1
NR 507 Midterm Exam 2026 | All Questions and
Correct Answers | Verified Answers | Graded A+ |
Updated Version
Exam Instructions
• Format: Multiple Choice
• Focus: Immunity, Inflammation, Alterations in Hematology, Cardiovascular, Pulmonary, Renal,
and Neurology.
• Level: High-difficulty (application-based).
Section I: Immunity & Inflammation
Question 1
A 32-year-old female presents with a butterfly rash on her face, polyarthralgia, and fatigue. Laboratory
findings reveal positive antinuclear antibodies (ANA) and anti-dsDNA antibodies. Which of the following
pathophysiological mechanisms best explains the renal failure this patient is at highest risk for
developing?
A) Deposition of immune complexes in the glomerular basement membrane leading to Type III
hypersensitivity.
B) Autoantibodies targeting the podocytes leading to minimal change disease.
C) T-cell mediated cytotoxic attack on the proximal tubule cells.
D) Activation of mast cells leading to vasodilation and decreased perfusion.
Correct Answer-: A
Rationale: Systemic Lupus Erythematosus (SLE) is a classic Type II (cytotoxic) and Type III (immune
complex) hypersensitivity disorder. The anti-dsDNA antibodies form immune complexes that deposit in
the glomeruli, causing a proliferative glomerulonephritis (Class IV), which is the leading cause of
morbidity and mortality.
Question 2
Rotated Question: A patient with a history of severe allergic reactions to bee stings is brought to the ER
after being stung. They are hypotensive, wheezing, and have diffuse urticaria. Which of the following
mediators is primarily responsible for the bronchospasm observed in this acute reaction?
A) Histamine binding to H2 receptors on smooth muscle.
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B) Leukotrienes C4, D4, and E4.
C) Interleukin-2 (IL-2) activating T-regulatory cells.
D) Complement C5a anaphylatoxin.
Correct Answer-: B
Rationale: While histamine causes early-phase vasodilation and bronchospasm, leukotrienes (especially
LTD4) are the potent mediators responsible for the prolonged, severe bronchospasm and mucus
hypersecretion seen in anaphylaxis. H2 receptors are primarily gastric, not bronchial.
Section II: Hematology
Question 3
A 24-year-old African American male presents with severe pain in his hands and feet, fatigue, and
jaundice. A peripheral blood smear shows sickle cells. If this patient develops acute chest syndrome,
what is the underlying pathological mechanism?
A) Iron overload leading to cardiomyopathy and pulmonary edema.
B) Vitamin B12 deficiency causing ineffective erythropoiesis.
C) Vaso-occlusion of pulmonary microvasculature leading to infarction and infection.
D) Autoimmune destruction of platelets causing pulmonary hemorrhage.
Correct Answer-: C
Rationale: Acute chest syndrome in Sickle Cell Disease is a leading cause of death. It results from the
vaso-occlusion of sickled RBCs in the pulmonary vasculature, leading to lung infarction, inflammation,
and often superimposed infection (e.g., Mycoplasma, Chlamydia).
Question 4
Rotated Question: A 65-year-old patient with chronic kidney disease (Stage 4) presents with fatigue and
pallor. Lab results: Hgb 8.5 g/dL, MCV 82 fL (normal), reticulocyte count low. Which of the following best
explains the pathophysiology of this anemia?
A) Autoimmune destruction of RBCs in the spleen.
B) Decreased production of erythropoietin by the peritubular interstitial cells of the kidney.
C) Iron deficiency due to chronic blood loss from uremic gastritis.
D) Hemolysis due to fragmentation from calcified vessels.
Correct Answer-: B
Rationale: The kidney produces erythropoietin (EPO) in response to hypoxia. In chronic kidney disease,
the loss of peritubular interstitial cells (fibroblasts) results in insufficient EPO production, leading to a
normocytic, normochromic anemia.
Section III: Cardiovascular
Question 5
A patient is diagnosed with left-sided heart failure. Which of the following clinical findings is a direct
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result of the backward failure pathophysiology?
A) Jugular venous distention (JVD).
B) Dyspnea and pulmonary crackles.
C) Hepatomegaly.
D) Peripheral edema.
Correct Answer-: B
Rationale: "Backward failure" of the left ventricle causes blood to back up into the left atrium and
subsequently into the pulmonary circulation. This increases hydrostatic pressure in the pulmonary
capillaries, leading to pulmonary congestion (dyspnea, crackles). JVD, hepatomegaly, and peripheral
edema are signs of right-sided heart failure.
Question 6
Rotated Question: A 55-year-old male with a history of hypertension presents with a tearing chest pain
radiating to the back. A CT angiogram reveals an intimal flap in the ascending aorta. What is the most
critical immediate pathophysiological concern?
A) Myocardial infarction due to coronary artery compression.
B) Hemopericardium leading to cardiac tamponade.
C) Stroke due to carotid artery dissection.
D) Acute aortic regurgitation.
Correct Answer-: B
Rationale: While A, C, and D can occur with aortic dissection, the most critical immediate life-
threatening concern for a Type A (ascending) dissection is rupture into the pericardial space,
causing cardiac tamponade. This is the leading cause of immediate death if not surgically repaired.
Section IV: Pulmonary
Question 7
A patient with a long history of smoking presents with a barrel-shaped chest, hyperresonance on
percussion, and prolonged expiration. Pulmonary function tests show a decreased FEV1/FVC ratio and
an increased total lung capacity (TLC). What is the primary mechanism causing the increased TLC in this
condition?
A) Loss of elastic recoil leading to air trapping.
B) Fibrosis of the alveolar walls restricting expansion.
C) Muscular hypertrophy of the bronchioles.
D) Excessive mucus production plugging the airways.
Correct Answer-: A
Rationale: This describes emphysema (COPD). The destruction of alveolar walls and elastin fibers (due to
protease-antiprotease imbalance) results in loss of elastic recoil. This makes it difficult to exhale air,
leading to air trapping (auto-PEEP) and hyperinflation, which manifests as an increased TLC.
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Question 8
Rotated Question: A 30-year-old female presents with acute shortness of breath and pleuritic chest pain
5 days after a long international flight. She is tachycardic and hypoxic. A CTA shows a filling defect in the
left pulmonary artery. Which of the following pathophysiological changes is most directly responsible for
her hypoxemia?
A) Ventilation-perfusion (V/Q) mismatch.
B) Shunting (anatomical shunt).
C) Diffusion limitation.
D) Hypoventilation.
Correct Answer-: A
Rationale: Pulmonary embolism causes a V/Q mismatch. There is ventilation (air moving to alveoli) but
no perfusion (blood cannot flow past the clot to pick up oxygen). This creates "dead space." While a
massive PE can cause a shunt if the foramen ovale opens (right-to-left), the primary mechanism for
hypoxemia in most PEs is V/Q mismatch.
Section V: Renal & Fluid/Electrolyte
Question 9
A 70-year-old male with heart failure is started on a diuretic. He presents with confusion, muscle
weakness, and ECG changes showing a flattened T wave and a prominent U wave. What is the
underlying cellular pathophysiology causing these ECG changes?
A) Increased sodium permeability leading to rapid depolarization.
B) Decreased potassium conductance leading to prolonged repolarization.
C) Calcium influx blockade causing a prolonged QT interval.
D) Magnesium wasting causing torsades de pointes.
Correct Answer-: B
Rationale: The symptoms describe hypokalemia (low potassium). ECG changes (flattened T, U wave)
occur because low extracellular K+ increases the negativity of the resting membrane potential and
decreases potassium conductance (delayed rectifier), prolonging repolarization (QT interval).
Question 10
Rotated Question: A patient with cirrhosis and ascites develops bacterial peritonitis. He suddenly
becomes oliguric. Labs: BUN 80 mg/dL, Cr 2.5 mg/dL (baseline 1.0). Urinalysis shows no casts, and urine
sodium is <10 mEq/L. What is the primary mechanism of this renal failure?
A) Acute tubular necrosis (ATN) due to nephrotoxic drugs.
B) Post-renal obstruction due to uric acid crystals.
C) Prerenal azotemia due to splanchnic vasodilation and effective arterial blood volume depletion.
D) Glomerulonephritis due to immune complex deposition.
Correct Answer-: C
Rationale: This describes Hepatorenal Syndrome. The pathophysiology is extreme splanchnic arterial
vasodilation (due to portal hypertension), which reduces effective arterial blood volume, activating the
NR 507 Midterm Exam 2026 | All Questions and
Correct Answers | Verified Answers | Graded A+ |
Updated Version
Exam Instructions
• Format: Multiple Choice
• Focus: Immunity, Inflammation, Alterations in Hematology, Cardiovascular, Pulmonary, Renal,
and Neurology.
• Level: High-difficulty (application-based).
Section I: Immunity & Inflammation
Question 1
A 32-year-old female presents with a butterfly rash on her face, polyarthralgia, and fatigue. Laboratory
findings reveal positive antinuclear antibodies (ANA) and anti-dsDNA antibodies. Which of the following
pathophysiological mechanisms best explains the renal failure this patient is at highest risk for
developing?
A) Deposition of immune complexes in the glomerular basement membrane leading to Type III
hypersensitivity.
B) Autoantibodies targeting the podocytes leading to minimal change disease.
C) T-cell mediated cytotoxic attack on the proximal tubule cells.
D) Activation of mast cells leading to vasodilation and decreased perfusion.
Correct Answer-: A
Rationale: Systemic Lupus Erythematosus (SLE) is a classic Type II (cytotoxic) and Type III (immune
complex) hypersensitivity disorder. The anti-dsDNA antibodies form immune complexes that deposit in
the glomeruli, causing a proliferative glomerulonephritis (Class IV), which is the leading cause of
morbidity and mortality.
Question 2
Rotated Question: A patient with a history of severe allergic reactions to bee stings is brought to the ER
after being stung. They are hypotensive, wheezing, and have diffuse urticaria. Which of the following
mediators is primarily responsible for the bronchospasm observed in this acute reaction?
A) Histamine binding to H2 receptors on smooth muscle.
,2
B) Leukotrienes C4, D4, and E4.
C) Interleukin-2 (IL-2) activating T-regulatory cells.
D) Complement C5a anaphylatoxin.
Correct Answer-: B
Rationale: While histamine causes early-phase vasodilation and bronchospasm, leukotrienes (especially
LTD4) are the potent mediators responsible for the prolonged, severe bronchospasm and mucus
hypersecretion seen in anaphylaxis. H2 receptors are primarily gastric, not bronchial.
Section II: Hematology
Question 3
A 24-year-old African American male presents with severe pain in his hands and feet, fatigue, and
jaundice. A peripheral blood smear shows sickle cells. If this patient develops acute chest syndrome,
what is the underlying pathological mechanism?
A) Iron overload leading to cardiomyopathy and pulmonary edema.
B) Vitamin B12 deficiency causing ineffective erythropoiesis.
C) Vaso-occlusion of pulmonary microvasculature leading to infarction and infection.
D) Autoimmune destruction of platelets causing pulmonary hemorrhage.
Correct Answer-: C
Rationale: Acute chest syndrome in Sickle Cell Disease is a leading cause of death. It results from the
vaso-occlusion of sickled RBCs in the pulmonary vasculature, leading to lung infarction, inflammation,
and often superimposed infection (e.g., Mycoplasma, Chlamydia).
Question 4
Rotated Question: A 65-year-old patient with chronic kidney disease (Stage 4) presents with fatigue and
pallor. Lab results: Hgb 8.5 g/dL, MCV 82 fL (normal), reticulocyte count low. Which of the following best
explains the pathophysiology of this anemia?
A) Autoimmune destruction of RBCs in the spleen.
B) Decreased production of erythropoietin by the peritubular interstitial cells of the kidney.
C) Iron deficiency due to chronic blood loss from uremic gastritis.
D) Hemolysis due to fragmentation from calcified vessels.
Correct Answer-: B
Rationale: The kidney produces erythropoietin (EPO) in response to hypoxia. In chronic kidney disease,
the loss of peritubular interstitial cells (fibroblasts) results in insufficient EPO production, leading to a
normocytic, normochromic anemia.
Section III: Cardiovascular
Question 5
A patient is diagnosed with left-sided heart failure. Which of the following clinical findings is a direct
,3
result of the backward failure pathophysiology?
A) Jugular venous distention (JVD).
B) Dyspnea and pulmonary crackles.
C) Hepatomegaly.
D) Peripheral edema.
Correct Answer-: B
Rationale: "Backward failure" of the left ventricle causes blood to back up into the left atrium and
subsequently into the pulmonary circulation. This increases hydrostatic pressure in the pulmonary
capillaries, leading to pulmonary congestion (dyspnea, crackles). JVD, hepatomegaly, and peripheral
edema are signs of right-sided heart failure.
Question 6
Rotated Question: A 55-year-old male with a history of hypertension presents with a tearing chest pain
radiating to the back. A CT angiogram reveals an intimal flap in the ascending aorta. What is the most
critical immediate pathophysiological concern?
A) Myocardial infarction due to coronary artery compression.
B) Hemopericardium leading to cardiac tamponade.
C) Stroke due to carotid artery dissection.
D) Acute aortic regurgitation.
Correct Answer-: B
Rationale: While A, C, and D can occur with aortic dissection, the most critical immediate life-
threatening concern for a Type A (ascending) dissection is rupture into the pericardial space,
causing cardiac tamponade. This is the leading cause of immediate death if not surgically repaired.
Section IV: Pulmonary
Question 7
A patient with a long history of smoking presents with a barrel-shaped chest, hyperresonance on
percussion, and prolonged expiration. Pulmonary function tests show a decreased FEV1/FVC ratio and
an increased total lung capacity (TLC). What is the primary mechanism causing the increased TLC in this
condition?
A) Loss of elastic recoil leading to air trapping.
B) Fibrosis of the alveolar walls restricting expansion.
C) Muscular hypertrophy of the bronchioles.
D) Excessive mucus production plugging the airways.
Correct Answer-: A
Rationale: This describes emphysema (COPD). The destruction of alveolar walls and elastin fibers (due to
protease-antiprotease imbalance) results in loss of elastic recoil. This makes it difficult to exhale air,
leading to air trapping (auto-PEEP) and hyperinflation, which manifests as an increased TLC.
, 4
Question 8
Rotated Question: A 30-year-old female presents with acute shortness of breath and pleuritic chest pain
5 days after a long international flight. She is tachycardic and hypoxic. A CTA shows a filling defect in the
left pulmonary artery. Which of the following pathophysiological changes is most directly responsible for
her hypoxemia?
A) Ventilation-perfusion (V/Q) mismatch.
B) Shunting (anatomical shunt).
C) Diffusion limitation.
D) Hypoventilation.
Correct Answer-: A
Rationale: Pulmonary embolism causes a V/Q mismatch. There is ventilation (air moving to alveoli) but
no perfusion (blood cannot flow past the clot to pick up oxygen). This creates "dead space." While a
massive PE can cause a shunt if the foramen ovale opens (right-to-left), the primary mechanism for
hypoxemia in most PEs is V/Q mismatch.
Section V: Renal & Fluid/Electrolyte
Question 9
A 70-year-old male with heart failure is started on a diuretic. He presents with confusion, muscle
weakness, and ECG changes showing a flattened T wave and a prominent U wave. What is the
underlying cellular pathophysiology causing these ECG changes?
A) Increased sodium permeability leading to rapid depolarization.
B) Decreased potassium conductance leading to prolonged repolarization.
C) Calcium influx blockade causing a prolonged QT interval.
D) Magnesium wasting causing torsades de pointes.
Correct Answer-: B
Rationale: The symptoms describe hypokalemia (low potassium). ECG changes (flattened T, U wave)
occur because low extracellular K+ increases the negativity of the resting membrane potential and
decreases potassium conductance (delayed rectifier), prolonging repolarization (QT interval).
Question 10
Rotated Question: A patient with cirrhosis and ascites develops bacterial peritonitis. He suddenly
becomes oliguric. Labs: BUN 80 mg/dL, Cr 2.5 mg/dL (baseline 1.0). Urinalysis shows no casts, and urine
sodium is <10 mEq/L. What is the primary mechanism of this renal failure?
A) Acute tubular necrosis (ATN) due to nephrotoxic drugs.
B) Post-renal obstruction due to uric acid crystals.
C) Prerenal azotemia due to splanchnic vasodilation and effective arterial blood volume depletion.
D) Glomerulonephritis due to immune complex deposition.
Correct Answer-: C
Rationale: This describes Hepatorenal Syndrome. The pathophysiology is extreme splanchnic arterial
vasodilation (due to portal hypertension), which reduces effective arterial blood volume, activating the
