Interstitial Lung Diseases

Question 1

What types of tissue are destroyed in Interstitial Lung Diseases?

Answer 1

Alveolar walls
Lung parenchyma
Interstitium (tissue b/t alveoli)

Question 2

Interstitial Lung Disease will have what kind of pattern on PFT? Obstructive or Restrictive? Why?

Answer 2

Restrictive pattern

Inability to bring air in due to increased alveolar damage associated w/ fibrotic remodeling and/or inflammation

Question 3

Which specific gene is associated with ILD?

Answer 3

MUC5B gene

Question 4

What are some causes or risk factors of ACUTE ILD?

Answer 4

Majority of cases are IDIOPATHIC
Allergies: PCN, fungi, helminthic infxn, extrinsic allergic aveolitis
Toxins: Amiodarone, fumes, or chlorine gas

Question 5

What are some causes or risk factors of CHRONIC ILD?

Answer 5

Idiopathic Pulm Fibrosis
Inorganic Dusts: Silicosis, Asbestosis, Coal Workers’ Pneumoconiosis)
Organic Dusts: Bacteria or animal proteins (i.e. bird fancier’s lung)

Question 6

What are some of the common presenting factors of ILD’s?

Answer 6

Dyspnea: MC
Non-productive (dry) cough
Bibasilar, end-inspiratory crackles
Pleuritic tightness/heaviness
Wheezing
Pulmonary HTN
Clubbing 
Cyanosis
Weight loss or anorexia
Fatigue

Question 7

What blood tests would you order for a PT suspected of ILD?

Lab tests if abnormal would indicate which diseases?

Answer 7

CBC with diff:
Eosinophilia: Sarcoidosis, eosinophilic pneumonia, drug induced ILD, vasculitis
Hemolytic Anemia:
Normocytic Anemia: Alveolar hemorrhage

ESR (Sed Rate): Vasculitis or collagen vasc. Dz (active Sarcoidosis)

ANA positive: SLE, rheumatoid arthritis (collagen vasc. Dz’s)

Antineutrophil Cytoplasmic Antibody (ANCA):

Question 8

If a CXR is ordered on a PT with suspected ILD; what would you be looking for?

Answer 8

Hilar/mediastinal lymphadenopathy
Pleural effusion / Pleural Thickening
Ground Glass (reversible)
Honeycombing (irreversible)

Question 9

Spirometry of a PT suffering from late stage ILD would yield what kind of expected results?

Answer 9

Reduced FVC, FEV1, TLC, FRC, RV, and DLCO

NORMAL FEV1/FVC ratio because both values are decreased together leaving ratio unchanged

These values are observed because the lungs are stiff and fibrotic (very noncompliant and unable to bring air in)

Question 10

A Bronchoalveolar Lavage is performed as a diagnostic study on a PT suspected to have ILD; what information will the T-helper: Suppressor ratio provide you with?

Answer 10

Increased Thelper:Suppresor ratio –> Sarcoidosis

Decreased THelper:Suppresor ratio –> Hypersensitivity Pneumonitis

Question 11

What are the stages of Sarcoidosis?

Answer 11

0: Normal
Stage I: Hilar adenopathy
Stage II: Hilar adenopathy + parenchymal involvement
Stage III: Parenchymal involvement alone

Question 12

Sarcoidosis may also present/clinically manifest into what other conditions?

Answer 12

Iritis

Uveitis

Question 13

What is the most toxic particulate?

Answer 13

Silica

Question 14

What is the most common presenting complaint with ILD i.e. Pulmonary Fibrosis?

Answer 14

Dyspnea (b/c restrictive and difficulty taking air in)

Question 15

Ground glass infiltrates are visible on CXR; what does this mean for the PT vs. if the findings were honeycombing?

Answer 15

Ground-glass infiltrates indicates Dz progression is reversible

Honeycombing is not reversible.

Question 16

What is the clinical presentation of Idiopathic Pulmonary Fibrosis?

Answer 16

MC in Men (40-50) smokers
Ground glass infiltrates or Honeycombing
Clubbing
Reduced lung vol. (Restrictive PFT findings)
Decreased DLCO

Question 17

How would you Dx and Tx Pulmonary Fibrosis?

Answer 17

CXR and PFTs

N-acetylcysteine (mucolytic)
Prednisone (6-12wks)
Cyclophosphamide (Cytoxan)
Lung transplant only definitive cure