A 65-year-old man comes to the emergency department 1 hour after a loss of consciousness. His wife said he suddenly fainted while she was adjusting his necktie. He regained consciousness within 30 seconds and was fully alert and oriented. He has had two similar episodes in the last year. He has anxiety and takes alprazolam as needed. He smokes half a pack of cigarettes daily and drinks two glasses of wine with dinner each night. His temperature is 37.2°C (98.9°F), pulse is 70/min and regular, respirations are 13/min, blood pressure is 130/82 mm Hg when supine and 122/80 mm Hg while standing. Cardiopulmonary examination shows no abnormalities. Neurologic examination shows no focal findings. A complete blood count shows no abnormalities. Bedside cardiac monitoring shows infrequent premature ventricular contractions and QRS voltage below 5 mm in leads II and III. Which of the following is the most likely diagnosis?
Q482
A 45-year-old man with asthma comes to the physician because of a 1-month history of progressively worsening shortness of breath and cough. He also has a history of chronic sinusitis and foot drop. Current medications include an albuterol inhaler and inhaled corticosteroid. Physical examination shows diffuse wheezing over both lung fields and tender subcutaneous nodules on both elbows. Laboratory studies show a leukocyte count of 23,000/mm3 with 26% eosinophils and a serum creatinine of 1.7 mg/dL. Urine microscopy shows red blood cell casts. Which of the following is the most likely diagnosis in this patient?
Q483
A 57-year-old man comes to the emergency department for the evaluation of worsening fatigue, urinary frequency, and constipation over the past 5 days. He was recently diagnosed with metastatic bladder cancer and is currently awaiting treatment. He has smoked 1 pack of cigarettes daily for 35 years. Physical examination shows dry mucous membranes and diffuse abdominal tenderness. An ECG shows a shortened QT interval. Which of the following sets of serum findings is most likely in this patient?
$$$ Calcium %%% Phosphorus %%% Parathyroid hormone %%% 1,25-dihydroxyvitamin D $$$
Q484
A 62-year-old man presents to the emergency department with hematuria and hemoptysis that started in the morning. He notes that he has had frequent lung infections throughout his adult life, the most recent being 2 weeks ago. He also mentions that he has had hematuria twice before but never as severe as he is having currently. His medical history is otherwise non-significant, and his only medication is acetaminophen as needed. His blood pressure is 136/92 mm Hg, heart rate is 86/min, respiratory rate is 16/min, and temperature is 37.0°C (98.6°F). Chest radiography shows a resolving right middle lobe airspace opacity. His initial laboratory tests are notable for elevated erythrocyte sedimentation rate and C-reactive protein level. While in the examination room, the patient develops a spontaneous nosebleed. What is the most likely diagnosis?
Q485
A 75-year-old man is brought to the emergency department by his son. He is suffering from left-sided weakness. The symptoms started 2 hours ago with sudden left-sided weakness. The patient is a known hypertensive, who is inconsistently compliant with his 2 antihypertensive medications and a heavy smoker, with a 40 pack year history. Physical examination shows an elderly male in mild distress. The vital signs include: blood pressure 140/95 mm Hg, pulse 89/min and SpO2 98% on room air. Neurological examination shows left-sided hemiparesis, with no sensory, cognitive, or brain stem abnormalities. A CT scan of the head without IV contrast shows a right-sided ischemic infarct. What other finding is most likely to develop in this patient as his condition progresses?
Q486
A 38-year-old woman presents with generalized weakness and dizziness for the past 3 weeks. Past medical history is significant for systemic lupus erythematosus diagnosed 15 years ago, for which she takes hydroxychloroquine and methotrexate. No significant family history. Her vital signs include: temperature 37.1°C (98.7°F), blood pressure 122/65 mm Hg, pulse 100/min. Physical examination reveals generalized pallor; sclera are icteric. Her laboratory results are significant for the following:
Hemoglobin 7.3 g/dL
Mean corpuscular hemoglobin (MCH) 45 pg/cell
Reticulocyte count 6%
Direct antiglobulin test Positive
Peripheral blood smear Spherocytes
Which of the following best represents the most likely cause of this patient's condition?
Q487
A 50-year-old man presents to the urgent care clinic for 3 hours of worsening cough, shortness of breath, and dyspnea. He works as a long-haul truck driver, and he informs you that he recently returned to the west coast from a trip to Arkansas. His medical history is significant for gout, hypertension, hypercholesterolemia, diabetes mellitus type 2, chronic obstructive pulmonary disease (COPD), and mild intellectual disability. He currently smokes 1 pack of cigarettes/day, drinks a 6-pack of beer/day, and he endorses a past history of injection drug use but currently denies any illicit drug use. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 87/min, and respiratory rate 23/min. His physical examination shows mild, bilateral, coarse rhonchi, but otherwise clear lungs on auscultation, grade 2/6 holosystolic murmur, and a benign abdominal physical examination. He states that he ran out of his albuterol inhaler 6 days ago and has been meaning to follow-up with his primary care physician (PCP) for a refill. Complete blood count (CBC) and complete metabolic panel are within normal limits. He also has a D-dimer result within normal limits. Which of the following is the most appropriate next step in evaluation?
Q488
A 38-year-old man presents to his physician for difficulty swallowing for 2 months. He describes food getting stuck down his windpipe and has been feeling very anxious around meal time because he is thinking that he may have esophageal cancer. He has had an influenza-like infection that lasted about 6 weeks in the past 3 months which exacerbated his asthma attacks. He used his puffers to relieve his symptoms and did not seek medical treatment. He is otherwise healthy. On examination, his blood pressure is 118/75 mm Hg, respirations are 17/min, pulse is 78/min, and temperature is 36.7°C (98.1°F). There is no evidence of enlarged lymph nodes or a sore throat. On palpation, the thyroid gland is enlarged and tender. He is a non-smoker with a BMI of 25 kg/m2. He has not used any medications recently. Which of the following is the most likely diagnosis?
Q489
A 62-year-old female is brought to the hospital by her daughter. Six hours ago, she was at a wedding giving a speech when she suddenly experienced difficulty finding words and a right facial droop. She denies any extremity weakness, paresthesias, or sensory deficits. She has a history of hypertension and type 2 diabetes. She takes hydrochlorothiazide and insulin. Her last HbA1c was 10.3% four months ago. Vital signs are within normal limits. There is right lower facial droop on exam, but she is able to raise her eyebrows symmetrically. Speech is slow and slightly dysarthric. She has difficulty naming some objects. Her exam is otherwise unremarkable. Brain MRI shows a 3.2-cm infarct in the left frontal region. The patient is admitted to the neurology service for further management. On hospital day three her laboratory results show the following:
Serum
Na+ 131 mEq/L
Osmolality 265 mOsmol/kg H2O
Urine
Na+ 46 mEq/L
Osmolality 332 mOsmol/kg H2O
This patient is most likely to have which of the following additional findings?
Q490
A 67-year-old man presents to the emergency department for a headache. The patient states his symptoms started thirty minutes ago. He states he experienced a sudden and severe headache while painting his house, causing him to fall off the ladder and hit his head. He has also experienced two episodes of vomiting and difficulty walking since the fall. The patient has a past medical history of hypertension, obesity, and atrial fibrillation. His current medications include lisinopril, rivaroxaban, atorvastatin, and metformin. His temperature is 99.5°F (37.5°C), blood pressure is 150/105 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 98% on room air. On physical exam, the patient localizes his headache to the back of his head. Cardiac exam reveals a normal rate and rhythm. Pulmonary exam reveals minor bibasilar crackles. Neurological exam is notable for minor weakness of the muscles of facial expression. Examination of cranial nerve three reveals a notable nystagmus. Heel to shin exam is abnormal bilaterally. The patient's gait is notably ataxic. A non-contrast CT scan of the head is currently pending. Which of the following is the most likely diagnosis?
Cardiology US Medical PG Practice Questions and MCQs
Question 481: A 65-year-old man comes to the emergency department 1 hour after a loss of consciousness. His wife said he suddenly fainted while she was adjusting his necktie. He regained consciousness within 30 seconds and was fully alert and oriented. He has had two similar episodes in the last year. He has anxiety and takes alprazolam as needed. He smokes half a pack of cigarettes daily and drinks two glasses of wine with dinner each night. His temperature is 37.2°C (98.9°F), pulse is 70/min and regular, respirations are 13/min, blood pressure is 130/82 mm Hg when supine and 122/80 mm Hg while standing. Cardiopulmonary examination shows no abnormalities. Neurologic examination shows no focal findings. A complete blood count shows no abnormalities. Bedside cardiac monitoring shows infrequent premature ventricular contractions and QRS voltage below 5 mm in leads II and III. Which of the following is the most likely diagnosis?
A. Carotid sinus hypersensitivity (Correct Answer)
B. Cardiac arrhythmia
C. Panic attack
D. Structural cardiac abnormality
E. Orthostatic syncope
Explanation: ***Carotid sinus hypersensitivity***
- The sudden loss of consciousness after **adjusting a necktie** (pressure on the carotid sinus) is highly suggestive of carotid sinus hypersensitivity.
- Repeated episodes of **syncope triggered by neck manipulation** in an otherwise healthy individual further support this diagnosis.
*Cardiac arrhythmia*
- While **infrequent PVCs** are noted, there are no findings to suggest a significant arrhythmia causing syncope (e.g., prolonged asystole, sustained ventricular tachycardia, or severe bradycardia).
- The **normal vital signs** and prompt recovery with full alertness point away from a severe cardiac event.
*Panic attack*
- Although the patient has anxiety and takes alprazolam, a panic attack is less likely given the **clear physical trigger** (necktie adjustment) and the **absence of typical panic symptoms** like hyperventilation, chest pain, or fear of dying during the syncope episodes.
- Syncope in panic attacks is usually psychogenic and not directly caused by external physical stimulation.
*Structural cardiac abnormality*
- The **cardiopulmonary examination is normal**, and the **low QRS voltage** alone is not specific enough to diagnose a structural abnormality causing syncope in this context.
- The clear trigger of neck pressure makes a structural cardiac cause less probable as the primary etiology.
*Orthostatic syncope*
- The patient's **blood pressure shows only a slight drop** upon standing, which is not indicative of orthostatic hypotension significant enough to cause syncope.
- The clear trigger of **neck pressure** rather than a change in position makes orthostatic syncope unlikely.
Question 482: A 45-year-old man with asthma comes to the physician because of a 1-month history of progressively worsening shortness of breath and cough. He also has a history of chronic sinusitis and foot drop. Current medications include an albuterol inhaler and inhaled corticosteroid. Physical examination shows diffuse wheezing over both lung fields and tender subcutaneous nodules on both elbows. Laboratory studies show a leukocyte count of 23,000/mm3 with 26% eosinophils and a serum creatinine of 1.7 mg/dL. Urine microscopy shows red blood cell casts. Which of the following is the most likely diagnosis in this patient?
A. Granulomatosis with polyangiitis
B. Polyarteritis nodosa
C. Eosinophilic granulomatosis with polyangiitis (Correct Answer)
D. Microscopic polyangiitis
E. Immunoglobulin A vasculitis
Explanation: ***Eosinophilic granulomatosis with polyangiitis (EGPA)***
- The patient presents with **asthma**, **chronic sinusitis**, **eosinophilia** (26%), and symptoms of vasculitis including **foot drop** (neuropathy), **renal impairment** (elevated creatinine, RBC casts), and **subcutaneous nodules**. This constellation is highly characteristic of EGPA (formerly Churg-Strauss syndrome).
- EGPA is a **small-to-medium vessel vasculitis** defined by **asthma**, **eosinophilia**, and **granulomatous inflammation**.
*Granulomatosis with polyangiitis (GPA)*
- GPA typically involves the **upper and lower respiratory tracts** and **kidneys**, often presenting with chronic sinusitis, lung nodules, and glomerulonephritis.
- While GPA can cause renal impairment and neuropathy, it is not primarily characterized by **asthma** and profound **eosinophilia**, which are key features in this patient.
*Polyarteritis nodosa (PAN)*
- PAN is a **necrotizing vasculitis of medium-sized arteries** that typically affects the kidneys, peripheral nerves, GI tract, and skin.
- PAN is not associated with **asthma** or significant **eosinophilia**, and it typically **spares the lungs**.
*Microscopic polyangiitis (MPA)*
- MPA is a **small-vessel vasculitis** primarily affecting the kidneys and lungs, a common cause of **pulmonary-renal syndrome**.
- While MPA can cause renal failure, and sometimes pulmonary symptoms, it does not typically present with **asthma** or marked **eosinophilia**.
*Immunoglobulin A vasculitis (IgAV)*
- IgAV, also known as Henoch-Schönlein purpura, is characterized by classic triad of **palpable purpura**, **arthralgia**, and **abdominal pain**, and frequently involves the kidneys.
- IgAV primarily affects **small vessels** and is not associated with **asthma**, **eosinophilia**, or the specific neurological and skin manifestations seen in this patient.
Question 483: A 57-year-old man comes to the emergency department for the evaluation of worsening fatigue, urinary frequency, and constipation over the past 5 days. He was recently diagnosed with metastatic bladder cancer and is currently awaiting treatment. He has smoked 1 pack of cigarettes daily for 35 years. Physical examination shows dry mucous membranes and diffuse abdominal tenderness. An ECG shows a shortened QT interval. Which of the following sets of serum findings is most likely in this patient?
$$$ Calcium %%% Phosphorus %%% Parathyroid hormone %%% 1,25-dihydroxyvitamin D $$$
A. ↑ ↓ ↓ ↓ (Correct Answer)
B. ↑ ↑ ↓ ↑
C. ↑ ↑ ↑ ↓
D. ↑ ↓ ↑ ↑
E. ↓ ↑ ↑ ↓
Explanation: ***↑ ↓ ↓ ↓***
- This pattern of **elevated calcium**, **low phosphorus**, **low parathyroid hormone (PTH)**, and **low 1,25-dihydroxyvitamin D** is characteristic of **humoral hypercalcemia of malignancy (HHM)**. Malignant cells, particularly those from bladder cancer, can secrete **parathyroid hormone-related peptide (PTHrP)**, mimicking PTH, leading to increased bone resorption and renal calcium reabsorption, while suppressing endogenous PTH and indirectly leading to low 1,25-dihydroxyvitamin D synthesis.
- The patient's symptoms of fatigue, constipation, urinary frequency, and signs like dry mucous membranes and a shortened QT interval on ECG are all consistent with **hypercalcemia**.
*↑ ↑ ↓ ↑*
- This pattern suggests **hypercalcemia** with **elevated phosphorus** and **elevated 1,25-dihydroxyvitamin D**, which is inconsistent with HHM. Elevated phosphorus is more commonly seen in conditions like **renal failure** or **tumor lysis syndrome**, neither of which are indicated here.
- Elevated 1,25-dihydroxyvitamin D is typically seen in **granulomatous diseases** (e.g., sarcoidosis) or **lymphomas** causing hypercalcemia, not bladder carcinoma.
*↑ ↑ ↑ ↓*
- This profile indicates **hypercalcemia**, **elevated phosphorus**, and **elevated PTH**, which is consistent with **primary hyperparathyroidism**. However, primary hyperparathyroidism typically presents with inappropriately elevated PTH for the level of hypercalcemia, and it's less likely to develop acute, severe hypercalcemia with malignancy unless concurrent.
- The patient's presentation with advanced bladder cancer makes HHM a more likely cause of hypercalcemia than primary hyperparathyroidism.
*↑ ↓ ↑ ↑*
- This constellation, with **elevated calcium**, **low phosphorus**, and **elevated PTH**, is classic for **primary hyperparathyroidism**. In this condition, inappropriately high PTH levels cause increased bone resorption, renal calcium reabsorption, and renal phosphate excretion, leading to hypophosphatemia.
- While primary hyperparathyroidism causes hypercalcemia, the clinical context of advanced metastatic bladder cancer makes HHM a much more probable diagnosis in this patient, and PTH would be suppressed in HHM due to PTHrP mimicking its effects.
*↓ ↑ ↑ ↓*
- This pattern describes **hypocalcemia** (low calcium) with **elevated phosphorus** and **elevated PTH**. This is the hallmark of **secondary hyperparathyroidism**, often seen in **chronic kidney disease**, where low calcium and high phosphorus stimulate PTH release.
- The patient in the vignette presents with symptoms of hypercalcemia, not hypocalcemia, making this option inconsistent with the clinical picture.
Question 484: A 62-year-old man presents to the emergency department with hematuria and hemoptysis that started in the morning. He notes that he has had frequent lung infections throughout his adult life, the most recent being 2 weeks ago. He also mentions that he has had hematuria twice before but never as severe as he is having currently. His medical history is otherwise non-significant, and his only medication is acetaminophen as needed. His blood pressure is 136/92 mm Hg, heart rate is 86/min, respiratory rate is 16/min, and temperature is 37.0°C (98.6°F). Chest radiography shows a resolving right middle lobe airspace opacity. His initial laboratory tests are notable for elevated erythrocyte sedimentation rate and C-reactive protein level. While in the examination room, the patient develops a spontaneous nosebleed. What is the most likely diagnosis?
A. Goodpasture syndrome
B. IgA nephropathy
C. Minimal change disease
D. Post-streptococcal glomerulonephritis
E. Granulomatosis with polyangiitis (Correct Answer)
Explanation: ***Granulomatosis with polyangiitis***
- This patient presents with a **triad of upper airway (nosebleed), lower airway (hemoptysis, recurrent lung infections), and renal involvement (hematuria)**, which is classic for granulomatosis with polyangiitis (GPA), a form of ANCA-associated vasculitis.
- The elevated **ESR and CRP** indicate systemic inflammation, which is common in vasculitic conditions.
*Goodpasture syndrome*
- Characterized by **glomerulonephritis and pulmonary hemorrhage (hemoptysis)**, but typically does not involve the upper airways (e.g., nosebleeds).
- Diagnosis is confirmed by the presence of **anti-glomerular basement membrane antibodies**, which often presents more acutely.
*IgA nephropathy*
- Often presents with **recurrent episodes of gross hematuria**, frequently following an upper respiratory tract infection.
- While it involves the kidneys, it **does not typically cause pulmonary or upper airway symptoms** such as hemoptysis or recurrent lung opacities.
*Minimal change disease*
- Characterized by **nephrotic syndrome (proteinuria, hypoalbuminemia, edema)** and rarely presents with hematuria.
- **Does not cause pulmonary or upper airway manifestations** like hemoptysis or nosebleeds.
*Post-streptococcal glomerulonephritis*
- Typically occurs **1-3 weeks after a streptococcal infection** and presents with acute nephritic syndrome (hematuria, proteinuria, edema, hypertension).
- **Does not involve recurrent lung infections or hemoptysis** and is less likely in an adult with recurrent hematuria episodes.
Question 485: A 75-year-old man is brought to the emergency department by his son. He is suffering from left-sided weakness. The symptoms started 2 hours ago with sudden left-sided weakness. The patient is a known hypertensive, who is inconsistently compliant with his 2 antihypertensive medications and a heavy smoker, with a 40 pack year history. Physical examination shows an elderly male in mild distress. The vital signs include: blood pressure 140/95 mm Hg, pulse 89/min and SpO2 98% on room air. Neurological examination shows left-sided hemiparesis, with no sensory, cognitive, or brain stem abnormalities. A CT scan of the head without IV contrast shows a right-sided ischemic infarct. What other finding is most likely to develop in this patient as his condition progresses?
A. Loss of deep tendon reflexes
B. Positive Babinski sign (Correct Answer)
C. Fasciculations
D. Flaccid paresis
E. Muscle atrophy
Explanation: ***Positive Babinski sign***
- The patient has an **acute ischemic stroke** affecting the **right cerebral hemisphere**, leading to left-sided hemiparesis.
- As the initial **flaccid paralysis** and **spinal shock** phase resolves, **upper motor neuron (UMN) signs** such as spasticity, hyperreflexia, and a positive Babinski sign typically emerge due to damage to the corticospinal tract.
*Loss of deep tendon reflexes*
- This is characteristic of **lower motor neuron (LMN) lesions** or the initial acute phase of an upper motor neuron (UMN) lesion (spinal shock), which is usually transient.
- In a progressive UMN lesion following stroke, **deep tendon reflexes** are expected to become **hyperactive**, not lost.
*Fasciculations*
- **Fasciculations** are spontaneous, visible twitchings of a bundle of muscle fibers and are a hallmark of **lower motor neuron (LMN) pathology**.
- They are not typically seen in **upper motor neuron (UMN) lesions** like an ischemic stroke.
*Flaccid paresis*
- **Flaccid paresis** describes muscle weakness with reduced muscle tone, often seen in the acute phase of a stroke due to **spinal shock**.
- However, as the condition progresses and spinal shock resolves, the **flaccid paresis** will typically evolve into **spastic paresis** due to upper motor neuron damage.
*Muscle atrophy*
- **Muscle atrophy** can occur due to disuse after a stroke, but it is a **late complication** and is not a primary neurological sign that *most likely develops* acutely as the condition progresses.
- Significant **neurogenic atrophy** with severe fasciculations is characteristic of **lower motor neuron lesions**.
Question 486: A 38-year-old woman presents with generalized weakness and dizziness for the past 3 weeks. Past medical history is significant for systemic lupus erythematosus diagnosed 15 years ago, for which she takes hydroxychloroquine and methotrexate. No significant family history. Her vital signs include: temperature 37.1°C (98.7°F), blood pressure 122/65 mm Hg, pulse 100/min. Physical examination reveals generalized pallor; sclera are icteric. Her laboratory results are significant for the following:
Hemoglobin 7.3 g/dL
Mean corpuscular hemoglobin (MCH) 45 pg/cell
Reticulocyte count 6%
Direct antiglobulin test Positive
Peripheral blood smear Spherocytes
Which of the following best represents the most likely cause of this patient's condition?
A. Methotrexate side effect
B. Chronic inflammation
C. Red cell membrane defect
D. IgM-mediated hemolysis
E. IgG-mediated hemolysis (Correct Answer)
Explanation: ***IgG-mediated hemolysis***
- The combination of **anemia**, **reticulocytosis**, **spherocytes** on peripheral smear, **icteric sclera**, and a **positive direct antiglobulin test (DAT)** indicates **autoimmune hemolytic anemia (AIHA)**.
- Given the patient's history of **systemic lupus erythematosus (SLE)**, AIHA is a common complication, and the presence of spherocytes and a positive DAT strongly points towards **IgG-mediated (warm) AIHA**.
*Methotrexate side effect*
- While methotrexate can cause **bone marrow suppression** leading to **anemia**, it typically presents as **macrocytic anemia** (high MCV) with **low reticulocyte count**, not the **hemolytic picture** (high reticulocyte count, spherocytes, icterus) seen here.
- Methotrexate-induced anemia is usually not associated with a **positive DAT** or **spherocytosis**.
*Chronic inflammation*
- **Anemia of chronic disease (ACD)** due to chronic inflammation (e.g., SLE) typically causes **normocytic or microcytic anemia** with a **low reticulocyte count**.
- It does not explain the **hemolytic features** such as **icterus**, **spherocytes**, or the **positive DAT**.
*Red cell membrane defect*
- **Red cell membrane defects** (e.g., **hereditary spherocytosis**) can cause hemolytic anemia with spherocytes, but the **positive DAT** points to an **immune-mediated cause** rather than an intrinsic red cell defect.
- These conditions are typically **congenital** and would not present with an acute onset related to SLE.
*IgM-mediated hemolysis*
- **IgM-mediated hemolysis** (cold agglutinin disease) typically presents with **agglutination** on the peripheral smear, and often has characteristic involvement in **cold temperatures**.
- While it can cause a **positive DAT**, the presence of **spherocytes** is more characteristic of **IgG-mediated warm AIHA**, which is common in SLE.
Question 487: A 50-year-old man presents to the urgent care clinic for 3 hours of worsening cough, shortness of breath, and dyspnea. He works as a long-haul truck driver, and he informs you that he recently returned to the west coast from a trip to Arkansas. His medical history is significant for gout, hypertension, hypercholesterolemia, diabetes mellitus type 2, chronic obstructive pulmonary disease (COPD), and mild intellectual disability. He currently smokes 1 pack of cigarettes/day, drinks a 6-pack of beer/day, and he endorses a past history of injection drug use but currently denies any illicit drug use. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 87/min, and respiratory rate 23/min. His physical examination shows mild, bilateral, coarse rhonchi, but otherwise clear lungs on auscultation, grade 2/6 holosystolic murmur, and a benign abdominal physical examination. He states that he ran out of his albuterol inhaler 6 days ago and has been meaning to follow-up with his primary care physician (PCP) for a refill. Complete blood count (CBC) and complete metabolic panel are within normal limits. He also has a D-dimer result within normal limits. Which of the following is the most appropriate next step in evaluation?
A. Chest computed tomography (CT) with contrast
B. Chest radiographs (Correct Answer)
C. Pulmonary function tests
D. Sputum gram stain and culture
E. Arterial blood gas
Explanation: ***Chest radiographs***
- A **chest X-ray** is the most appropriate initial imaging study for evaluating acute respiratory symptoms in a patient with a history of COPD and recent exacerbating factors (running out of albuterol). It can help identify common causes like **pneumonia**, **pneumothorax**, or **acute exacerbation of COPD**.
- The patient's presentation with worsening cough, shortness of breath, and dyspnea, particularly in the context of running out of his albuterol inhaler, suggests a primary pulmonary issue that a chest X-ray can quickly assess.
*Chest computed tomography (CT) with contrast*
- A **chest CT with contrast** is more detailed but not the initial diagnostic study in this scenario, especially with a normal D-dimer ruling out pulmonary embolism as a high probability.
- It exposes the patient to **higher radiation** and risks associated with contrast, making it less suitable as a first-line investigation unless the chest X-ray is inconclusive or more specific findings are suspected.
*Pulmonary function tests*
- **Pulmonary function tests (PFTs)** are used to diagnose and monitor chronic lung conditions like COPD, but they are generally not performed in an acute urgent care setting for patients presenting with acute respiratory distress.
- PFTs require patient cooperation and are designed to assess baseline lung function, not to identify the **acute cause** of respiratory decompensation.
*Sputum gram stain and culture*
- A **sputum gram stain and culture** might be considered if there's strong suspicion of a bacterial infection (e.g., fever, purulent sputum), but the patient's current symptoms are more aligned with a COPD exacerbation or other acute pulmonary issue.
- Without clear signs of bacterial infection, this test is **not the most immediate or appropriate first step** in evaluating acute dyspnea, as it requires time for results and may delay more crucial diagnostic steps.
*Arterial blood gas*
- An **arterial blood gas (ABG)** can provide information on oxygenation, ventilation, and acid-base status, which is useful in assessing the severity of respiratory failure.
- However, it's typically ordered after an initial clinical and imaging assessment to quantify the physiological impact of the respiratory distress, rather than being the **very first diagnostic step** to identify the cause.
Question 488: A 38-year-old man presents to his physician for difficulty swallowing for 2 months. He describes food getting stuck down his windpipe and has been feeling very anxious around meal time because he is thinking that he may have esophageal cancer. He has had an influenza-like infection that lasted about 6 weeks in the past 3 months which exacerbated his asthma attacks. He used his puffers to relieve his symptoms and did not seek medical treatment. He is otherwise healthy. On examination, his blood pressure is 118/75 mm Hg, respirations are 17/min, pulse is 78/min, and temperature is 36.7°C (98.1°F). There is no evidence of enlarged lymph nodes or a sore throat. On palpation, the thyroid gland is enlarged and tender. He is a non-smoker with a BMI of 25 kg/m2. He has not used any medications recently. Which of the following is the most likely diagnosis?
A. Chronic lymphocytic thyroiditis
B. Lymphoma
C. Silent thyroiditis
D. Fibrous thyroiditis
E. Subacute granulomatous thyroiditis (Correct Answer)
Explanation: ***Subacute granulomatous thyroiditis***
- The presentation of an **enlarged and tender thyroid gland** following an **influenza-like infection** is highly characteristic of subacute granulomatous thyroiditis, also known as de Quervain's thyroiditis.
- The patient's dysphagia can be explained by the **inflammation and swelling of the thyroid gland** putting pressure on the esophagus, as the dysphagia is not progressive and has been present for a couple of months, also this is not a progressive dysphagia.
*Chronic lymphocytic thyroiditis*
- This condition, also known as **Hashimoto's thyroiditis**, typically presents with a **non-tender goiter** and often leads to hypothyroidism, which is not suggested by the current symptoms.
- While it is an autoimmune condition, it is not usually preceded by a viral infection leading to acute pain and tenderness.
*Lymphoma*
- Thyroid lymphoma usually presents as a **rapidly enlarging, firm, non-tender mass** in the neck, and may cause compressive symptoms.
- It is not typically preceded by an influenza-like illness and would likely involve more marked constitutional symptoms unrelated to thyroid dysfunction itself.
*Silent thyroiditis*
- Silent thyroiditis is characterized by a **painless goiter** and transient hyperthyroidism followed by hypothyroidism.
- The key differentiating factor here is the **absence of pain and tenderness** in silent thyroiditis, which are prominent features in this case.
*Fibrous thyroiditis*
- Also known as **Riedel's thyroiditis**, this is a rare condition characterized by a **hard, fixed, and painless thyroid gland** that can be mistaken for malignancy due to its invasive nature.
- It does not typically follow a viral infection and the thyroid is usually stony hard rather than tender.
Question 489: A 62-year-old female is brought to the hospital by her daughter. Six hours ago, she was at a wedding giving a speech when she suddenly experienced difficulty finding words and a right facial droop. She denies any extremity weakness, paresthesias, or sensory deficits. She has a history of hypertension and type 2 diabetes. She takes hydrochlorothiazide and insulin. Her last HbA1c was 10.3% four months ago. Vital signs are within normal limits. There is right lower facial droop on exam, but she is able to raise her eyebrows symmetrically. Speech is slow and slightly dysarthric. She has difficulty naming some objects. Her exam is otherwise unremarkable. Brain MRI shows a 3.2-cm infarct in the left frontal region. The patient is admitted to the neurology service for further management. On hospital day three her laboratory results show the following:
Serum
Na+ 131 mEq/L
Osmolality 265 mOsmol/kg H2O
Urine
Na+ 46 mEq/L
Osmolality 332 mOsmol/kg H2O
This patient is most likely to have which of the following additional findings?
A. Increased hydrostatic pressure
B. Decreased serum uric acid (Correct Answer)
C. Increased serum bicarbonate
D. Increased blood urea nitrogen
E. Increased urinary frequency
Explanation: ***Decreased serum uric acid***
- This patient's laboratory values are consistent with **syndrome of inappropriate antidiuretic hormone (SIADH)**, characterized by **hypotonic hyponatremia**, **low serum osmolality (<280 mOsmol/kg)**, and inappropriately **elevated urine osmolality (>100 mOsmol/kg)** with **urine sodium >40 mEq/L** in the setting of euvolemia.
- **SIADH** is commonly associated with **decreased serum uric acid (hypouricemia)** due to **increased fractional excretion of uric acid**. The volume expansion (relative to total body water) leads to increased glomerular filtration and decreased proximal tubular reabsorption of uric acid.
- CNS disorders, including stroke (as in this case), are a common cause of SIADH.
*Increased hydrostatic pressure*
- **Increased hydrostatic pressure** is associated with conditions causing edema such as **congestive heart failure**, cirrhosis, or venous obstruction.
- SIADH patients are typically **euvolemic** without peripheral edema, as the excess water is distributed throughout total body water rather than causing increased intravascular hydrostatic pressure.
*Increased serum bicarbonate*
- **Increased serum bicarbonate** (metabolic alkalosis) is not a feature of SIADH.
- Metabolic alkalosis typically results from acid loss (vomiting, NG suction), diuretic use, or mineralocorticoid excess, not from water retention.
*Increased blood urea nitrogen*
- In SIADH, patients are in a state of **euvolemia to mild volume expansion**, which typically leads to **decreased BUN** due to dilution and increased renal perfusion.
- **Increased BUN** would suggest hypovolemia, decreased renal perfusion, or intrinsic renal dysfunction—none of which are consistent with SIADH.
*Increased urinary frequency*
- SIADH is characterized by **inappropriate retention of water** with continued ADH activity despite hypo-osmolality.
- This leads to **concentrated urine** and typically **normal to decreased urine output**, not increased urinary frequency.
- The inappropriately elevated urine osmolality (332 mOsmol/kg) in this patient confirms water retention rather than increased urinary losses.
Question 490: A 67-year-old man presents to the emergency department for a headache. The patient states his symptoms started thirty minutes ago. He states he experienced a sudden and severe headache while painting his house, causing him to fall off the ladder and hit his head. He has also experienced two episodes of vomiting and difficulty walking since the fall. The patient has a past medical history of hypertension, obesity, and atrial fibrillation. His current medications include lisinopril, rivaroxaban, atorvastatin, and metformin. His temperature is 99.5°F (37.5°C), blood pressure is 150/105 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 98% on room air. On physical exam, the patient localizes his headache to the back of his head. Cardiac exam reveals a normal rate and rhythm. Pulmonary exam reveals minor bibasilar crackles. Neurological exam is notable for minor weakness of the muscles of facial expression. Examination of cranial nerve three reveals a notable nystagmus. Heel to shin exam is abnormal bilaterally. The patient's gait is notably ataxic. A non-contrast CT scan of the head is currently pending. Which of the following is the most likely diagnosis?
A. Pontine hemorrhage
B. Cerebellar hemorrhage (Correct Answer)
C. Subarachnoid hemorrhage
D. Thalamic hemorrhage
E. Subdural hematoma
Explanation: ***Cerebellar hemorrhage***
- The sudden onset of a **severe headache**, localized to the back of the head, combined with **ataxia**, nystagmus, and minor facial weakness, in a patient on **anticoagulation** (rivaroxaban) for atrial fibrillation, strongly suggests a cerebellar hemorrhage.
- **Vomiting** and **difficulty walking** are common symptoms due to the cerebellar involvement and increased intracranial pressure.
*Pontine hemorrhage*
- Pontine hemorrhages typically present with **quadriplegia**, profound **coma**, and **pinpoint pupils**, which are not observed in this patient.
- While it can cause sudden headache and vomiting, the specific neurological deficits (ataxia, nystagmus, mild facial weakness) are less characteristic of a pontine lesion.
*Subarachnoid hemorrhage*
- Characterized by a **"thunderclap" headache** (sudden and severe), often described as the "worst headache of my life," and can cause focal neurological deficits depending on the location of rupture.
- While the sudden onset and severity fit, the specific cerebellar signs (**nystagmus**, **ataxia**, posterior headache) point more directly to a cerebellar lesion, and the fall causing head trauma suggests a hemorrhage within the brain parenchyma.
*Thalamic hemorrhage*
- Thalamic hemorrhages commonly present with **contralateral hemisensory loss**, hemiparesis, and sometimes pupillary abnormalities.
- The patient's presentation with prominent **ataxia**, nystagmus, and posterior headache is less typical for a thalamic hemorrhage.
*Subdural hematoma*
- Subdural hematomas usually result from **trauma** and can have a more **insidious onset** (especially chronic subdural hematomas in elderly or anticoagulated patients).
- While the fall might suggest this, the acute onset of severe headache and the specific neurological signs like **ataxia** and nystagmus are more indicative of an intraparenchymal hemorrhage (like cerebellar) rather than a subdural collection compressing the brain surface.
