MD Pulmonary Disease Management 4 — Questions and Answers
Question 1: A 28-year-old with cystic fibrosis has FEV1 of 40% predicted and is homozygous for F508del mutation. Which targeted therapy is most appropriate?
- Ivacaftor monotherapy
- Elexacaftor/tezacaftor/ivacaftor (ETI) (Correct answer)
- Lumacaftor/ivacaftor
- Ataluren
Correct answer: Elexacaftor/tezacaftor/ivacaftor (ETI)
Elexacaftor/tezacaftor/ivacaftor (Trikafta) is the most effective CFTR modulator for F508del homozygous patients, producing the greatest improvement in FEV1 and sweat chloride.
Question 2: A 67-year-old with a 50 pack-year smoking history undergoes low-dose CT screening. A 7 mm solid nodule is found. Per Lung-RADS, what is the recommended follow-up?
- Repeat LDCT in 12 months (annual screening)
- Repeat LDCT in 6 months (Correct answer)
- PET-CT scan immediately
- CT-guided biopsy
Correct answer: Repeat LDCT in 6 months
A 7 mm solid nodule in a high-risk screening patient is Lung-RADS 3 (probably benign), warranting a 6-month follow-up LDCT.
Question 3: A mechanically ventilated patient with ARDS has plateau pressure of 34 cmH2O despite tidal volume of 6 mL/kg IBW. Driving pressure is 18 cmH2O. What intervention has been shown to reduce mortality?
- Prone positioning for ≥16 hours/day (Correct answer)
- High-frequency oscillatory ventilation
- Extracorporeal CO2 removal
- Inhaled prostacyclin
Correct answer: Prone positioning for ≥16 hours/day
Prone positioning for ≥16 hours/day reduces mortality in moderate-to-severe ARDS (PaO2/FiO2 <150) as demonstrated in the PROSEVA trial.
Question 4: A 50-year-old presents with hemoptysis and a chest X-ray showing left lower lobe atelectasis with a central mass. Bronchoscopy reveals a carcinoid tumor. Which histologic finding would classify this as typical rather than atypical carcinoid?
- Greater than 10 mitoses per 10 HPF
- Fewer than 2 mitoses per 10 HPF with no necrosis (Correct answer)
- Necrosis present with 3-10 mitoses per 10 HPF
- Ki-67 index greater than 20%
Correct answer: Fewer than 2 mitoses per 10 HPF with no necrosis
Typical carcinoid is defined by fewer than 2 mitoses per 10 HPF and absence of necrosis; atypical carcinoid has 2-10 mitoses per 10 HPF or necrosis.
Question 5: A patient with moderate persistent asthma continues to have frequent exacerbations despite maximum-dose ICS/LABA. IgE is 450 IU/mL and blood eosinophils are 380 cells/μL. Which add-on biologic therapy is most appropriate?
- Benralizumab (anti-IL-5Rα)
- Dupilumab (anti-IL-4Rα)
- Omalizumab (anti-IgE) (Correct answer)
- Tezepelumab (anti-TSLP)
Correct answer: Omalizumab (anti-IgE)
Omalizumab is indicated for moderate-to-severe allergic asthma with elevated IgE and sensitivity to perennial allergens when uncontrolled on high-dose ICS/LABA.
Question 6: Which finding on methacholine challenge test indicates a positive result for bronchial hyperreactivity?
- ≥10% fall in FEV1 at 8 mg/mL concentration
- ≥20% fall in FEV1 at ≤16 mg/mL (PC20 ≤16 mg/mL) (Correct answer)
- ≥15% fall in FVC at any concentration
- ≥25% increase in airway resistance
Correct answer: ≥20% fall in FEV1 at ≤16 mg/mL (PC20 ≤16 mg/mL)
A positive methacholine challenge is defined as a ≥20% fall in FEV1 at a provocative concentration ≤16 mg/mL (PC20 ≤16 mg/mL).
Question 7: A 72-year-old with COPD and recurrent exacerbations (3 in past year) has FEV1 of 35% predicted and blood eosinophils of 320 cells/μL on dual LABA/LAMA therapy. Which is the most appropriate step-up?
- Add roflumilast
- Add inhaled corticosteroid (triple therapy) (Correct answer)
- Start azithromycin prophylaxis
- Initiate long-term oral corticosteroids
Correct answer: Add inhaled corticosteroid (triple therapy)
In COPD patients with frequent exacerbations and eosinophil count ≥300 cells/μL on dual bronchodilation, adding ICS (triple therapy) reduces exacerbation frequency.
MD Pulmonary Disease Management 4
A 28-year-old with cystic fibrosis has FEV1 of 40% predicted and is homozygous for F508del mutation.
Which targeted therapy is most appropriate?