Intersticium, Pleura and Chest disease

Question 1

What is the interstitial space

Answer 1

Potential space between alveolar cells and capillary basement membrane

Question 2

Functions of the interstitial space

Answer 2

Structural support
Immune function
Controls alveolar growth

Question 3

What structural changes occur in the lungs in interstitial disease

Answer 3

Intersticium becomes apparent as it contains collagen, cells and fluid
Also affects acini, alveoli lumen, bronchioles, epithelia, endothelia, mesenchyme and macrophages
Inflammatory cells are recruited

Question 4

How does interstitial disease affect lung function

Answer 4

Fibrosis decreases lung compliance, decreases perfusion and increases diffusion distance
It is a restrictive airflow disorder that causes type 2 respiratory failure

Question 5

Symptoms and signs of interstitial disease

Answer 5

Symptoms: chronic dyspnoea, chronic cough
Signs: tachypnoea, tachycardia, bilateral reduce chest expansion, cyanosis, signs of right sided heart failure and clubbing in idiopathic pulmonary fibrosis

Question 6

Broad causes of interstitial lung disease

Answer 6

Occupational
Treatment related
Connective tissue disorders
Immunological
Idiopathic

Question 7

What are the occupational causes of interstitial lung disease

Answer 7

Asbestos
Silicosis
Coal workers pneumoconiosis

Question 8

What can asbestos cause and what look like on a CXR

Answer 8

Mesothelioma
Bronchogenic cancers
Asbestosis
On a CXR - asbestos plaques (benign irregular mass of calcified asbestos)

Question 9

What drugs can cause interstitial lung disease and what do each treat

Answer 9

Methotrexate - RA
Bleomycin - lymphoma
Amiadarone - arrhythmias 
Nitrofurantoin - UTIs 
Chemotherapy and radiation - cancer

Question 10

What connective tissue disorders can cause interstitial lung disease

Answer 10

RA
Scleroderma 
Sjogren's syndrome  
Polymyositis 
Systemic lupus erythrematosis

Question 11

What immunological disorders can cause interstitial lung disease

Answer 11

Sarcoidosis

Extrinsic allergic alveolitis

Question 12

What is sarcoidosis

Answer 12

Non caseating granulomas, usually in the lungs

Alveoli contain macrophages and lymphocytes

Question 13

What demographics does sarcoidosis occur in

Answer 13

Female

Afro-Caribbean and Asians

Question 14

How do you confirm sarcoidosis

Answer 14

Biopsy lymph nodes to distinguish sarcoidosis (non caseating) and TB (caseating)

Question 15

Treatment for sarcoidosis

Answer 15

No treatment

Steroids

Question 16

What are the types of extrinsic allergic alveolitis

Answer 16

Acute - farmer’s lung

Chronic - bird fancier’s lung

Question 17

Cause and symptoms of farmer’s lung

Answer 17

Inhalation of actinomycetes in mouldy hay

Symptoms - dry cough, breathlessness on exertion, wheeze, inspiratory crackles

Question 18

Cause and symptoms of bird fancier’s lung

Answer 18

Long term pigeon exposure

Symptoms - extreme malaise, dry cough, chronic breathlessness, inspiratory crackles

Question 19

Describe idiopathic pulmonary fibrosis

Answer 19

Increased activation of alveolar macrophages which attracts neutrophils and eosinophils, leading to tissue damage (release of ROS and hydrolytic enzymes)
Fibrosis occurs to repair damage

Question 20

Symptoms and prognosis of idiopathic pulmonary fibrosis

Answer 20

Progressive SOB
Cough
Clubbing
Poor prognosis - 3 years

Question 21

Treatment of idiopathic pulmonary fibrosis

Answer 21

High dose oral steroids

Antifibrotics

Question 22

CXR appearance in idiopathic pulmonary fibrosis

Answer 22

Small lungs
Micro nodular shadowing in lower lobes
Ragged heart borders

Question 23

CXR appearance in acute extrinsic allergic alveolitis

Answer 23

Diffuse micro nodular infiltrate (denser towards hila)

Question 24

CXR appearance in chronic extrinsic allergic alveolitis

Answer 24

Almost normal but progresses to fibrosis

Question 25

CXR appearance in sarcoidosis

Answer 25

Miliary and nodular shadowing

Diffuse fibrosis

Question 26

What signs and symptoms suggest pleural disease

Answer 26

Pleuritic chest pain
Referred shoulder pain (diaphragmatic pleural irritation)
Pleural rub - creaking noise on auscultation with Resp movements
Pain worse when coughing, sneezing or laughing

Question 27

How is pleural fluid produced and reabsorbed and how much per day

Answer 27

Starling forces at parietal pleura
Absorbed by lymphatics of the parietal pleura
15ml turnover

Question 28

What can cause increased pleural fluid

Answer 28

Increased production - increased interstitial fluid volume, high hydrostatic pressure, increased permeability, low oncotic pressure

Decreased absorption - lymphatic blockage, high systemic venous pressure

Question 29

Causes of haemothorax, chylothorax and empyema

Answer 29

Haemothorax - trauma or iatrogenic
Chylothorax - lymphoma or iatrogenic
Empyema - infection complication (higher risk if immunocompromised or alcoholic)

Question 30

Features of empyema on CT

Answer 30

Loculations - scar tissue dividing chest into smaller cavities

Question 31

Treatment for empyema

Answer 31

Antibiotics

Drainage

Question 32

Describe malignancies of the pleura

Answer 32

Mesothelioma - malignant cancer due to asbestos exposure (almost always pleuritic pain)
Metastasis - most commonly from lung or breast

Question 33

What are some congenital chest wall abnormalities

Answer 33

Kyphosis
Scoliosis
Muscular dystrophy
Pectus excavatum

Question 34

What are some acquired chest wall abnormalities

Answer 34

Trauma
Ankylosing spondylitis 
Motor neurone disease
Polio
Iatrogenic

Question 35

Why does chest muscle weakness increase susceptibility to infection

Answer 35

Poor clearance of secretions because of reduced ventilation