A 55-year-old man presents to the emergency department for chest pain. He states that the pain started last night and has persisted until this morning. He describes the pain as in his chest and radiating into his back between his scapulae. The patient has a past medical history of alcohol abuse and cocaine abuse. He recently returned from vacation on a transatlantic flight. The patient has smoked 1 pack of cigarettes per day for the past 20 years. His temperature is 99.5°F (37.5°C), blood pressure is 167/118 mmHg, pulse is 120/min, and respirations are 22/min. Physical exam reveals tachycardia and clear air movement bilaterally on cardiopulmonary exam. Which of the following is also likely to be found in this patient?
Q662
A 67-year old woman is brought to the emergency department after she lost consciousness while at home. Her daughter was with her at the time and recalls that her mother was complaining of a diffuse headache and nausea about 2 hours before the incident. The daughter says that her mother has not had any recent falls and was found sitting in a chair when she lost consciousness. She has hypertension. Current medications include amlodipine, a daily multivitamin, and acetaminophen. She has smoked 1/2 pack of cigarettes daily for the past 45 years. Her pulse is 92/min, respirations are 10/min, and blood pressure is 158/100 mm Hg. She is disoriented and unable to follow commands. Examination shows nuchal rigidity. She has flexor posturing to painful stimuli. Fundoscopic examination is notable for bilateral vitreous hemorrhages. Laboratory studies are within normal limits. An emergent non-contrast CT scan of the head is obtained and shows a diffuse hemorrhage at the base of the brain that is largest over the left hemisphere. Which of the following is the most likely cause of this patient's symptoms?
Q663
A 33-year-old woman comes to the physician because of left leg pain and swelling for 1 day. She has had two miscarriages but otherwise has no history of serious illness. Physical examination shows stiff, swollen finger joints. The left calf circumference is larger than the right and there is a palpable cord in the left popliteal fossa. Laboratory studies show a prothrombin time of 12 seconds and an activated partial thromboplastin time of 51 seconds. Which of the following is most likely to confirm the diagnosis?
Q664
A 57-year-old man comes to the physician two weeks after a blood pressure of 160/92 mm Hg was measured at a routine health maintenance examination. Subsequent home blood pressure measurements since the last visit have been: 159/98 mm Hg, 161/102 mm Hg, and 152/95 mm Hg. Over the past 3 years, the patient has had a 10-kg (22-lb) weight gain. He has type 2 diabetes mellitus. He does not follow any specific diet; he usually eats sandwiches at work and fried chicken or burger for dinner. He says that he has been struggling with a stressful project at work recently. His mother was diagnosed with hypertension at the age of 45. The patient's only medication is metformin. His pulse is 82/min, and blood pressure now is 158/98 mm Hg. The patient is 178 cm (5 ft 10 in) tall and weighs 133 kg (293 lb); BMI is 42 kg/m2. Physical examination shows no other abnormalities except for significant central obesity. Fasting serum studies show:
Total cholesterol 220 mg/dL
HDL-cholesterol 25 mg/dL
Triglycerides 198 mg/dL
Glucose 120 mg/dL
Which of the following is the most important factor in the development of this patient's condition?
Q665
A 67-year-old man is brought to the emergency department because of increasing shortness of breath that began while playing outdoors with his grandson. He has a history of asthma but does not take any medications for it. On arrival, he is alert and oriented. He is out of breath and unable to finish his sentences. His pulse is 130/min, respirations are 23/min and labored, and blood pressure is 110/70 mm Hg. Physical examination shows nasal flaring and sternocleidomastoid muscle use. Pulmonary exam shows poor air movement bilaterally but no wheezing. Cardiac examination shows no abnormalities. Oxygen is administered via non-rebreather mask. He is given three albuterol nebulizer treatments, inhaled ipratropium, and intravenous methylprednisolone. The patient is confused and disoriented. Arterial blood gas analysis shows:
pH 7.34
Pco2 44 mm Hg
Po2 54 mm Hg
O2 saturation 87%
Which of the following is the most appropriate next step in management?
Q666
A 65-year-old woman presents to her physician with a persistent and debilitating cough which began 3 weeks ago, and chest pain accompanied by shortness of breath for the past week. Past medical history is significant for breast carcinoma 10 years ago treated with mastectomy, chemotherapy and radiation, a hospitalization a month ago for pneumonia that was treated with antibiotics, hypertension, and diabetes mellitus. Medications include chlorthalidone and metformin. She does not smoke but her husband has been smoking 3 packs a day for 30 years. Today her respiratory rate is 20/min and the blood pressure is 150/90 mm Hg. Serum Na is 140 mmol/L, serum K is 3.8 mmol/L and serum Ca is 12.2 mg/dL. A chest X-ray (shown in image) is performed. Which of the following is the most likely diagnosis?
Q667
A 25-year-old female comes to the physician because of fever and worsening cough for the past 4-days. She has had several episodes of otitis media, sinusitis, and an intermittent cough productive of green sputum for the past 2-years. She has also noticed some streaks of blood in the sputum lately. Her temperature is 38°C (100.4°F). Auscultation of the chest reveals crackles and rhonchi bilaterally. Heart sounds cannot be heard along the left lower chest. A CT scan of the chest reveals bronchiectasis and dextrocardia. Which of the following additional findings is most likely in this patient?
Q668
A 12-year-old boy presents with progressive clumsiness and difficulty walking. He walks like a 'drunken-man' and has experienced frequent falls. He was born at term and has gone through normal developmental milestones. His vaccination profile is up to date. He denies fever, chills, nausea, vomiting, chest pain, and shortness of breath. He has no history of alcohol use or illicit drug use. His elder brother experienced the same symptoms. The physical examination reveals normal higher mental functions. His extraocular movements are normal. His speech is mildly dysarthric. His muscle tone and strength in all 4 limbs are normal. His ankle reflexes are absent bilaterally with positive Babinski’s signs. Both vibration and proprioception are absent bilaterally. When he is asked to stand with his eyes closed and with both feet close together, he sways from side to side, unable to stand still. X-ray results show mild scoliosis. Electrocardiogram results show widespread T-wave inversions. His fasting blood glucose level is 143 mg/dL. What is the most likely diagnosis?
Q669
A 36-year-old woman presents to the emergency department with chest discomfort and fatigue. She reports that her symptoms began approximately 1 week ago and are associated with shortness of breath, swelling of her legs, and worsening weakness. She’s been having transitory fevers for about 1 month and denies having similar symptoms in the past. Medical history is significant for systemic lupus erythematosus (SLE) treated with hydroxychloroquine. She had a SLE flare approximately 2 weeks prior to presentation, requiring a short course of prednisone. Physical exam was significant for a pericardial friction rub. An electrocardiogram showed widespread ST-segment elevation and PR depression. After extensive work-up, she was admitted for further evaluation, treatment, and observation. Approximately 2 days after admission she became unresponsive. Her temperature is 100°F (37.8°C), blood pressure is 75/52 mmHg, pulse is 120/min, and respirations are 22/min. Heart sounds are muffled. Which of the following is a clinical finding that will most likely be found in this patient?
Q670
A 54-year-old man presents to the office complaining of recent shortness of breath and fever. He has a history of a chronic cough which is progressively getting worse. His medical history is significant for hypertension and diabetes mellitus, both controlled with medication. He has been working in a sandblasting factory for over 3 decades. His temperature is 37.7°C (99.9°F), the blood pressure is 130/84 mm Hg, the pulse is 98/min, and the respiratory rate is 20/min. Chest X-ray reveals calcified hilar lymph nodes which look like an eggshell. This patient is at increased risk for which of the following conditions?
Cardiology US Medical PG Practice Questions and MCQs
Question 661: A 55-year-old man presents to the emergency department for chest pain. He states that the pain started last night and has persisted until this morning. He describes the pain as in his chest and radiating into his back between his scapulae. The patient has a past medical history of alcohol abuse and cocaine abuse. He recently returned from vacation on a transatlantic flight. The patient has smoked 1 pack of cigarettes per day for the past 20 years. His temperature is 99.5°F (37.5°C), blood pressure is 167/118 mmHg, pulse is 120/min, and respirations are 22/min. Physical exam reveals tachycardia and clear air movement bilaterally on cardiopulmonary exam. Which of the following is also likely to be found in this patient?
A. Pulmonary artery thrombus
B. Coronary artery thrombus
C. Elevated lipase
D. Asymmetric blood pressures in the upper extremities (Correct Answer)
E. Coronary artery vasospasm
Explanation: ***Asymmetric blood pressures in the upper extremities***
- The patient's presentation with **sudden-onset, severe, tearing chest pain radiating to the back**, combined with **hypertension** and **tachycardia**, is highly suggestive of an **aortic dissection**. Asymmetric blood pressures are a classic sign.
- Aortic dissection involves a tear in the intima of the aorta, leading to a false lumen that can compress branch arteries, causing **pulse deficits** or **limb ischemia**, resulting in pressure differences.
*Pulmonary artery thrombus*
- While a **transatlantic flight** is a risk factor for **pulmonary embolism (PE)**, the described chest pain is typically pleuritic and not usually severe or radiating to the back in this manner.
- PE often presents with **dyspnea** and **hypoxia**, which are not prominent features described here.
*Coronary artery thrombus*
- **Cocaine abuse**, **smoking**, and **hypertension** are risk factors for **myocardial infarction (MI)** due to **coronary artery thrombosis**. However, MI pain is typically crushing or constricting, and radiation to the back between the scapulae is less common than in dissection.
- The description of **tearing pain** is more characteristic of aortic dissection than MI.
*Elevated lipase*
- The patient's history of **alcohol abuse** and **cocaine abuse** are risk factors for **pancreatitis**, which presents with elevated lipase. However, pancreatitis pain is typically **epigastric** and radiates to the back, but it's usually steady, severe, and often associated with nausea/vomiting, not the tearing quality described.
- The acute, severe, radiating chest pain pattern is not typical for an initial presentation of pancreatitis.
*Coronary artery vasospasm*
- **Cocaine abuse** is a known trigger for **coronary artery vasospasm**, leading to angina or MI, and can cause chest pain.
- However, the pain from vasospasm is usually anginal in quality, often responsive to nitrates, and less likely to present with the severe, tearing, interscapular back pain and hemodynamic instability suggestive of aortic dissection.
Question 662: A 67-year old woman is brought to the emergency department after she lost consciousness while at home. Her daughter was with her at the time and recalls that her mother was complaining of a diffuse headache and nausea about 2 hours before the incident. The daughter says that her mother has not had any recent falls and was found sitting in a chair when she lost consciousness. She has hypertension. Current medications include amlodipine, a daily multivitamin, and acetaminophen. She has smoked 1/2 pack of cigarettes daily for the past 45 years. Her pulse is 92/min, respirations are 10/min, and blood pressure is 158/100 mm Hg. She is disoriented and unable to follow commands. Examination shows nuchal rigidity. She has flexor posturing to painful stimuli. Fundoscopic examination is notable for bilateral vitreous hemorrhages. Laboratory studies are within normal limits. An emergent non-contrast CT scan of the head is obtained and shows a diffuse hemorrhage at the base of the brain that is largest over the left hemisphere. Which of the following is the most likely cause of this patient's symptoms?
A. Intracranial arterial dissection
B. Ruptured saccular aneurysm (Correct Answer)
C. Ruptured mycotic aneurysm
D. Spinal arteriovenous malformation
E. Intracranial arteriovenous malformation
Explanation: ***Ruptured saccular aneurysm***
- The sudden onset of a "thunderclap" headache, **nuchal rigidity**, diffuse hemorrhage at the base of the brain, and **vitreous hemorrhages (Terson syndrome)** are all highly suggestive of a **subarachnoid hemorrhage (SAH)**, most commonly caused by a ruptured saccular aneurysm. Her history of **hypertension and smoking** are significant risk factors for aneurysm formation and rupture.
- The disorientation and flexor posturing indicate severe neurological compromise due to increased **intracranial pressure** and brainstem involvement, consistent with a large SAH.
*Intracranial arterial dissection*
- While an intracranial arterial dissection can cause hemorrhage, it typically presents with neck pain, lower cranial nerve palsies, or ischemic stroke symptoms due to **thromboembolism**, which are not prominent features here.
- The **diffuse hemorrhage at the base of the brain** and bilateral vitreous hemorrhages are more characteristic of a ruptured aneurysm than a dissection.
*Ruptured mycotic aneurysm*
- A mycotic aneurysm results from an **infectious embolus** lodging in an artery, leading to vessel wall weakening and rupture. This would typically be seen in the context of **endocarditis** or other systemic infections, for which there is no evidence in this patient.
- The patient's presentation lacks systemic signs of infection (e.g., fever, new heart murmur, or elevated inflammatory markers) that would point to an infectious etiology.
*Spinal arteriovenous malformation*
- A spinal arteriovenous malformation (AVM) would present with **spinal cord symptoms** such as back pain, weakness, sensory deficits, or bladder/bowel dysfunction, not primarily with a diffuse intracranial hemorrhage or severe headache.
- While it could theoretically cause a hemorrhage, the clinical presentation and CT findings are unequivocally localized to the **brain**, making a spinal origin unlikely.
*Intracranial arteriovenous malformation*
- An intracranial AVM can cause **intracerebral hemorrhage** or, less commonly, subarachnoid hemorrhage, but the hemorrhages tend to be more localized within the brain parenchyma or along the AVM itself.
- Though an AVM could be a differential, the classic presentation including **thunderclap headache**, Terson syndrome, and diffuse basilar hemorrhage is a more classic presentation of a **ruptured saccular aneurysm**.
Question 663: A 33-year-old woman comes to the physician because of left leg pain and swelling for 1 day. She has had two miscarriages but otherwise has no history of serious illness. Physical examination shows stiff, swollen finger joints. The left calf circumference is larger than the right and there is a palpable cord in the left popliteal fossa. Laboratory studies show a prothrombin time of 12 seconds and an activated partial thromboplastin time of 51 seconds. Which of the following is most likely to confirm the diagnosis?
A. Anti-β2 glycoprotein antibodies (Correct Answer)
B. Anti-ribonucleoprotein antibodies
C. Anti-nuclear antibodies
D. Anti-cyclical citrullinated peptide antibodies
E. Anti-synthetase antibodies
Explanation: ***Anti-β2 glycoprotein antibodies***
- This patient presents with recurrent miscarriages, thrombotic events (left leg pain, swelling, palpable cord suggesting **deep vein thrombosis**), and elevated **aPTT**, highly suggestive of **antiphospholipid syndrome (APS)**.
- **Anti-β2 glycoprotein I antibodies** are one of the key diagnostic criteria for APS, along with **lupus anticoagulant** and **anticardiolipin antibodies**.
*Anti-ribonucleoprotein antibodies*
- These antibodies are predominantly associated with **mixed connective tissue disease (MCTD)** and occasionally with lupus or scleroderma.
- While there are joint symptoms, the thrombotic events and recurrent miscarriages are not typical primary features of MCTD.
*Anti-nuclear antibodies*
- **ANA** is a screening test for various autoimmune diseases, particularly **systemic lupus erythematosus (SLE)**. A positive ANA in isolation would not confirm APS.
- While APS can occur secondary to SLE, the primary clinical picture directly points to APS, and specific APS antibodies are needed for diagnosis.
*Anti-cyclical citrullinated peptide antibodies*
- **Anti-CCP antibodies** are highly specific for **rheumatoid arthritis (RA)**.
- While the patient has stiff, swollen finger joints, the presence of DVT and recurrent miscarriages are not features of RA.
*Anti-synthetase antibodies*
- These antibodies are associated with **inflammatory myopathies**, such as **polymyositis** and **dermatomyositis**, especially those with **interstitial lung disease** and **"mechanic's hands."**
- The clinical presentation of thrombosis and miscarriages does not align with the typical features of anti-synthetase syndrome.
Question 664: A 57-year-old man comes to the physician two weeks after a blood pressure of 160/92 mm Hg was measured at a routine health maintenance examination. Subsequent home blood pressure measurements since the last visit have been: 159/98 mm Hg, 161/102 mm Hg, and 152/95 mm Hg. Over the past 3 years, the patient has had a 10-kg (22-lb) weight gain. He has type 2 diabetes mellitus. He does not follow any specific diet; he usually eats sandwiches at work and fried chicken or burger for dinner. He says that he has been struggling with a stressful project at work recently. His mother was diagnosed with hypertension at the age of 45. The patient's only medication is metformin. His pulse is 82/min, and blood pressure now is 158/98 mm Hg. The patient is 178 cm (5 ft 10 in) tall and weighs 133 kg (293 lb); BMI is 42 kg/m2. Physical examination shows no other abnormalities except for significant central obesity. Fasting serum studies show:
Total cholesterol 220 mg/dL
HDL-cholesterol 25 mg/dL
Triglycerides 198 mg/dL
Glucose 120 mg/dL
Which of the following is the most important factor in the development of this patient's condition?
A. Increased dietary salt intake
B. Resistance to insulin (Correct Answer)
C. Accumulation of fat in visceral tissue
D. Release of proinflammatory cytokines
E. Elevation of blood lipids
Explanation: ***Resistance to insulin***
- **Insulin resistance** is a key component of **metabolic syndrome**, which includes **central obesity**, **hypertension**, **dyslipidemia**, and **type 2 diabetes mellitus**, all present in this patient.
- It leads to **compensatory hyperinsulinemia**, which contributes to hypertension by increasing **sodium reabsorption**, sympathetic nervous system activity, and vascular smooth muscle proliferation.
*Increased dietary salt intake*
- While **high dietary salt intake** can contribute to **hypertension**, the patient's diet history (sandwiches, fried chicken, burgers) primarily suggests high fat and calorie intake, not explicitly high sodium.
- The patient's **obesity** and **diabetes** point more strongly towards underlying **insulin resistance** as the primary driver of hypertension.
*Accumulation of fat in visceral tissue*
- **Visceral obesity** is a strong risk factor for hypertension and is evident in this patient (BMI 42 kg/m2, central obesity).
- However, **visceral fat accumulation** is itself a major contributor to **insulin resistance**, making insulin resistance the more fundamental pathophysiological factor.
*Release of proinflammatory cytokines*
- **Chronic inflammation** and the release of **proinflammatory cytokines** from adipose tissue are associated with obesity and insulin resistance.
- While contributing to cardiovascular risk, these cytokines are part of the downstream effects of **insulin resistance** and obesity, not the primary initiating factor.
*Elevation of blood lipids*
- The patient has **dyslipidemia** (high total cholesterol, low HDL, high triglycerides), which is a common comorbidity of metabolic syndrome and increases cardiovascular risk.
- However, **dyslipidemia** is often a consequence of **insulin resistance**, which impairs lipid metabolism, rather than the primary cause of the patient's hypertension.
Question 665: A 67-year-old man is brought to the emergency department because of increasing shortness of breath that began while playing outdoors with his grandson. He has a history of asthma but does not take any medications for it. On arrival, he is alert and oriented. He is out of breath and unable to finish his sentences. His pulse is 130/min, respirations are 23/min and labored, and blood pressure is 110/70 mm Hg. Physical examination shows nasal flaring and sternocleidomastoid muscle use. Pulmonary exam shows poor air movement bilaterally but no wheezing. Cardiac examination shows no abnormalities. Oxygen is administered via non-rebreather mask. He is given three albuterol nebulizer treatments, inhaled ipratropium, and intravenous methylprednisolone. The patient is confused and disoriented. Arterial blood gas analysis shows:
pH 7.34
Pco2 44 mm Hg
Po2 54 mm Hg
O2 saturation 87%
Which of the following is the most appropriate next step in management?
A. Flexible bronchoscopy
B. Intravenous magnesium sulfate therapy
C. Endotracheal intubation (Correct Answer)
D. Continuous albuterol nebulizer therapy
E. Intravenous theophylline therapy
Explanation: ***Endotracheal intubation***
- The patient's **worsening mental status** (confused and disoriented after initial treatment) and persistent **hypoxemia** (PO2 54 mmHg, O2 sat 87%) despite aggressive therapy indicate impending **respiratory failure** and the need for immediate advanced airway management.
- The **normal PCO2** (44 mmHg) in a patient with severe asthma exacerbation is concerning, as it suggests the patient is tiring and unable to maintain adequate ventilation, which can quickly lead to hypercapnia and respiratory arrest.
*Flexible bronchoscopy*
- This procedure is typically used for **diagnostic purposes** (e.g., investigating foreign body aspiration, airway obstruction, or pneumonia) and is not an immediate life-saving intervention for acute respiratory failure.
- It would delay critical airway management and ventilation in a patient with rapidly deteriorating status.
*Intravenous magnesium sulfate therapy*
- **Magnesium sulfate** is a bronchodilator that can be used as an **adjunctive therapy** in severe asthma exacerbations, particularly in patients not responding to initial bronchodilator treatment.
- However, it is not the primary intervention when a patient is showing signs of impending respiratory arrest and requires immediate airway protection and ventilatory support.
*Continuous albuterol nebulizer therapy*
- The patient has already received three albuterol nebulizer treatments, and while continuous albuterol can be beneficial in severe asthma, the patient's **deteriorating mental status** and **persistent hypoxemia** indicate he needs more aggressive respiratory support than just further bronchodilator therapy.
- The immediate priority is to secure the airway and ensure adequate oxygenation and ventilation.
*Intravenous theophylline therapy*
- **Theophylline** is a bronchodilator with a narrow therapeutic window and significant potential for toxicity, making it a **third-line agent** for severe asthma that is refractory to standard treatments.
- Its slow onset of action and potential side effects make it inappropriate as an initial or immediate intervention in a patient with acute respiratory failure.
Question 666: A 65-year-old woman presents to her physician with a persistent and debilitating cough which began 3 weeks ago, and chest pain accompanied by shortness of breath for the past week. Past medical history is significant for breast carcinoma 10 years ago treated with mastectomy, chemotherapy and radiation, a hospitalization a month ago for pneumonia that was treated with antibiotics, hypertension, and diabetes mellitus. Medications include chlorthalidone and metformin. She does not smoke but her husband has been smoking 3 packs a day for 30 years. Today her respiratory rate is 20/min and the blood pressure is 150/90 mm Hg. Serum Na is 140 mmol/L, serum K is 3.8 mmol/L and serum Ca is 12.2 mg/dL. A chest X-ray (shown in image) is performed. Which of the following is the most likely diagnosis?
A. Squamous cell carcinoma lung (Correct Answer)
B. Small cell carcinoma lung
C. Bacterial pneumonia
D. Tuberculosis
E. Viral pneumonia
Explanation: ***Squamous cell carcinoma lung***
- The patient's history of a chronic cough, chest pain, and shortness of breath, combined with **hypercalcemia** (serum Ca 12.2 mg/dL), is highly suggestive of **squamous cell carcinoma of the lung**, which often produces parathyroid hormone-related protein (PTHrP).
- The chest X-ray shows multiple **nodular opacities**, some of which appear cavitary, consistent with centrally located squamous cell carcinoma, especially in a patient with significant **secondhand smoke exposure**.
*Small cell carcinoma lung*
- While small cell carcinoma can present with similar respiratory symptoms, it typically causes **hyponatremia** due to SIADH, not hypercalcemia.
- It often presents as a **central mass** with hilar lymphadenopathy but cavitary lesions are less common, and it is strongly associated with **smoking**.
*Bacterial pneumonia*
- Pneumonia typically presents with acute onset of fever, cough with productive sputum, and localized infiltrates on chest X-ray, which resolve with antibiotics. This patient's symptoms are persistent despite recent antibiotic treatment for pneumonia.
- The **multiple cavitary lesions** and **hypercalcemia** are not typical features of bacterial pneumonia.
*Tuberculosis*
- Although tuberculosis can cause chronic cough and cavitary lesions, patients often present with **night sweats**, weight loss, and hemoptysis, and hypercalcemia is rare.
- The prior breast cancer and prolonged secondhand smoke exposure make lung carcinoma a more likely diagnosis.
*Viral pneumonia*
- Viral pneumonia usually presents with acute symptoms like fever, myalgias, and non-productive cough, and chest X-ray typically shows **diffuse interstitial infiltrates**.
- The patient's persistent, debilitating cough, cavitary lesions, and hypercalcemia are not characteristic of viral pneumonia.
Question 667: A 25-year-old female comes to the physician because of fever and worsening cough for the past 4-days. She has had several episodes of otitis media, sinusitis, and an intermittent cough productive of green sputum for the past 2-years. She has also noticed some streaks of blood in the sputum lately. Her temperature is 38°C (100.4°F). Auscultation of the chest reveals crackles and rhonchi bilaterally. Heart sounds cannot be heard along the left lower chest. A CT scan of the chest reveals bronchiectasis and dextrocardia. Which of the following additional findings is most likely in this patient?
A. Increased sweat chloride levels
B. Defective interleukin-2 receptor gamma chain
C. Decreased immunoglobulin levels
D. NADPH oxidase deficiency
E. Delayed tubal ovum transit (Correct Answer)
Explanation: ***Delayed tubal ovum transit***
- The patient's symptoms (recurrent upper and lower respiratory infections, bronchiectasis, and dextrocardia) are characteristic of **Kartagener syndrome**, a type of **primary ciliary dyskinesia**.
- In Kartagener syndrome, defective cilia throughout the body, including the **fallopian tubes**, lead to impaired ovum transport and often **infertility** in females.
*Increased sweat chloride levels*
- This finding is characteristic of **cystic fibrosis**, a genetic disorder affecting chloride channels.
- While cystic fibrosis can cause recurrent respiratory infections and bronchiectasis, it is not typically associated with **dextrocardia** or situs inversus.
*Defective interleukin-2 receptor gamma chain*
- This defect is associated with **X-linked severe combined immunodeficiency (SCID)**.
- SCID presents with recurrent severe infections early in life due to a profound deficiency in T-lymphocytes and B-lymphocytes, which does not fit the 25-year-old patient's presentation with chronic but non-fatal respiratory issues and structural anomalies like dextrocardia.
*Decreased immunoglobulin levels*
- This suggests a **humoral immunodeficiency**, such as **common variable immunodeficiency (CVID)**.
- While CVID can cause recurrent sinopulmonary infections, it is not associated with **bronchiectasis** in combination with **dextrocardia**, which points more towards a structural or ciliary defect.
*NADPH oxidase deficiency*
- This is the hallmark of **chronic granulomatous disease (CGD)**, a primary immunodeficiency.
- Patients with CGD are prone to recurrent infections with **catalase-positive organisms** and form granulomas, but this condition is not associated with **dextrocardia** or the specific constellation of symptoms seen in this patient.
Question 668: A 12-year-old boy presents with progressive clumsiness and difficulty walking. He walks like a 'drunken-man' and has experienced frequent falls. He was born at term and has gone through normal developmental milestones. His vaccination profile is up to date. He denies fever, chills, nausea, vomiting, chest pain, and shortness of breath. He has no history of alcohol use or illicit drug use. His elder brother experienced the same symptoms. The physical examination reveals normal higher mental functions. His extraocular movements are normal. His speech is mildly dysarthric. His muscle tone and strength in all 4 limbs are normal. His ankle reflexes are absent bilaterally with positive Babinski’s signs. Both vibration and proprioception are absent bilaterally. When he is asked to stand with his eyes closed and with both feet close together, he sways from side to side, unable to stand still. X-ray results show mild scoliosis. Electrocardiogram results show widespread T-wave inversions. His fasting blood glucose level is 143 mg/dL. What is the most likely diagnosis?
A. Charcot-Marie-Tooth disease
B. Myotonic dystrophy
C. Ataxia-telangiectasia
D. Friedreich’s ataxia (Correct Answer)
E. Duchenne muscular dystrophy
Explanation: ***Friedreich's ataxia***
- This diagnosis is strongly supported by the **autosomal recessive inheritance pattern** (elder brother affected), **progressive ataxia** ("drunken-man" walk, clumsiness, frequent falls), **dysarthria**, **absent ankle reflexes**, **positive Babinski's signs**, and loss of **vibration and proprioception**. The additional findings of **scoliosis**, **T-wave inversions** (suggesting hypertrophic cardiomyopathy), and **diabetes mellitus** (fasting blood glucose of 143 mg/dL) are classic features of Friedreich's ataxia.
- The **Romberg sign** (swaying with eyes closed and feet together) indicates a **sensory ataxia**, consistent with dorsal column involvement in Friedreich's ataxia.
*Charcot-Marie-Tooth disease*
- While it can present with gait difficulties and absent reflexes, it is primarily a **peripheral neuropathy** characterized by **distal muscle weakness and atrophy** (e.g., foot drop, "stork-leg" deformity), which are not described in this patient.
- It does not typically involve the brainstem or cerebellum, nor does it commonly present with **Babinski's sign**, **dysarthria**, or the specific cardiac and metabolic abnormalities seen here.
*Myotonic dystrophy*
- This condition is characterized by **myotonia** (delayed muscle relaxation), **progressive muscle weakness**, and multi-system involvement (e.g., cataracts, frontal baldness, endocrine issues).
- While it can manifest with gait difficulties and muscle weakness, the classic neurological findings of **sensory ataxia**, **dysarthria**, **absent ankle reflexes with positive Babinski's signs**, and specific cardiac involvement like T-wave inversions are not typical.
*Ataxia-telangiectasia*
- Key features include **progressive cerebellar ataxia** developing in early childhood, along with **oculocutaneous telangiectasias** (spider veins on eyes and skin), **immunodeficiency**, and increased risk of malignancy.
- Although ataxia is present, the absence of telangiectasias, immunodeficiency, and the specific constellation of sensory deficits, cardiac findings, and diabetes make this less likely.
*Duchenne muscular dystrophy*
- This is an X-linked recessive disorder characterized by **progressive muscle weakness** and **atrophy** predominantly affecting proximal muscles, leading to a **waddling gait**, **Gowers' sign**, and elevated creatine kinase levels.
- It does not typically present with **sensory ataxia**, **dysarthria**, **hyperreflexia (Babinski's sign)**, or the specific cardiac and metabolic (diabetes) manifestations seen in this case.
Question 669: A 36-year-old woman presents to the emergency department with chest discomfort and fatigue. She reports that her symptoms began approximately 1 week ago and are associated with shortness of breath, swelling of her legs, and worsening weakness. She’s been having transitory fevers for about 1 month and denies having similar symptoms in the past. Medical history is significant for systemic lupus erythematosus (SLE) treated with hydroxychloroquine. She had a SLE flare approximately 2 weeks prior to presentation, requiring a short course of prednisone. Physical exam was significant for a pericardial friction rub. An electrocardiogram showed widespread ST-segment elevation and PR depression. After extensive work-up, she was admitted for further evaluation, treatment, and observation. Approximately 2 days after admission she became unresponsive. Her temperature is 100°F (37.8°C), blood pressure is 75/52 mmHg, pulse is 120/min, and respirations are 22/min. Heart sounds are muffled. Which of the following is a clinical finding that will most likely be found in this patient?
A. Warm extremities
B. Pericardial knock
C. Decreased systolic blood pressure by 8 mmHg with inspiration
D. Jugular venous distension (Correct Answer)
E. Unequal blood pressure measurements between both arms
Explanation: ***Jugular venous distension***
- The patient's presentation with **muffled heart sounds**, **hypotension**, and a **pericardial friction rub** points towards **cardiac tamponade**, a medical emergency caused by fluid accumulation in the pericardial sac.
- **Jugular venous distension** is a key component of **Beck's triad** (along with muffled heart sounds and hypotension) and indicates increased right atrial pressure due to restricted ventricular filling.
*Warm extremities*
- **Warm extremities** are more characteristic of **vasodilatory shock** (e.g., septic shock), where peripheral vasodilation leads to increased skin temperature.
- In **cardiac tamponade**, reduced cardiac output typically results in **cool and clammy extremities** due to compensatory peripheral vasoconstriction.
*Pericardial knock*
- A **pericardial knock** is an early diastolic sound often heard in **constrictive pericarditis**, caused by the sudden cessation of ventricular filling.
- While the patient has pericardial involvement, the acute presentation with signs of shock is more consistent with **cardiac tamponade**, rather than chronic constriction.
*Decreased systolic blood pressure by 8 mmHg with inspiration*
- **Pulsus paradoxus** (a decrease in systolic blood pressure of **>10 mmHg with inspiration**) is a hallmark sign of **cardiac tamponade**.
- While this patient likely has pulsus paradoxus, the value of **8 mmHg falls below the diagnostic threshold** of 10 mmHg and would not be considered pathological pulsus paradoxus.
- **Jugular venous distension** is a more reliable and clinically obvious finding in cardiac tamponade.
*Unequal blood pressure measurements between both arms*
- **Unequal blood pressure measurements between the arms** (>10-15 mmHg difference) are characteristic of conditions like **aortic dissection** or **subclavian artery stenosis**.
- This finding is not typically associated with **cardiac tamponade**, which affects global cardiac function.
Question 670: A 54-year-old man presents to the office complaining of recent shortness of breath and fever. He has a history of a chronic cough which is progressively getting worse. His medical history is significant for hypertension and diabetes mellitus, both controlled with medication. He has been working in a sandblasting factory for over 3 decades. His temperature is 37.7°C (99.9°F), the blood pressure is 130/84 mm Hg, the pulse is 98/min, and the respiratory rate is 20/min. Chest X-ray reveals calcified hilar lymph nodes which look like an eggshell. This patient is at increased risk for which of the following conditions?
A. Mesothelioma
B. Chronic obstructive pulmonary disease
C. Pulmonary embolism
D. Adenocarcinoma of the lung
E. Mycobacterium tuberculosis infection (Correct Answer)
Explanation: ***Mycobacterium tuberculosis infection***
- The patient's presentation with a **chronic cough**, **shortness of breath**, and **fever**, coupled with a history of **sandblasting** (suggesting **silicosis** and **eggshell calcifications** on X-ray), places him at a significantly higher risk for **Mycobacterium tuberculosis infection**.
- **Silicosis** impairs macrophage function and predisposes individuals to reactivation of latent tuberculosis or increased susceptibility to new TB infections.
*Mesothelioma*
- **Mesothelioma** is strongly associated with **asbestos exposure**, not typically sandblasting or silica.
- While asbestos exposure can involve some construction-related activities, sandblasting specifically points to **silica exposure**.
*Chronic obstructive pulmonary disease*
- Although the patient's symptoms (chronic cough, dyspnea) could align with **COPD**, the imaging finding of **eggshell calcifications** specifically points to **silicosis**, which has a different primary complication risk, particularly **tuberculosis**.
- No information about smoking history or spirometry results is given to confirm COPD.
*Pulmonary embolism*
- **Pulmonary embolism** typically presents with acute-onset dyspnea, pleuritic chest pain, and sometimes hemoptysis, without the long-standing cough and fever pattern described. The **eggshell calcifications** are not a feature of PE.
- The patient's vital signs are not acutely unstable in a way that would strongly suggest an immediate PE.
*Adenocarcinoma of the lung*
- While **silicosis** can increase the risk of lung cancer, particularly **adenocarcinoma**, the presenting symptoms of fever and the specific finding of **calcified hilar lymph nodes with eggshell calcification** make **tuberculosis** a more immediate concern given the compromised immune status associated with silicosis.
- **Silicosis-related lung cancer** typically develops after many years, and while possible, the acute infectious symptoms point to a more immediate etiology.
