Interstitial Lung Disease

Question 1

What is interstitial lung disease?

Answer 1

An umbrella term for conditions where there is inflammation and fibrosis of the lung tissue. Fibrosis is where normal elastic lung tissue is replaced by inelastic scar tissue.

Question 2

How do you diagnose patients with ILD?

Answer 2

Clinical symptoms
High resolution CT scan
> Ground glass appearance

If diagnosis is unclear, then a lung biopsy can be used to determine pathology.

Question 3

How do you manage patients with ILD?

Answer 3

Supportive management, and where possible, prevent the progression of the disease.

• Remove underlying cause
• Oxygen therapy
• Annual flu and one time pneumococcal vaccine
• Smoking cessation advice
• Physiotherapy and pulmonary rehabilitation
• Advanced care planning and palliative care
• Lung transplant, but this requires an assessment of risks and benefits for the patient.

Question 4

What causes upper zone fibrosis?

Answer 4

CHARTS

C- Coal miner's pneumoconiosis
H- Histiocytosis/ Hypersensitivity pneumonitis 
A- Ankolysing spondylitis 
R - Radiation 
T- Tuberculosis 
S- Sarcodiosis/ Silicosis

Question 5

What causes lower zone fibrosis?

Answer 5

• Idiopathic pulmonary fibrosis
• Connective tissue disorders, apart from ankolysing spondylitis : SLE, rheumatoid arthritis, systemic sclerosis
• Asbestosis
• Drug induced fibrosis - methotrexate, bleomycin, cyclophosphamide, nitrofurantoin, sulfasalazine, amiodarone, busulfan

Question 6

What conditions cause pulmonary fibrosis (causes of secondary pulmonary fibrosis)

Answer 6

• Rheumatoid Arthritis
• Systemic Lupus Erythematosus
• Systemic Sclerosis
• Alpha 1 anti-trypsin deficiency

Question 7

What is idiopathic pulmonary fibrosis?

What are the signs/ symptoms for idiopathic pulmonary fibrosis?

What is the management of idiopathic pulmonary fibrosis?

Answer 7

• Lung fibrosis with no known cause.

- Signs/ Symptoms 
> Insidious onset (> 3months)
> SOB 
> Dry Cough 
> Adults older than 50 years 
> Finger clubbing
> Bibasal fine inspiratory crackles 

Management
- Supportive care
- Two medications have been licensed for slowing down the progression of disease
> Pirfenidone - is an anti-fibrotic and anti-inflammatory
> Nintedanib - is a monoclonal antibody targeting tyrosine kinase receptor.

Question 8

What drugs cause lung fibrosis?

Answer 8

• Amiodarone
• Methotrexate
• Cyclophosphamide
• Bleomycin
• Sulfasalazine
• Nitrofurantoin
• Busulphan

Question 9

What is hypersensitivity pneumonitis (extrinsic allergic alveolitis)?

What investigations need to be carried out for extrinsic allergic alveolitis?

How do you manage hypersensitivity pneumonitis?

What are the different types of extrinsic allergic alveolitis?

Answer 9

Defintion
- Inflammation of the lung (type 3 hypersensitivity reaction) due to exposure to an environmental allergen (organic material).

Investigations

• Imaging - upper/middle lobe fibross
• Bronchoalveolar lavage - lymphocytosis
• Serological assays for IgG antibodies
• Blood - no eosinophilia

Management of hypersenstivity pneumonitis

• Removal of the allergen
• Oxygen therapy
• Corticosteroid therapy

Types of extrinsic allergic alveolitis
> Bird-fancier’s lung –> reaction to bird dropping
> Farmer’s lungs –> reaction to mouldy spores on hay
> Mushroom worker’s lungs –> reaction to specific mushroom antigens
> Malt worker’s lung —> reaction to mould on barley

Question 10

What is cryptogenic organising pneumonia?

How do these patient’s present?

How do you diagnose these patients?

How do you manage these patients?

Answer 10

• Previously regarded as broncholitis obliterates organising pneumonia.
• Similar presentation to pneumonia
  > SOB, cough, fever, lethargy
  > On chest x ray - shows focal consolidation, similar to pneumonia

Diagnosis
- Lung biopsy

Management
- Corticosteroids

Question 11

What is asbestosis?

What lung problems does asbestos cause?

Answer 11

Lower lung lobe fibrosis caused by the inhalation of asbestos.

Lung problems caused by asbestos?
>Pleural plaques - benign, most common form of asbestos related lung problem, 20-40 years latency period.

> Pleural thickening

> Asbestosis - severity of disease is correlated with the length of exposure to asbestos. Large latency period (15-30years). SOB, reduction in exercise tolerance.

> Mesothelioma - can arise even with minimal exposure to asbestos. Crocidolite (blue) asbestos is the most dangerous form. Possible features include progressive dyspnea, chest pain, pleural effusion. Palliative chemotherapy. Median life expectancy: 8-14 months

> Lung cancer- asbestos is a risk factor for lung cancer. Effects synergistic to tobacco.