A 27-year-old woman comes to the physician because of a 3-day history of a sore throat and fever. Her temperature is 38.5°C (101.3°F). Examination shows edematous oropharyngeal mucosa and enlarged tonsils with purulent exudate. There is tender cervical lymphadenopathy. If left untreated, which of the following conditions is most likely to occur in this patient?
Q1162
A 54-year-old man is brought to the physician by his wife because of progressive difficulty walking during the past 3 months. He has not been able to walk without assistance for the past month and has started to use a wheelchair. He also reports having urinary incontinence for 1 year. His wife says that he has begun to slur his words and has become very difficult to understand. His temperature is 37.0°C (98.6°F), pulse is 70/min, and respirations are 16/min. His blood pressure is 130/80mm Hg while sitting and 110/65mm Hg when standing. He is oriented to person and place but not to time. Neurological examination shows a mild tremor in his right hand and rigidity in his upper and lower extremities. He is unable to perform repetitive rotary forearm movements. Which of the following is the most likely diagnosis?
Q1163
A 50-year-old man is brought to the emergency department by his wife because of lethargy and confusion for the past 24 hours. He has also had a productive cough for the past year and has had a 10-kg (22-lb) weight loss over the past 6 months. He has a history of multiple sclerosis and has not had an acute exacerbation in over 10 years. For the past 30 years, he has smoked 2 packs of cigarettes daily. He drinks 2 beers every day after work. His temperature is 37.0°C (98.6°F), pulse is 90/min, blood pressure is 130/90 mm Hg, and respirations are 22/min. On examination, the patient appears lethargic and cannot state his name or his location. Physical examination reveals scattered wheezing bilaterally. Deep tendon reflexes cannot be elicited. Laboratory studies show:
Serum
Na+ 115 mEq/L
K+ 4.5 mEq/L
HCO3- 22 mEq/L
Glucose 70 mg/dL
Blood urea nitrogen 8 mg/dL
Urine osmolality 450 mOsmol/kg H2O
Urine sodium 70 mEq/L
An x-ray of the chest reveals a central lung mass. Which of the following is the next best step in management?
Q1164
A 55-year-old man with no significant medical history returns for follow-up of a fasting blood glucose (FBG) of 110 mg/dL. His mother had a myocardial infarction at age 52. He weighs 90 kg and his body mass index is 35 kg/m2. His repeat FBG is 160 mg/dL and hemoglobin A1c (HbA1c) is 7.0%. He is started on metformin but is lost to follow-up. Two years later, his HbA1c is 7.6% despite maximal metformin usage, so the patient is started on glyburide. Three months later, his HbA1c is 7.3% while on both medications, and subsequently prescribed glargine and aspart. Three months later, he is brought by his wife to the emergency department for evaluation of altered mental status. His electronic medical record notes that he was started on nitrofurantoin recently for a urinary tract infection. He is disoriented to place and time. His temperature is 99°F (37.2°C), blood pressure is 90/60 mmHg, pulse is 130/min, respirations are 26/min. His basic metabolic panel is shown below:
Serum:
Na+: 119 mEq/L
Cl-: 90 mEq/L
K+: 4.2 mEq/L
HCO3-: 24 mEq/L
BUN: 25 mg/dL
Glucose: 1,400 mg/dL
Creatinine: 1.9 mg/dL
His urine dipstick is negative for ketones. A peripheral intravenous line is established. What is the best initial step in management?
Q1165
A 70-year-old man presented to a medical clinic for a routine follow-up. He has had hypertension for 20 years and is currently on multiple anti-hypertensive medications. The blood pressure is 150/100 mm Hg. The remainder of the examinations were within normal limits. Echocardiography showed some changes in the left ventricle. What is the most likely reason for the change?
Q1166
A 14-year-old male presents to the emergency department with altered mental status. His friends who accompanied him said that he complained of abdominal pain while camping. They denied his consumption of anything unusual from the wilderness, or any vomiting or diarrhea. His temperature is 100.5°F (38.1°C), blood pressure is 95/55 mmHg, pulse is 130/min, and respirations are 30/min. His pupils are equal and reactive to light bilaterally. The remainder of the physical exam is unremarkable. His basic metabolic panel is displayed below:
Serum:
Na+: 116 mEq/L
Cl-: 70 mEq/L
K+: 4.0 mEq/L
HCO3-: 2 mEq/L
BUN: 50 mg/dL
Glucose: 1010 mg/dL
Creatinine: 1.2 mg/dL
While the remainder of his labs are pending, the patient becomes bradypneic and is intubated. His ventilator is adjusted to volume control assist-control with a respiratory rate (RR) of 14/min, tidal volume (Vt) of 350 mL, positive end-expiratory pressure (PEEP) of 5 cm H2O, and fractional inspired oxygen (FiO2) of 40%. His height is 5 feet 5 inches. Intravenous fluids and additional medical therapy are administered. An arterial blood gas obtained after 30 minutes on these settings shows the following:
pH: 7.05
pCO2 :40 mmHg
pO2: 150 mmHg
SaO2: 98%
What is the best next step in management?
Q1167
A 65-year-old man presents to the emergency department for sudden weakness. The patient states that he was at home enjoying his morning coffee when his symptoms began. He says that his left arm suddenly felt very odd and weak thus prompting him to come to the ED. The patient has a past medical history of diabetes, COPD, hypertension, anxiety, alcohol abuse, and PTSD. He recently fell off a horse while horseback riding but claims to not have experienced any significant injuries. He typically drinks 5-7 drinks per day and his last drink was yesterday afternoon. His current medications include insulin, metformin, atorvastatin, lisinopril, albuterol, and fluoxetine. His temperature is 99.5°F (37.5°C), blood pressure is 177/118 mmHg, pulse is 120/min, respirations are 18/min, and oxygen saturation is 93% on room air. On physical exam, you note an elderly man who is mildly confused. Cardiopulmonary exam demonstrates bilateral expiratory wheezes and a systolic murmur along the right upper sternal border that radiates to the carotids. Neurological exam reveals cranial nerves II-XII as grossly intact with finger-nose exam mildly abnormal on the left and heel-shin exam within normal limits. The patient has 5/5 strength in his right arm and 3/5 strength in his left arm. The patient struggles to manipulate objects such as a pen with his left hand. The patient is given a dose of diazepam and started on IV fluids. Which of the following is the most likely diagnosis in this patient?
Q1168
A 40-year-old woman with a past medical history significant for pernicious anemia and vitiligo presents to the physician with the chief complaints of heat intolerance and frequent palpitations. The patient does not take birth control and her urine pregnancy test is negative today. Physical exam reveals a patient that is hyper-reflexive with a non-tender symmetrically enlarged thyroid gland. You order thyroid function tests for workup. What thyroid function values are most expected?
Q1169
A 25-year-old man is brought to the physician because of fatigue, lethargy, and lower leg swelling for 2 weeks. He also noticed that his urine appeared darker than usual and for the last 2 days he has passed only small amounts of urine. His temperature is 37.5°C (98.6°F), pulse is 88/min, respirations are 15/min, and blood pressure is 154/98 mm Hg. Examination shows 2+ pretibial edema bilaterally. Laboratory studies show:
Hemoglobin 10.9 g/dL
Leukocyte count 8200/mm3
Platelet count 220,000/mm3
Serum
Na+ 137 mEq/L
Cl- 102 mEq/L
K+ 4.8 mEq/L
HCO3- 22 mEq/L
Glucose 85 mg/dL
Urea nitrogen 34 mg/dL
Creatinine 1.4 mg/dL
Urine
Blood 2+
Protein 3+
Glucose negative
RBC 10–12/HPF with dysmorphic features
RBC casts numerous
Renal biopsy specimen shows a crescent formation in the glomeruli with extracapillary cell proliferation. Which of the following is the most appropriate next step in management?
Q1170
A 58-year-old woman is brought to the emergency department for shortness of breath and chest pain. Pulmonary angiography shows a large saddle embolus in the pulmonary arteries. Emergency drug therapy is administered and she is admitted to the hospital for observation. A follow-up CT scan of the chest shortly after admission shows that the thrombus has disappeared. Five hours later, the patient is found to be lethargic with slurred speech. Physical examination shows decreased consciousness, dysarthria, and optic disc swelling bilaterally. Which of the following is the most likely cause of her neurological symptoms?
Cardiology US Medical PG Practice Questions and MCQs
Question 1161: A 27-year-old woman comes to the physician because of a 3-day history of a sore throat and fever. Her temperature is 38.5°C (101.3°F). Examination shows edematous oropharyngeal mucosa and enlarged tonsils with purulent exudate. There is tender cervical lymphadenopathy. If left untreated, which of the following conditions is most likely to occur in this patient?
A. Rheumatic fever (Correct Answer)
B. Rheumatoid arthritis
C. Erythema multiforme
D. Toxic shock syndrome
E. Post-streptococcal glomerulonephritis
Explanation: ***Rheumatic fever***
- The patient presents with classic symptoms of **streptococcal pharyngitis** (sore throat, fever, tonsillar exudate, tender cervical lymphadenopathy), which, if left untreated, is a major risk factor for developing **acute rheumatic fever**.
- **Acute rheumatic fever** is a serious inflammatory disease that can affect the **heart valves**, joints, brain, and skin, occurring in approximately **3% of untreated cases** of Group A Streptococcal pharyngitis.
*Rheumatoid arthritis*
- This is a **chronic autoimmune inflammatory disease** primarily affecting the synovial joints, not typically associated with an acute streptococcal infection.
- It involves a different pathophysiological mechanism and is not a direct complication of untreated streptococcal pharyngitis.
*Erythema multiforme*
- This is an **acute, self-limiting skin condition** often triggered by infections (e.g., Herpes simplex virus) or medications, resulting in target lesions.
- While infections can cause it, **streptococcal pharyngitis** is not a common or direct cause, and it's not a systemic complication similar to rheumatic fever.
*Toxic shock syndrome*
- This is a **rapidly progressing infectious disease** characterized by fever, rash, hypotension, and multi-organ failure, most often caused by toxins produced by *Staphylococcus aureus* or *Streptococcus pyogenes*.
- While *Streptococcus pyogenes* (Group A Strep) can cause it, toxic shock syndrome is an **acute complication** rather than a late sequela of untreated infection, making **rheumatic fever** the more characteristic delayed complication.
*Post-streptococcal glomerulonephritis*
- While this is another serious immune-mediated complication of **streptococcal infections**, it **more commonly follows skin infections (impetigo)** than pharyngitis.
- **Rheumatic fever** is the most characteristic and clinically significant late complication of untreated streptococcal **pharyngitis** specifically, with greater emphasis in clinical practice due to its potential for permanent cardiac valve damage.
Question 1162: A 54-year-old man is brought to the physician by his wife because of progressive difficulty walking during the past 3 months. He has not been able to walk without assistance for the past month and has started to use a wheelchair. He also reports having urinary incontinence for 1 year. His wife says that he has begun to slur his words and has become very difficult to understand. His temperature is 37.0°C (98.6°F), pulse is 70/min, and respirations are 16/min. His blood pressure is 130/80mm Hg while sitting and 110/65mm Hg when standing. He is oriented to person and place but not to time. Neurological examination shows a mild tremor in his right hand and rigidity in his upper and lower extremities. He is unable to perform repetitive rotary forearm movements. Which of the following is the most likely diagnosis?
A. Parkinson disease
B. Corticobasal degeneration
C. Friedreich ataxia
D. Normal pressure hydrocephalus
E. Multiple system atrophy (Correct Answer)
Explanation: ***Multiple system atrophy***
- This patient presents with the classic triad of **parkinsonism** (rigidity, tremor), **cerebellar dysfunction** (ataxia, slurred speech, inability to perform repetitive rotary forearm movements indicating dysdiadochokinesia), and prominent **autonomic dysfunction** (urinary incontinence, orthostatic hypotension).
- The rapid progression of symptoms within a few months, including gait instability requiring a wheelchair and severe dysarthria, also points toward an aggressive neurodegenerative disorder like MSA rather than a slower progressing one.
*Parkinson disease*
- While patients with Parkinson disease can present with **parkinsonism** (tremor, rigidity), they typically do not exhibit early and severe **autonomic dysfunction** (like orthostatic hypotension and urinary incontinence) or prominent **cerebellar signs** (ataxia, severe dysarthria, dysdiadochokinesia) at this early stage.
- The progression in Parkinson disease is usually much slower, and requiring a wheelchair within months is atypical.
*Corticobasal degeneration*
- This condition is characterized by marked **asymmetry** of motor symptoms, often with **apraxia**, **alien limb phenomenon**, and cortical sensory deficits, which are not described here.
- While it can cause rigidity and gait disturbance, the significant autonomic dysfunction and cerebellar signs are not typical features.
*Friedreich ataxia*
- This is an inherited neurodegenerative disease that primarily affects the **spinal cord and cerebellum**, leading to **ataxia**, dysarthria, and pyramidal signs.
- However, Friedreich ataxia typically presents in childhood or adolescence, and while it causes ataxia and dysarthria, prominent parkinsonism and severe autonomic dysfunction are not characteristic.
*Normal pressure hydrocephalus*
- This condition is characterized by a triad of **gait disturbance**, **urinary incontinence**, and **dementia**. While these are present, the patient also exhibits clear signs of **parkinsonism** (tremor, rigidity) and **cerebellar dysfunction** (dysarthria, dysdiadochokinesia) that are not features of NPH.
- The orthostatic hypotension is also not a typical finding in NPH.
Question 1163: A 50-year-old man is brought to the emergency department by his wife because of lethargy and confusion for the past 24 hours. He has also had a productive cough for the past year and has had a 10-kg (22-lb) weight loss over the past 6 months. He has a history of multiple sclerosis and has not had an acute exacerbation in over 10 years. For the past 30 years, he has smoked 2 packs of cigarettes daily. He drinks 2 beers every day after work. His temperature is 37.0°C (98.6°F), pulse is 90/min, blood pressure is 130/90 mm Hg, and respirations are 22/min. On examination, the patient appears lethargic and cannot state his name or his location. Physical examination reveals scattered wheezing bilaterally. Deep tendon reflexes cannot be elicited. Laboratory studies show:
Serum
Na+ 115 mEq/L
K+ 4.5 mEq/L
HCO3- 22 mEq/L
Glucose 70 mg/dL
Blood urea nitrogen 8 mg/dL
Urine osmolality 450 mOsmol/kg H2O
Urine sodium 70 mEq/L
An x-ray of the chest reveals a central lung mass. Which of the following is the next best step in management?
A. Order CT scan of the chest
B. Administer hypertonic saline (Correct Answer)
C. Administer conivaptan
D. Administer demeclocycline
E. Administer furosemide
Explanation: **Administer hypertonic saline**
- The patient presents with **severe symptomatic hyponatremia** (Na+ 115 mEq/L) accompanied by neurological symptoms like lethargy and confusion, which necessitates urgent correction to prevent cerebral edema and herniation.
- The constellation of a central lung mass, chronic cough, weight loss, and inappropriate ADH secretion (evidenced by concentrated urine with high urine sodium despite hyponatremia) is highly suggestive of **Small Cell Lung Cancer (SCLC)** causing **SIADH**. Rapid correction with hypertonic saline is indicated for severe symptomatic hyponatremia, especially when likely due to SIADH.
*Order CT scan of the chest*
- While a CT scan of the chest is crucial for further investigating the suspected lung mass, addressing the **life-threatening symptomatic hyponatremia** takes immediate precedence over diagnostic imaging.
- The CT scan should be performed after initial stabilization to evaluate the extent of the suspected lung cancer and guide definitive treatment for the underlying cause of SIADH.
*Administer conivaptan*
- Conivaptan is a **vasopressin receptor antagonist** used to treat hyponatremia, particularly in cases of SIADH or heart failure.
- However, for **severe symptomatic hyponatremia**, particularly with neurological compromise, conivaptan's onset of action may be too slow, and initial management typically involves **hypertonic saline** for rapid correction.
*Administer demeclocycline*
- Demeclocycline is an **antibiotic** that can inhibit ADH action in the renal tubules, making it useful for chronic mild-to-moderate SIADH, particularly for long-term management.
- It is **not suitable for acute, severe symptomatic hyponatremia** requiring rapid correction, as its effects are not immediate.
*Administer furosemide*
- Furosemide is a **loop diuretic** that can be used in SIADH, often in conjunction with hypertonic saline, to induce a water diuresis and prevent volume overload during hypertonic saline administration, especially in patients who are euvolemic or mildly hypervolemic.
- However, administering furosemide alone would worsen volume depletion if present, and it does not directly address the urgent need for sodium replacement in **severe symptomatic hyponatremia**.
Question 1164: A 55-year-old man with no significant medical history returns for follow-up of a fasting blood glucose (FBG) of 110 mg/dL. His mother had a myocardial infarction at age 52. He weighs 90 kg and his body mass index is 35 kg/m2. His repeat FBG is 160 mg/dL and hemoglobin A1c (HbA1c) is 7.0%. He is started on metformin but is lost to follow-up. Two years later, his HbA1c is 7.6% despite maximal metformin usage, so the patient is started on glyburide. Three months later, his HbA1c is 7.3% while on both medications, and subsequently prescribed glargine and aspart. Three months later, he is brought by his wife to the emergency department for evaluation of altered mental status. His electronic medical record notes that he was started on nitrofurantoin recently for a urinary tract infection. He is disoriented to place and time. His temperature is 99°F (37.2°C), blood pressure is 90/60 mmHg, pulse is 130/min, respirations are 26/min. His basic metabolic panel is shown below:
Serum:
Na+: 119 mEq/L
Cl-: 90 mEq/L
K+: 4.2 mEq/L
HCO3-: 24 mEq/L
BUN: 25 mg/dL
Glucose: 1,400 mg/dL
Creatinine: 1.9 mg/dL
His urine dipstick is negative for ketones. A peripheral intravenous line is established. What is the best initial step in management?
A. Glargine insulin
B. 3% hypertonic saline
C. Regular insulin
D. Regular insulin and potassium
E. Lactated ringer's solution (Correct Answer)
Explanation: ***Lactated ringer's solution***
* The patient presents with **hyperglycemic hyperosmolar state (HHS)**, characterized by severe hyperglycemia (glucose 1400 mg/dL), altered mental status, and severe dehydration (hypotension, tachycardia). Initial management prioritizes **aggressive intravenous fluid resuscitation** to correct dehydration and lower osmolality.
* **Lactated Ringer's solution** or **0.9% normal saline** are appropriate initial fluids to restore intravascular volume and improve renal perfusion, preparing the patient for insulin therapy.
*Glargine insulin*
* While insulin is essential for treating HHS, **glargine is a long-acting insulin** and not appropriate for the immediate, acute management of severe hyperglycemia and dehydration in HHS.
* **Rapid-acting or regular insulin** is needed, but only after initial fluid resuscitation has begun and the patient's fluid status is stabilized.
*3% hypertonic saline*
* **Hypotonic hyponatremia** (Na+ 119 mEq/L) despite severe hyperglycemia is likely **pseudohyponatremia** due to the osmotic effect of very high glucose. The corrected sodium should be calculated.
* **3% hypertonic saline** is used for severe, symptomatic hyponatremia, especially when it is true hyponatremia causing cerebral edema, which is not the primary immediate concern here; the immediate priority is fluid repletion for dehydration.
*Regular insulin*
* **Regular insulin** is the correct type of insulin for HHS management, but it should generally be initiated **after volume resuscitation** has begun to avoid precipitating rapid osmotic shifts and hypokalemia.
* Administering insulin first without adequate fluids can worsen dehydration and electrolyte imbalances, particularly **hypokalemia** as insulin drives potassium into cells.
*Regular insulin and potassium*
* While **regular insulin** is eventually needed and **potassium** may be required later, initiating both simultaneously as the *best initial step* is incorrect.
* The immediate and most critical step is **fluid resuscitation** to address profound dehydration and hypovolemic shock. Potassium levels need to be monitored closely during insulin therapy, but in this case, initial potassium is normal (4.2 mEq/L).
Question 1165: A 70-year-old man presented to a medical clinic for a routine follow-up. He has had hypertension for 20 years and is currently on multiple anti-hypertensive medications. The blood pressure is 150/100 mm Hg. The remainder of the examinations were within normal limits. Echocardiography showed some changes in the left ventricle. What is the most likely reason for the change?
A. Disordered growth of the cardiac cells
B. Increase in number of normal cardiac cells
C. Replacement of cardiac cells into stronger red fiber skeletal cells
D. Decrease in cardiac cell size
E. Increase in cardiac cell size (Correct Answer)
Explanation: ***Increase in cardiac cell size***
- Chronic **hypertension** increases the afterload on the left ventricle, causing the cardiac muscle cells (myocytes) to **hypertrophy** (increase in size) to generate greater force to eject blood.
- This adaptive change is a compensatory mechanism to maintain cardiac output against increased systemic vascular resistance.
*Disordered growth of the cardiac cells*
- This description typically refers to **dysplasia**, which involves abnormal cell growth and organization, often raising suspicion for pre-cancerous conditions.
- Cardiac muscle cells, being terminally differentiated, do not commonly undergo dysplastic changes in response to hypertension.
*Increase in number of normal cardiac cells*
- An increase in the number of cells is known as **hyperplasia**, a process that occurs in tissues with high regenerative capacity.
- Mature **cardiac myocytes** have very limited proliferative capacity, so an increase in their number is not the primary mechanism of ventricular adaptation to hypertension.
*Replacement of cardiac cells into stronger red fiber skeletal cells*
- This scenario describes **metaplasia**, where one differentiated cell type is replaced by another.
- Such a transformation from cardiac muscle to skeletal muscle cells does not occur in response to hypertension and is biologically impossible within the heart.
*Decrease in cardiac cell size*
- A decrease in cell size, or **atrophy**, occurs due to decreased workload, nutrition, or hormonal stimulation.
- In hypertension, the workload on the heart is significantly increased, leading to hypertrophy rather than atrophy.
Question 1166: A 14-year-old male presents to the emergency department with altered mental status. His friends who accompanied him said that he complained of abdominal pain while camping. They denied his consumption of anything unusual from the wilderness, or any vomiting or diarrhea. His temperature is 100.5°F (38.1°C), blood pressure is 95/55 mmHg, pulse is 130/min, and respirations are 30/min. His pupils are equal and reactive to light bilaterally. The remainder of the physical exam is unremarkable. His basic metabolic panel is displayed below:
Serum:
Na+: 116 mEq/L
Cl-: 70 mEq/L
K+: 4.0 mEq/L
HCO3-: 2 mEq/L
BUN: 50 mg/dL
Glucose: 1010 mg/dL
Creatinine: 1.2 mg/dL
While the remainder of his labs are pending, the patient becomes bradypneic and is intubated. His ventilator is adjusted to volume control assist-control with a respiratory rate (RR) of 14/min, tidal volume (Vt) of 350 mL, positive end-expiratory pressure (PEEP) of 5 cm H2O, and fractional inspired oxygen (FiO2) of 40%. His height is 5 feet 5 inches. Intravenous fluids and additional medical therapy are administered. An arterial blood gas obtained after 30 minutes on these settings shows the following:
pH: 7.05
pCO2 :40 mmHg
pO2: 150 mmHg
SaO2: 98%
What is the best next step in management?
A. Increase respiratory rate
B. Increase respiratory rate and tidal volume (Correct Answer)
C. Increase tidal volume
D. Increase tidal volume and positive end-expiratory pressure
E. Increase positive end-expiratory pressure
Explanation: ***Increase respiratory rate and tidal volume***
- The patient presents with **severe metabolic acidosis** (pH 7.05, HCO3- 2 mEq/L) due to likely **diabetic ketoacidosis** given the hyperglycemia and altered mental status.
- To compensate for metabolic acidosis, the body attempts to lower pCO2 through **hyperventilation**; therefore, increasing both the **respiratory rate** and **tidal volume** will increase minute ventilation and help "blow off" CO2, thus improving the pH.
*Increase respiratory rate*
- While increasing the respiratory rate will help decrease pCO2 and improve pH, it may not be sufficient on its own to correct the severe acidosis.
- **Tidal volume** also plays a crucial role in minute ventilation and CO2 elimination; addressing both components is more effective.
*Increase tidal volume*
- Increasing tidal volume alone will also increase minute ventilation and help reduce pCO2.
- However, combining it with an increased respiratory rate is more effective for severe acidosis, as both parameters contribute to **CO2 clearance**.
*Increase tidal volume and positive end-expiratory pressure*
- Increasing tidal volume helps reduce pCO2, but increasing PEEP primarily improves **oxygenation** by preventing alveolar collapse and increasing functional residual capacity.
- The patient's pO2 is already high (150 mmHg) with 98% SaO2, so **oxygenation is not the primary concern**; the focus should be on correcting the acidosis by reducing pCO2.
*Increase positive end-expiratory pressure*
- As mentioned, PEEP is primarily used to improve **oxygenation** and manage conditions like acute respiratory distress syndrome (ARDS), which is not the immediate problem here.
- The patient's **pO2 is adequate**, and PEEP will not directly address the **severe metabolic acidosis** or aid significantly in CO2 removal.
Question 1167: A 65-year-old man presents to the emergency department for sudden weakness. The patient states that he was at home enjoying his morning coffee when his symptoms began. He says that his left arm suddenly felt very odd and weak thus prompting him to come to the ED. The patient has a past medical history of diabetes, COPD, hypertension, anxiety, alcohol abuse, and PTSD. He recently fell off a horse while horseback riding but claims to not have experienced any significant injuries. He typically drinks 5-7 drinks per day and his last drink was yesterday afternoon. His current medications include insulin, metformin, atorvastatin, lisinopril, albuterol, and fluoxetine. His temperature is 99.5°F (37.5°C), blood pressure is 177/118 mmHg, pulse is 120/min, respirations are 18/min, and oxygen saturation is 93% on room air. On physical exam, you note an elderly man who is mildly confused. Cardiopulmonary exam demonstrates bilateral expiratory wheezes and a systolic murmur along the right upper sternal border that radiates to the carotids. Neurological exam reveals cranial nerves II-XII as grossly intact with finger-nose exam mildly abnormal on the left and heel-shin exam within normal limits. The patient has 5/5 strength in his right arm and 3/5 strength in his left arm. The patient struggles to manipulate objects such as a pen with his left hand. The patient is given a dose of diazepam and started on IV fluids. Which of the following is the most likely diagnosis in this patient?
A. Bridging vein tear
B. Cerebellar bleeding
C. Berry aneurysm rupture
D. Hypertensive encephalopathy
E. Lipohyalinosis (Correct Answer)
Explanation: ***Lipohyalinosis***
- This patient's history of **hypertension** and **diabetes** are major risk factors for **lipohyalinosis**, which leads to **lacunar infarcts** and presents with sudden onset **pure motor hemiparesis**, as seen with the left arm weakness.
- The elevated blood pressure of 177/118 mmHg further supports a diagnosis involving **cerebral small vessel disease** secondary to chronic hypertension.
*Bridging vein tear*
- A bridging vein tear would typically lead to a **subdural hematoma**, characterized by a **gradual onset of symptoms** like headache, confusion, and neurological deficits, often following trauma, which is inconsistent with the sudden onset in this case.
- While the patient recently fell off a horse, his symptoms are acute and focal, not typical of the delayed presentation often seen with subdural hematomas.
*Cerebellar bleeding*
- **Cerebellar bleeding** usually presents with symptoms such as **ataxia**, **nystagmus**, vertigo, and vomiting, along with potential truncal instability, which are not the primary symptoms observed here.
- While the patient has some mild abnormality on the finger-nose test, the predominant symptom is **pure motor weakness** of the left arm, making a cerebellar bleed less likely.
*Berry aneurysm rupture*
- A **berry aneurysm rupture** typically causes a **sudden, severe headache** (thunderclap headache), neck stiffness, photophobia, and altered mental status due to subarachnoid hemorrhage, which are not reported by the patient.
- The patient's primary complaint is **focal motor weakness** and mild confusion, not the classic diffuse hemorrhagic symptoms of aneurysm rupture.
*Hypertensive encephalopathy*
- **Hypertensive encephalopathy** presents with a more generalized and rapidly progressive decline in neurological function, including severe headache, altered mental status, seizures, and visual disturbances, usually with **diastolic blood pressure >120 mmHg**.
- While the patient's blood pressure is high, the presentation of **focal motor deficit without severe headache** or global neurological decline makes this less likely than a lacunar stroke due to lipohyalinosis.
Question 1168: A 40-year-old woman with a past medical history significant for pernicious anemia and vitiligo presents to the physician with the chief complaints of heat intolerance and frequent palpitations. The patient does not take birth control and her urine pregnancy test is negative today. Physical exam reveals a patient that is hyper-reflexive with a non-tender symmetrically enlarged thyroid gland. You order thyroid function tests for workup. What thyroid function values are most expected?
A. T4 decreased, free T4 decreased, T3 decreased, TSH decreased
B. T4 elevated, free T4 normal, T3 elevated, thyroid stimulating hormone (TSH) normal
C. T4 elevated, free T4 elevated, T3 elevated, TSH elevated
D. T4 normal, free T4 normal, T3 normal, TSH elevated
E. T4 elevated, free T4 elevated, T3 elevated, TSH decreased (Correct Answer)
Explanation: ***T4 elevated, free T4 elevated, T3 elevated, TSH decreased***
- The patient's symptoms (heat intolerance, palpitations, hyper-reflexia) and signs (non-tender symmetrically enlarged thyroid gland) are classic for **hyperthyroidism**, specifically **Graves' disease** given the autoimmune comorbidities (pernicious anemia, vitiligo).
- In primary hyperthyroidism, the thyroid gland overproduces T3 and T4, leading to **elevated T3 and T4 levels**, which in turn suppress TSH secretion, resulting in a **decreased TSH**.
*T4 decreased, free T4 decreased, T3 decreased, TSH decreased*
- This pattern (low T3, T4, and TSH) is indicative of **central hypothyroidism** (secondary or tertiary hypothyroidism), where the pituitary or hypothalamus is unable to produce sufficient TSH.
- This contrasts with the patient's symptoms and signs, which are clearly suggestive of an overactive thyroid gland.
*T4 elevated, free T4 normal, T3 elevated, thyroid stimulating hormone (TSH) normal*
- This combination is not consistent with a typical thyroid disorder scenario. While T4 and T3 could be elevated in hyperthyroidism, a **normal TSH** alongside elevated thyroid hormones is generally anomalous unless there is resistance to thyroid hormones or a TSH-secreting pituitary adenoma.
- The elevated T3 and T4 would typically suppress TSH in primary hyperthyroidism, making a normal TSH unlikely.
*T4 elevated, free T4 elevated, T3 elevated, TSH elevated*
- This pattern (elevated TSH with elevated T3 and T4) is characteristic of **secondary hyperthyroidism**, such as a **TSH-secreting pituitary adenoma**.
- While it represents hyperthyroidism, the patient's presentation with a symmetrically enlarged thyroid and autoimmune history strongly points towards Graves' disease, which is primary hyperthyroidism with suppressed TSH.
*T4 normal, free T4 normal, T3 normal, TSH elevated*
- This profile represents **subclinical hypothyroidism**, where the thyroid hormone levels are within the normal range, but the pituitary is working harder (elevated TSH) to maintain this normal state.
- This contradicts the patient's overt symptoms of hyperthyroidism (heat intolerance, palpitations, hyper-reflexia).
Question 1169: A 25-year-old man is brought to the physician because of fatigue, lethargy, and lower leg swelling for 2 weeks. He also noticed that his urine appeared darker than usual and for the last 2 days he has passed only small amounts of urine. His temperature is 37.5°C (98.6°F), pulse is 88/min, respirations are 15/min, and blood pressure is 154/98 mm Hg. Examination shows 2+ pretibial edema bilaterally. Laboratory studies show:
Hemoglobin 10.9 g/dL
Leukocyte count 8200/mm3
Platelet count 220,000/mm3
Serum
Na+ 137 mEq/L
Cl- 102 mEq/L
K+ 4.8 mEq/L
HCO3- 22 mEq/L
Glucose 85 mg/dL
Urea nitrogen 34 mg/dL
Creatinine 1.4 mg/dL
Urine
Blood 2+
Protein 3+
Glucose negative
RBC 10–12/HPF with dysmorphic features
RBC casts numerous
Renal biopsy specimen shows a crescent formation in the glomeruli with extracapillary cell proliferation. Which of the following is the most appropriate next step in management?
A. Administer methylprednisolone (Correct Answer)
B. Administer lisinopril
C. Administer cyclosporine A
D. Perform hemodialysis
E. Administer rituximab
Explanation: ***Administer methylprednisolone***
- The patient presents with **rapidly progressive glomerulonephritis (RPGN)**, characterized by acute renal failure, nephritic-range proteinuria, dysmorphic red blood cells, RBC casts, and crescent formation on biopsy. **High-dose corticosteroids (e.g., methylprednisolone)** are the first-line treatment to suppress inflammation and preserve renal function in RPGN.
- The presence of **crescent formation** in the glomeruli indicates severe glomerular injury and is a hallmark of RPGN, necessitating aggressive immunosuppressive therapy like corticosteroids.
*Administer lisinopril*
- **Lisinopril**, an **ACE inhibitor**, is primarily used to manage hypertension and reduce proteinuria in chronic kidney disease, but it is not the initial treatment for acute, rapidly progressing glomerulonephritis with active inflammation.
- While the patient has hypertension (154/98 mm Hg), addressing the underlying inflammatory process with immunosuppression takes precedence over symptomatic blood pressure management in this acute setting.
*Administer cyclosporine A*
- **Cyclosporine A** is an immunosuppressant that can be used in certain forms of glomerulonephritis, but it is typically reserved for cases that are **refractory to corticosteroids** or as a second-line agent.
- It's not typically the initial therapy for RPGN due to its potential **nephrotoxicity** and slower onset of action compared to high-dose corticosteroids.
*Perform hemodialysis*
- **Hemodialysis** is indicated for **end-stage renal disease** or severe complications of acute kidney injury, such as refractory anasarca, severe metabolic acidosis, or hyperkalemia.
- While the patient has elevated creatinine and oliguria, his condition is acute and potentially reversible with immunosuppressive therapy. Hemodialysis would be considered if medical management fails or if life-threatening complications develop.
*Administer rituximab*
- **Rituximab**, an anti-CD20 monoclonal antibody, is used in specific types of glomerulonephritis, such as **ANCA-associated vasculitis** or **membranous nephropathy** that is refractory to other treatments.
- It is not the initial treatment for undifferentiated RPGN, especially without specific serologic markers like ANCA being positive or an established diagnosis for which rituximab is the primary agent.
Question 1170: A 58-year-old woman is brought to the emergency department for shortness of breath and chest pain. Pulmonary angiography shows a large saddle embolus in the pulmonary arteries. Emergency drug therapy is administered and she is admitted to the hospital for observation. A follow-up CT scan of the chest shortly after admission shows that the thrombus has disappeared. Five hours later, the patient is found to be lethargic with slurred speech. Physical examination shows decreased consciousness, dysarthria, and optic disc swelling bilaterally. Which of the following is the most likely cause of her neurological symptoms?
A. Acute metabolic encephalopathy
B. Embolic cerebrovascular accident
C. Idiopathic intracranial hypertension
D. Intracerebral hemorrhage (Correct Answer)
E. Drug-induced hypotension
Explanation: ***Intracerebral hemorrhage***
- The patient was treated for a **saddle pulmonary embolism** with drug therapy (likely thrombolytics). This type of therapy carries a significant risk of **intracerebral hemorrhage**, especially in older patients or those with underlying risks. The sudden onset of neurological symptoms, including decreased consciousness, dysarthria, and **bilateral optic disc swelling** (indicating increased intracranial pressure), five hours after receiving thrombolytic therapy, is highly suspicious for a hemorrhagic stroke.
- The rapid dissolution of the pulmonary thrombus followed by new neurological deficits strongly suggests a side effect of aggressive anticoagulation or thrombolysis.
*Acute metabolic encephalopathy*
- While metabolic encephalopathy can cause decreased consciousness and lethargy, it typically does not present with focal neurological signs like **dysarthria** or **optic disc swelling** indicating increased intracranial pressure.
- The rapid onset immediately following thrombolytic treatment for a significant thromboembolic event points away from a primary metabolic cause.
*Embolic cerebrovascular accident*
- An embolic stroke could cause similar neurological symptoms, but the history of massive thrombolysis for a pulmonary embolism makes **hemorrhage** a more immediate concern given the treatment. Additionally, an embolic stroke would not typically cause **bilateral optic disc swelling** so rapidly.
- While theoretically possible if a paradoxical embolism occurred (e.g., via a patent foramen ovale), the administration of powerful anticoagulants/thrombolytics makes hemorrhage the more probable complication.
*Idiopathic intracranial hypertension*
- This condition is characterized by **increased intracranial pressure without an identifiable cause** and primarily affects young, obese women. It typically presents with chronic headaches and visual disturbances, but rarely acute neurological deterioration with decreased consciousness or dysarthria.
- The acute, post-treatment onset of symptoms is inconsistent with the chronic nature of idiopathic intracranial hypertension.
*Drug-induced hypotension*
- Severe hypotension could lead to global cerebral hypoperfusion and altered mental status, but it usually causes more generalized symptoms, and is less likely to produce focal neurological signs like **dysarthria** or **bilateral optic disc swelling** within such a short timeframe as the primary cause.
- While hypotension can be a side effect of some drugs, the specific constellation of symptoms, particularly the optic disc swelling, points more directly towards an acute intracranial event like hemorrhage.
