COMAT Psychiatry Exam V3 | COMAT Psychiatry |
Q&A with Rationale (COMAT Psychiatry Exam) |
National Board of Osteopathic Medical Examiners
(NBOME)
1. A 24-year-old male is brought to the emergency department by his roommate who states
the patient has not slept in four days. The patient is speaking rapidly, jumping from one topic
to another, and claims he is about to revolutionize the energy industry with a new invention.
His roommate notes this behavior started a week ago. The patient has no significant past
medical history and takes no medications. Physical examination shows a pulse of 105/min
and blood pressure of 135/85 mmHg. Urine toxicology is negative. Which of the following is
the most likely diagnosis?
A. Cyclothymic disorder
B. Bipolar I disorder
C. Bipolar II disorder
D. Schizoaffective disorder
Correct Answer: B
Explanation: Bipolar I disorder requires at least one manic episode, which is defined by a
distinct period of abnormally elevated or irritable mood and increased energy lasting at
least one week. Manic episodes often involve decreased need for sleep, pressured speech,
,and grandiosity as seen in this patient. Unlike Bipolar II, Bipolar I does not require a history
of major depressive episodes, although they are common.
2. A 19-year-old college student presents to the student health clinic reporting that for the
past 3 weeks, he has felt ‘on edge’ and is unable to concentrate on his studies. He mentions
hearing a voice calling his name when no one is around and believes his professors are
monitoring his internet activity to sabotage his grades. He denies any changes in mood or
substance use. Which of the following is the most appropriate diagnosis?
A. Schizophrenia
B. Delusional disorder
C. Brief psychotic disorder
D. Schizophreniform disorder
Correct Answer: D
Explanation: Schizophreniform disorder is characterized by the same symptomatic
criteria as schizophrenia but lasts at least one month but less than six months. This
patient’s symptoms (hallucinations and delusions) have lasted 3 weeks, fitting this window
if they continue past one month; however, currently, the presentation is consistent with the
early stage of schizophreniform. If symptoms persist beyond six months, the diagnosis
would be updated to schizophrenia.
,3. A 45-year-old female with a long history of bipolar disorder is brought to the clinic for a
routine follow-up. She complains of increased thirst and frequent urination over the last two
months. Laboratory studies show a serum sodium of 148 mEq/L and a low urine osmolality
that does not increase significantly with administration of exogenous vasopressin. Which of
the following medications is most likely responsible for these findings?
A. Lithium
B. Valproate
C. Quetiapine
D. Lamotrigine
Correct Answer: A
Explanation: Lithium is a well-known cause of nephrogenic diabetes insipidus (DI), where
the kidneys become resistant to antidiuretic hormone (ADH). This results in polyuria,
polydipsia, and hypernatremia as seen in this patient. Management involves monitoring
lithium levels and potentially switching to another mood stabilizer or adding amiloride to
block lithium entry into the collecting duct cells.
4. A 32-year-old female is evaluated in the emergency department for high fever, muscle
rigidity, and confusion. She was recently started on haloperidol for acute agitation. Her
temperature is 104.2 F, heart rate is 120/min, and blood pressure is 160/95 mmHg.
Laboratory results show a significantly elevated creatine kinase level. What is the most likely
diagnosis?
A. Neuroleptic malignant syndrome
, B. Serotonin syndrome
C. Malignant hyperthermia
D. Anticholinergic toxicity
Correct Answer: A
Explanation: Neuroleptic malignant syndrome (NMS) is a life-threatening reaction to
dopamine antagonists, most commonly high-potency first-generation antipsychotics like
haloperidol. Key features include the ‘tetrad’ of mental status changes, muscular rigidity
(lead-pipe), hyperthermia, and autonomic instability. Treatment involves stopping the
offending agent and supportive care, with bromocriptine or dantrolene used in severe
cases.
5. A 22-year-old female presents to the outpatient clinic for evaluation of unstable
relationships and frequent mood swings. She describes feeling ‘empty’ and admits to
recurrent self-harm when she feels abandoned by friends. During the interview, she initially
praises the physician as ‘the best doctor in the world’ but becomes intensely angry when told
the appointment time is almost up. Which personality disorder is most likely?
A. Histrionic personality disorder
B. Narcissistic personality disorder
C. Borderline personality disorder
D. Antisocial personality disorder
Correct Answer: C
Q&A with Rationale (COMAT Psychiatry Exam) |
National Board of Osteopathic Medical Examiners
(NBOME)
1. A 24-year-old male is brought to the emergency department by his roommate who states
the patient has not slept in four days. The patient is speaking rapidly, jumping from one topic
to another, and claims he is about to revolutionize the energy industry with a new invention.
His roommate notes this behavior started a week ago. The patient has no significant past
medical history and takes no medications. Physical examination shows a pulse of 105/min
and blood pressure of 135/85 mmHg. Urine toxicology is negative. Which of the following is
the most likely diagnosis?
A. Cyclothymic disorder
B. Bipolar I disorder
C. Bipolar II disorder
D. Schizoaffective disorder
Correct Answer: B
Explanation: Bipolar I disorder requires at least one manic episode, which is defined by a
distinct period of abnormally elevated or irritable mood and increased energy lasting at
least one week. Manic episodes often involve decreased need for sleep, pressured speech,
,and grandiosity as seen in this patient. Unlike Bipolar II, Bipolar I does not require a history
of major depressive episodes, although they are common.
2. A 19-year-old college student presents to the student health clinic reporting that for the
past 3 weeks, he has felt ‘on edge’ and is unable to concentrate on his studies. He mentions
hearing a voice calling his name when no one is around and believes his professors are
monitoring his internet activity to sabotage his grades. He denies any changes in mood or
substance use. Which of the following is the most appropriate diagnosis?
A. Schizophrenia
B. Delusional disorder
C. Brief psychotic disorder
D. Schizophreniform disorder
Correct Answer: D
Explanation: Schizophreniform disorder is characterized by the same symptomatic
criteria as schizophrenia but lasts at least one month but less than six months. This
patient’s symptoms (hallucinations and delusions) have lasted 3 weeks, fitting this window
if they continue past one month; however, currently, the presentation is consistent with the
early stage of schizophreniform. If symptoms persist beyond six months, the diagnosis
would be updated to schizophrenia.
,3. A 45-year-old female with a long history of bipolar disorder is brought to the clinic for a
routine follow-up. She complains of increased thirst and frequent urination over the last two
months. Laboratory studies show a serum sodium of 148 mEq/L and a low urine osmolality
that does not increase significantly with administration of exogenous vasopressin. Which of
the following medications is most likely responsible for these findings?
A. Lithium
B. Valproate
C. Quetiapine
D. Lamotrigine
Correct Answer: A
Explanation: Lithium is a well-known cause of nephrogenic diabetes insipidus (DI), where
the kidneys become resistant to antidiuretic hormone (ADH). This results in polyuria,
polydipsia, and hypernatremia as seen in this patient. Management involves monitoring
lithium levels and potentially switching to another mood stabilizer or adding amiloride to
block lithium entry into the collecting duct cells.
4. A 32-year-old female is evaluated in the emergency department for high fever, muscle
rigidity, and confusion. She was recently started on haloperidol for acute agitation. Her
temperature is 104.2 F, heart rate is 120/min, and blood pressure is 160/95 mmHg.
Laboratory results show a significantly elevated creatine kinase level. What is the most likely
diagnosis?
A. Neuroleptic malignant syndrome
, B. Serotonin syndrome
C. Malignant hyperthermia
D. Anticholinergic toxicity
Correct Answer: A
Explanation: Neuroleptic malignant syndrome (NMS) is a life-threatening reaction to
dopamine antagonists, most commonly high-potency first-generation antipsychotics like
haloperidol. Key features include the ‘tetrad’ of mental status changes, muscular rigidity
(lead-pipe), hyperthermia, and autonomic instability. Treatment involves stopping the
offending agent and supportive care, with bromocriptine or dantrolene used in severe
cases.
5. A 22-year-old female presents to the outpatient clinic for evaluation of unstable
relationships and frequent mood swings. She describes feeling ‘empty’ and admits to
recurrent self-harm when she feels abandoned by friends. During the interview, she initially
praises the physician as ‘the best doctor in the world’ but becomes intensely angry when told
the appointment time is almost up. Which personality disorder is most likely?
A. Histrionic personality disorder
B. Narcissistic personality disorder
C. Borderline personality disorder
D. Antisocial personality disorder
Correct Answer: C
