A 14-year-old girl presents to her pediatrician with complaints of repeated jerking of her neck for the past 2 years. Initially, her parents considered it a sign of discomfort in her neck, but later they noticed that the jerking was more frequent when she was under emotional stress or when she was fatigued. The patient says she can voluntarily control the jerking in some social situations, but when she is under stress, she feels the urge to jerk her neck and she feels better after that. The parents also report occasional throat clearing and brief vocal sounds that seem involuntary. During the past year, there have been a few weeks when the frequency of both the neck jerking and vocal sounds decreased drastically, only to increase again afterwards. On physical examination, she is a physically healthy female with normal vital signs. Her neurologic examination is normal. The pediatrician also notes that when he makes certain movements, the patient partially imitates these movements. The parents are very concerned about her abnormal movements and insist on a complete diagnostic work-up. After a detailed history, physical examination, and laboratory investigations, the pediatrician confirms the diagnosis of Tourette syndrome. The presence of which of the following findings is most likely to confirm the pediatrician's diagnosis?
Q62
An 83-year-old man is being seen in the hospital for confusion. The patient was admitted 4 days ago for pneumonia. He has been improving on ceftriaxone and azithromycin. Then 2 nights ago he had an episode of confusion. He was unsure where he was and attempted to leave. He was calmed down by nurses with redirection. He had a chest radiograph that was stable from admission, a normal EKG, and a normal urinalysis. This morning he was alert and oriented. Then this evening he became confused and agitated again. The patient has a history of benign prostatic hyperplasia, severe dementia, and osteoarthritis. He takes tamsulosin in addition to the newly started antibiotics. Upon physical examination, the patient is alert but orientated only to name. He tries to get up, falls back onto the bed, and grabs his right knee. He states, “I need to get to work. My boss is waiting, but my knee hurts.” He tries to walk again, threatens the nurse who stops him, and throws a plate at the wall. In addition to reorientation, which of the following is the next best step in management?
Q63
A 21-year-old male college student is brought to the emergency department by the campus police after he was found yelling at a bookshelf in the library. His roommate does not know of any prior episodes similar to this. His vital signs are within normal limits. The patient appears unkempt. On mental status examination, he talks very fast with occasional abrupt interruptions. He is agitated. He is disoriented to time and repeatedly tells the physician, “I hear the sun telling me that I was chosen to save the universe.” Urine toxicology screen is negative. Which of the following is the most appropriate pharmacotherapy?
Q64
A 17-year-old boy is brought to the physician by his parents who are concerned about his bizarre behavior. Over the past three months, he has become withdrawn from his friends and less interested in his classes and extracurricular activities. On several occasions, he has torn apart rooms in their home looking for “bugs” and states that the President is spying on him because aliens have told the government that he is a threat. Although he has always been quite clean in the past, his father notes that the patient’s room is now malodorous with clothes and dishes strewn about haphazardly. He also says that sometimes he can hear the devil speaking to him from inside his head. He has no medical problems, does not drink alcohol or use any drugs. Physical examination of the boy reveals no abnormalities. On mental status examination, the boy is oriented to person, place and time. He avoids eye contact and replies mostly with monosyllabic responses. He appears distracted, and confirms that he is hearing whispering voices in his head. What is the most appropriate diagnosis for this patient?
Q65
A 26-year-old man is brought to the emergency department by his wife because of bizarre and agitated behavior for the last 6 weeks. He thinks that the NSA is spying on him and controlling his mind. His wife reports that the patient has become withdrawn and at times depressed for the past 3 months. He lost his job because he stopped going to work 4 weeks ago. Since then, he has been working on an invention that will block people from being able to control his mind. Physical and neurologic examinations show no abnormalities. On mental status examination, he is confused and suspicious with marked psychomotor agitation. His speech is disorganized and his affect is labile. Which of the following is the most likely diagnosis?
Q66
A 42-year-old woman is brought to the physician by her husband because of a 1-year history of abnormal behavior. During this time she has been irritable, restless, and has had multiple episodes of hearing voices. Over the past month, she has also had difficulty swallowing. She has a 2-year history of depression. She was let go by her employer 6 months ago because she could no longer handle all her tasks and often forgot about assignments. Her father committed suicide at the age of 50. The patient has smoked one pack of cigarettes daily over the past 20 years. She has a history of smoking cocaine for 8 years but stopped 1 year ago. Vital signs are within normal limits. On mental status examination, she is confused and oriented to person and place only. Neurologic examination shows a delayed return to neutral ankle position after triggering the plantar reflex. Physical examination shows irregular, nonrepetitive, and arrhythmic movements of the neck and head. The patient has poor articulation. Which of the following is the most likely diagnosis?
Q67
A 60-year-old man presents to the emergency department with a rapid change in his behavior. The patient recently returned from a vacation in rural Mexico and recovered from several episodes of bloody diarrhea. He has had a notable and rapid decline in his memory which started this morning. His personality has also changed, has not been sleeping, and seems generally apathetic. Brief and involuntary muscle twitches have been noted as well. The patient has a past medical history of hypertension and diabetes. His temperature is 99.8°F (37.7°C), blood pressure is 152/98 mmHg, pulse is 97/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam is notable for a confused and apathetic man who is not compliant with the neurological exam. The patient is admitted to the ICU; however, during his hospital course, the patient ultimately dies. Which of the following was most likely to be found in this patient upon initial presentation?
Q68
A 22-year-old man is brought to the physician by his mother because of concerns about his recent behavior. Three months ago, the patient first reported hearing loud voices coming from the ceiling of his room. During this time, he has also become increasingly worried that visitors to the house were placing secret surveillance cameras. Mental status examination shows tangential speech with paranoid thoughts. Treatment for this patient's condition predominantly targets which of the following dopaminergic pathways?
Q69
A 34-year-old man presents to the behavioral health clinic for an evaluation after seeing animal-shaped clouds in the form of dogs, cats, and monkeys. The patient says that these symptoms have been present for more than 2 weeks. Past medical history is significant for simple partial seizures for which he takes valproate, but he has not had his medication adjusted in several years. His vital signs include: blood pressure of 124/76 mm Hg, heart rate of 98/min, respiratory rate of 12/min, and temperature of 37.1°C (98.8°F). On physical examination, the patient is alert and oriented to person, time, and place. Affect is not constricted or flat. Speech is of rapid rate and high volume. Pupils are equal and reactive bilaterally. The results of a urine drug screen are as follows:
Alcohol positive
Amphetamine negative
Benzodiazepine negative
Cocaine positive
GHB negative
Ketamine negative
LSD negative
Marijuana negative
Opioids negative
PCP negative
Which of the following is the most likely diagnosis in this patient?
Q70
A 58-year-old right-handed man is brought to the emergency department after he was found unconscious in his living room by his wife. She reports that he has never had a similar episode before. The patient has hypertension and consumes multiple alcoholic drinks per day. On arrival, he is confused and oriented only to person. He cannot recall what happened. He has difficulty speaking and his words are slurred. He reports a diffuse headache and muscle pain and appears fatigued. His temperature is 37°C (98.6°F), pulse is 85/min, respirations are 14/min, and blood pressure is 135/70 mm Hg. Examination shows a 2-cm bruise on his right shoulder. Strength is 5/5 throughout, except for 1/5 in the left arm. The remainder of the physical examination shows no abnormalities. An ECG shows left ventricular hypertrophy. A CT scan of the head without contrast shows no abnormalities. Which of the following is the most likely underlying cause of this patient's symptoms?
Psychotic Disorders US Medical PG Practice Questions and MCQs
Question 61: A 14-year-old girl presents to her pediatrician with complaints of repeated jerking of her neck for the past 2 years. Initially, her parents considered it a sign of discomfort in her neck, but later they noticed that the jerking was more frequent when she was under emotional stress or when she was fatigued. The patient says she can voluntarily control the jerking in some social situations, but when she is under stress, she feels the urge to jerk her neck and she feels better after that. The parents also report occasional throat clearing and brief vocal sounds that seem involuntary. During the past year, there have been a few weeks when the frequency of both the neck jerking and vocal sounds decreased drastically, only to increase again afterwards. On physical examination, she is a physically healthy female with normal vital signs. Her neurologic examination is normal. The pediatrician also notes that when he makes certain movements, the patient partially imitates these movements. The parents are very concerned about her abnormal movements and insist on a complete diagnostic work-up. After a detailed history, physical examination, and laboratory investigations, the pediatrician confirms the diagnosis of Tourette syndrome. The presence of which of the following findings is most likely to confirm the pediatrician's diagnosis?
A. Decreased caudate volumes in magnetic resonance imaging (MRI) of the brain
B. Rigidity and bradykinesia
C. History of repeated bouts of unprovoked obscene speech over the past year (Correct Answer)
D. Increased activity in frontal subcortical regions in positron-emission tomography (PET) study
E. Low serum ceruloplasmin level
Explanation: ***History of repeated bouts of unprovoked obscene speech over the past year***
- **Coprolalia** (involuntary obscene speech) is a **complex vocal tic** that, when present, is **highly specific for Tourette syndrome** and strongly supports the diagnosis.
- While coprolalia is **NOT required for diagnosis** (present in only 10-15% of Tourette patients), its presence in the context of motor and vocal tics is **highly characteristic** and distinguishes Tourette syndrome from other tic disorders.
- The clinical vignette already demonstrates the **DSM-5 diagnostic criteria**: multiple motor tics plus vocal tics for >1 year with onset before age 18, making coprolalia an **additional supportive feature** rather than necessary for diagnosis.
- Among the options provided, coprolalia is the **most clinically relevant finding** that would further support the Tourette syndrome diagnosis.
*Decreased caudate volumes in magnetic resonance imaging (MRI) of the brain*
- While structural brain changes including **reduced caudate volumes** have been observed in research studies of Tourette syndrome, these findings are **not diagnostic** or consistently present across all patients.
- Neuroimaging is typically used to **rule out secondary causes** of tics (e.g., structural lesions, stroke) rather than to confirm Tourette syndrome, which remains a **clinical diagnosis**.
*Rigidity and bradykinesia*
- **Rigidity and bradykinesia** are cardinal features of **Parkinson's disease** and other parkinsonian syndromes, not Tourette syndrome.
- Tourette syndrome involves **tics** (sudden, rapid, recurrent, non-rhythmic movements or vocalizations), which are phenomenologically distinct from parkinsonian features.
*Increased activity in frontal subcortical regions in positron-emission tomography (PET) study*
- Functional neuroimaging may show abnormalities in **basal ganglia-thalamocortical circuits** in Tourette syndrome, but these are **research findings** not used in clinical practice.
- PET scans are **not part of diagnostic criteria** and lack the specificity needed to confirm Tourette syndrome, which is diagnosed based on clinical history and examination.
*Low serum ceruloplasmin level*
- A **low serum ceruloplasmin level** is diagnostic of **Wilson's disease**, a genetic disorder of copper metabolism that can present with neuropsychiatric symptoms and movement disorders.
- Wilson's disease typically presents with tremor, dystonia, and parkinsonian features—not the tic pattern described in this case—and usually includes hepatic involvement.
Question 62: An 83-year-old man is being seen in the hospital for confusion. The patient was admitted 4 days ago for pneumonia. He has been improving on ceftriaxone and azithromycin. Then 2 nights ago he had an episode of confusion. He was unsure where he was and attempted to leave. He was calmed down by nurses with redirection. He had a chest radiograph that was stable from admission, a normal EKG, and a normal urinalysis. This morning he was alert and oriented. Then this evening he became confused and agitated again. The patient has a history of benign prostatic hyperplasia, severe dementia, and osteoarthritis. He takes tamsulosin in addition to the newly started antibiotics. Upon physical examination, the patient is alert but orientated only to name. He tries to get up, falls back onto the bed, and grabs his right knee. He states, “I need to get to work. My boss is waiting, but my knee hurts.” He tries to walk again, threatens the nurse who stops him, and throws a plate at the wall. In addition to reorientation, which of the following is the next best step in management?
A. Morphine
B. Lorazepam
C. Haloperidol (Correct Answer)
D. Rivastigmine
E. Physical restraints
Explanation: ***Haloperidol***
- The patient exhibits **delirium** with acute agitation, threatening behavior, and violent actions (throwing objects), representing an **imminent safety risk** to himself and staff.
- After **non-pharmacological interventions** (reorientation) have failed, **low-dose haloperidol** is appropriate for managing **severe agitation** in delirium when there is risk of harm.
- While antipsychotics have an FDA black box warning for increased mortality in elderly patients with dementia and recent evidence questions their efficacy in delirium, they remain indicated for **acute agitation with safety concerns** as a short-term intervention.
- Haloperidol is preferred over atypical antipsychotics in acute hospital settings due to availability in parenteral forms and lower anticholinergic burden.
*Morphine*
- While the patient mentions knee pain (likely from osteoarthritis), his **primary issue** is acute agitation and delirium, not pain management.
- **Opioids** can worsen delirium and confusion in elderly patients through anticholinergic effects and sedation.
- Pain should be addressed, but not as the primary intervention for violent, agitated behavior.
*Lorazepam*
- **Benzodiazepines** are generally **contraindicated in delirium** as they worsen confusion, increase fall risk, and can cause paradoxical agitation in elderly patients.
- The **only exceptions** are delirium from alcohol or benzodiazepine withdrawal, or seizures—none of which apply to this patient.
- Lorazepam would likely exacerbate rather than improve this patient's mental status.
*Rivastigmine*
- **Rivastigmine** is an acetylcholinesterase inhibitor for chronic management of **dementia symptoms**, not acute delirium.
- It has **no role** in managing acute behavioral disturbances and takes weeks to show any effect.
- Studies have not shown benefit of cholinesterase inhibitors in preventing or treating delirium.
*Physical restraints*
- Physical restraints should be used only as a **last resort** when pharmacological and non-pharmacological interventions have failed and there is immediate, serious risk of harm.
- Restraints can **increase agitation**, cause injuries, lead to delirium worsening, and are associated with increased morbidity and mortality.
- They do not address the underlying cause and should be avoided when other options are available.
Question 63: A 21-year-old male college student is brought to the emergency department by the campus police after he was found yelling at a bookshelf in the library. His roommate does not know of any prior episodes similar to this. His vital signs are within normal limits. The patient appears unkempt. On mental status examination, he talks very fast with occasional abrupt interruptions. He is agitated. He is disoriented to time and repeatedly tells the physician, “I hear the sun telling me that I was chosen to save the universe.” Urine toxicology screen is negative. Which of the following is the most appropriate pharmacotherapy?
A. Alprazolam
B. Valproic acid
C. Dexmedetomidine
D. Haloperidol (Correct Answer)
E. Ziprasidone
Explanation: ***Haloperidol***
- This patient presents with acute **psychosis** characterized by **auditory hallucinations**, **disorganized speech**, and **agitation**, making an **antipsychotic** the most appropriate initial treatment.
- **Haloperidol** is a potent **first-generation antipsychotic** effective for rapid tranquilization in acute psychotic episodes due to its fast onset of action and available parenteral formulation.
- It remains a widely used option for acute agitation with psychosis, particularly when rapid control is needed.
*Alprazolam*
- **Alprazolam** is a **benzodiazepine** primarily used for anxiety and panic disorders, acting as a CNS depressant.
- While it can reduce agitation, it does not directly address the underlying psychotic symptoms (hallucinations, delusions) and could exacerbate disorientation in a psychotic patient.
*Valproic acid*
- **Valproic acid** is a **mood stabilizer** and anticonvulsant, primarily used for bipolar disorder and epilepsy.
- It is not an appropriate first-line treatment for acute psychosis or agitation when the primary issue is psychotic symptoms, as its onset of action is slower for acute behavioral control.
*Dexmedetomidine*
- **Dexmedetomidine** is an alpha-2 adrenergic agonist used for sedation, particularly in ICU settings, that provides sedation without significant respiratory depression.
- While it could sedate this agitated patient, it does not treat the underlying psychosis and is generally not the first choice for agitation in acute psychiatric emergencies due to its primary action as a sedative rather than an antipsychotic.
*Ziprasidone*
- **Ziprasidone** is a **second-generation antipsychotic** that effectively treats psychosis and is available in both oral and IM formulations.
- While ziprasidone IM has rapid onset and is commonly used for acute agitation with psychosis, **haloperidol** has longer historical use and more extensive clinical experience in emergency settings for rapid tranquilization, though both are appropriate choices.
- Ziprasidone may cause QT prolongation, requiring ECG monitoring in some patients.
Question 64: A 17-year-old boy is brought to the physician by his parents who are concerned about his bizarre behavior. Over the past three months, he has become withdrawn from his friends and less interested in his classes and extracurricular activities. On several occasions, he has torn apart rooms in their home looking for “bugs” and states that the President is spying on him because aliens have told the government that he is a threat. Although he has always been quite clean in the past, his father notes that the patient’s room is now malodorous with clothes and dishes strewn about haphazardly. He also says that sometimes he can hear the devil speaking to him from inside his head. He has no medical problems, does not drink alcohol or use any drugs. Physical examination of the boy reveals no abnormalities. On mental status examination, the boy is oriented to person, place and time. He avoids eye contact and replies mostly with monosyllabic responses. He appears distracted, and confirms that he is hearing whispering voices in his head. What is the most appropriate diagnosis for this patient?
A. Schizophrenia
B. Schizoid personality type
C. Brief psychotic disorder
D. Schizophreniform disorder (Correct Answer)
E. Schizoaffective disorder
Explanation: ***Schizophreniform disorder***
- The patient exhibits core **psychotic symptoms** (delusions, hallucinations, disorganized thinking) for at least three months, but the duration is less than six months.
- The presence of social and occupational dysfunction, along with prominent psychotic features like **paranoid delusions** and **auditory hallucinations**, is consistent with this diagnosis.
*Schizophrenia*
- Requires continuous signs of the disturbance for at least **six months**, including at least one month of active-phase symptoms.
- While the symptoms are consistent with schizophrenia, the **duration criterion** of six months has not yet been met.
*Schizoid personality type*
- Characterized by a pervasive pattern of **detachment from social relationships** and a restricted range of emotional expression.
- This patient's symptoms are primarily **psychotic** (delusions, hallucinations) and represent a significant change in functioning, not merely a personality style.
*Brief psychotic disorder*
- Characterized by the sudden onset of **psychotic symptoms** that last at least one day but **less than one month**.
- The patient's symptoms have been ongoing for **three months**, exceeding the criteria for brief psychotic disorder.
*Schizoaffective disorder*
- Involves a period of illness during which there is an uninterrupted major mood episode (depressive or manic) concurrent with Criterion A of schizophrenia.
- There is no mention of concurrent **major mood episodes** (mania or severe depression) in this patient's presentation.
Question 65: A 26-year-old man is brought to the emergency department by his wife because of bizarre and agitated behavior for the last 6 weeks. He thinks that the NSA is spying on him and controlling his mind. His wife reports that the patient has become withdrawn and at times depressed for the past 3 months. He lost his job because he stopped going to work 4 weeks ago. Since then, he has been working on an invention that will block people from being able to control his mind. Physical and neurologic examinations show no abnormalities. On mental status examination, he is confused and suspicious with marked psychomotor agitation. His speech is disorganized and his affect is labile. Which of the following is the most likely diagnosis?
A. Brief psychotic disorder
B. Schizophreniform disorder (Correct Answer)
C. Schizotypal personality disorder
D. Schizophrenia
E. Delusional disorder
Explanation: ***Schizophreniform disorder***
- The patient's symptoms, including **delusions** (fixed false beliefs that the NSA is spying and controlling his mind), **disorganized speech**, and **agitated behavior**, are consistent with a psychotic disorder.
- The duration of active psychotic symptoms (6 weeks), which is more than 1 month but less than 6 months, fits the diagnostic criteria for **schizophreniform disorder**.
- The prodromal phase (withdrawn and depressed for 3 months) plus the active phase does not yet meet the 6-month requirement for schizophrenia.
*Brief psychotic disorder*
- This disorder is characterized by a sudden onset of psychotic symptoms lasting less than 1 month, followed by a full return to premorbid functioning.
- The patient's active psychotic symptoms have persisted for 6 weeks, exceeding the maximum duration for brief psychotic disorder.
*Schizotypal personality disorder*
- This disorder primarily involves a pervasive pattern of social and interpersonal deficits marked by acute discomfort with close relationships, as well as cognitive or perceptual distortions and eccentricities.
- While there might be odd beliefs or magical thinking, it does not typically involve the persistent and severe delusions and disorganized speech seen in this case.
- This is a personality disorder, not a psychotic disorder.
*Schizophrenia*
- Schizophrenia requires continuous signs of disturbance for at least 6 months, which includes at least 1 month of active-phase symptoms (delusions, hallucinations, disorganized speech).
- The patient's total duration of illness (3 months of prodromal symptoms plus 6 weeks of active symptoms) totals approximately 4.5 months, which is less than the 6-month minimum duration required for a diagnosis of schizophrenia.
*Delusional disorder*
- The primary feature of delusional disorder is the presence of one or more delusions for at least 1 month, without other prominent psychotic symptoms such as disorganized speech or behavior.
- This patient exhibits prominent **disorganized speech**, **labile affect**, and **disorganized behavior** (bizarre invention work), which are not characteristic of delusional disorder.
- Functioning is more impaired than typically seen in delusional disorder.
Question 66: A 42-year-old woman is brought to the physician by her husband because of a 1-year history of abnormal behavior. During this time she has been irritable, restless, and has had multiple episodes of hearing voices. Over the past month, she has also had difficulty swallowing. She has a 2-year history of depression. She was let go by her employer 6 months ago because she could no longer handle all her tasks and often forgot about assignments. Her father committed suicide at the age of 50. The patient has smoked one pack of cigarettes daily over the past 20 years. She has a history of smoking cocaine for 8 years but stopped 1 year ago. Vital signs are within normal limits. On mental status examination, she is confused and oriented to person and place only. Neurologic examination shows a delayed return to neutral ankle position after triggering the plantar reflex. Physical examination shows irregular, nonrepetitive, and arrhythmic movements of the neck and head. The patient has poor articulation. Which of the following is the most likely diagnosis?
A. Parkinson disease
B. Multiple sclerosis
C. Huntington disease (Correct Answer)
D. Drug-induced chorea
E. Sydenham chorea
Explanation: ***Huntington disease***
- This patient presents with a classic triad of **motor dysfunction (chorea)**, **cognitive decline (dementia)**, and **psychiatric symptoms (irritability, restlessness, hallucinations, depression)**, which is highly characteristic of Huntington disease.
- The **family history of suicide** in her father at a relatively young age (50), along with the patient's early onset of symptoms (42 years old), suggests an autosomal dominant inheritance pattern typical of Huntington disease.
*Parkinson disease*
- Parkinson disease typically presents with **bradykinesia**, **rigidity**, **tremor at rest**, and **postural instability**, which are distinctly different from the choreiform movements described.
- While cognitive and psychiatric symptoms can occur, the prominent **chorea** and early onset of **dementia** are not typical primary features.
*Multiple sclerosis*
- Multiple sclerosis is characterized by **demyelination** in the central nervous system, leading to a variety of neurological symptoms that are often episodic, such as **visual disturbances**, **weakness**, **sensory deficits**, and **ataxia**.
- It does not typically present with the progressive chorea, cognitive decline, and psychiatric symptoms seen in this patient.
*Drug-induced chorea*
- Drug-induced chorea would typically manifest following the initiation or change in dose of certain medications, and usually resolves upon their discontinuation; this patient's chorea has been ongoing for a year without recent drug changes.
- While she has a history of cocaine use, she stopped 1 year ago, and the progressive nature of the symptoms, along with cognitive and psychiatric deterioration, points away from acute drug-induced effects.
*Sydenham chorea*
- Sydenham chorea is associated with **rheumatic fever** and typically presents in childhood or adolescence following a Group A streptococcal infection.
- The patient's age (42 years old) and the absence of other symptoms of rheumatic fever make Sydenham chorea unlikely.
Question 67: A 60-year-old man presents to the emergency department with a rapid change in his behavior. The patient recently returned from a vacation in rural Mexico and recovered from several episodes of bloody diarrhea. He has had a notable and rapid decline in his memory which started this morning. His personality has also changed, has not been sleeping, and seems generally apathetic. Brief and involuntary muscle twitches have been noted as well. The patient has a past medical history of hypertension and diabetes. His temperature is 99.8°F (37.7°C), blood pressure is 152/98 mmHg, pulse is 97/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam is notable for a confused and apathetic man who is not compliant with the neurological exam. The patient is admitted to the ICU; however, during his hospital course, the patient ultimately dies. Which of the following was most likely to be found in this patient upon initial presentation?
A. Sharp wave complexes on EEG (Correct Answer)
B. Multifocal infarction on MRI
C. Neurofibrillary tangles
D. Tear of a bridging vein
E. Blood in the subarachnoid space
Explanation: ***Sharp wave complexes on EEG***
* The patient's presentation with **rapidly progressive dementia**, personality changes, insomnia, and myoclonus (brief, involuntary muscle twitches) following travel to rural Mexico with bloody diarrhea is highly suggestive of **Creutzfeldt-Jakob disease (CJD)**.
* **Sharp wave complexes on EEG** (also known as periodic sharp wave complexes) are a characteristic finding in CJD, often appearing as highly sensitive and specific indicators of the disease.
* *Multifocal infarction on MRI*
* While **Cerebrovascular accidents** can cause cognitive decline and neurological deficits, the rapid onset and specific constellation of symptoms like myoclonus and personality changes are not typical for multifocal infarction.
* An MRI showing multifocal infarction would indicate multiple areas of **ischemic stroke**, which would present differently from the described progressive neurological decline.
* *Neurofibrillary tangles*
* **Neurofibrillary tangles** are a hallmark pathological feature of **Alzheimer's disease**.
* Alzheimer's disease typically presents with a **slowly progressive dementia** over years, not the rapid decline observed in this patient.
* *Tear of a bridging vein*
* A tear of a bridging vein leads to a **subdural hematoma**, which usually presents with symptoms like headache, confusion, and focal neurological deficits that develop over hours to days.
* The patient's history of bloody diarrhea, rapid cognitive decline, and myoclonus does not fit the typical presentation of a subdural hematoma.
* *Blood in the subarachnoid space*
* **Blood in the subarachnoid space** indicates a **subarachnoid hemorrhage**, which commonly presents as a sudden, severe "thunderclap" headache, often accompanied by neck stiffness, focal neurological deficits, and altered consciousness.
* This presentation does not align with the patient's symptoms of progressive dementia, personality changes, and myoclonus.
Question 68: A 22-year-old man is brought to the physician by his mother because of concerns about his recent behavior. Three months ago, the patient first reported hearing loud voices coming from the ceiling of his room. During this time, he has also become increasingly worried that visitors to the house were placing secret surveillance cameras. Mental status examination shows tangential speech with paranoid thoughts. Treatment for this patient's condition predominantly targets which of the following dopaminergic pathways?
A. Mesocortical pathway
B. Thalamocortical pathway
C. Nigrostriatal pathway
D. Corticostriatal pathway
E. Mesolimbic pathway (Correct Answer)
Explanation: ***Mesolimbic pathway***
- The patient's symptoms of **auditory hallucinations** and **paranoid delusions** are **positive symptoms** of psychosis consistent with **schizophrenia**.
- **Hyperactivity** of the **mesolimbic dopaminergic pathway** is strongly associated with the positive symptoms of schizophrenia, making it the primary target for antipsychotic treatment.
*Mesocortical pathway*
- The **mesocortical pathway** is primarily involved in **cognition, motivation, and executive functions**, originating from the ventral tegmental area and projecting to the prefrontal cortex.
- **Hypoactivity** in this pathway is thought to contribute to the **negative and cognitive symptoms** of schizophrenia, not the positive symptoms described.
*Thalamocortical pathway*
- The **thalamocortical pathway** connects the **thalamus to the cerebral cortex** and is crucial for sensory processing, arousal, and consciousness.
- While involved in neural circuits, it is not considered a primary dopaminergic pathway targeted for the treatment of positive psychotic symptoms.
*Nigrostriatal pathway*
- The **nigrostriatal pathway** projects from the **substantia nigra to the striatum** and is primarily involved in **motor control**.
- Blocking dopamine receptors in this pathway by antipsychotic medications can cause **extrapyramidal symptoms (EPS)**, but it is not the main pathway responsible for positive psychotic symptoms or their treatment.
*Corticostriatal pathway*
- The **corticostriatal pathway** is **predominantly a glutamatergic pathway** connecting the **cerebral cortex to the striatum**, playing a role in motor control and habit formation.
- This is not a primary dopaminergic pathway and is not directly implicated in the positive symptoms of schizophrenia or their pharmacological treatment.
Question 69: A 34-year-old man presents to the behavioral health clinic for an evaluation after seeing animal-shaped clouds in the form of dogs, cats, and monkeys. The patient says that these symptoms have been present for more than 2 weeks. Past medical history is significant for simple partial seizures for which he takes valproate, but he has not had his medication adjusted in several years. His vital signs include: blood pressure of 124/76 mm Hg, heart rate of 98/min, respiratory rate of 12/min, and temperature of 37.1°C (98.8°F). On physical examination, the patient is alert and oriented to person, time, and place. Affect is not constricted or flat. Speech is of rapid rate and high volume. Pupils are equal and reactive bilaterally. The results of a urine drug screen are as follows:
Alcohol positive
Amphetamine negative
Benzodiazepine negative
Cocaine positive
GHB negative
Ketamine negative
LSD negative
Marijuana negative
Opioids negative
PCP negative
Which of the following is the most likely diagnosis in this patient?
A. Delusion
B. Alcohol withdrawal
C. Visual hallucination
D. Cocaine intoxication
E. Illusion (Correct Answer)
Explanation: ***Illusion***
- The patient is seeing **animal shapes in the clouds**, which is a misinterpretation of a real external stimulus. This is the definition of an **illusion**.
- Unlike hallucinations, illusions involve a distorted perception of an existing object, rather than perceiving something that is not present.
*Delusion*
- A **delusion** is a **fixed, false belief** that is not amenable to change in light of conflicting evidence, and it is not what is being described here.
- The patient is experiencing a perceptual distortion, not a false belief system.
*Alcohol withdrawal*
- While the patient tests positive for alcohol, the symptoms described are **perceptual distortions** (misinterpretation of clouds), not typical signs of alcohol withdrawal which include tremors, seizures, and delirium tremens.
- The timeline of "more than 2 weeks" also makes acute alcohol withdrawal less likely, as withdrawal symptoms typically peak within days.
*Visual hallucination*
- A **hallucination** is a perception in the absence of an external stimulus; the patient would be seeing animals when no clouds (or other visual stimuli) are present.
- The patient is seeing animal shapes *in the clouds*, indicating an existing external stimulus that is being misinterpreted.
*Cocaine intoxication*
- While cocaine intoxication can cause psychiatric symptoms like paranoia and hallucinations, the specific description of **seeing animal shapes in clouds** (misinterpretation of a real stimulus) points more directly to an illusion rather than a primary effect of cocaine use.
- The patient's presentation does not include other common symptoms of acute cocaine intoxication like severe agitation, dilated pupils, or hyperthermia beyond a rapid heart rate.
Question 70: A 58-year-old right-handed man is brought to the emergency department after he was found unconscious in his living room by his wife. She reports that he has never had a similar episode before. The patient has hypertension and consumes multiple alcoholic drinks per day. On arrival, he is confused and oriented only to person. He cannot recall what happened. He has difficulty speaking and his words are slurred. He reports a diffuse headache and muscle pain and appears fatigued. His temperature is 37°C (98.6°F), pulse is 85/min, respirations are 14/min, and blood pressure is 135/70 mm Hg. Examination shows a 2-cm bruise on his right shoulder. Strength is 5/5 throughout, except for 1/5 in the left arm. The remainder of the physical examination shows no abnormalities. An ECG shows left ventricular hypertrophy. A CT scan of the head without contrast shows no abnormalities. Which of the following is the most likely underlying cause of this patient's symptoms?
A. Syncope
B. Seizure (Correct Answer)
C. Transient ischemic attack
D. Stroke
E. Migraine
Explanation: ***Seizure***
- The patient's **postictal confusion**, **slurred speech**, **diffuse headache**, and **muscle pain** following a transient loss of consciousness are highly suggestive of a seizure. The unilateral weakness (**Todd's paralysis**) is also a classic postictal phenomenon.
- The **bruise on his shoulder** could indicate a fall during the event, and his alcohol consumption and hypertension are risk factors for seizures.
*Syncope*
- Syncope is characterized by a **brief loss of consciousness due to global cerebral hypoperfusion**, usually followed by rapid and complete recovery of consciousness and neurological function.
- The patient's **prolonged confusion**, **slurred speech**, and **unilateral weakness** after the event are inconsistent with typical syncope.
*Transient ischemic attack*
- A TIA involves **transient neurological dysfunction caused by focal brain or retinal ischemia**, without acute infarction. Symptoms typically resolve within 24 hours.
- While the **slurred speech** and **unilateral weakness** (left arm 1/5 strength) might mimic TIA symptoms, the preceding **loss of consciousness** and subsequent **prolonged postictal state** are not characteristic of a TIA.
*Stroke*
- A stroke involves **brain tissue damage due to ischemia or hemorrhage**, leading to persistent neurological deficits.
- Although he presents with **unilateral weakness** and **slurred speech**, the **head CT without contrast** showed **no abnormalities**, ruling out acute ischemic stroke within the typical detection window for initial CT (within a few hours) and hemorrhagic stroke, and the preceding **loss of consciousness** and **postictal symptoms** point away from a primary stroke.
*Migraine*
- Migraine is a **primary headache disorder** often accompanied by neurological symptoms (aura) but typically does not involve a complete **loss of consciousness**.
- While he has a **diffuse headache**, the **loss of consciousness**, **unilateral weakness**, and **postictal confusion** are inconsistent with migraine.
