An obese 37-year-old woman is brought to the emergency department 2 hours after the onset of weakness in her left arm and leg. She fell from the stairs the day prior but did not have any loss of consciousness or nausea after the fall. She travels to Asia regularly on business; her last trip was 4 days ago. She has no history of serious illness. Her only medication is an oral contraceptive. Her temperature is 37.8°C (100°F), pulse is 113/min and regular, and blood pressure is 162/90 mm Hg. Examination shows decreased muscle strength on the left side. Deep tendon reflexes are 4+ on the left. Babinski sign is present on the left. The right lower leg is swollen, erythematous, and tender to palpation. Further evaluation is most likely to show which of the following?
Q792
A 35-year-old man is brought to the emergency department because of a 2-week history of abdominal cramps, vomiting, and constipation. He also reports having to urinate frequently and occasional leg pain. He has had similar episodes in the past. He has hypertension and peptic ulcer disease. Current medications include captopril and ranitidine. He appears depressed. Physical examination shows weakness in the extremities. Abdominal examination shows mild epigastric tenderness. There is no rebound or guarding. He has a restricted affect. Laboratory studies show elevated serum parathyroid hormone levels; serum calcium is 14.2 mg/dL. Abdominal ultrasonography shows multiple small calculi in the right kidney. Which of the following is most likely to provide rapid relief in this patient?
Q793
A 60-year-old man with a long-standing history of type 2 diabetes and hypertension managed with lisinopril and metformin presents with itchy skin. He also describes moderate nausea, vomiting, muscle weakness, and fatigue. The vital signs include: temperature 36.8°C (98.2°F), heart rate 98/min, respiratory rate 15/min, blood pressure 135/85 mm Hg, oxygen saturation 100% on room air. Physical exam is notable for pale conjunctivae, pitting edema, and ascites. Laboratory findings are shown below:
BUN 78 mg/dL
pCO2 25 mm Hg
Creatinine 7.2 mg/dL
Glucose 125 mg/dL
Serum chloride 102 mmol/L
Serum potassium 6.3 mEq/L
Serum sodium 130 mEq/L
Total calcium 1.3 mmol/L
Magnesium 1.2 mEq/L
Phosphate 1.9 mmol/L
Hemoglobin 9.5 g/dL
MCV 86 μm3
Bicarbonate (HCO3) 10 mmol/L
Shrunken kidneys are identified on renal ultrasound. The doctor explains to the patient that he will likely need dialysis due to his significant renal failure until a renal transplant can be performed. The patient is concerned because he is very busy and traveling a lot for work. Given his lifestyle requirements, what is a potential complication of the most appropriate dialysis modality for this patient?
Q794
Twelve days after undergoing a cadaveric renal transplant for adult polycystic kidney disease, a 23-year-old man has pain in the right lower abdomen and generalized fatigue. During the past 4 days, he has had decreasing urinary output. Creatinine concentration was 2.3 mg/dL on the second postoperative day. Current medications include prednisone, cyclosporine, azathioprine, and enalapril. His temperature is 38°C (100.4°F), pulse is 103/min, and blood pressure is 168/98 mm Hg. Examination reveals tenderness to palpation on the graft site. Creatinine concentration is 4.3 mg/dL. A biopsy of the transplanted kidney shows tubulitis. C4d staining is negative. Which of the following is the most likely cause of this patient's findings?
Q795
A 67-year-old Caucasian female presents to her primary care physician after a screening DEXA scan reveals a T-score of -3.0. Laboratory work-up reveals normal serum calcium, phosphate, vitamin D, and PTH levels. She smokes 1-2 cigarettes per day. Which of the following measures would have reduced this patient's risk of developing osteoporosis?
Q796
A 65-year-old man is brought to the emergency department because of a 3-day history of increasing shortness of breath and chest pain. He has had a productive cough with foul-smelling sputum for 1 week. He has gastritis as well as advanced Parkinson disease and currently lives in an assisted-living community. He smoked one pack of cigarettes daily for 40 years but quit 5 years ago. He has a 30-year history of alcohol abuse but has not consumed any alcohol in the past 5 years. His temperature is 39.3°C (102.7°F), he is tachycardic and tachypneic and his oxygen saturation is 77% on room air. Auscultation of the lung shows rales and decreased breath sounds over the right upper lung field. Examination shows a resting tremor. Laboratory studies show:
Hematocrit 38%
Leukocyte count 17,000/mm3
Platelet count 210,000/mm3
Lactic acid 4.1 mmol/L (N=0.5–1.5)
A x-ray of the chest shows infiltrates in the right upper lobe. Which of the following is the most significant predisposing factor for this patient's respiratory symptoms?
Q797
A 62-year-old woman with type 2 diabetes mellitus comes to the physician because of a 3-month history of fatigue and weakness. Her hemoglobin A1c concentration was 13.5% 12 weeks ago. Her blood pressure is 152/92 mm Hg. Examination shows lower extremity edema. Serum studies show:
K+ 5.1 mEq/L
Phosphorus 5.0 mg/dL
Ca2+ 7.8 mg/dL
Urea nitrogen 60 mg/dL
Creatinine 2.2 mg/dL
Which of the following is the best parameter for early detection of this patient’s renal condition?
Q798
A 10-year-old boy is brought to the pediatrician by his father because of recent changes in his behavior. His father states that he has noticed that the boy has begun to appear less coordinated than normal and has had frequent falls. On exam, the pediatrician observes pes cavus and hammer toes. The pediatrician makes a presumptive diagnosis based on these findings and recommends a formal echocardiogram. The pediatrician is most likely concerned about which of the following cardiovascular defects?
Q799
A 55-year-old man is brought to the emergency department 30 minutes after the sudden onset of severe, migrating anterior chest pain, shortness of breath, and sweating at rest. He has hypertension, hypercholesterolemia, and type 2 diabetes mellitus. Medications include atorvastatin, hydrochlorothiazide, lisinopril, and metformin. He has smoked one pack of cigarettes daily for 25 years. He is in severe distress. His pulse is 110/min, respirations are 20/min, and blood pressure is 150/85 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. Cardiac examination shows a grade 3/6, high-pitched, blowing, diastolic murmur heard best over the right sternal border. The lungs are clear to auscultation. Femoral pulses are decreased bilaterally. An ECG shows sinus tachycardia and left ventricular hypertrophy. Which of the following is the most likely diagnosis?
Q800
A 55-year-old man presents to his primary care physician for a new patient appointment. The patient states that he feels well and has no concerns at this time. The patient has a past medical history of hypertension, an elevated fasting blood glucose, and is not currently taking any medications. His blood pressure is 177/118 mmHg, pulse is 90/min, respirations are 16/min, and oxygen saturation is 97% on room air. Physical exam is notable for an obese man with atrophy of his limbs and striae on his abdomen. Laboratory values are notable for a blood glucose of 175 mg/dL. Which of the following is the best next step in evaluation?
Cardiology US Medical PG Practice Questions and MCQs
Question 791: An obese 37-year-old woman is brought to the emergency department 2 hours after the onset of weakness in her left arm and leg. She fell from the stairs the day prior but did not have any loss of consciousness or nausea after the fall. She travels to Asia regularly on business; her last trip was 4 days ago. She has no history of serious illness. Her only medication is an oral contraceptive. Her temperature is 37.8°C (100°F), pulse is 113/min and regular, and blood pressure is 162/90 mm Hg. Examination shows decreased muscle strength on the left side. Deep tendon reflexes are 4+ on the left. Babinski sign is present on the left. The right lower leg is swollen, erythematous, and tender to palpation. Further evaluation is most likely to show which of the following?
A. Atrial fibrillation
B. Patent foramen ovale (Correct Answer)
C. Atrial myxoma
D. Ventricular septal defect
E. Carotid artery dissection
Explanation: ***Patent foramen ovale***
- This patient presents with a **cryptogenic stroke** (stroke of undetermined cause) in the context of being **obese**, taking **oral contraceptives**, recent **long-distance travel**, and symptoms of a **deep vein thrombosis (DVT)** in her right leg.
- A **paradoxical embolism** through a **patent foramen ovale (PFO)** is a strong possibility, where a clot from the DVT could bypass the pulmonary circulation and enter the systemic circulation, leading to a stroke.
*Atrial fibrillation*
- While **atrial fibrillation** is a common cause of **embolic stroke**, the patient's pulse is described as **regular**, making this diagnosis less likely.
- There are no other indications of atrial fibrillation on physical exam, such as an irregularly irregular pulse.
*Atrial myxoma*
- An **atrial myxoma** can cause **embolic stroke** due to tumor fragments breaking off, but this is a rare cause.
- There are no other signs or symptoms suggestive of a cardiac tumor, such as constitutional symptoms or cardiac murmurs.
*Ventricular septal defect*
- A **ventricular septal defect (VSD)** typically causes a left-to-right shunt and is associated with a **loud holosystolic murmur** at the lower left sternal border.
- While a **right-to-left shunt** can occur in the presence of **pulmonary hypertension (Eisenmenger syndrome)**, there is no mention of a murmur or signs of pulmonary hypertension.
*Carotid artery dissection*
- **Carotid artery dissection** can cause stroke, often preceded by **neck pain** or **headache**, which is not reported by the patient.
- The presence of a **DVT** and associated risk factors for thromboembolism makes a paradoxical embolism a more probable cause in this clinical scenario.
Question 792: A 35-year-old man is brought to the emergency department because of a 2-week history of abdominal cramps, vomiting, and constipation. He also reports having to urinate frequently and occasional leg pain. He has had similar episodes in the past. He has hypertension and peptic ulcer disease. Current medications include captopril and ranitidine. He appears depressed. Physical examination shows weakness in the extremities. Abdominal examination shows mild epigastric tenderness. There is no rebound or guarding. He has a restricted affect. Laboratory studies show elevated serum parathyroid hormone levels; serum calcium is 14.2 mg/dL. Abdominal ultrasonography shows multiple small calculi in the right kidney. Which of the following is most likely to provide rapid relief in this patient?
A. Normal saline and intravenous calcitonin therapy (Correct Answer)
B. Intravenous pamidronate therapy
C. Normal saline and intravenous fentanyl therapy
D. Normal saline and intravenous furosemide therapy
E. Reduction of dietary intake of calcium
Explanation: ***Normal saline and intravenous calcitonin therapy***
- The patient presents with **severe hypercalcemia** (14.2 mg/dL) and symptoms like abdominal cramps, vomiting, constipation, polyuria, leg pain, and weakness. **Normal saline** effectively rehydrates the patient and promotes renal calcium excretion, while **intravenous calcitonin** rapidly reduces serum calcium by inhibiting osteoclast activity.
- This combination provides a **rapid reduction in serum calcium**, which is crucial for symptomatic relief in severe hypercalcemia.
*Intravenous pamidronate therapy*
- **Bisphosphonates** like pamidronate are effective in treating hypercalcemia, but their **onset of action is slower** (2-4 days) compared to calcitonin.
- While ultimately helpful, pamidronate would not provide the immediate relief needed for this patient's acute symptoms.
*Normal saline and intravenous fentanyl therapy*
- **Fentanyl** is an opioid pain reliever and does not address the underlying **hypercalcemia** or its symptoms.
- While it could help with acute pain (e.g., from renal calculi), it doesn't provide symptomatic relief for hypercalcemia-related issues like vomiting, constipation, or weakness, and it won't lower calcium levels.
*Normal saline and intravenous furosemide therapy*
- **Loop diuretics** like furosemide can increase renal calcium excretion but should only be used *after* adequate rehydration with normal saline to prevent volume depletion and worsening hypercalcemia.
- Furosemide alone is not sufficient to rapidly correct severe hypercalcemia and can potentially lead to dehydration if not managed carefully alongside vigorous fluid resuscitation.
*Reduction of dietary intake of calcium*
- While appropriate for long-term management of hypercalcemia, reducing dietary calcium intake has an **insignificant and slow effect** on severe hypercalcemia.
- It would not provide the rapid relief necessary for the patient's acute and symptomatic hypercalcemic crisis.
Question 793: A 60-year-old man with a long-standing history of type 2 diabetes and hypertension managed with lisinopril and metformin presents with itchy skin. He also describes moderate nausea, vomiting, muscle weakness, and fatigue. The vital signs include: temperature 36.8°C (98.2°F), heart rate 98/min, respiratory rate 15/min, blood pressure 135/85 mm Hg, oxygen saturation 100% on room air. Physical exam is notable for pale conjunctivae, pitting edema, and ascites. Laboratory findings are shown below:
BUN 78 mg/dL
pCO2 25 mm Hg
Creatinine 7.2 mg/dL
Glucose 125 mg/dL
Serum chloride 102 mmol/L
Serum potassium 6.3 mEq/L
Serum sodium 130 mEq/L
Total calcium 1.3 mmol/L
Magnesium 1.2 mEq/L
Phosphate 1.9 mmol/L
Hemoglobin 9.5 g/dL
MCV 86 μm3
Bicarbonate (HCO3) 10 mmol/L
Shrunken kidneys are identified on renal ultrasound. The doctor explains to the patient that he will likely need dialysis due to his significant renal failure until a renal transplant can be performed. The patient is concerned because he is very busy and traveling a lot for work. Given his lifestyle requirements, what is a potential complication of the most appropriate dialysis modality for this patient?
A. Excessive bleeding
B. Muscle cramping
C. Hypotension
D. Hypertriglyceridemia (Correct Answer)
E. Hypoglycemia
Explanation: ***Hypertriglyceridemia***
- The patient's **lifestyle requirements** (busy, traveling a lot) suggest **peritoneal dialysis (PD)** as the most appropriate modality due to its flexibility and home-based nature.
- **Hypertriglyceridemia** is a common complication of PD due to the absorption of glucose from the dialysate, which stimulates hepatic triglyceride synthesis.
*Excessive bleeding*
- This is a rare complication in both hemodialysis and peritoneal dialysis.
- While **anti-coagulation** is used in hemodialysis, it's carefully monitored, and significant bleeding is not a typical long-term complication of the chosen modality (PD).
*Muscle cramping*
- **Muscle cramps** can occur with hemodialysis, typically due to rapid fluid and electrolyte shifts.
- This is less common in peritoneal dialysis, which involves a slower and more continuous exchange process.
*Hypotension*
- **Hypotension** can be a complication of hemodialysis due to rapid fluid removal.
- Peritoneal dialysis, with its gradual fluid exchange, is generally less associated with significant hypotensive episodes.
*Hypoglycemia*
- The **glucose-rich dialysate** used in peritoneal dialysis can actually lead to **hyperglycemia**, not hypoglycemia, especially in diabetic patients.
- Regular insulin adjustments are often required for diabetic patients on PD.
Question 794: Twelve days after undergoing a cadaveric renal transplant for adult polycystic kidney disease, a 23-year-old man has pain in the right lower abdomen and generalized fatigue. During the past 4 days, he has had decreasing urinary output. Creatinine concentration was 2.3 mg/dL on the second postoperative day. Current medications include prednisone, cyclosporine, azathioprine, and enalapril. His temperature is 38°C (100.4°F), pulse is 103/min, and blood pressure is 168/98 mm Hg. Examination reveals tenderness to palpation on the graft site. Creatinine concentration is 4.3 mg/dL. A biopsy of the transplanted kidney shows tubulitis. C4d staining is negative. Which of the following is the most likely cause of this patient's findings?
A. Drug-induced nephrotoxicity
B. Allorecognition with T cell activation (Correct Answer)
C. Irreversible fibrosis of the glomerular vessels
D. Donor T cells from the graft
E. Preformed cytotoxic antibodies against class I HLA
Explanation: ***Allorecognition with T cell activation***
- The patient's symptoms (pain at graft site, fatigue, decreasing urinary output, elevated creatinine) 12 days post-transplant, along with **tubulitis on biopsy** and negative **C4d staining**, are indicative of acute cellular rejection, mediated primarily by **T-cell recognition of donor HLA antigens**.
- **Hypertension** and **fever** also support acute rejection, and the immunosuppressive regimen may not be fully effective in preventing this T-cell mediated response.
*Drug-induced nephrotoxicity*
- While cyclosporine and enalapril can cause kidney injury, the **histological finding of tubulitis** is highly specific for acute cellular rejection, not typically seen with drug-induced nephrotoxicity alone.
- Drug-induced nephrotoxicity usually presents with a more **gradual rise in creatinine** and may lack the systemic signs like fever or the specific pathological features of rejection.
*Irreversible fibrosis of the glomerular vessels*
- This description is more consistent with **chronic allograft nephropathy** or long-term damage, which typically develops months to years after transplantation, not within 12 days.
- The findings described (pain, fever, tubulitis) point to an acute process, not chronic fibrosis.
*Donor T cells from the graft*
- This scenario describes **graft-versus-host disease (GVHD)**, which is rare in solid organ transplantation due to the much smaller lymphocyte load compared to bone marrow transplants.
- GVHD typically affects the skin, liver, and gut, and while it involves T-cell mediated injury, the primary damage in renal transplant rejection is directed at the transplanted kidney by the recipient's immune system.
*Preformed cytotoxic antibodies against class I HLA*
- This describes **hyperacute rejection**, which occurs within minutes to hours of transplantation due to pre-existing antibodies in the recipient against donor antigens.
- The patient's symptoms developing 12 days post-transplant, along with the biopsy showing tubulitis and negative C4d staining (indicating absence of significant antibody-mediated complement activation), rule out hyperacute rejection.
Question 795: A 67-year-old Caucasian female presents to her primary care physician after a screening DEXA scan reveals a T-score of -3.0. Laboratory work-up reveals normal serum calcium, phosphate, vitamin D, and PTH levels. She smokes 1-2 cigarettes per day. Which of the following measures would have reduced this patient's risk of developing osteoporosis?
A. Weight loss
B. Reduced physical activity to decrease the chance of a fall
C. Initiating a swimming exercise program three days per week
D. Calcium and vitamin D supplementation
E. Smoking cessation (Correct Answer)
Explanation: ***Smoking cessation***
- **Smoking** is a well-established, modifiable risk factor for osteoporosis that directly impairs bone metabolism
- Cigarette smoking **decreases osteoblast activity**, increases **bone resorption**, and reduces intestinal calcium absorption
- This patient is **actively smoking 1-2 cigarettes per day**, making cessation the most relevant preventive measure for her specific situation
- **Smoking cessation** would have directly addressed a harmful exposure that contributed to her bone loss
*Calcium and vitamin D supplementation*
- While important for bone health, this patient's laboratory work-up shows **normal serum calcium and vitamin D levels**
- Supplementation beyond adequate levels has **limited additional benefit** for osteoporosis prevention in patients with normal baseline values
- Supplementation is most beneficial in patients with documented **deficiency** or inadequate dietary intake
*Weight loss*
- **Weight loss** and being underweight are actually **risk factors for osteoporosis**
- Lower body weight reduces mechanical loading on bones, which is necessary for maintaining bone density
- Weight-bearing stress stimulates bone formation through mechanotransduction
*Initiating a swimming exercise program three days per week*
- While **swimming** is excellent for cardiovascular fitness and overall health, it is **not a weight-bearing exercise**
- Osteoporosis prevention requires **weight-bearing or resistance exercises** such as walking, jogging, dancing, or strength training
- These activities provide the mechanical stress needed to stimulate bone formation
*Reduced physical activity to decrease the chance of a fall*
- **Reducing physical activity** accelerates bone loss due to decreased mechanical loading
- While fall prevention is important in osteoporosis management, it should focus on **environmental modifications** and **balance training**, not activity reduction
- Maintaining appropriate physical activity is essential for preserving bone density
Question 796: A 65-year-old man is brought to the emergency department because of a 3-day history of increasing shortness of breath and chest pain. He has had a productive cough with foul-smelling sputum for 1 week. He has gastritis as well as advanced Parkinson disease and currently lives in an assisted-living community. He smoked one pack of cigarettes daily for 40 years but quit 5 years ago. He has a 30-year history of alcohol abuse but has not consumed any alcohol in the past 5 years. His temperature is 39.3°C (102.7°F), he is tachycardic and tachypneic and his oxygen saturation is 77% on room air. Auscultation of the lung shows rales and decreased breath sounds over the right upper lung field. Examination shows a resting tremor. Laboratory studies show:
Hematocrit 38%
Leukocyte count 17,000/mm3
Platelet count 210,000/mm3
Lactic acid 4.1 mmol/L (N=0.5–1.5)
A x-ray of the chest shows infiltrates in the right upper lobe. Which of the following is the most significant predisposing factor for this patient's respiratory symptoms?
A. Tobacco use history
B. Parkinson disease (Correct Answer)
C. Past history of alcohol abuse
D. Gastritis
E. Living in an assisted-living community
Explanation: ***Parkinson disease***
- **Parkinson disease** impairs the normal swallowing reflex, leading to **dysphagia** and an increased risk of **aspiration**, which is the most likely cause of the patient's **foul-smelling sputum** (indicating anaerobic organisms from oral flora).
- The **right upper lobe infiltrate** can occur with aspiration pneumonia, particularly involving the **posterior segment** in patients who aspirate while supine or semi-recumbent, which is common in patients with advanced Parkinson disease.
- The resting tremor mentioned in the physical exam further confirms the diagnosis of Parkinson disease, linking it directly to his aspiration risk.
*Tobacco use history*
- While a significant **smoking history** increases the risk of chronic obstructive pulmonary disease (COPD) and lung cancer, it does not directly lead to **foul-smelling sputum** and the acute aspiration event described.
- The patient quit smoking 5 years ago, reducing his immediate risk compared to an active smoker.
*Past history of alcohol abuse*
- **Chronic alcohol abuse** can compromise the immune system and increase the risk of pneumonia, but this patient has not consumed alcohol in the past 5 years.
- Alcohol abuse does not specifically predispose to **aspiration events** in the same direct way Parkinson disease does through impaired swallowing mechanisms.
*Gastritis*
- **Gastritis** primarily affects the stomach lining and is not a direct predisposing factor for severe respiratory infections like pneumonia, especially aspiration pneumonia with **foul-smelling sputum**.
- It does not impact swallowing reflexes or increase the risk of aspiration.
*Living in an assisted-living community*
- Living in a communal setting like an **assisted-living facility** can increase exposure to infectious agents and healthcare-associated pneumonia, but it does not specifically explain the risk of **aspiration pneumonia** with **foul-smelling sputum**.
- This factor is less specific to the underlying pathophysiological mechanism of his current illness compared to Parkinson disease.
Question 797: A 62-year-old woman with type 2 diabetes mellitus comes to the physician because of a 3-month history of fatigue and weakness. Her hemoglobin A1c concentration was 13.5% 12 weeks ago. Her blood pressure is 152/92 mm Hg. Examination shows lower extremity edema. Serum studies show:
K+ 5.1 mEq/L
Phosphorus 5.0 mg/dL
Ca2+ 7.8 mg/dL
Urea nitrogen 60 mg/dL
Creatinine 2.2 mg/dL
Which of the following is the best parameter for early detection of this patient’s renal condition?
A. Serum total protein
B. Serum creatinine
C. Urinary red blood cell casts
D. Serum urea nitrogen
E. Urinary albumin (Correct Answer)
Explanation: ***Urinary albumin***
- **Microalbuminuria** is often the earliest detectable sign of **diabetic nephropathy**, occurring before changes in GFR or serum creatinine become apparent.
- Regular screening for urinary albumin in diabetic patients allows for early intervention to slow the progression of **renal damage**.
*Serum total protein*
- **Hypoalbuminemia** can be seen in advanced renal disease due to significant proteinuria, but it is not an early marker.
- Other conditions like **liver disease** or **malnutrition** can also cause altered serum total protein, making it less specific for early renal damage.
*Serum creatinine*
- **Serum creatinine** levels rise significantly only after a substantial portion of kidney function (around 50%) has been lost.
- Therefore, it is a marker of established renal dysfunction rather than an early indicator.
*Urinary red blood cell casts*
- The presence of **red blood cell casts** in urine indicates **glomerulonephritis** or other inflammatory conditions affecting the glomeruli.
- While concerning, it is not the typical or earliest presentation of **diabetic nephropathy**, which primarily involves proteinuria.
*Serum urea nitrogen*
- **Blood urea nitrogen (BUN)** levels, like creatinine, increase with declining kidney function and are used to assess the severity of **renal impairment**.
- However, BUN levels can also be influenced by factors like **hydration status** and **protein intake**, and they are not an early marker of nascent renal disease.
Question 798: A 10-year-old boy is brought to the pediatrician by his father because of recent changes in his behavior. His father states that he has noticed that the boy has begun to appear less coordinated than normal and has had frequent falls. On exam, the pediatrician observes pes cavus and hammer toes. The pediatrician makes a presumptive diagnosis based on these findings and recommends a formal echocardiogram. The pediatrician is most likely concerned about which of the following cardiovascular defects?
A. Tetralogy of Fallot
B. Aortic cystic medial necrosis
C. Hypertrophic cardiomyopathy (Correct Answer)
D. Coarctation of the aorta
E. Endocardial cushion defect
Explanation: **Hypertrophic cardiomyopathy**
- The constellation of **neurological symptoms** (ataxia, frequent falls) and **skeletal deformities** (**pes cavus**, **hammer toes**) is classic for **Friedreich ataxia**.
- **Hypertrophic cardiomyopathy** is a common and severe cardiac complication in patients with **Friedreich ataxia**, making the recommended echocardiogram highly pertinent for screening and management.
*Tetralogy of Fallot*
- This is a **cyanotic congenital heart defect** typically presenting in infancy with **cyanosis**, **dyspnea**, and **tet spells**, not usually associated with later-onset neurological and skeletal issues like those described.
- While it can manifest with exercise intolerance, it does not directly lead to **pes cavus** or **hammer toes** as part of a systemic syndrome.
*Aortic cystic medial necrosis*
- This condition is associated with disorders like **Marfan syndrome** due to underlying connective tissue defects, predisposing to **aortic dissection** or **aneurysm**.
- It does not present with the specific neurological and skeletal findings seen here, and its cardiac manifestations (e.g., aortic root dilation) are distinct from hypertrophic cardiomyopathy.
*Coarctation of the aorta*
- This is a **narrowing of the aorta**, typically presenting with **hypertension in the upper extremities**, **diminished femoral pulses**, and sometimes **heart failure** or **murmurs**.
- It is not directly linked to neurological degeneration, **pes cavus**, or **hammer toes**, and is not a common complication of Friedreich ataxia.
*Endocardial cushion defect*
- Also known as **atrioventricular septal defect**, this is a **congenital heart defect** common in children with **Down syndrome**.
- It typically presents with symptoms of **heart failure** in infancy or early childhood due to large shunts, and does not cause the described neurological and skeletal abnormalities.
Question 799: A 55-year-old man is brought to the emergency department 30 minutes after the sudden onset of severe, migrating anterior chest pain, shortness of breath, and sweating at rest. He has hypertension, hypercholesterolemia, and type 2 diabetes mellitus. Medications include atorvastatin, hydrochlorothiazide, lisinopril, and metformin. He has smoked one pack of cigarettes daily for 25 years. He is in severe distress. His pulse is 110/min, respirations are 20/min, and blood pressure is 150/85 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. Cardiac examination shows a grade 3/6, high-pitched, blowing, diastolic murmur heard best over the right sternal border. The lungs are clear to auscultation. Femoral pulses are decreased bilaterally. An ECG shows sinus tachycardia and left ventricular hypertrophy. Which of the following is the most likely diagnosis?
A. Esophageal rupture
B. Pulmonary embolism
C. Aortic dissection (Correct Answer)
D. Papillary muscle rupture
E. Spontaneous pneumothorax
Explanation: ***Aortic dissection***
- The sudden onset of **severe, migrating anterior chest pain**, autonomic symptoms (sweating at rest), and **decreased bilateral femoral pulses** are highly characteristic of aortic dissection.
- The presence of a new **diastolic murmur** (indicating aortic insufficiency due to dissection extending to the aortic valve), along with a history of **hypertension** and **smoking**, further supports this diagnosis.
- **Decreased bilateral femoral pulses** suggest involvement of the descending aorta compromising flow to both lower extremities.
*Esophageal rupture*
- While esophageal rupture can cause **sudden, severe chest pain**, it typically presents with **odynophagia**, **vomiting**, and often **subcutaneous emphysema** or **Hamman's sign**, which are absent here.
- It would not explain the **diastolic murmur** or the **bilateral decreased femoral pulses**.
*Pulmonary embolism*
- **Shortness of breath** and **chest pain** can occur with pulmonary embolism, but the pain is typically **pleuritic** rather than migrating.
- It would not cause a **diastolic murmur** or **decreased peripheral pulses**.
*Papillary muscle rupture*
- Papillary muscle rupture is a complication of **myocardial infarction**, usually causing **acute severe mitral regurgitation** with a new **systolic murmur** and signs of **heart failure**.
- The patient's presentation with migrating pain and a **diastolic murmur** is inconsistent with this diagnosis.
*Spontaneous pneumothorax*
- A spontaneous pneumothorax causes **sudden, sharp, pleuritic chest pain** and **dyspnea**, often accompanied by **decreased breath sounds** on the affected side.
- It would not cause a **diastolic murmur** or **decreased femoral pulses**.
Question 800: A 55-year-old man presents to his primary care physician for a new patient appointment. The patient states that he feels well and has no concerns at this time. The patient has a past medical history of hypertension, an elevated fasting blood glucose, and is not currently taking any medications. His blood pressure is 177/118 mmHg, pulse is 90/min, respirations are 16/min, and oxygen saturation is 97% on room air. Physical exam is notable for an obese man with atrophy of his limbs and striae on his abdomen. Laboratory values are notable for a blood glucose of 175 mg/dL. Which of the following is the best next step in evaluation?
A. Hydrochlorothiazide
B. MRI of the head
C. Metformin
D. Weight loss
E. Dexamethasone suppression test (Correct Answer)
Explanation: ***Dexamethasone suppression test***
- The patient presents with **atrophy of the limbs** with concurrent **striae on the abdomen**, uncontrolled hypertension, and elevated blood glucose, which are all classic signs of **Cushing's syndrome**.
- A **dexamethasone suppression test** is the best initial diagnostic step to confirm Cushing's syndrome by assessing the body's cortisol regulation.
*Hydrochlorothiazide*
- While the patient has **hypertension**, treating the symptom without addressing the underlying cause (Cushing's syndrome) would be insufficient and potentially delay proper diagnosis.
- **Hydrochlorothiazide** is an antihypertensive, but without addressing the likely cortisol excess, blood pressure control will be challenging.
*MRI of the head*
- An **MRI of the head** (specifically the pituitary) would be considered after biochemical confirmation of Cushing's syndrome to localize a potential tumor, but it is not the initial diagnostic step.
- Imaging is performed *after* biochemical tests indicate cortisol excess, to differentiate between pituitary, adrenal, or ectopic causes.
*Metformin*
- The patient has **elevated blood glucose**, but initiating an antidiabetic medication like **metformin** before evaluating for Cushing's syndrome would be treating a symptom without identifying the root cause.
- Diabetes in this context is likely secondary to excess cortisol, so managing it effectively requires addressing the underlying endocrine disorder.
*Weight loss*
- While **weight loss** is generally beneficial for hypertension and diabetes, in the context of Cushing's syndrome with **limb atrophy** and **central obesity**, focusing solely on weight loss without addressing the hormonal imbalance would be ineffective.
- The characteristic fat redistribution in Cushing's syndrome makes simple weight loss difficult and less impactful until cortisol levels are managed.