NR 603– Full Questions, Answers and Rationales 2026 Update Graded A
1. A 58-year-old male with HTN and DM presents with acute onset of severe,
tearing chest pain radiating to the back. BP is 160/90 in right arm, 100/60 in left
arm. ECG normal. Most likely diagnosis?
Answer: Aortic dissection
Rationale: Tearing chest pain radiating to back + pulse differential = aortic
dissection until proven otherwise.
Distractors: MI (no ECG changes), PE (no hypoxia/tachycardia), GERD (no tearing
pain).
2. A 72-year-old female with sudden severe headache, nausea, and photophobia.
On exam, nuchal rigidity present. Next best step?
Answer: Non-contrast head CT
Rationale: Suspect subarachnoid hemorrhage; non-contrast CT first (high
sensitivity if done early). LP if CT negative.
Distractors: Lumbar puncture first (unsafe without CT), MRI (too slow), aspirin (no
therapeutic role acutely).
3. A 45-year-old with episodic palpitations, sweating, and headache lasting 10–15
minutes. BP 210/110 during episode. Most likely?
Answer: Pheochromocytoma
,Rationale: Paroxysmal HTN + palpitations + headache = catecholamine excess.
Distractors: Anxiety (not hypertensive this extreme), thyrotoxicosis (sustained
symptoms), panic disorder (no severe hypertension).
4. Which finding best differentiates heart failure with preserved ejection fraction
(HFpEF) from HFrEF?
Answer: Normal LVEF on echo
Rationale: HFpEF = EF ≥50%; HFrEF = EF <40%. Management differs.
Distractors: BNP elevated in both, JVD present in both, crackles in both.
5. A 30-year-old G3P2 at 32 weeks with new-onset HTN (150/95) and 2+
proteinuria. No headache or vision changes. Diagnosis?
Answer: Preeclampsia without severe features
Rationale: HTN + proteinuria after 20 weeks = preeclampsia. No severe features
yet.
Distractors: Gestational HTN (no proteinuria), eclampsia (seizures), chronic HTN
(onset before 20 weeks).
6. Best initial treatment for acute, uncomplicated cystitis in a non-pregnant
female without drug allergies?
Answer: Nitrofurantoin 100 mg BID x5 days
,Rationale: First-line per IDSA; low resistance, minimal systemic side effects.
Distractors: Ciprofloxacin (reserve for complicated), TMP-SMX (high resistance in
many areas), amoxicillin (poor efficacy).
7. A 55-year-old with COPD exacerbation, increased sputum purulence and
volume, and dyspnea. No fever. Best antibiotic choice if no risk factors for
Pseudomonas?
Answer: Doxycycline
Rationale: GOLD guidelines: for mild-moderate exacerbation without
pseudomonas risk, doxycycline or macrolide.
Distractors: Levofloxacin (ok but more side effects), azithromycin alone (can use
but doxy better if high resistance), amox-clav (second-line).
8. HPI: 4-year-old with barking cough, stridor, worse at night. Afebrile. Most
likely?
Answer: Croup (laryngotracheobronchitis)
Rationale: Barking cough + stridor + worse at night = viral croup.
Distractors: Epiglottitis (toxic, drooling), bacterial tracheitis (high fever, toxic),
asthma (wheezing, not stridor).
, 9. A 65-year-old diabetic with foot ulcer, surrounding erythema, no bone
exposure. Probe-to-bone test negative. Best imaging to rule out osteomyelitis?
Answer: MRI
Rationale: MRI is most sensitive/specific for osteomyelitis.
Distractors: X-ray (too insensitive early), bone scan (less specific), ultrasound (not
for bone).
10. A 28-year-old with knee swelling after twisting injury. Lachman test shows no
endpoint. Best next step?
Answer: MRI knee
Rationale: Suspect ACL tear; MRI confirms soft tissue injury.
Distractors: X-ray (rule out fracture only), CT (soft tissue poor), arthroscopy
(invasive second step).
11. A 50-year-old with gradually worsening dyspnea on exertion, nonproductive
cough, and bilateral fine late inspiratory crackles at bases. Most likely?
Answer: Idiopathic pulmonary fibrosis
Rationale: Velcro crackles + gradual dyspnea + older adult = IPF.
Distractors: CHF (S3, JVD), COPD (wheezing, prolonged expiration), pneumonia
(acute, fever).
1. A 58-year-old male with HTN and DM presents with acute onset of severe,
tearing chest pain radiating to the back. BP is 160/90 in right arm, 100/60 in left
arm. ECG normal. Most likely diagnosis?
Answer: Aortic dissection
Rationale: Tearing chest pain radiating to back + pulse differential = aortic
dissection until proven otherwise.
Distractors: MI (no ECG changes), PE (no hypoxia/tachycardia), GERD (no tearing
pain).
2. A 72-year-old female with sudden severe headache, nausea, and photophobia.
On exam, nuchal rigidity present. Next best step?
Answer: Non-contrast head CT
Rationale: Suspect subarachnoid hemorrhage; non-contrast CT first (high
sensitivity if done early). LP if CT negative.
Distractors: Lumbar puncture first (unsafe without CT), MRI (too slow), aspirin (no
therapeutic role acutely).
3. A 45-year-old with episodic palpitations, sweating, and headache lasting 10–15
minutes. BP 210/110 during episode. Most likely?
Answer: Pheochromocytoma
,Rationale: Paroxysmal HTN + palpitations + headache = catecholamine excess.
Distractors: Anxiety (not hypertensive this extreme), thyrotoxicosis (sustained
symptoms), panic disorder (no severe hypertension).
4. Which finding best differentiates heart failure with preserved ejection fraction
(HFpEF) from HFrEF?
Answer: Normal LVEF on echo
Rationale: HFpEF = EF ≥50%; HFrEF = EF <40%. Management differs.
Distractors: BNP elevated in both, JVD present in both, crackles in both.
5. A 30-year-old G3P2 at 32 weeks with new-onset HTN (150/95) and 2+
proteinuria. No headache or vision changes. Diagnosis?
Answer: Preeclampsia without severe features
Rationale: HTN + proteinuria after 20 weeks = preeclampsia. No severe features
yet.
Distractors: Gestational HTN (no proteinuria), eclampsia (seizures), chronic HTN
(onset before 20 weeks).
6. Best initial treatment for acute, uncomplicated cystitis in a non-pregnant
female without drug allergies?
Answer: Nitrofurantoin 100 mg BID x5 days
,Rationale: First-line per IDSA; low resistance, minimal systemic side effects.
Distractors: Ciprofloxacin (reserve for complicated), TMP-SMX (high resistance in
many areas), amoxicillin (poor efficacy).
7. A 55-year-old with COPD exacerbation, increased sputum purulence and
volume, and dyspnea. No fever. Best antibiotic choice if no risk factors for
Pseudomonas?
Answer: Doxycycline
Rationale: GOLD guidelines: for mild-moderate exacerbation without
pseudomonas risk, doxycycline or macrolide.
Distractors: Levofloxacin (ok but more side effects), azithromycin alone (can use
but doxy better if high resistance), amox-clav (second-line).
8. HPI: 4-year-old with barking cough, stridor, worse at night. Afebrile. Most
likely?
Answer: Croup (laryngotracheobronchitis)
Rationale: Barking cough + stridor + worse at night = viral croup.
Distractors: Epiglottitis (toxic, drooling), bacterial tracheitis (high fever, toxic),
asthma (wheezing, not stridor).
, 9. A 65-year-old diabetic with foot ulcer, surrounding erythema, no bone
exposure. Probe-to-bone test negative. Best imaging to rule out osteomyelitis?
Answer: MRI
Rationale: MRI is most sensitive/specific for osteomyelitis.
Distractors: X-ray (too insensitive early), bone scan (less specific), ultrasound (not
for bone).
10. A 28-year-old with knee swelling after twisting injury. Lachman test shows no
endpoint. Best next step?
Answer: MRI knee
Rationale: Suspect ACL tear; MRI confirms soft tissue injury.
Distractors: X-ray (rule out fracture only), CT (soft tissue poor), arthroscopy
(invasive second step).
11. A 50-year-old with gradually worsening dyspnea on exertion, nonproductive
cough, and bilateral fine late inspiratory crackles at bases. Most likely?
Answer: Idiopathic pulmonary fibrosis
Rationale: Velcro crackles + gradual dyspnea + older adult = IPF.
Distractors: CHF (S3, JVD), COPD (wheezing, prolonged expiration), pneumonia
(acute, fever).
