Interstitial lung diseases

Question 1

What is the definition of ILD

Answer 1

Inflammatory process involving alveolar wall leading to irreversible fibrosis, distortion of lung architecture, and impaired gas exchange

Question 2

What are the six general categories of interstitial lung disease

Answer 2

1. ) Environmental lung disease
2. ) ILD with granulomas
3. ) Alveolar filling disease
4. ) Hypersensitivity lung disease
5. ) Drug induced - amiodarone, nitrofurantoin, bleomycin, phenytoin
6. ) Miscellaneous

Question 3

What are the causes of environmental lung disease

Answer 3

1. ) Coal worker’s pneumoconiosis
2. ) Silicosis
3. ) Beryillosis
4. ) Asbesosis

Question 4

What are causes of ILD associated with granulomas

Answer 4

1. ) Sarcoidosis
2. ) Histiocytosis X
3. ) Wegener’s granulomatosis
4. ) Churg-Strauss syndrome

Question 5

What are causes of ILD associated with alveolar filling disease

Answer 5

1. ) Goodpasture syndrome
2. ) Idiopathic pulmonary hemosiderosis
3. ) Alveolar proteinosis

Question 6

What are the two causes of hypersensitivity lung disease

Answer 6

1. ) Hypersensitivity pneumonitis

2. ) Eosinophilic pneumonitis

Question 7

What are other miscellaneous causes of ILD

Answer 7

1. ) Idiopathic pulmonary fibrosis
2. ) Bronchiolitis obliterans organizing pneumonia (BOOP)
3. ) Connective tissue diseases: Rheumatoid arthritis, scleroderma, SLE, mixed connective tissue disease
4. ) ARDS
5. ) Radiation pneumonitis

Question 8

What are symptoms and signs of ILD

Answer 8

Symptoms

1. ) Dyspnea
2. ) Cough that is nonproductive
3. ) Fatigue

Signs

1. ) Rales at the bases
2. ) Digital clubbing: Increased convexity of the nail due to increase in soft tissue
3. ) Pulmonary HTN and cyanosis in advanced disease

Question 9

What is a honeycomb lung

Answer 9

Scarred shrunken lung as an end stage finding with poor prognosis with dilated air spaces, fibrous scars in interstitum

Question 10

What is the only definitive way to find out if someone has ILD

Answer 10

Clinical findings and imaging studies are non-specific, tissue biopsy is the only way

Fiberoptic bronchoscopy with transbronchial biopsy: Limited amount of tissue obtained

2. ) open lung biopsy
3. ) video assisted thoracoscopic lung biopsy

Question 11

What do you see on a CXR of interstitial lung diseases

Answer 11

Reticular, reticulonodular, ground glass, and honeycombing - remember these

Question 12

What do you see on the PFT’s of someone with ILD

Answer 12

Restrictive pattern with low diffusing capacity

Question 13

What is the definitive diagnosis for ILD

Answer 13

1. ) Fiberoptic bronchoscopy with transbronchial biopsy - limited because can’t get big enough tissue sample
2. ) Open lung biopsy
3. ) Video assisted thoracoscopic lung biopsy

Urinalysis also assists with diagnosis such as with goodpasture’s syndrome and Wegener’s granulomatosis

Question 14

What are the interstitial diseases associated with granulomas

Answer 14

1. ) Sarcoidosis
2. ) Histiocytosis X
3. ) Wegener’s
4. ) Churg Strauss syndrome

Question 15

Sarcoidosis is a noncaseating granulomatous disease that has granulomas in almost every system. What are the constitutional, lung, skin, and eye symptoms

Answer 15

1. ) Constitutional: Malaise, fever, anorexia, weight loss
2. ) Lungs: Dry cough, dyspnea with exercise
3. ) Skin: Erythema nodosum
4. ) Anterior uveitis: 75%, posterior 25%

Question 16

Sarcoidosis is a noncaseating granulomatous disease that has granulomas in almost every system. What are the heart, MSK, and nervous system findings

Answer 16

5. ) Heart - arrhythmias
6. ) MSK: Arthralgias and arthritis
7. ) Nervous system: Bells palsy, peripheral neuropathy

Question 17

How do you diagnose sarcoidosis

Answer 17

Based on clinical, radiographic, and histological findings

1. ) CXR: Bilateral hilar adenopathy
2. ) ACE elevation - only 50-80% of patients
3. ) Hypercalciuria and hypercalcemia
4. ) PFTS

Definitive: Biopsy

Question 18

What are the stages of sarcoidosis

Answer 18

Stage 1: Bilateral hilar adenopathy without parenchymal infiltrates
Stage 2: Both
Stage 3: Parenchymal infiltrates without bilateral hilar adenopathy
Stage 4: Pulmonary fibrosis

Question 19

What are the treatment choices for sarcoidosis

Answer 19

Most cases resolve spontaneously within 2 years without treatment

First line: Systemicc steroids
Second line: Methotrexate

Question 20

What is histiocytosis

Answer 20

Abnormal proliferation of histiocytes in the lung (related to langerhan ells of the skin) - 90% are cigarette smokers

Can present with pneumothorax, lytic bone lesions, and diabetes insipidus

Question 21

What is Wegener’s disease

Answer 21

Necrotizing granulomatous vasculitis affecting vessels of lungs, kidneys, upper airways

They easily get upper and lower respiratory infections, glomerulonephritis, and pulmonary nodules

Associated with c-anca

Question 22

What is churg strauss syndrome

Answer 22

Another granulomatous vasculitis like Wegener’s but now seen in patients with asthma

These people have pulmonary infiltrates, rash, and eosinophilia (eosinophilia especially in the blood)

Associated with p-anca

Question 23

What are the four environmental pneumoconioses

Answer 23

1. ) Coal worker’s
2. ) Asbestosis
3. ) Silicosis
4. ) Berylliosis

Question 24

What is the pathophysiology of pneumoconioses

Answer 24

Accumulation of non-organic dust in the lungs and the tissue reacting to it

Question 25

What are some clinical pearls of asbestosis

Answer 25

Predilection for lower lobes with increased risk of bronchogenic carcinoma and malignant mesothelioma

CXR shows hazy infiltrates with bilateral linear opacities

No treatment

Question 26

What are some clinical pearls of silicosis

Answer 26

Localized and nodular peribronchial fibrosis that occurs more in upper lobes (asbestosis is widespread and in lower lobes)

Happens in mining, stone cutting, and glass manufacturing

Increased risk of TB

Question 27

What are some clinical pearls of berylliosis

Answer 27

Acute form: Diffuse pneumonitis
Chronic form: Like sarcoidosis with hypercalcemia too

Test: Beryllium lymphocyte proliferation test