Extrinsic allergic alveolitis + ABPA

Question 1

What is EAA or hypersensitivity pneumonitis?

Answer 1

hypersensitivity reaction which causes widespread inflammation in the alveoli and small airways of the lung

due to hypersensitivity to organic dust

most common is farmers lung

Question 2

Which types of hypersensitivity reactions are involved?

Answer 2

Type III hypersensitivity - immune complex mediated tissue damage

Type 4 hypersensitivity - thought to play a role esp in chronic phase

Question 3

What are examples of EAA conditions? (7)

Answer 3

1. Farmers lung
2. Bird fanciers lung
3. Malt workers lung (aspergillus clavatus)
4. Humidifier fever
5. Mushroom workers
6. Cheeseworkers lungs (aspergillus clavatus + other)
7. wine makers lungs

Question 4

How does EAA present acutely? timeframe?

Answer 4

4-8 hrs after exposure

1. cough
2. dyspnoea
3. fever

Question 5

How does chronic EAA present? timeframe/

Answer 5

weeks to months after exposure

1. productive cough
2. dyspnoea
3. lethargy
4. anorexia and weight loss
5. type 1 resp failure
6. clubbing

Question 6

What investigations would you do for EAA and what would you expect to see?

Answer 6

1. Bloods: FBC (neutrophils high, NO EOSINOPHILS), ESR raised, serum IgG antibodies. ABGs
2. CXR: upper/midzone mottling/consolidation/fibrosis (groundglass nodules). rarely hilar lympadenopathy
3. Lung function tests: restrictive defect
4. Bronchoalveolar lavage: increased lymphocytes

Question 7

How do you manage acute EAA

Answer 7

1. oxygen 35-60%

2. prednisolone

Question 8

How do you manage chronic EAA

Answer 8

1. avoid precipitating factors or wear facemasks and positive pressure helmet
2. long term steroids
3. compensation

Question 9

What is allergic bronchopulmonary aspergillosis and what is strongly associated features?

Answer 9

• allergic reaction to aspergillosis spores

- in exam usually associated with bronchiectasis and eosinophilia

Question 10

Who does allergic bronchopulmonary aspergillosis commonly affect?

Answer 10

• asthama

- CF

Question 11

How does allergic bronchopulmonary aspergillosis present?

Answer 11

• bronchoconstriction - wheeze, dyspnoea, cough

- bronchiectasis

Question 12

what do investigations show in allergic bronchopulmonary aspergillosis

Answer 12

1. esinophilia
2. bronchiectasis, flitting consolidation
3. +ve RAST test for aspergillus
4. +ve IgG
5. raised IgE

Question 13

What is the management of allergic bronchopulmonary aspergillosis?

Answer 13

1. oral glucocorticoids

2. itraconozole