A plain CT scan of the patient's head is performed immediately and shows no evidence of hemorrhage. His temperature is 37.1°C (98.8°F), pulse is 101/min and blood pressure is 174/102 mm Hg. Which of the following is the most appropriate next step in management?
Q962
A 74-year-old right-handed woman was referred to the hospital due to concerns of a stroke. In the emergency department, the initial vital signs included blood pressure of 159/98 mm Hg, heart rate of 88/min, and respiratory rate of 20/min. She exhibited paucity of speech and apathy to her condition, although she complied with her physical examination. The initial neurologic evaluation included the following results:
Awake, alert, and oriented to person, place, and time
No visual field deficits
Right-sided gaze deviation with full range of motion with doll’s head maneuver
No facial asymmetry
Grossly intact hearing
No tongue deviation, equal palatal elevation, and good guttural sound production
Absent pronator or lower extremity drift
Decreased sensation to light touch on the right leg
Normal appreciation of light touch, pressure, and pain
Normal proprioception and kinesthesia
Manual muscle testing:
5+ right and left upper extremities
5+ right hip, thigh, leg, and foot
3+ left hip and thigh
2+ left leg and foot
A head computed tomography (CT) scan and a head magnetic resonance imaging (MRI) confirmed areas of ischemia. Which artery is the most likely site of occlusion?
Q963
A 34-year-old woman presents with fatigue, depressed mood, weight gain, and constipation. She gradually developed these symptoms over the past 6 months. She is G2P2 with the last pregnancy 9 months ago. She had a complicated delivery with significant blood loss requiring blood transfusions. She used to have a regular 28-day cycle but notes that recently it became irregular with duration lasting up to 40 days, more pain, and greater blood loss. She does not report any chronic conditions, and she is not on any medications. She is a current smoker with a 10-pack-year history. Her blood pressure is 130/80 mm Hg, heart rate is 54/min, respiratory rate is 11/min, and temperature is 35.8°C (96.4°F). Her skin is dry and pale with a fine scaling over the forearms and shins. There is a mild, non-pitting edema of the lower legs. Her lungs are clear to auscultation. Cardiac auscultation does not reveal any pathological sounds or murmurs although S1 and S2 are dulled at all points of auscultation. The abdomen is mildly distended and nontender on palpation. Neurological examination is significant for decreased deep tendon reflexes. Her blood tests show the following results:
Erythrocytes count 3.4 million/mm3
Hb 12.2 mg/dL
MCV 90 μm3
Reticulocyte count 0.3%
Leukocyte count 5,600/mm3
Serum vitamin B12 210 ng/mL
T4 total 1.01 μg/dL
T4 free 0.6 ng/dL
TSH 0.2 μIU/mL
Which of the following lab values should be used to monitor treatment in this patient?
Q964
A 38-year-old woman presents with worsening fatigue and difficulty talking for the last few hours. Past medical history is significant for type 2 diabetes mellitus, managed with metformin and insulin. Additional current medications are a pill to ''calm her nerves'' that she takes when she has to perform live on stage for work. On physical examination, the patient is lethargic, easily confused, and has difficulty responding to questions or commands. There is also significant diaphoresis of the face and trunk present. Which of the following is the most likely etiology of this patient’s current symptoms?
Q965
A 67-year-old woman comes to the clinic complaining of progressive fatigue over the past 4 months. She noticed that she is feeling increasingly short of breath after walking the same distance from the bus stop to her home. She denies chest pain, syncope, lower extremity edema, or a cough. She denies difficulty breathing while sitting comfortably, but she has increased dyspnea upon walking or other mildly strenuous activity. Her past medical history includes mild osteoporosis and occasional gastric reflux disease. She takes oral omeprazole as needed and a daily baby aspirin. The patient is a retired accountant and denies smoking history, but she does admit to 1 small glass of red wine daily for the past 5 years. Her diet consists of a Mediterranean diet that includes fruits, vegetables, and fish. She states that she has been very healthy previously, and managed her own health without a physician for the past 20 years. On physical examination, she has a blood pressure of 128/72 mm Hg, a pulse of 87/min, and an oxygen saturation of 94% on room air. HEENT examination demonstrates mild conjunctival pallor. Lung and abdominal examinations are within normal limits. Heart examination reveals a 2/6 systolic murmur at the right upper sternal border.
The following laboratory values are obtained:
Hematocrit 29%
Hemoglobin 9.8 g/dL
Mean red blood cell volume 78 fL
Platelets 240,000/mm3
White blood cells 6,000/mm3
What is the most likely reticulocyte range for this patient?
Q966
A 20-year-old female with type I diabetes mellitus presents to the emergency department with altered mental status. Her friend said that she has been out late either studying for upcoming tests or attending prayer group meetings. As far as the friend can recollect, the patient appeared to be in her usual state of health until only two days ago, when she was prescribed trimethoprim-sulfamethoxazole for a urinary tract infection. The patient complained that the medication was making her feel nauseous and bloated. The patient also relies on glargine and lispro for glycemic control. Her temperature is 100.5°F (38.1°C), blood pressure is 95/55 mmHg, pulse is 130/min, and respirations are 30/min. Her pupils are equal and reactive to light bilaterally. The remainder of the physical exam is unremarkable. Her basic metabolic panel is displayed below:
Serum:
Na+: 116 mEq/L
Cl-: 90 mEq/L
K+: 5.0 mEq/L
HCO3-: 2 mEq/L
BUN: 50 mg/dL
Glucose: 1,200 mg/dL
Creatinine: 1.5 mg/dL
Which of the following is true regarding this patient's presentation?
Q967
A 36-year-old man presents to his physician with an acute burning retrosternal sensation with radiation to his jaw. This sensation began 20 minutes ago when the patient was exercising at the gym. It does not change with position or with a cough. The patient’s vital signs include: blood pressure is 140/90 mm Hg, heart rate is 84/min, respiratory rate is 14/min, and temperature is 36.6℃ (97.9℉). Physical examination is only remarkable for paleness and perspiration. The patient is given sublingual nitroglycerin, the blood is drawn for an express troponin test, and an ECG is going to be performed. At the moment of performing ECG, the patient’s symptoms are gone. ECG shows increased R amplitude in I, II V3-V6, and ST depression measuring for 0.5 mm in the same leads. The express test for troponin is negative. Which of the following tests would be reasonable to perform next to confirm a diagnosis in this patient?
Q968
A 46-year-old woman complains of chronic cough for the past 3 weeks. She was recently diagnosed with hypertension and placed on an angiotensin receptor blocker therapy (ARBs). Chest X-ray shows large nodular densities bilaterally. Bronchial biopsy showed granulomatous inflammation of the pulmonary artery. Lab investigations showed a positive cANCA with a serum creatinine of 3.6 mg/dL. Urine analysis shows RBC casts and hematuria. Which is the most likely cause of this presentation?
Q969
A 67-year-old man presents to your office with a chief complaint of constipation and many other perturbing minor medical concerns. He reports tiring easily, which he attributes to old age and years of persistent pain in his back and ribs. A complete blood count shows low hemoglobin and elevated serum creatinine. A peripheral blood smear shows stacks of red blood cells among other findings, and serum electropheresis reveals an abnormal concentration of protein resulting in a spike. Which of the following additional findings would you expect to see in this patient?
Q970
A 55-year-old woman presents to a primary care clinic for a physical evaluation. She works as a software engineer, travels frequently, is married with 2 kids, and drinks alcohol occasionally. She does not exercise regularly. She currently does not take any medications except for occasional ibuprofen or acetaminophen. She is currently undergoing menopause. Her initial vital signs reveal that her blood pressure is 140/95 mmHg and heart rate is 75/min. She weighs 65 kg (143 lb) and is 160 cm (63 in) tall. Her physical exam is unremarkable. A repeat measurement of her blood pressure is the same as before. Among various laboratory tests for hypertension evaluation, the physician requests fasting glucose and hemoglobin A1c levels. Which of the following is the greatest risk factor for type 2 diabetes mellitus?
Cardiology US Medical PG Practice Questions and MCQs
Question 961: A plain CT scan of the patient's head is performed immediately and shows no evidence of hemorrhage. His temperature is 37.1°C (98.8°F), pulse is 101/min and blood pressure is 174/102 mm Hg. Which of the following is the most appropriate next step in management?
A. Oral aspirin therapy
B. Intravenous alteplase therapy (Correct Answer)
C. Surgical clipping
D. Decompressive surgery
E. Intravenous labetalol therapy
Explanation: ***Intravenous alteplase therapy***
- The immediate **non-contrast CT scan** is crucial to rule out **hemorrhagic stroke** before administering thrombolytic therapy.
- Given the likely diagnosis of **acute ischemic stroke** (implied by the urgency and the options), **alteplase** is indicated within the therapeutic window for eligible patients without contraindications.
*Oral aspirin therapy*
- **Aspirin** is indicated for acute ischemic stroke, but its administration is generally **delayed for 24 hours** after intravenous thrombolysis to reduce the risk of hemorrhagic transformation.
- If **alteplase** is contraindicated or not administered, aspirin should be given within 24-48 hours of stroke onset, but it is not the *most appropriate immediate next step* if thrombolysis is an option.
*Surgical clipping*
- **Surgical clipping** is primarily used to treat **unruptured or ruptured cerebral aneurysms** to prevent or stop bleeding, which is not the likely scenario based on the provided information (no mention of subarachnoid hemorrhage or aneurysm).
- This intervention is for **hemorrhagic stroke** due to aneurysm, not for acute ischemic stroke.
*Decompressive surgery*
- **Decompressive surgery** (e.g., craniectomy) is considered for large **malignant ischemic strokes** or severe **hemorrhagic strokes** with significant cerebral edema and impending herniation, to relieve intracranial pressure.
- It is a **later-stage intervention** for severe cases and not the immediate first-line treatment for acute stroke presentation.
*Intravenous labetalol therapy*
- **Blood pressure management** is important in acute stroke, but the primary goal in acute ischemic stroke, particularly if thrombolysis is considered, is to **maintain adequate cerebral perfusion** while controlling severe hypertension.
- While **labetalol** can be used to lower blood pressure, especially if above 185/110 mm Hg for thrombolysis or above 220/120 mm Hg otherwise, the *most appropriate next step* when eligible for thrombolysis is administering **alteplase** after confirming no hemorrhage and within the time window.
Question 962: A 74-year-old right-handed woman was referred to the hospital due to concerns of a stroke. In the emergency department, the initial vital signs included blood pressure of 159/98 mm Hg, heart rate of 88/min, and respiratory rate of 20/min. She exhibited paucity of speech and apathy to her condition, although she complied with her physical examination. The initial neurologic evaluation included the following results:
Awake, alert, and oriented to person, place, and time
No visual field deficits
Right-sided gaze deviation with full range of motion with doll’s head maneuver
No facial asymmetry
Grossly intact hearing
No tongue deviation, equal palatal elevation, and good guttural sound production
Absent pronator or lower extremity drift
Decreased sensation to light touch on the right leg
Normal appreciation of light touch, pressure, and pain
Normal proprioception and kinesthesia
Manual muscle testing:
5+ right and left upper extremities
5+ right hip, thigh, leg, and foot
3+ left hip and thigh
2+ left leg and foot
A head computed tomography (CT) scan and a head magnetic resonance imaging (MRI) confirmed areas of ischemia. Which artery is the most likely site of occlusion?
A. Superior division of the right middle cerebral artery
B. Right anterior cerebral artery (Correct Answer)
C. Right middle cerebral artery stem (M1)
D. Inferior division of the left middle cerebral artery
E. Inferior division of the right middle cerebral artery
Explanation: ***Right anterior cerebral artery***
- The patient's symptoms, including **left leg weakness** (3+ at hip/thigh, 2+ at leg/foot), **right gaze deviation**, and **apathy with paucity of speech**, are characteristic of a **right anterior cerebral artery (ACA) stroke**. The ACA supplies the motor and sensory cortices responsible for the contralateral leg and also the frontal lobe areas involved in executive function and motivation.
- **Urinary incontinence** is also a common feature of ACA strokes, though not explicitly mentioned here, the other symptoms strongly point to this localization.
*Superior division of the right middle cerebral artery*
- Occlusion of the superior division of the **right middle cerebral artery (MCA)** would typically cause **contralateral hemiparesis and hemisensory loss affecting the face and arm more than the leg**.
- As the patient is right-handed, a right MCA stroke would present with left-sided weakness, but the **leg involvement would be less pronounced** than what is seen here, and could also present with **gaze preference towards the right**, but speech would be spared.
*Right middle cerebral artery stem (M1)*
- A complete occlusion of the **right MCA stem (M1)** would result in a **dense contralateral hemiplegia** (face, arm, and leg equally affected), **contralateral hemianesthesia**, and a **homonymous hemianopia with gaze deviation to the right**.
- While gaze deviation to the right is present, the **predominant leg weakness** with sparing of the arm and face makes a complete M1 occlusion less likely.
*Inferior division of the left middle cerebral artery*
- Occlusion of the **inferior division of the left MCA** in a right-handed individual would lead to **Wernicke's aphasia** (fluent but nonsensical speech) and a right lower quadrantanopia, with less prominent motor deficits.
- The patient presents with **paucity of speech, not aphasia**, and left-sided motor deficits, not right.
*Inferior division of the right middle cerebral artery*
- An infarction in the **inferior division of the right MCA** would typically cause **left homonymous hemianopia or quadrantanopia** and potentially **left hemineglect**, with less significant motor or sensory deficits, unless the posterior limb of the internal capsule is also affected.
- The patient's primary symptoms of **leg weakness** and speech changes are not typical for an inferior division right MCA stroke.
Question 963: A 34-year-old woman presents with fatigue, depressed mood, weight gain, and constipation. She gradually developed these symptoms over the past 6 months. She is G2P2 with the last pregnancy 9 months ago. She had a complicated delivery with significant blood loss requiring blood transfusions. She used to have a regular 28-day cycle but notes that recently it became irregular with duration lasting up to 40 days, more pain, and greater blood loss. She does not report any chronic conditions, and she is not on any medications. She is a current smoker with a 10-pack-year history. Her blood pressure is 130/80 mm Hg, heart rate is 54/min, respiratory rate is 11/min, and temperature is 35.8°C (96.4°F). Her skin is dry and pale with a fine scaling over the forearms and shins. There is a mild, non-pitting edema of the lower legs. Her lungs are clear to auscultation. Cardiac auscultation does not reveal any pathological sounds or murmurs although S1 and S2 are dulled at all points of auscultation. The abdomen is mildly distended and nontender on palpation. Neurological examination is significant for decreased deep tendon reflexes. Her blood tests show the following results:
Erythrocytes count 3.4 million/mm3
Hb 12.2 mg/dL
MCV 90 μm3
Reticulocyte count 0.3%
Leukocyte count 5,600/mm3
Serum vitamin B12 210 ng/mL
T4 total 1.01 μg/dL
T4 free 0.6 ng/dL
TSH 0.2 μIU/mL
Which of the following lab values should be used to monitor treatment in this patient?
A. Free T4 (Correct Answer)
B. Vitamin B12
C. TSH
D. MCV
E. Total T3
Explanation: ***Free T4***
- This patient presents with **Sheehan syndrome**, which is a cause of **central hypothyroidism**. In central hypothyroidism, the **pituitary gland** fails to produce adequate TSH, leading to decreased T4 production by the thyroid gland.
- In cases of central hypothyroidism, **free T4** is the most reliable lab value to monitor treatment because TSH levels may not accurately reflect thyroid status due to pituitary dysfunction.
*Vitamin B12*
- Although the patient's vitamin B12 levels are on the lower end of the normal range, the clinical picture is not primarily consistent with **vitamin B12 deficiency**, and it is not the primary marker for monitoring this patient's underlying condition.
- While vitamin B12 deficiency can cause fatigue and neurological symptoms, the constellation of symptoms (bradycardia, hypothermia, dry skin, constipation, and menstrual irregularities) points more strongly to **hypothyroidism**.
*TSH*
- In **primary hypothyroidism**, TSH is elevated and is the primary parameter for monitoring treatment. However, in **central hypothyroidism** (as seen in Sheehan syndrome), TSH levels may be inappropriately low or normal even when thyroid hormone levels are deficient.
- Therefore, using **TSH** alone to monitor central hypothyroidism can be misleading as it does not accurately reflect the peripheral thyroid hormone status.
*MCV*
- The patient's **MCV (Mean Corpuscular Volume)** is normal, indicating that she does not have **macrocytic anemia**, which can be associated with hypothyroidism or vitamin B12 deficiency.
- While anemia can be a feature of hypothyroidism, MCV itself is not a direct marker for monitoring thyroid hormone treatment.
*Total T3*
- **Total T3** levels can be affected by **protein binding** and are generally less reliable than free T4 in assessing thyroid function, especially in the presence of confounding factors.
- **Free T4** is a direct measure of metabolically active thyroid hormone and is therefore a more accurate indicator for monitoring treatment in central hypothyroidism.
Question 964: A 38-year-old woman presents with worsening fatigue and difficulty talking for the last few hours. Past medical history is significant for type 2 diabetes mellitus, managed with metformin and insulin. Additional current medications are a pill to ''calm her nerves'' that she takes when she has to perform live on stage for work. On physical examination, the patient is lethargic, easily confused, and has difficulty responding to questions or commands. There is also significant diaphoresis of the face and trunk present. Which of the following is the most likely etiology of this patient’s current symptoms?
A. Diabetic ketoacidosis
B. Hyperosmolar nonketotic coma
C. Medication overdose
D. Hypoglycemia (Correct Answer)
E. Benzodiazepine intoxication
Explanation: ***Hypoglycemia***
- The patient's symptoms of **worsening fatigue, difficulty talking, lethargy, confusion, and diaphoresis** are classic signs of **hypoglycemia**.
- Her history of **type 2 diabetes mellitus** treated with **insulin** further supports this, as insulin can cause blood glucose levels to drop too low.
*Diabetic ketoacidosis*
- While diabetic ketoacidosis (DKA) can cause **lethargy and confusion**, it typically presents with **ketonuria, metabolic acidosis**, and often **polydipsia/polyuria**.
- **Diaphoresis** is not a common symptom of DKA; instead, patients are often dehydrated.
*Hyperosmolar nonketotic coma*
- Hyperosmolar nonketotic coma (HONK) is characterized by **severe hyperglycemia, dehydration, and altered mental status** without significant ketosis.
- While some symptoms like **lethargy and confusion** overlap, **diaphoresis** is not typical, and patients often present with profound dehydration.
*Medication overdose*
- Although the patient takes a "calming pill," the combination of symptoms and medical history points more strongly to a metabolic cause.
- A **medication overdose** would need more specific information about the drug and dosage to confirm, and the diaphoresis coupled with altered mental status fits hypoglycemia more precisely.
*Benzodiazepine intoxication*
- Benzodiazepine intoxication can cause **sedation, confusion, and slurred speech**, which can mimic some of the patient's symptoms.
- However, **significant diaphoresis** is not a typical hallmark of benzodiazepine intoxication, and the patient's diabetic history provides a more direct explanation.
Question 965: A 67-year-old woman comes to the clinic complaining of progressive fatigue over the past 4 months. She noticed that she is feeling increasingly short of breath after walking the same distance from the bus stop to her home. She denies chest pain, syncope, lower extremity edema, or a cough. She denies difficulty breathing while sitting comfortably, but she has increased dyspnea upon walking or other mildly strenuous activity. Her past medical history includes mild osteoporosis and occasional gastric reflux disease. She takes oral omeprazole as needed and a daily baby aspirin. The patient is a retired accountant and denies smoking history, but she does admit to 1 small glass of red wine daily for the past 5 years. Her diet consists of a Mediterranean diet that includes fruits, vegetables, and fish. She states that she has been very healthy previously, and managed her own health without a physician for the past 20 years. On physical examination, she has a blood pressure of 128/72 mm Hg, a pulse of 87/min, and an oxygen saturation of 94% on room air. HEENT examination demonstrates mild conjunctival pallor. Lung and abdominal examinations are within normal limits. Heart examination reveals a 2/6 systolic murmur at the right upper sternal border.
The following laboratory values are obtained:
Hematocrit 29%
Hemoglobin 9.8 g/dL
Mean red blood cell volume 78 fL
Platelets 240,000/mm3
White blood cells 6,000/mm3
What is the most likely reticulocyte range for this patient?
A. >7%
B. < 1% (Correct Answer)
C. >5%
D. > 1.5%
E. 0%
Explanation: ***< 1%***
- This patient presents with **microcytic anemia** (MCV 78 fL, Hgb 9.8 mg/dL) and symptoms of iron deficiency. A **low reticulocyte count** (< 1%) indicates the bone marrow is not adequately responding to the anemia, which is characteristic of iron deficiency due to chronic blood loss or malabsorption.
- The conjunctival pallor, systolic murmur, and chronic omeprazole use (which can impair iron absorption) further support the diagnosis of iron deficiency anemia.
*>7%*
- A reticulocyte count > 7% would suggest a **robust bone marrow response** to anemia, typically seen in conditions like **hemolytic anemia** or **acute blood loss** where the body is actively trying to replace lost red blood cells.
- This patient's clinical picture and microcytic anemia do not align with a highly regenerative bone marrow response.
*>5%*
- Similar to >7%, a reticulocyte count > 5% indicates a **significant regenerative anemia**, implying a rapid production of new red blood cells.
- This is inconsistent with the patient's **iron deficiency anemia**, where iron availability limits erythropoiesis and thus reticulocyte production.
*> 1.5%*
- A reticulocyte count > 1.5% (or > 2-3% as an absolute count) generally indicates a **mild to moderate regenerative anemia**.
- While it's slightly higher than what would be expected in uncompensated iron deficiency, it's still lower than what would be seen in highly regenerative anemias and higher than expected given the evidence of impaired erythropoiesis due to iron lack.
*0%*
- A reticulocyte count of 0% would indicate **complete cessation of red blood cell production** by the bone marrow, as seen in severe **aplastic anemia** or pure red cell aplasia.
- While the patient's anemia is chronic and likely due to iron deficiency, there is no evidence of complete bone marrow failure.
Question 966: A 20-year-old female with type I diabetes mellitus presents to the emergency department with altered mental status. Her friend said that she has been out late either studying for upcoming tests or attending prayer group meetings. As far as the friend can recollect, the patient appeared to be in her usual state of health until only two days ago, when she was prescribed trimethoprim-sulfamethoxazole for a urinary tract infection. The patient complained that the medication was making her feel nauseous and bloated. The patient also relies on glargine and lispro for glycemic control. Her temperature is 100.5°F (38.1°C), blood pressure is 95/55 mmHg, pulse is 130/min, and respirations are 30/min. Her pupils are equal and reactive to light bilaterally. The remainder of the physical exam is unremarkable. Her basic metabolic panel is displayed below:
Serum:
Na+: 116 mEq/L
Cl-: 90 mEq/L
K+: 5.0 mEq/L
HCO3-: 2 mEq/L
BUN: 50 mg/dL
Glucose: 1,200 mg/dL
Creatinine: 1.5 mg/dL
Which of the following is true regarding this patient's presentation?
A. Azotemia independently contributes to the patient's encephalopathy
B. Hyperglycemia to this magnitude supports hyperglycemic hyperosmolar nonketotic syndrome
C. Hypochloremia to this magnitude supports a pure anion-gap metabolic acidosis
D. Hyponatremia is independently associated with a poor prognosis
E. Hyperkalemia is independent of the patient's total body potassium stores (Correct Answer)
Explanation: ***Hyperkalemia is independent of the patient's total body potassium stores***
- In **diabetic ketoacidosis (DKA)**, intracellular potassium shifts extracellularly due to **acidemia** and **insulin deficiency**, leading to **normal or elevated serum potassium** despite depleted total body potassium stores.
- The patient's presentation with **DKA** (hyperglycemia, acidosis, altered mental status) coupled with a normal serum potassium level in the setting of significant fluid loss suggests a substantial deficit in total body potassium.
*Azotemia independently contributes to the patient's encephalopathy*
- While the patient has **elevated BUN and creatinine**, indicating **azotemia**, the primary cause of her altered mental status is likely **diabetic ketoacidosis (DKA)** with severe **hyperglycemia** and **acidosis**, leading to an **osmolar shift** and brain edema.
- Although severe azotemia can cause encephalopathy, in this context, the profound metabolic derangements of DKA are the more prominent contributors to her altered mental status.
*Hyperglycemia to this magnitude supports hyperglycemic hyperosmolar nonketotic syndrome*
- Although the glucose level is very high (1200 mg/dL), the presence of **severe metabolic acidosis** (HCO3- 2 mEq/L) is characteristic of **diabetic ketoacidosis (DKA)**, not hyperglycemic hyperosmolar nonketotic syndrome (HHNS).
- **HHNS** is typically characterized by extreme hyperglycemia, hyperosmolarity, and dehydration, but with **minimal or no ketosis or acidosis**.
*Hypochloremia to this magnitude supports a pure anion-gap metabolic acidosis*
- The patient has a **high anion-gap metabolic acidosis** (calculated anion gap = Na+ - (Cl- + HCO3-) = 116 - (90 + 2) = 24), which is characteristic of DKA.
- The **hypochloremia** is secondary to the profound dehydration and is often a response to the acidosis, but the primary acidosis is high anion-gap, not pure non-anion gap (hyperchloremic) acidosis.
*Hyponatremia is independently associated with a poor prognosis*
- The **hyponatremia** in this patient is largely **pseudohyponatremia** due to severe hyperglycemia, which draws water out of cells and dilutes serum sodium.
- While severe hyponatremia can indicate a poor prognosis in other contexts, in DKA, it often reflects the severity of hyperglycemia and dehydration, and corrects with resolution of hyperglycemia and fluid resuscitation; it is not an independent prognostic factor in this setting.
Question 967: A 36-year-old man presents to his physician with an acute burning retrosternal sensation with radiation to his jaw. This sensation began 20 minutes ago when the patient was exercising at the gym. It does not change with position or with a cough. The patient’s vital signs include: blood pressure is 140/90 mm Hg, heart rate is 84/min, respiratory rate is 14/min, and temperature is 36.6℃ (97.9℉). Physical examination is only remarkable for paleness and perspiration. The patient is given sublingual nitroglycerin, the blood is drawn for an express troponin test, and an ECG is going to be performed. At the moment of performing ECG, the patient’s symptoms are gone. ECG shows increased R amplitude in I, II V3-V6, and ST depression measuring for 0.5 mm in the same leads. The express test for troponin is negative. Which of the following tests would be reasonable to perform next to confirm a diagnosis in this patient?
A. Echocardiography
B. Chest radiography
C. CT angiography
D. Blood test for CPK-MB
E. Exercise stress testing (Correct Answer)
Explanation: ***Exercise stress testing***
- The patient's symptoms (chest pain radiating to the jaw, exacerbated by exercise, relieved by nitroglycerin) are highly suggestive of **angina**, despite the negative troponin and transient ECG changes.
- An **exercise stress test** is appropriate to evaluate for inducible ischemia, as it can reproduce symptoms and ECG changes under controlled conditions, helping to confirm a diagnosis of **coronary artery disease**.
*Echocardiography*
- While echocardiography can assess **cardiac function** and wall motion abnormalities, it primarily evaluates structural heart disease and myocardial function.
- It would not sufficiently confirm or rule out **exercise-induced ischemia** in a patient with resolved symptoms and normal initial workup for acute coronary syndrome.
*Chest radiography*
- **Chest radiography** provides images of the lungs, heart silhouette, and thoracic cage, primarily used to rule out pulmonary causes of chest pain or major structural abnormalities.
- It is not a diagnostic tool for **coronary artery disease** or exercise-induced angina.
*CT angiography*
- **CT angiography** is excellent for visualizing coronary arteries and detecting stenoses, but it involves radiation exposure and contrast.
- It is often reserved for patients with intermediate to high pre-test probability of CAD or when stress tests are inconclusive or contraindicated, not as a primary next step given the clinical picture and resolved symptoms.
*Blood test for CPK-MB*
- **Creatine phosphokinase-MB (CPK-MB)** is an older marker for myocardial damage, largely replaced by troponin due to its higher specificity and sensitivity.
- Since the **troponin test was negative**, further testing with a less sensitive marker like CPK-MB would not provide additional diagnostic value for acute myocardial injury.
Question 968: A 46-year-old woman complains of chronic cough for the past 3 weeks. She was recently diagnosed with hypertension and placed on an angiotensin receptor blocker therapy (ARBs). Chest X-ray shows large nodular densities bilaterally. Bronchial biopsy showed granulomatous inflammation of the pulmonary artery. Lab investigations showed a positive cANCA with a serum creatinine of 3.6 mg/dL. Urine analysis shows RBC casts and hematuria. Which is the most likely cause of this presentation?
A. Granulomatosis with polyangiitis (Correct Answer)
B. Hypertensive medication
C. Churg-Strauss syndrome
D. Polyarteritis nodosa
E. Microscopic polyangiitis
Explanation: ***Granulomatosis with polyangiitis***
- The combination of **chronic cough** with **bilateral nodular densities** on chest X-ray, **granulomatous inflammation** on lung biopsy, a **positive c-ANCA**, and rapidly progressive glomerulonephritis (elevated creatinine, RBC casts, hematuria) is highly characteristic of **Granulomatosis with polyangiitis (GPA)**.
- GPA is a small-vessel vasculitis that typically affects the **upper and lower respiratory tracts** and the **kidneys**.
*Hypertensive medication*
- While ACE inhibitors can cause a dry cough, **angiotensin receptor blockers (ARBs)**, which the patient is on, are typically not associated with cough.
- ARBs do not cause lung nodules, granulomatous inflammation, positive c-ANCA, or rapidly progressive glomerulonephritis.
*Churg-Strauss syndrome*
- **Churg-Strauss syndrome (Eosinophilic granulomatosis with polyangiitis)** characteristically presents with **asthma**, **eosinophilia**, and **allergic rhinitis**, which are not mentioned in this patient's presentation.
- Although it can cause lung involvement and vasculitis, the absence of prominent eosinophilia and allergic symptoms makes it less likely, and it is typically associated with p-ANCA, not c-ANCA.
*Microscopic polyangiitis*
- **Microscopic polyangiitis (MPA)** also causes necrotizing glomerulonephritis and pulmonary capillaritis, often with **p-ANCA positivity**.
- However, MPA typically lacks the **granulomatous inflammation** and **large nodular densities** seen in GPA.
*Polyarteritis nodosa*
- **Polyarteritis nodosa (PAN)** is a medium-vessel vasculitis that generally spares the **pulmonary circulation** and glomerulonephritis, distinguishing it from this case.
- PAN is typically **ANCA-negative** and does not involve granulomatous inflammation.
Question 969: A 67-year-old man presents to your office with a chief complaint of constipation and many other perturbing minor medical concerns. He reports tiring easily, which he attributes to old age and years of persistent pain in his back and ribs. A complete blood count shows low hemoglobin and elevated serum creatinine. A peripheral blood smear shows stacks of red blood cells among other findings, and serum electropheresis reveals an abnormal concentration of protein resulting in a spike. Which of the following additional findings would you expect to see in this patient?
A. Bence-Jones proteins in the urine (Correct Answer)
B. Smudge cells on peripheral smear
C. Early satiety and splenomegaly
D. No additional findings - normal aging explains symptoms
E. An elevated PSA and a nodular prostate
Explanation: ***Bence-Jones proteins in the urine***
- The constellation of symptoms (fatigue, bone pain, constipation, anemia, elevated creatinine, **rouleaux formation** on peripheral smear, and **monoclonal spike** on serum electrophoresis) is highly suggestive of **multiple myeloma**.
- **Bence-Jones proteins** (monoclonal light chains) are often excreted in the urine in multiple myeloma due to overproduction by malignant plasma cells.
*Smudge cells on peripheral smear*
- **Smudge cells** are characteristic of **chronic lymphocytic leukemia (CLL)**, a different hematologic malignancy that does not typically present with a monoclonal protein spike or extensive bone pain.
- While CLL can cause fatigue and anemia, it typically involves lymphadenopathy and does not present with the specific bone and kidney involvement seen here.
*Early satiety and splenomegaly*
- **Early satiety** and **splenomegaly** are common findings in **myeloproliferative neoplasms** (e.g., chronic myeloid leukemia, myelofibrosis) or lymphomas.
- These conditions do not present with a prominent **monoclonal protein spike** or the type of bone pain and renal dysfunction seen in this patient.
*No additional findings - normal aging explains symptoms*
- While some symptoms like fatigue and constipation can be associated with aging, the presence of **anemia**, **elevated creatinine**, **rouleaux formation**, and a **monoclonal protein spike** are **pathologic findings** that cannot be attributed to normal aging.
- These findings strongly indicate an underlying disease process requiring further investigation.
*An elevated PSA and a nodular prostate*
- These findings are indicative of **benign prostatic hyperplasia (BPH)** or **prostate cancer**, conditions of the prostate gland.
- While possible in an older male, they do not explain the systemic symptoms of bone pain, anemia, renal dysfunction, rouleaux formation, or the monoclonal protein spike, which point to a distinct hematologic malignancy.
Question 970: A 55-year-old woman presents to a primary care clinic for a physical evaluation. She works as a software engineer, travels frequently, is married with 2 kids, and drinks alcohol occasionally. She does not exercise regularly. She currently does not take any medications except for occasional ibuprofen or acetaminophen. She is currently undergoing menopause. Her initial vital signs reveal that her blood pressure is 140/95 mmHg and heart rate is 75/min. She weighs 65 kg (143 lb) and is 160 cm (63 in) tall. Her physical exam is unremarkable. A repeat measurement of her blood pressure is the same as before. Among various laboratory tests for hypertension evaluation, the physician requests fasting glucose and hemoglobin A1c levels. Which of the following is the greatest risk factor for type 2 diabetes mellitus?
A. Menopause
B. Occupation
C. Age
D. Body mass index (Correct Answer)
E. Hypertension
Explanation: ***Body mass index***
- The patient's **BMI** is 25.4 kg/m², which falls into the **overweight** category (BMI 25-29.9 kg/m²). **Obesity** (BMI ≥ 30 kg/m²) and overweight status are significant and modifiable risk factors for **insulin resistance** and type 2 diabetes mellitus.
- Excess body fat, particularly **visceral fat**, leads to increased free fatty acid release and inflammation, impairing insulin signaling in target tissues.
*Menopause*
- While menopause can lead to changes in **body fat distribution** and increase the risk of metabolic syndrome components, it is not as strong a direct risk factor for type 2 diabetes as BMI.
- The hormonal shifts during menopause may contribute to **insulin resistance** but do not independently confer as high a risk as overweight or obesity.
*Occupation*
- The patient's occupation as a **software engineer** and frequent travel may contribute to a sedentary lifestyle, which is an indirect risk factor for obesity and diabetes. However, occupation itself is not a direct or primary biological risk factor.
- A sedentary lifestyle decreases **metabolic demand** and can lead to weight gain if not balanced with regular physical activity.
*Age*
- **Advancing age** is a known risk factor for type 2 diabetes due to a gradual decline in pancreatic beta-cell function and increased insulin resistance over time.
- While the patient's age (55) is a risk factor, her elevated **BMI** represents a more immediate and modifiable risk for developing the disease.
*Hypertension*
- **Hypertension** is often a comorbidity of type 2 diabetes and part of the **metabolic syndrome**, but it is generally considered a consequence or co-existing condition rather than the primary risk factor for the development of diabetes itself.
- Both hypertension and type 2 diabetes share common pathophysiological mechanisms such as **insulin resistance** and inflammation.