Arfoosh: Diffuse Parenchymal Lung Diseases

Question 1

What three diseases does this lecture focus on? (try to think of key factors of each)

Answer 1

• Idiopathic Pulmonary Fibrosis
• Hypersensitivity pneumonitis (farmer’s lung, bird fancier’s lung)
• Sarcoidosis (idiopathic)

Question 2

What features categorize a disease as parenchymal lung disease?

Answer 2

A disease that predominantly affects interstitium or parenchyma of the lung; share certain radiologic, pathologic, and physiologic features

Question 3

What is the pathophysiology of parenchymal lung disease?

Answer 3

repeated injury to interstitium –> repeat attempts to repair –> healing with fibrosis in a genetically predisposed patient –> permanent impairment of lung function

Question 4

What is the clinical manifestation in parenchymal lung disease?

Answer 4

• progressive dyspnea
• NON-productive cough
• fatigue
• tachypnea

Question 5

What diagnostic clues will you see in your patient?

Answer 5

• crackels
• mild inspiratory SQUEAK
• right ventricular strain
• digital clubbing
• extra pulmonary signs

Question 6

**What imaging will you use in diagnosing parenchymal lung disease?

Answer 6

**High-resolution CT scan (HRCT) - shows ground Glass Changes, Septal thickening and honey combing

Question 7

What will your PFT show in a patient with parenchymal lung diseases?
(Idiopathic Pulmonary Fibrosis, Hypersensitivity pneumonitis, Sarcoidosis)

Answer 7

FEV1, FVC decreased, but
FEV1/FVC ratio preserved
TLC decreased
DLCO decreased

Question 8

What will your findings be in a patient with idiopathic pulmonary fibrosis?

Answer 8

crackles, clubbing, and hypoxemia on physical exam

HRCT: UIP pattern: basal, subpleural predominance; reticular changes; HONEYCOMBING with traction bronchiectasis

Question 9

What is the hallmark finding in a patient with sarcoidosis?

Answer 9

Granulomatous (noncaseating)

Question 10

What population is sarcoidosis found in?

Answer 10

black women ages 20-40 in US; highest in northern europe

Question 11

What other organs can sarcoidosis affect?

Answer 11

eyes, skin, liver/spleen

Question 12

If your patient has Lofgren’s Syndrome in Sarcoidosis, what other symptoms will you see?

Answer 12

Erythema nodosum (these lesions should not be biopsied), BHA (bilateral hilar adenopathy), fever, migratory arthralgias

Question 13

Describe the 4 stages of pulmonary sarcoidosis.

Answer 13

I: BHA
II: BHA and reticular opacities
III. reticular opacities (upper lung zones) with shrinking hilar nodes
IV: reticular opacities with evidence of volume loss and progressing fibrosis

Question 14

What is the preferred way to diagnose sarcoidosis?

What is the preferred imaging in dx?

Answer 14

biopsy; PET scan

Question 15

What is the tx in sarcoidosis?

Answer 15

(wait 6 months before starting)
- Frist line: corticosteroids
- steroid sparing: methotrexate
- treat for 6-12m
- hydroxychloroquine for cutaneous disease
(no sarcoidosis meds are FDA-approved)

Question 16

What will the HRCT of a patient with hypersensitivity pneumonitis look like?

Answer 16

White dots laterally; Ground Glass changes, usually sparing the pleural

Question 17

What occurs in hypersensitivity pneumonitis?

Answer 17

Arfoosh explains it’s like when an allergen gets in your nose and you get nasal congestion, but these allergens in hypersensitivity pneumonitis are smaller and get into your lungs. So you have diffuse inflammation of lung parenchyma.

Question 18

Treatment of hypersensitivity pneumonitis?

Answer 18

Avoid the allergen!
Fro severely symptomatic patients: glucocorticoid tx with 0.5 to 1 mg of Prednisone per kg of IDEAL body weight (up to 60 mg/day). Taper after 4-6 weeks.