Interstitial Lung Disease

Question 1

Idiopathic interstitial lung disease clinically characterized by sudden onset of dyspnea and rapid development of respiratory failure

Answer 1

Acute interstitial pneumonia [aka Hamman-Rich syndrome]

Question 2

Acute interstitial pneumonia (AIP) is histologically characterized by _______ with subsequent ______

Answer 2

Diffuse alveolar damage; fibrosis

Question 3

Compare/contrast acute interstitial pneumonia and idiopathic pulmonary fibrosis in terms of age group, etiology, pattern, onset and presentation, and diagnosis

Answer 3

AIP occurs in pts from all age groups (mostly adults), has no specific etiology, pattern is diffuse, symmetric, and bilateral, abrupt onset with flu-like sxs, and dx is based on biopsy

IPF occurs almost exclusively in adults, if often related back to causative exposure, pattern is asymmetric and favors upper or lower lobes, onset is gradual and pt is afebrile, and dx is based on hx/clinical findings, imaging, and PFTs (bx is optional)

Question 4

Anti-fibrotic medications are only used in what specific interstitial lung disease?

Answer 4

Idiopathic pulmonary fibrosis

Question 5

Prototypic presentation of interstitial lung disease

Answer 5

Dyspnea, cough, crackles described as sounding like “velcro” primarily at lung bases, digital clubbing, and exercise-induced hypoxemia

Question 6

Describe evaluation of a pt with presumed interstitial lung dz (what tests are done?)

Answer 6

PFTs

Chest CT

ANA and rheumatoid factor

Evaluation must also include history — occupation, hobby, environmental, travel, drugs (both Rx and Non-Rx)

Question 7

What do PFTs show with interstitial lung dz?

Answer 7

Reduced FRC and TLC

Normal FEV1/FVC

Low DLCO

Question 8

3 Common drugs associated with interstitial lung disease

Answer 8

Amiodarone — cardiac antiarrhythmic; dose-related

Bleomycin — chemotherapy agent

Nitrofurantoin — antibiotic commonly used for UTI

[others include methotrexate and busulfan]

Question 9

Asbestosis is a type of ILD associated with what occupations? What is the characteristic feature?

Answer 9

Construction workers
Plumbers
Shipyard workers, including “chippers”

Shows PLEURAL PLAQUES

Question 10

Silicosis is a type of ILD associated with what occupations?

Answer 10

Sand blasters
Silica miners
Spelunkers (“spelunker’s lung”)

Question 11

ILD found in coal miners

Answer 11

Coal worker’s pneumoconiosis

Question 12

Berylliosis is a type of ILD found in what occupations?

Answer 12

Beryllium miners

Workers in aerospace industry

Question 13

When it is known, the underlying cause of ILD is the target of treatment. If ILD is not due to IPF, ______ are typically used

Answer 13

Corticosteroids [very effective when induced by radiation]

Question 14

Antifibrotic tx options for IPF

Answer 14

Pirfenidone — antifibrotic and anti-inflammatory [specific action unknown]

Nintendanib — tyrosine kinase inhibitor; targets inflammatory and profibrotic factors

Question 15

Name the disease:

Most cases are either asymptomatic or have mild dz; often found incidentally on chest radiograph. CXR is fairly symmetrical (not so with chest CT). In a small number of people this can be a devastating dz and lead to severe disability and death. Prednisone is the tx of choice

Answer 15

Sarcoidosis

Question 16

ILD vs. COPD

Answer 16

ILD has more rapid decline and the cough is usually nonproductive

COPD has slower decline with more frequent exacerbations; weather and NSAIDs worsen symptoms; cough is productive

Question 17

Acute vs. chronic form of hypersensitivity pneumonitis

Answer 17

Acute: abrupt onset of dyspnea, cough, fever, +/- myalgias

Chronic: pulmonary fibrosis

Question 18

Autoimmune condition that may contribute to ILD; extra-pulmonary restriction sometimes referred to as “shrinking lung syndrome”; may be characterized by pulmonary HTN and pleural dz

Answer 18

SLE

Question 19

Name the disease:

Interstitial pulmonary fibrosis
Bronchiectasis
Pulmonary nodules
Pulmonary vasculitis
Pleural disease (very low pleural glucose is characteristic)

Answer 19

Rheumatoid arthritis

Question 20

An 83 y/o female nonsmoker presents with 3 years of progressive dyspnea and recent development of nonproductive cough. There is no variation with weather changes or exposure to NSAIDs. She denies orthopnea, edema, or PND. No recent travel. She has worked as a secretary for 38 years. Her hobbies include crocheting, knitting, and reading, and she was a spelunker until 30 years ago. Her exam is normal except for O2 sat 84%, slight accessory respiratory muscle use, 1-2 cm hemi-diaphragmatic percussion, and diffuse bisilar crackles. PFTs reveal FVC 50%, FEV1 45%, FEV1/FVC 90%, FRC 50%, RV 48%, TLC 58%, and DLCO 34%. The most likely diagnosis is:

A. Idiopathic pulmonary fibrosis
B. Emphysema
C. Silicosis
D. Asbestosis
E. Radiation pneumonitis

Answer 20

C. Silicosis

[“spelunker’s lung”]

Question 21

A 58 y/o man is evaluated for insidious onset of slowly progressive dyspnea over the last 3 years. At this point, he must stop to rest when walking 1 block. Previously, he walked 1-2 miles daily without difficulty. He denies cough, chest pain, or orthopnea. He has no other medical problems. PE reveals BMI of 35, O2 sat 93% RA, dry crackles on auscultation, parasternal heave and persistent splitting of S2. PFTs reveal FEV1 60%, FEV1/FVC 80%, TLC 70%, DLCO 45%. CXR shows diffuse reticular infiltrates in upper lung zones. Which of the folowing is the most likely diagnosis?

A. Diffuse parenchymal lung disease
B. Heart failure
C. Obesity hypoventilation syndrome
D. Obstructive airway disease
E. Respiratory muscle weakness

Answer 21

A. Diffuse parenchymal lung disease

Question 22

A 32 y/o female nonsmoker is evaluated for slowly progressive dyspnea. For the last 6 months she has experienced progressive exertional dyspnea, exertional chest pressure, and dry cough. She is now short of breath when climbing one flight of stairs. She has no fever or weight loss. She reports one episode of a painful, raised, erythematous lesion on the anterior right shin accompanied by fever and ankle pain 6 months ago that resolved spontaneously after 3 weeks. Physical exam is normal. PFTs reveal FEV1 75%, FVC 88%, FEV1/FVC 68%, TLC 78%, and RV 70%. CXR appears “cloudy” in some areas but is otherwise normal. Which of the following is the most likely diagnosis?

A. Chronic hypersensitivity pneumonitis
B. Lymphangioleiomyomatosis
C. Respiratory bronchiolitis-associated interstitial lung disease
D. Sarcoidosis

Answer 22

D. Sarcoidosis

Question 23

A 65 y/o man is evaluated for a 4-month history of gradually progressive SOB. Initially, symptoms were only present with exertion, but now they occur at rest. He also has an occasional productive cough. He has a 30-pack year hx of smoking and quit 10 years ago. He worked as a “chipper” in a shipyard where he had extensive and unprotected exposure to asbestos 20 years ago. Which of the following diagnostic tests should be done next?

A. Antinuclear antibody, rheumatoid factor, and ESR
B. Open lung biopsy
C. Transbronchial lung biopsy
D. Endobronchial US with biopsy (EBUS)
E. No further testing

Answer 23

E. No further testing

We know he has asbestosis!