuptake inhibitor (SSRI) (Correct answer)
- Bupropion
- Haloperidol
Correct answer: Selective serotonin reuptake inhibitor (SSRI)
SSRIs (e.g., paroxetine, sertraline) are first-line pharmacotherapy for social anxiety disorder, with evidence for both acute and long-term treatment.
Question 5: A 60-year-old man presents with a 3-week history of depressed mood, anhedonia, psychomotor retardation, and 10 lb weight loss following his wife's death 2 months ago. Which finding most supports a diagnosis of MDD rather than normal bereavement?
- Persistent tearfulness
- Marked functional impairment and suicidal ideation (Correct answer)
- Dreaming about the deceased
- Feeling sad on anniversaries
Correct answer: Marked functional impairment and suicidal ideation
Marked functional impairment and suicidal ideation distinguish major depressive disorder from normal grief, which typically does not involve suicidality.
Question 6: A 32-year-old woman with bipolar I disorder is stable on lithium and becomes pregnant. What is the primary concern regarding lithium use in the first trimester?
- Neonatal hypothyroidism
- Ebstein's anomaly risk (Correct answer)
- Neonatal seizures
- Placental abruption
Correct answer: Ebstein's anomaly risk
Lithium use in the first trimester carries a small but increased risk of Ebstein's anomaly, a cardiac malformation of the tricuspid valve.
Question 7: A 19-year-old man presents with a 6-month history of social withdrawal, flat affect, disorganized speech, and auditory hallucinations. He has no prior psychiatric history and no substance use. What is the most likely diagnosis?
- Brief psychotic disorder
- Schizophreniform disorder
- Schizophrenia (Correct answer)
- Delusional disorder
Correct answer: Schizophrenia
Schizophrenia requires at least 6 months of symptoms including at least 1 month of active-phase symptoms; this patient meets full criteria.
MCCQE Common Psychiatric Disorders 2
A 28-year-old woman presents with recurrent episodes of binge eating followed by self-induced vomiting, dental erosions, and parotid gland enlargement.
Which electrolyte abnormality is most likely?