Pulmonary Fibrosis

Question 1

Incidence of idiopathic pulmonary fibrosis?

Answer 1

Estimated to range from 3 to 9 cases per 100,000 per year in Europe and North America

Question 2

What is the aetiology of idiopathic pulmonary fibrosis?

Answer 2

Although aetiology is unknown, cigarette smoking and certain environmental exposures (organic and inorganic dust exposure) have been implicated in the development of the disease.

Question 3

What risk factors are implicated with idiopathic pulmonary fibrosis?

Answer 3

Strong:

• Advanced age: commonly >50yrs
• Male sex
• FHx
• Cigarette smoking

Weak:

• Organic and inorganic dust exposure
• Gastro-oesophageal reflux
• Infection
• Diabetes

Question 4

What symptoms would be typical of an idiopathic pulmonary fibrosis history?

Answer 4

Non-productive cough

Exertional dyspnoea

Constitutional symptoms e.g. weight loss, malaise, fatigue, arthralgia

Question 5

What signs are typical on examination of a patient with idiopathic pulmonary fibrosis?

Answer 5

Cyanosis

Finger clubbing

Fine, end-inspiratory crepitations at lung bases

Question 6

What differentials should you consider alongside idiopathic pulmonary fibrosis?

Answer 6

Pneumonia

Pulmonary fibrosis of known aetiology:

• Connective tissue disease-associated
• Drug-related

Asbestosis

Sarcoidoisis

Sjogren’s disease

Question 7

How is a diagnosis of idiopathic pulmonary fibrosis usually made?

Answer 7

The diagnosis can be made on clinical grounds when an appropriate history of progressive symptoms (typically dyspnoea and cough) is accompanied by characteristic x-ray findings and restrictive pulmonary physiology & in the absence of findings suggesting alternative diagnosis.

Question 8

How would you investigate pulmonary fibrosis?

Answer 8

Pulmonary function tests: may show restrictive changes.

Imaging:
CXR: results basilar, peripheral, bilateral, asymmetrical, reticular opacities; ↓Lung volume; bilateral lower zone reticulo-nodular shadows; honeycombing (advanced).

High-resolution CT (HRCT): results basilar- and subpleural-predominant areas of increased reticulation, honeycombing, and possible traction bronchiectasis

• Shows similar changes to the CXR
• More sensitive and is essential for diagnosis.
• Can increase the level of diagnostic confidence for IPF and, in certain situations, obviate the need for surgical lung biopsy. 

Question 9

How would you treat pulmonary fibrosis?

Answer 9

Antifibrotic agent (nintedanib and pirfenidone)

Supportive:

• Smoking cessation
• Pulmonary rehab
• Supplemental O2

Clinical trials and lung transplant should be discussed.

High-dose steroids are NOT indicated.