A 34-year-old woman presents to her primary care provider after intermittently passing bright pink urine over several days. She is concerned this discoloration is due to blood. Her medical history is unremarkable, she denies being sick in the past weeks and has only taken a couple of diclofenac capsules for pelvic pain associated to her menstrual period. She does not drink alcohol or smoke cigarettes. At the doctor’s office, her blood pressure is 150/90 mm Hg, pulse is 80/min, respiratory rate is 18/min, and temperature is 36.5°C (97.7°F). On physical exam, she has 2+ pitting edema up to her knees. A urinalysis is taken which shows red blood cells, red blood cell casts, and acanthocytes. No proteinuria was detected. Her serum creatinine is 2.4 mg/dL, blood urea nitrogen 42 mg/dL, serum potassium 4.8 mEq/L, serum sodium 140 mEq/L, serum chloride 102 mEq/L. Which of the following is the most appropriate next step in the management of this case?
Q632
A 28-year-old man comes to the physician for a follow-up examination after a previous visit showed an elevated serum calcium level. He has a history of bipolar disorder. His mother had a parathyroidectomy in her 30s. The patient does not drink alcohol or smoke. Current medications include lithium and a daily multivitamin. His vital signs are within normal limits. Physical examination shows no abnormalities. Laboratory studies show:
Serum
Sodium 146 mEq/L
Potassium 3.7 mEq/L
Calcium 11.2 mg/dL
Magnesium 2.3 mEq/L
PTH 610 pg/mL
Albumin 4.2 g/dL
24-hour urine
Calcium 23 mg
Which of the following is the most likely cause of this patient’s findings?
Q633
A 53-year-old woman presents to her primary care physician with complaints of pain and swelling in her hands and fingers. She states that she has had these symptoms since she was in her 20s, but they have recently become more severe. She states that her wedding ring no longer fits, due to increased swelling of her fingers. She is a 30-pack-year smoker with a body mass index (BMI) of 31 kg/m2. The vital signs include: blood pressure 122/78 mm Hg, heart rate 72/min, and respiratory rate 15/min. On physical exam, a mild systolic murmur is heard over the apex, and her lungs are clear bilaterally. There is swelling of all the digits bilaterally, and a yellow-white plaque is noted beneath 3 of her nail beds. When asked about the plaques, she states that she was given itraconazole for them about 3 weeks ago; however, the plaques did not resolve. When asked further about joint pain, she notes that she has had shoulder and knee pain for the last several years, although she has not sought medical care for this. Which of the following is the best initial step in this patient’s therapeutic management?
Q634
A 19-year-old male arrives to student health for an annual check up. He is up to date on his infant and childhood vaccinations up to age 10. At age 12, he received a single dose of the tetanus, diphtheria, and acellular pertussis vaccine, and a quadrivalent meningococcal conjugate vaccine. A month ago, he received the influenza vaccine. The patient has no significant medical history. He takes over the counter ibuprofen for occasional headaches. He has a father with hypertension and hyperlipidemia, and his brother has asthma. He is sexually active with his current girlfriend. He denies tobacco use, illicit drug use, and recent or future travel. The patient’s temperature is 98°F (36.7°C), blood pressure is 118/78 mmHg, pulse is 70/min, and respirations are 14/min with an oxygen saturation of 99% O2 on room air. A physical examination is normal. What of the following is the best recommendation for vaccination?
Q635
A 57-year-old man with a history of coronary artery disease has been brought to the emergency department due to the sudden onset of chest pain. He was diagnosed with hypertension 12 years ago and takes enalapril regularly. The patient is hypotensive to 70/42 mm Hg, and on further examination his skin is cold and clammy. He is diagnosed with a life-threatening condition that resulted from inadequate circulation of blood, with decreased cardiac output and high pulmonary capillary wedge pressure. Which of the conditions below can cause the same disorder?
I. Acute myocardial infarction
II. Atrial fibrillation
III. Hemorrhage
IV. Valvular stenosis
V. Pulmonary embolism
VI. Sepsis
Q636
A 55-year-old man presents to the physician for the evaluation of excessive daytime sleepiness over the past six months. Despite sleeping 8–9 hours a night and taking a nap during the day, he feels drowsy and is afraid to drive. His wife complains of loud snoring and gasping during the night. His blood pressure is 155/95 mm Hg. BMI is 37 kg/m2. Oropharyngeal examination shows a small orifice and an enlarged tongue and uvula. The soft palate is low-lying. The examination of the nasal cavity shows no septal deviation or polyps. Examination of the lungs and heart shows no abnormalities. Polysomnography shows an apnea-hypopnea index of 20 episodes/h. The patient is educated about weight loss, exercise, and regular sleep hours and duration. Which of the following is the most appropriate next step in management?
Q637
A 60-year-old man comes to the emergency department because of a 3-day history of fever and shortness of breath. He has a history of COPD treated with inhaled albuterol. His temperature is 39.0°C (102.2°F), pulse is 95/min, respirations are 20/min, and blood pressure is 130/80 mm Hg. Cardiopulmonary examination shows decreased breath sounds and poor air movement over the left lung. A lateral decubitus x-ray of the chest shows a pleural effusion height of 2 cm. Thoracentesis is performed and pleural fluid analysis shows a protein concentration of 4.0 g/dL and LDH of 280 U/L. Which of the following is the most likely underlying cause of this patient's effusion?
Q638
A 59-year-old man is brought to the emergency department by a coworker for right arm weakness and numbness. The symptoms started suddenly 2 hours ago. His coworker also noticed his face appears to droop on the right side and his speech is slurred. He has a history of hypertension, hyperlipidemia, type 2 diabetes, and peripheral arterial disease. He works as a partner at a law firm and has been under more stress than usual lately. His father died of a stroke at age 70. The patient has smoked a pack of cigarettes daily for the last 40 years. He drinks two pints (750 mL) of whiskey each week. He takes aspirin, atorvastatin, lisinopril, and metformin daily. He is 167.6 cm (5 ft 6 in) tall and weighs 104.3 kg (230 lb); BMI is 37 kg/m2. His temperature is 37.1°C (98.8°F), pulse is 92/min, respirations are 15/min, and blood pressure is 143/92 mm Hg. He is fully alert and oriented. Neurological examination shows asymmetry of the face with droop of the lips on the right. There is 3/5 strength in right wrist flexion and extension, and right finger abduction. Sensation to light touch and pinprick is reduced throughout the right arm. Which of the following is the strongest predisposing factor for this patient's condition?
Q639
A 56-year-old woman comes to the physician because of increasing muscle weakness in her shoulders and legs for 1 month. She has difficulties standing up and combing her hair. She also has had a skin rash on her face and hands for the past week. She has hypercholesterolemia treated with simvastatin. She has chronic eczema of her feet that is well-controlled with skin moisturizer and corticosteroid cream. Her mother and sister have thyroid disease. Vital signs are within normal limits. Examination shows facial erythema. A photograph of her hands is shown. Muscle strength is 3/5 in the iliopsoas, hamstring, deltoid, and biceps muscles. Sensation to pinprick, temperature, and vibration is intact. Further evaluation of this patient is most likely to show which of the following?
Q640
A previously healthy 61-year-old man comes to the physician because of a 6-month history of morning headaches. He also has fatigue and trouble concentrating on his daily tasks at work. He sleeps for 8 hours every night; his wife reports that he sometimes stops breathing for a few seconds while sleeping. His pulse is 71/min and blood pressure is 158/96 mm Hg. He is 178 cm (5 ft 10 in) tall and weighs 100 kg (220 lb); BMI is 31.6 kg/m2 . Which of the following is the most likely cause of this patient's hypertension?
Cardiology US Medical PG Practice Questions and MCQs
Question 631: A 34-year-old woman presents to her primary care provider after intermittently passing bright pink urine over several days. She is concerned this discoloration is due to blood. Her medical history is unremarkable, she denies being sick in the past weeks and has only taken a couple of diclofenac capsules for pelvic pain associated to her menstrual period. She does not drink alcohol or smoke cigarettes. At the doctor’s office, her blood pressure is 150/90 mm Hg, pulse is 80/min, respiratory rate is 18/min, and temperature is 36.5°C (97.7°F). On physical exam, she has 2+ pitting edema up to her knees. A urinalysis is taken which shows red blood cells, red blood cell casts, and acanthocytes. No proteinuria was detected. Her serum creatinine is 2.4 mg/dL, blood urea nitrogen 42 mg/dL, serum potassium 4.8 mEq/L, serum sodium 140 mEq/L, serum chloride 102 mEq/L. Which of the following is the most appropriate next step in the management of this case?
A. Discontinuation of NSAID
B. Fomepizole
C. Intravenous fluid therapy and electrolyte correction
D. Noncontrast computed tomography
E. Renal biopsy (Correct Answer)
Explanation: ***Renal biopsy***
- The patient presents with **acute nephritic syndrome**, characterized by **hypertension**, **edema**, and **active urine sediment** (RBCs, RBC casts, acanthocytes) indicating glomerular inflammation, despite no overt proteinuria.
- Given the features of rapid progression (elevated creatinine) and the classic findings of nephritic urine, a **renal biopsy** is crucial for establishing the specific diagnosis (e.g., IgA nephropathy, post-infectious glomerulonephritis, rapidly progressive glomerulonephritis) and guiding appropriate immunosuppressive therapy.
*Discontinuation of NSAID*
- While **NSAIDs** can cause acute kidney injury, the presence of **RBC casts** and **acanthocytes** in the urine strongly points towards a **glomerular pathology**, which is not typically caused solely by NSAID use.
- Although NSAIDs should generally be avoided in kidney injury, simply discontinuing them would not address the underlying glomerular disease.
*Fomepizole*
- **Fomepizole** is an antidote used for **ethylene glycol** or **methanol poisoning**, which cause a severe **metabolic acidosis** and often acute kidney injury with oxalate crystals.
- The patient's presentation does not suggest toxic alcohol ingestion; she has no severe acidosis, and the urine sediment points to intrinsic glomerular disease.
*Intravenous fluid therapy and electrolyte correction*
- While the patient has **elevated creatinine** and potential fluid overload (pitting edema), her electrolytes are currently within normal limits, and the initial management should focus on diagnosing the underlying cause of her nephritic syndrome.
- Aggressive fluid administration might worsen her **hypertension** and **edema** in the setting of acute kidney injury with fluid retention.
*Noncontrast computed tomography*
- A **noncontrast CT** is useful for identifying kidney stones, hydronephrosis, or large renal masses as causes of hematuria but would not provide the specific diagnosis for a **glomerular disease** manifesting with RBC casts and acanthocytes.
- It would not show the microscopic changes crucial for diagnosing glomerulonephritis, making it a less appropriate initial step compared to a renal biopsy in this context.
Question 632: A 28-year-old man comes to the physician for a follow-up examination after a previous visit showed an elevated serum calcium level. He has a history of bipolar disorder. His mother had a parathyroidectomy in her 30s. The patient does not drink alcohol or smoke. Current medications include lithium and a daily multivitamin. His vital signs are within normal limits. Physical examination shows no abnormalities. Laboratory studies show:
Serum
Sodium 146 mEq/L
Potassium 3.7 mEq/L
Calcium 11.2 mg/dL
Magnesium 2.3 mEq/L
PTH 610 pg/mL
Albumin 4.2 g/dL
24-hour urine
Calcium 23 mg
Which of the following is the most likely cause of this patient’s findings?
A. Lithium toxicity
B. Parathyroid adenoma
C. Excess calcium intake
D. Excess vitamin D intake
E. Abnormal calcium sensing receptors (Correct Answer)
Explanation: ***Abnormal calcium sensing receptors***
- The patient's **hypocalciuric hypercalcemia** (high serum calcium, low urine calcium) in the presence of an **elevated PTH** suggests a defect in calcium sensing.
- The family history of parathyroidectomy in the mother is consistent with an inherited condition affecting **calcium-sensing receptors (CaSRs)**, such as **familial hypocalciuric hypercalcemia (FHH)**.
*Lithium toxicity*
- **Lithium** can cause hypercalcemia by increasing the set point for calcium at the parathyroid gland, leading to increased PTH secretion.
- However, lithium typically does not lead to **hypocalciuria** to the extent seen in FHH, as it does not directly affect the kidney's CaSR in the same manner.
*Parathyroid adenoma*
- A **parathyroid adenoma** would cause **primary hyperparathyroidism**, characterized by hypercalcemia and elevated PTH.
- However, primary hyperparathyroidism typically presents with **hypercalciuria** due to the PTH-mediated increase in renal calcium reabsorption being overwhelmed by the increased filtered calcium load, unlike the hypocalciuria seen here.
*Excess calcium intake*
- **Excess calcium intake** could lead to hypercalcemia, but this would typically suppress PTH (unless it's a milk-alkali syndrome variant).
- It would also lead to **hypercalciuria** as the kidneys attempt to excrete the excess calcium, which is not observed here with a suppressed 24-hour urine calcium.
*Excess vitamin D intake*
- **Excess vitamin D intake** causes hypercalcemia by increasing intestinal calcium absorption and bone resorption, and would typically lead to **suppressed PTH** levels.
- It would also typically result in **hypercalciuria** due to the increased filtered calcium load, contrasting with the low urine calcium in this patient.
Question 633: A 53-year-old woman presents to her primary care physician with complaints of pain and swelling in her hands and fingers. She states that she has had these symptoms since she was in her 20s, but they have recently become more severe. She states that her wedding ring no longer fits, due to increased swelling of her fingers. She is a 30-pack-year smoker with a body mass index (BMI) of 31 kg/m2. The vital signs include: blood pressure 122/78 mm Hg, heart rate 72/min, and respiratory rate 15/min. On physical exam, a mild systolic murmur is heard over the apex, and her lungs are clear bilaterally. There is swelling of all the digits bilaterally, and a yellow-white plaque is noted beneath 3 of her nail beds. When asked about the plaques, she states that she was given itraconazole for them about 3 weeks ago; however, the plaques did not resolve. When asked further about joint pain, she notes that she has had shoulder and knee pain for the last several years, although she has not sought medical care for this. Which of the following is the best initial step in this patient’s therapeutic management?
A. Administer methotrexate
B. Administer indomethacin
C. Administer indomethacin and methotrexate (Correct Answer)
D. Administer sulfasalazine
E. Administer indomethacin and sulfasalazine
Explanation: ***Administer indomethacin and methotrexate***
- This patient presents with symptoms highly suggestive of **psoriatic arthritis**, including typical joint pain distribution (hands, fingers, shoulders, knees), **dactylitis** (swelling of all digits causing the wedding ring to no longer fit), and **nail lesions** (yellow-white plaques unresponsive to antifungals).
- Given the patient's severe and chronic symptoms, a **combination of a non-steroidal anti-inflammatory drug (NSAID) like indomethacin for symptomatic relief and a disease-modifying anti-rheumatic drug (DMARD) like methotrexate** is the most appropriate initial therapy to control inflammation and prevent joint damage.
*Administer methotrexate*
- While **methotrexate** is a cornerstone DMARD for psoriatic arthritis, it takes several weeks to exert its full therapeutic effects.
- Administering methotrexate alone would not provide immediate relief for the patient's significant pain and swelling.
*Administer indomethacin*
- **Indomethacin**, an NSAID, would provide symptomatic relief from pain and inflammation.
- However, NSAIDs alone do not modify the disease course or prevent joint damage in psoriatic arthritis; therefore, it is an insufficient long-term monotherapy.
*Administer sulfasalazine*
- **Sulfasalazine** is an alternative DMARD used in psoriatic arthritis, often considered for patients who cannot tolerate methotrexate or for milder forms, especially with peripheral arthritis.
- However, for a patient with severe, chronic, and potentially erosive disease suggested by long-standing symptoms and diffuse dactylitis, **methotrexate is generally preferred due to its stronger efficacy profile** as an initial DMARD for psoriatic arthritis if no contraindications exist.
*Administer indomethacin and sulfasalazine*
- This combination provides short-term symptomatic relief (indomethacin) and long-term disease modification (sulfasalazine).
- While a valid option, **methotrexate is generally considered the first-line DMARD for psoriatic arthritis**, especially in severe cases, due to its greater efficacy in controlling both skin and joint manifestations compared to sulfasalazine.
Question 634: A 19-year-old male arrives to student health for an annual check up. He is up to date on his infant and childhood vaccinations up to age 10. At age 12, he received a single dose of the tetanus, diphtheria, and acellular pertussis vaccine, and a quadrivalent meningococcal conjugate vaccine. A month ago, he received the influenza vaccine. The patient has no significant medical history. He takes over the counter ibuprofen for occasional headaches. He has a father with hypertension and hyperlipidemia, and his brother has asthma. He is sexually active with his current girlfriend. He denies tobacco use, illicit drug use, and recent or future travel. The patient’s temperature is 98°F (36.7°C), blood pressure is 118/78 mmHg, pulse is 70/min, and respirations are 14/min with an oxygen saturation of 99% O2 on room air. A physical examination is normal. What of the following is the best recommendation for vaccination?
A. Human papillomavirus vaccine (Correct Answer)
B. Hepatitis A vaccine
C. Herpes zoster vaccine
D. Pneumococcal vaccine
E. Tetanus and reduced diphtheria toxoid booster
Explanation: ***Human papilloma virus***
- This patient, being 19 years old and **sexually active**, is a prime candidate for the **HPV vaccine** to prevent infections that can lead to various cancers.
- The CDC recommends routine HPV vaccination at age 11-12, but catch-up vaccination is recommended for individuals up to age 26 if not adequately vaccinated previously.
*Hepatitis A vaccine*
- The Hepatitis A vaccine is generally recommended for individuals at **increased risk** of infection, such as travelers to endemic areas, men who have sex with men, or those with chronic liver disease, none of which apply to this patient.
- There is no indication for routine vaccination without specific risk factors in this otherwise healthy young male.
*Herpes zoster vaccine*
- The herpes zoster (shingles) vaccine is recommended for adults **age 50 years and older** to prevent shingles.
- This patient is only 19 years old, making him too young for this vaccine recommendation.
*Pneumococcal vaccine*
- Pneumococcal vaccines (PCV13 and PPSV23) are typically recommended for **young children**, adults **65 years and older**, or individuals with **certain underlying medical conditions** (e.g., chronic heart, lung, or kidney disease, or immunocompromised states).
- This 19-year-old patient has no such risk factors for pneumococcal disease.
*Tetanus and reduced diphtheria toxoid booster*
- The patient received a Tdap vaccine at age 12. A Td booster is recommended **every 10 years** for adults.
- Since it has been only 7 years since his last Tdap vaccine, he is not due for a Td booster at this time.
Question 635: A 57-year-old man with a history of coronary artery disease has been brought to the emergency department due to the sudden onset of chest pain. He was diagnosed with hypertension 12 years ago and takes enalapril regularly. The patient is hypotensive to 70/42 mm Hg, and on further examination his skin is cold and clammy. He is diagnosed with a life-threatening condition that resulted from inadequate circulation of blood, with decreased cardiac output and high pulmonary capillary wedge pressure. Which of the conditions below can cause the same disorder?
I. Acute myocardial infarction
II. Atrial fibrillation
III. Hemorrhage
IV. Valvular stenosis
V. Pulmonary embolism
VI. Sepsis
A. I, II, IV (Correct Answer)
B. I, II, IV, V
C. I, IV, VI
D. I, II, III
E. I, IV, V
Explanation: ***I, II, IV (Acute myocardial infarction, Atrial fibrillation, Valvular stenosis)***
- The patient's presentation with **hypotension**, **cold and clammy skin**, **decreased cardiac output**, and **high pulmonary capillary wedge pressure** is characteristic of **cardiogenic shock**.
- **Acute myocardial infarction** causes cardiogenic shock through direct myocardial damage and pump failure, leading to elevated left ventricular filling pressures and high PCWP.
- **Atrial fibrillation** can cause cardiogenic shock through loss of atrial kick (reducing CO by 20-30%), rapid ventricular rates impairing diastolic filling, and tachycardia-induced cardiomyopathy—all resulting in pump failure with elevated PCWP.
- Severe **valvular stenosis** (aortic or mitral) causes cardiogenic shock by obstructing cardiac output and causing backward transmission of pressure, resulting in elevated PCWP.
*I, II, IV, V*
- This option incorrectly includes **pulmonary embolism** as a cause of cardiogenic shock with **high pulmonary capillary wedge pressure**.
- While pulmonary embolism causes profound hypotension and shock, it produces **obstructive shock** with **low or normal PCWP** due to right ventricular outflow obstruction and right heart failure, not left heart pump failure.
*I, IV, VI*
- This option incorrectly includes **sepsis** and excludes **atrial fibrillation**.
- **Sepsis** causes **distributive shock** characterized by **low systemic vascular resistance** and typically **low or normal PCWP** initially, though late septic cardiomyopathy can occur, it does not present with the classic high PCWP pattern described.
*I, II, III*
- This option incorrectly includes **hemorrhage** as a cause of cardiogenic shock.
- **Hemorrhage** causes **hypovolemic shock** with **low cardiac output** due to reduced preload and **low PCWP**, not the high PCWP characteristic of cardiogenic shock.
*I, IV, V*
- This option incorrectly includes **pulmonary embolism** and excludes **atrial fibrillation**.
- **Pulmonary embolism** causes **obstructive shock** with right ventricular dysfunction and **low or normal PCWP**, not the elevated PCWP seen in cardiogenic shock from left heart pump failure.
Question 636: A 55-year-old man presents to the physician for the evaluation of excessive daytime sleepiness over the past six months. Despite sleeping 8–9 hours a night and taking a nap during the day, he feels drowsy and is afraid to drive. His wife complains of loud snoring and gasping during the night. His blood pressure is 155/95 mm Hg. BMI is 37 kg/m2. Oropharyngeal examination shows a small orifice and an enlarged tongue and uvula. The soft palate is low-lying. The examination of the nasal cavity shows no septal deviation or polyps. Examination of the lungs and heart shows no abnormalities. Polysomnography shows an apnea-hypopnea index of 20 episodes/h. The patient is educated about weight loss, exercise, and regular sleep hours and duration. Which of the following is the most appropriate next step in management?
A. Continuous positive airway pressure (Correct Answer)
B. Upper airway neurostimulation
C. Supplemental oxygen
D. Oral appliances
E. Upper airway surgery
Explanation: ***Continuous positive airway pressure***
- This patient presents with symptoms and polysomnography findings consistent with **moderate to severe obstructive sleep apnea (OSA)** (apnea-hypopnea index of 20 episodes/h). **CPAP is the first-line treatment** for such cases.
- CPAP works by **delivering pressurized air** via a mask, creating a pneumatic splint that prevents the collapse of the upper airway during sleep, thereby reducing apneas and hypopneas.
*Upper airway neurostimulation*
- This therapy involves stimulating the **hypoglossal nerve** to activate upper airway muscles, improving airway patency.
- However, it is generally considered a **second-line treatment** for patients with moderate to severe OSA who **cannot tolerate or fail CPAP therapy**.
*Supplemental oxygen*
- While oxygen therapy can reduce nocturnal desaturation, it **does not address the underlying airway obstruction** that causes apneas and hypopneas.
- It might even **worsen apnea by blunting the ventilatory drive**, making it an inappropriate primary treatment for OSA.
*Oral appliances*
- **Mandibular advancement devices (MADs)** can be effective for **mild to moderate OSA**, or for patients with severe OSA who cannot tolerate CPAP.
- They work by repositioning the jaw and tongue forward to enlarge the pharyngeal space, but CPAP is generally more effective for the severity described.
*Upper airway surgery*
- Various surgical procedures, such as **uvulopalatopharyngoplasty (UPPP)**, aim to remove excess tissue in the pharynx to enlarge the airway.
- Surgery is typically reserved for patients who **fail or cannot tolerate CPAP and oral appliances** and are carefully selected based on anatomical considerations.
Question 637: A 60-year-old man comes to the emergency department because of a 3-day history of fever and shortness of breath. He has a history of COPD treated with inhaled albuterol. His temperature is 39.0°C (102.2°F), pulse is 95/min, respirations are 20/min, and blood pressure is 130/80 mm Hg. Cardiopulmonary examination shows decreased breath sounds and poor air movement over the left lung. A lateral decubitus x-ray of the chest shows a pleural effusion height of 2 cm. Thoracentesis is performed and pleural fluid analysis shows a protein concentration of 4.0 g/dL and LDH of 280 U/L. Which of the following is the most likely underlying cause of this patient's effusion?
A. Decreased intrapleural pressure
B. Increased pulmonary capillary permeability (Correct Answer)
C. Decreased plasma oncotic pressure
D. Increased pulmonary capillary pressure
E. Impaired lymphatic flow
Explanation: ***Increased pulmonary capillary permeability***
- This patient presents with **fever**, **shortness of breath**, and a **pleural effusion** in the setting of COPD. The pleural fluid analysis shows a **protein concentration of 4.0 g/dL** and **LDH of 280 U/L**, which are **high absolute values** strongly suggestive of an **exudative effusion**.
- An exudative effusion indicates inflammation and increased permeability of the pleural capillaries, allowing proteins and other large molecules to leak into the pleural space. Given the acute presentation with fever and respiratory symptoms in a patient with COPD, **pneumonia with associated para-pneumonic effusion** is the most likely diagnosis. The inflammatory process in pneumonia increases local capillary permeability, resulting in protein-rich fluid accumulation in the pleural space.
- This mechanism distinguishes exudates from transudates, which result from alterations in hydrostatic or oncotic pressures without primary inflammation.
*Decreased intrapleural pressure*
- This mechanism is associated with conditions like **atelectasis**, where a collapsed lung creates negative pressure in the pleural space, drawing fluid toward it.
- Effusions from decreased intrapleural pressure are typically **transudative** with low protein and LDH levels, which is inconsistent with this patient's findings. The acute febrile presentation also does not fit with atelectasis as the primary process.
*Decreased plasma oncotic pressure*
- This occurs in conditions like **nephrotic syndrome**, **cirrhosis**, or **severe malnutrition**, where low serum albumin reduces the oncotic pressure gradient.
- Decreased plasma oncotic pressure results in **transudative effusions** with low protein (typically < 3.0 g/dL) and low LDH, which contradicts this patient's high protein and LDH values. Additionally, there are no clinical features suggesting hypoalbuminemia.
*Increased pulmonary capillary pressure*
- This mechanism is characteristic of **congestive heart failure**, where elevated hydrostatic pressure in the pulmonary capillaries forces fluid into the pleural space.
- Heart failure typically produces **transudative effusions** with low protein and LDH. This patient's high protein (4.0 g/dL) and elevated LDH (280 U/L) are inconsistent with a hydrostatic mechanism. Furthermore, the acute fever and normal blood pressure argue against heart failure as the primary cause.
*Impaired lymphatic flow*
- Impaired lymphatic drainage can cause pleural effusions, as seen in **malignancy** (lymphatic obstruction), **chylothorax** (thoracic duct injury), or lymphatic abnormalities.
- While lymphatic obstruction can produce exudative effusions (especially in malignancy), the **acute onset with fever** points more strongly toward an infectious/inflammatory process rather than a chronic lymphatic disorder. Chylothorax would show milky fluid with high triglycerides, not seen here.
Question 638: A 59-year-old man is brought to the emergency department by a coworker for right arm weakness and numbness. The symptoms started suddenly 2 hours ago. His coworker also noticed his face appears to droop on the right side and his speech is slurred. He has a history of hypertension, hyperlipidemia, type 2 diabetes, and peripheral arterial disease. He works as a partner at a law firm and has been under more stress than usual lately. His father died of a stroke at age 70. The patient has smoked a pack of cigarettes daily for the last 40 years. He drinks two pints (750 mL) of whiskey each week. He takes aspirin, atorvastatin, lisinopril, and metformin daily. He is 167.6 cm (5 ft 6 in) tall and weighs 104.3 kg (230 lb); BMI is 37 kg/m2. His temperature is 37.1°C (98.8°F), pulse is 92/min, respirations are 15/min, and blood pressure is 143/92 mm Hg. He is fully alert and oriented. Neurological examination shows asymmetry of the face with droop of the lips on the right. There is 3/5 strength in right wrist flexion and extension, and right finger abduction. Sensation to light touch and pinprick is reduced throughout the right arm. Which of the following is the strongest predisposing factor for this patient's condition?
A. Excessive alcohol intake
B. Obesity
C. Hypertension (Correct Answer)
D. Increased stress
E. Hyperlipidemia
Explanation: ***Hypertension***
- **Hypertension is the single most important modifiable risk factor for stroke**, accounting for approximately 50% of stroke risk in population studies
- This patient's blood pressure of **143/92 mm Hg despite being on lisinopril** indicates poorly controlled hypertension, which significantly increases stroke risk
- Hypertension directly damages blood vessels through chronic endothelial injury and accelerates **atherosclerosis**, leading to both ischemic and hemorrhagic stroke
*Excessive alcohol intake*
- Heavy alcohol consumption (>2 drinks/day) increases stroke risk, particularly hemorrhagic stroke
- This patient's intake of two pints weekly (~5 drinks) is moderate-to-heavy but not the strongest risk factor compared to poorly controlled hypertension
- The association between alcohol and stroke is less consistent than that of hypertension
*Obesity*
- **Obesity (BMI 37 kg/m²)** increases stroke risk indirectly by promoting hypertension, diabetes, and dyslipidemia
- It is an important risk factor but acts primarily through these intermediate mechanisms rather than as a direct cause
- Hypertension remains the more potent and direct predisposing factor
*Increased stress*
- Chronic stress may contribute to stroke risk through effects on blood pressure, inflammation, and health behaviors
- However, stress is a **weak and indirect risk factor** with inconsistent epidemiological evidence
- It does not compare to the well-established, quantifiable impact of hypertension
*Hyperlipidemia*
- **Hyperlipidemia** promotes atherosclerosis and is an established risk factor for ischemic stroke
- The patient is on atorvastatin, which likely provides some protection
- While significant, hypertension has consistently been shown to have the **greatest population-attributable risk for stroke** among all modifiable factors
Question 639: A 56-year-old woman comes to the physician because of increasing muscle weakness in her shoulders and legs for 1 month. She has difficulties standing up and combing her hair. She also has had a skin rash on her face and hands for the past week. She has hypercholesterolemia treated with simvastatin. She has chronic eczema of her feet that is well-controlled with skin moisturizer and corticosteroid cream. Her mother and sister have thyroid disease. Vital signs are within normal limits. Examination shows facial erythema. A photograph of her hands is shown. Muscle strength is 3/5 in the iliopsoas, hamstring, deltoid, and biceps muscles. Sensation to pinprick, temperature, and vibration is intact. Further evaluation of this patient is most likely to show which of the following?
A. Anti-dsDNA antibodies
B. Symptom resolution on statin withdrawal
C. Elevated serum CA-125 (Correct Answer)
D. Intramuscular inclusion bodies
E. Pathological edrophonium test
Explanation: ***Elevated serum CA-125***
- The patient's presentation with **proximal muscle weakness**, **heliotrope rash** (facial erythema), and **Gottron papules** (rash on hands shown in photograph) is highly characteristic of **dermatomyositis**.
- **Dermatomyositis** in patients over 40-50 years has a **strong association with underlying malignancy** (10-25% of cases), particularly **ovarian, lung, gastric, and colorectal cancers** in adults.
- In women with dermatomyositis, **screening for ovarian cancer** is essential, and **elevated CA-125** may be detected during this evaluation.
- While not a direct diagnostic finding of dermatomyositis itself, elevated CA-125 is the most likely finding among the options given, as part of **paraneoplastic syndrome workup**.
*Intramuscular inclusion bodies*
- **Inclusion bodies** are characteristic of **inclusion body myositis (IBM)**, NOT dermatomyositis.
- IBM typically presents with **distal weakness** (finger flexors, knee extensors) more than proximal, affects patients >50 years, and has **no skin manifestations**.
- Dermatomyositis muscle biopsy shows **perifascicular atrophy** (pathognomonic), perivascular inflammation, and membrane attack complex deposition, but **not inclusion bodies**.
*Pathological edrophonium test*
- A pathological **edrophonium test** (positive Tensilon test) is characteristic of **myasthenia gravis**, which presents with **fluctuating muscle weakness**, often involving **ocular and bulbar muscles**.
- Myasthenia gravis is a **neuromuscular junction disorder** with **no rash** and would not explain the characteristic skin findings of dermatomyositis.
*Anti-dsDNA antibodies*
- **Anti-dsDNA antibodies** are highly specific for **systemic lupus erythematosus (SLE)**, which can cause myositis and various rashes (malar rash, discoid lupus).
- However, the specific cutaneous findings of **heliotrope rash** and **Gottron papules** are pathognomonic for dermatomyositis, not SLE.
- Dermatomyositis-specific antibodies include **anti-Mi-2**, **anti-Jo-1**, and **anti-TIF1-gamma** (associated with malignancy).
*Symptom resolution on statin withdrawal*
- **Statin-induced myopathy** can cause muscle pain, weakness, and elevated CK, but typically **does not cause a rash**.
- The presence of pathognomonic skin manifestations (**heliotrope rash** and **Gottron papules**) definitively points to **inflammatory myositis** (dermatomyositis), not statin myopathy.
- While statin myopathy should be considered in any patient on statins with muscle symptoms, the dermatological findings make this diagnosis unlikely.
Question 640: A previously healthy 61-year-old man comes to the physician because of a 6-month history of morning headaches. He also has fatigue and trouble concentrating on his daily tasks at work. He sleeps for 8 hours every night; his wife reports that he sometimes stops breathing for a few seconds while sleeping. His pulse is 71/min and blood pressure is 158/96 mm Hg. He is 178 cm (5 ft 10 in) tall and weighs 100 kg (220 lb); BMI is 31.6 kg/m2 . Which of the following is the most likely cause of this patient's hypertension?
A. Proliferation of adrenal chromaffin cells
B. Overproduction of cortisol
C. Hypophyseal neoplasm
D. Nocturnal upper airway obstruction (Correct Answer)
E. Hypersecretion of aldosterone
Explanation: ***Nocturnal upper airway obstruction***
- The patient's **obesity (BMI 31.6)**, **morning headaches**, fatigue, difficulty concentrating, and spousal report of **witnessed apneic episodes during sleep** are classic signs of **obstructive sleep apnea (OSA)**.
- OSA causes **intermittent hypoxia and hypercapnia** during sleep, leading to **sympathetic nervous system activation**, increased catecholamine release, and **sustained hypertension** even during waking hours.
- OSA is one of the most common **secondary causes of hypertension**, especially in obese patients.
*Proliferation of adrenal chromaffin cells*
- This describes a **pheochromocytoma**, which typically presents with **paroxysmal hypertension**, severe episodic headaches, palpitations, and diaphoresis (the classic "triad").
- While headaches are present, the **sleep-related breathing disturbances** and obesity are not consistent with pheochromocytoma.
*Overproduction of cortisol*
- This suggests **Cushing's syndrome**, which includes symptoms like central obesity, **moon facies, buffalo hump, purple striae**, muscle weakness, and easy bruising, along with hypertension.
- The patient lacks the classic cushingoid features, and the symptoms are more consistent with sleep-disordered breathing.
*Hypophyseal neoplasm*
- A pituitary tumor could cause hypertension if it leads to conditions like **Cushing's disease** (ACTH-secreting) or **acromegaly** (growth hormone excess).
- However, there are no specific symptoms pointing towards a pituitary tumor (no visual field defects, acromegalic features, or cushingoid appearance), and the prominent **witnessed apneas** fit OSA much better.
*Hypersecretion of aldosterone*
- This is characteristic of **primary hyperaldosteronism (Conn's syndrome)**, which commonly presents with hypertension, often accompanied by **hypokalemia**, muscle weakness, and polyuria.
- The patient's symptoms do not suggest electrolyte abnormalities or other classic signs of mineralocorticoid excess.