Interstitial Lung Disease

Question 1

What is interstitial lung disease?

Answer 1

Any disease process affecting lung interstitium

Question 2

What is pulmonary interstitium made of?

Answer 2

Alveolar lining cells - type 1 & 2

Thin elastin-rich connective tissue with capillary blood vessels

Question 3

How can early and late stage be differentiated?

Answer 3

early - alveolitis

late - fibrosis

Question 4

What are the symptoms of ILD?

Answer 4

• breathlessness
• dry cough
  Due to hypoxia and cardiac failure

Question 5

State two causes of ILD

Answer 5

• environmental (minerals, drugs, radiation)

- idiopathic

Question 6

Describe the three types of ILD

Answer 6

Acute - viral or inhalation of toxic substance
Episodic - comes and goes
Chronic - part of system disease, exposure to agent, idiopathic, sarcoidosis or pneumoconiosis

Question 7

What type of sensitivity reaction is sarcoidosis? What is the cause?

Answer 7

Type 4 involving granulomas

Unknown aetiology

Question 8

Which population has a higher incidence of sarcoidosis?

Answer 8

African americans & people of caribbean origin

Question 9

Where in the body can be affected by sarcoidosis?

Answer 9

• lungs
• lymph nodes
• joints
• liver
• skin (erythema nodosum)
• eyes (uveitis)

Question 10

What kind of granuloma is sarcoidosis?

Answer 10

Non caseating

Question 11

Describe the symptoms of acute sarcoidosis

Answer 11

• erythema nodosum
• bilateral hilar lymphadenopathy
• arthritis
• uveitis
• parotitis
• fever

Question 12

Describe the symptoms of chronic sarcoidosis

Answer 12

• lung infiltrates
• skin infiltrates
• peripheral lymphadenopathy
• hypercalcaemia (abnormal vitamin D metabolism in granulomas)

Question 13

What investigations should be done on a patient with suspected sarcoidosis? How can it be treated?

Answer 13

• CXR
• CT scan
• tissue biopsy
• pulmonary function test
• blood test
  acute - self limiting
  chronic - oral steroids if affecting vital organ if unsuccessful immunosuppressive drugs are required

Question 14

What type of hypersensitivity is extrinsic allergic alveolitis?

Answer 14

type 3 - reaction to antigen lymphocytic alveolitis

Question 15

Describe the aetiology of EAA

Answer 15

• thermophilic actinomycetes (mould on hay)
• avian antigens
• drugs
• idiopathic

Question 16

What are the symptoms and treatment of acute EAA?

Answer 16

S - cough, breathlessness, fever, myalgia

T - oxygen, steroid, antigen avoidance

Question 17

What are the signs and symptoms of chronic EAA?

Answer 17

cough, breathlessness, crackles and fibrosis in upper lobes due to inhalation

Question 18

Name three investigations that should be done on a patient with suspected chronic EAA

Answer 18

• Pulmonary function tests (low FEV1/FVC)
• CXR
• lung biopsy

Question 19

What is the diagnosis and treatment of chronic EAA?

Answer 19

D - history, IgE antibodies to guilty antigen

T - remove antigen and oral steroids for breathlessness

Question 20

Describe the aetiology of idiopathic pulmonary fibrosis

Answer 20

It is unknown but the lungs develop an imbalance in their repair system

Question 21

Name four secondary causes of IPF

Answer 21

• rheumatoid
• systemic sclerosis
• asbestos
• drugs

Question 22

What drugs can cause IPF

Answer 22

amiodarone 
busulphan
bleomycin 
pencillamine 
nitrofutatoin (for recurrent UTIs)
methotrexate

Question 23

Describe the presentation, examination and investigation findings of IPF

Answer 23

P - progressive breathlessness and dry cough
E - clubbing, bilateral fine inspiratory crackles
I - restrictive defect on PFTS (reduced FEV1/FVC)

Question 24

What will be found on CXR and CT for patients with IPF?

Answer 24

CXR - bilateral infiltrates

CT - reticulonodular fibrotic shadowing, worse at the lung bases. Honeycombing cystic changes traction bronchiectasis.

Question 25

Describe the pathology of IPF

Answer 25

usual interstitial pneumonia pattern heterogenous fibrosis in alveolar wall with fibroblastic foci

Question 26

What is the treatment for IPF

Answer 26

• new antibiotics
• oxygen if hypoxic
• lung transplant

Question 27

Describe coal workers pneumoconiosis

Answer 27

lung disease caused by mineral dust exposure

depends on; particle size, reactivity of particle, clearance of particle, host response

Question 28

What happens as a result of coal dust and smoking?

Answer 28

Chronic bronchitis

Question 29

What is simple pneumoconiosis?

Answer 29

CXR abnormality but no lung impairment (often associated with COPD

Question 30

What is complicated pneumoconiosis?

Answer 30

progressive massive fibrosis (restrictive pattern with breathlessness)

Question 31

Explain Caplan’s syndrome

Answer 31

rheumatoid pneumoconiosis - pulmonary nodules cavitate

Question 32

Describe a classic CXR of silicosis

Answer 32

egg shell classification of hilar nodules

Question 33

What four pleural diseases can asbestos cause?

Answer 33

• benign pleural plaques
• acute asbestos pleuritis
• pleural effusion & diffuse pleural thickening
• malignant mesothelioma

Question 34

What two other diseases can asbestos cause?

Answer 34

• pulmonary fibrosis (heavy prolonged exposure. Diffuse PF & restrictive defect. Asbestos bodies in sputum and fibres in biopsy)
• bronchial carcinoma (asbestos multiplies risk in smokers)