Respiratory MCQ's

Question 1

Answer 1

Correct answer: B. Lung abscess

Explanation:
This patient:

Is intubated during resuscitation

Aspires gastric contents

Develops fever and non-productive cough over days

Has a chest X-ray with a mass and air-fluid level

Sputum shows mixed flora

These are classic signs of a lung abscess, especially following aspiration.

Key Clues:
Aspiration pneumonia → lung abscess in 7–10 days

Air-fluid level on imaging is hallmark of lung abscess

Mixed flora indicates anaerobic and aerobic bacteria typical of oral/gastric flora

Why not the others?
A. Squamous cell carcinoma – may cavitate but not associated with aspiration or acute presentation

C. Chronic bronchitis – causes chronic cough; no cavitation or air-fluid level

D. Bronchiectasis – chronic, not post-aspiration; presents with recurrent infections and purulent sputum

E. Bronchopulmonary sequestration – congenital anomaly, not seen acutely post-aspiration

Conclusion:
Air-fluid level + aspiration history + fever = Lung abscess (B).

Question 2

Answer 2

Correct answer: B. Esophageal laceration

Explanation:
This 47-year-old man has:

A history of chronic alcohol use

Prolonged vomiting, now followed by massive hematemesis

Tachycardia, hypotension (suggesting hemorrhagic shock)

No occult blood in stool, meaning upper GI source

Most likely diagnosis:
Mallory-Weiss tear (a type of esophageal laceration) is strongly associated with:

Alcohol abuse

Repeated vomiting or retching

Sudden onset of hematemesis from a mucosal tear at the gastroesophageal junction

Why not the others?
A. Esophageal stricture – causes dysphagia, not hematemesis

C. Esophageal pulsion diverticulum (e.g., Zenker’s) – causes regurgitation and halitosis, not acute bleeding

D. Barrett esophagus – a metaplastic change due to reflux; not associated with acute bleeding

E. Esophageal squamous cell carcinoma – causes chronic bleeding and dysphagia, not massive hematemesis

Conclusion:
Alcohol + vomiting + hematemesis = Esophageal laceration (Mallory-Weiss tear) → Answer: B.

Question 3

Question:
A 58-year-old man has the sudden onset of severe pain in his left great toe. There is no history of trauma. On examination there is edema with erythema and pain on movement of the left 1st metatarsophalangeal joint, but there is no overlying skin ulceration. A joint aspirate is performed and on microscopic examination reveals numerous neutrophils and needle-shaped crystals. Over the next 3 weeks, he has two more similar episodes. On physical examination between these attacks, there is minimal loss of joint mobility. Which of the following laboratory test findings is most characteristic for his underlying disease process?

A. Hyperglycemia
B. Positive antinuclear antibody
C. Hyperuricemia
D. Hypercalcemia
E. High rheumatoid factor titer

Answer 3

Correct answer: C. Hyperuricemia

Explanation:
Needle-shaped crystals and neutrophils on joint aspirate are classic for gout.

Gout is caused by monosodium urate crystal deposition, typically in the 1st MTP joint.

The most characteristic lab finding is elevated serum uric acid (hyperuricemia).

Why not others?
A. Hyperglycemia – may coexist with gout, but not diagnostic.

B. Positive ANA – suggests lupus, not relevant here.

D. Hypercalcemia – associated with pseudogout (calcium pyrophosphate), which has rhomboid-shaped crystals.

E. High RF titer – seen in rheumatoid arthritis, not gout.

Conclusion: Sudden joint pain + needle-shaped crystals = Gout → Hyperuricemia (C).