Allergy in the Lung

Question 1

What is intolerance?

Answer 1

The inability to cope with normally acceptable conditions or exposures.

Question 2

What is allergy?

Answer 2

Allergy is an immune system mediated intolerance

Question 3

How is allergy different from hyper-reactivity?

Answer 3

Hyper-reactivity is a physiological reaction which occurs in all people when there is a high exposure dose but occurs in people with hyper-reactivity at a lower exposure dose. Allergy does not normally affect people, no matter the dose, but patient’s with allergy will react no matter the dose

Question 4

What investigation is useful in allergy affecting the airways?

Answer 4

Spirometry

Question 5

What symptom will result from allergy of the airways?

Answer 5

Wheeze

Stridor

Question 6

Allergy at what point in the airways would result in stridor rather than wheeze?

Answer 6

Wheeze when airways/bronchioles are narrowed

Stridor results from narrowing in the airways above the vocal cords

Question 7

Give an example of extra-thoracic disease which can cause stridor?

Answer 7

Laryngeal oedema (thyroid, scarring, epiglotitis)

Question 8

Define asthma

Answer 8

Reversible airflow obstruction caused by inflammation and has an allergic component.

Question 9

What are the common triggers of asthma?

Answer 9

Cold
Exercise
Animal dander
Dust

Question 10

What are the symptoms of asthma?

Answer 10

Cough
Wheeze
Breathlessness
Nocturnal symptoms and diurnal variation

Question 11

Describe the bronchial challenge test in asthma

Answer 11

Assess bronchial huperresponsiveness to histamine using either histamine/metacholine or indirectly using mannitol

Question 12

How can a suspected cat allergy in asthma be determined?

Answer 12

Skin prick test

Or blood antigen test but this is less specific

Question 13

What changes are seen histologically in asthma?

Answer 13

Smooth muscle hypertrophy

Question 14

What are the possible treatments of asthma?

Answer 14

Anti IgE biological therapy
Corticosteroids
Anti-leukotriene drugs
Bronchodilators

Question 15

What treatments of asthma are currently in development?

Answer 15

Immunotherapies
Biological therapies against IL-5 and IL-13
Thermoplasty
Nerve ablation

Question 16

What type of hypersensitivity reaction is responsible for allergic disease in the lung parenchyma?

Answer 16

Type 3

Question 17

What investigations are useful in allergic disease of the lung parenchyma?

Answer 17

CXR

Other imaging

Question 18

What can trigger extrinsic allergic alveolitits?

Answer 18

Bird dander
Mushrooms
Farmer's lung
Aspergillus
Cheese workers
Wheat weevil
Mollusc shell workers
Malt worker's lung
Humdifier lung

Question 19

What are the symptoms of acute allergy of the lung parenchyma?

Answer 19

Wheeze
Cough
Fever
Chills
Headache
Myalgia
Malaise
Fatigue

Question 20

How does allergic disease of the lung parenchyma result in hyperaemia?

Answer 20

Thickening of the septal and filling of the alveolus with fluid. This causes a loss of oxygen leading to hyperaemia

Question 21

What sign of allergic disease of the lung parenchyma can be seen on CXR?

Answer 21

Air space shadowing

Question 22

How is allergic disease of the lung parenchyma managed?

Answer 22

Avoidance of the trigger

Corticosteroids