Internal Medicine Exam Pulmonary Disease Essentials 4

Question 1

A 45-year-old HIV-positive patient (CD4 count 80 cells/μL) presents with dry cough, fever, and diffuse bilateral ground-glass opacities. LDH is elevated. What is the most likely diagnosis?

Accepted Answer

Pneumocystis jirovecii pneumonia (PCP)

Answer

PCP is the most common AIDS-defining opportunistic lung infection, typically presenting with subacute dry cough, hypoxia, elevated LDH, and bilateral ground-glass opacities when CD4 < 200.

Question 2

Which spirometry pattern is consistent with a diagnosis of restrictive lung disease?

Accepted Answer

FEV1/FVC ≥ 0.70 with reduced TLC

Answer

Restrictive lung disease is defined by reduced TLC (< 80% predicted) with a preserved or elevated FEV1/FVC ratio on spirometry.

Question 3

A 60-year-old man presents with obstructive sleep apnea confirmed on polysomnography with AHI of 32 events/hour and lowest SpO2 of 81%. He declines CPAP. What is the next best alternative therapy?

Accepted Answer

Mandibular advancement device

Answer

Mandibular advancement devices are the preferred alternative to CPAP in moderate-to-severe OSA when CPAP is declined, repositioning the jaw to enlarge the upper airway.

Question 4

A patient with ARDS is on mechanical ventilation. Current settings: TV 8 mL/kg IBW, PEEP 8 cmH2O, FiO2 0.70, plateau pressure 34 cmH2O. Which change should be made immediately?

Accepted Answer

Reduce tidal volume to 6 mL/kg IBW

Answer

The ARDSNet protocol mandates tidal volumes of 4-6 mL/kg IBW to limit ventilator-induced lung injury; plateau pressure > 30 cmH2O indicates overdistension requiring TV reduction.

Question 5

Which finding on Light's criteria indicates an exudative pleural effusion?

Accepted Answer

Pleural fluid LDH/serum LDH ratio > 0.6

Answer

Light's criteria identify exudate if any one of three criteria is met: pleural/serum protein > 0.5, pleural/serum LDH > 0.6, or pleural LDH > 2/3 upper limit of normal serum LDH.

Internal Medicine Exam Practice Test

Internal Medicine Exam Practice Test

Internal Medicine Exam Pulmonary Disease Essentials 4