Interstitial Lung Diseases

Question 1

IPF Presentation

Answer 1

• Demo - males 50-70 yo
• Presentation - dyspnea on exertion getting worse; non-productive cough; loud velcro-like crackles on inspiration (heard at bases); clubbing

Question 2

IPF Imaging / Dx

Answer 2

• Imaging - (“usual interstitial pneumonia pattern”) - reticulonodular infiltrates esp at bases (X-ray) and sub-pleural honeycombing and traction bronchiectasis (CT)
• Dx - r/o other causes then see above CT

Question 3

IPF Histo (3)

Answer 3

1- geographic heterogeneity (honeycombing right next to area of normal lung)

2- temporal heterogeneity (areas of chronic scarring next to areas of active inflammation)

3- fibroblastic foci (new fibrosis - see fibroblasts undergoing replication)

Question 4

IPF PFTs

Answer 4

• dec FEV1, dec FVC, dec diffusion capacity (which leads to inc A-a gradient)

Question 5

IPF Prognosis and Tx

Answer 5

• Prognosis - POOR; unpredicatable; step-wise dec in lung function but may have sudden exacerbation –> death
• Tx - NO USEFUL MEDS (inc FVC by only 150 mL compared to placebo)

**refer for lung transplant early

Question 6

Silicosis

Answer 6

-Silica (miners, quarry, stonework, foundry, pulverizers)

• Simple - few symp
• Complex - fibrosis, nodules coalesce, progress to resp failure (susceptible to Tb)
• Acute - rare; rapid fibrosis

APEX

• Classic onion-like nodules (concentric fibers)
• Lymph nodes w/ egg-shell calcifications on X-ray
• Non-specific fibrosis

Question 7

Asbestos

Answer 7

• Asbestosis (if causative) or Asbestos-related Pleural Disease
• Asbestos - used for hear resistance
• Smoking + asbestos = synergistic risk of bronch carcinoma
• Asbestos alone –> risk of mesothelioma (pleural tumor)

BASES

• very similar to IPF on imaging and histo
• Hallmark = asbestos bodies (Ferruginous bodies); not always present

Question 8

Coal Worker’s Pneumoconiosis

Answer 8

-Coal dust in lungs

• Simple- few symptoms; cough and sputum
• Complicated - nodules coalesce (inc risk of Tb)

APEX
-Coal Macule (dust-laden macrophages + fibroblasts) in resp bronchioles

Question 9

Berylliosis

Answer 9

• Mining, precision machinery, nuclear and electronics, computer components (microcircuits), guidance and navigation systems
• Acute or chronic

APEX
-Granulomas form

Question 10

Sarcoidosis

Answer 10

-Th1 response –> granuloma formation in multiple organs (lungs, eyes - uveitis, hilar nodes, liver)

Tx

• High rate of spont remission
• 1st line = corticosteroids

Stage 1 - see balanced hilar lymphadenopathy (on both sides of X-ray)
Stage 2 - lymph and lung infiltrates
Stage 3 - just lung involvement seen
Stage 4 - FIBROSIS on X-ray

-Trans-brachial biopsy (thru mouth) - non-caseating granulomatous inflammation along broncho-vascular bundles (NO NECROSIS)

Question 11

Lofgren’s Syndrome

Answer 11

• arthralgias
• erythema nodosum - painful red nodules on anterior tibia
• uveitis
• stage 1 sarcoidosis on chest X-ray