Allergy

Question 1

What is an allergy?

Answer 1

Hypersensitivity disorders the immune system

Question 2

What does an allergy cause?

Answer 2

Inappropriate or exaggerated immune reaction, causing damage to the host

Question 3

What do allergic reactions normally occur against?

Answer 3

Allergens- harmless environmental substances, usually proteins

Question 4

What causes variation in the symptoms of an allergy?

Answer 4

Individual
Allergen
Mode of introduction

Question 5

What is an allergic reaction of the skin called?

Answer 5

Urticaria/angiodema

Question 6

What is an allergic reaction of the upper respiratory tract called?

Answer 6

Rhinitis

Question 7

What is an allergy of the lower respiratory tract called?

Answer 7

Asthma

Question 8

What is a systemic allergic reaction called?

Answer 8

Anaphylaxis

Question 9

What is the pathology of an allergy?

Answer 9

Hypersensitivity due to IgE antibodies

Question 10

What happens in the sensitisation stage of a hypersensitivity reaction?

Answer 10

Plasma cells produce IgE against allergen, which then bind to mast cells

Question 11

What happens in the re-exposure phase of a hypersensitivity reaction?

Answer 11

IgE activated and mast cells degranulate and causes allergic reaction

Question 12

What does mast cell degranulation release?

Answer 12

Histamine
Leukotrines
Prostaglandins
Chromotactic factors

Question 13

What does mast cell degranulation physiologically cause?

Answer 13

Vasodilation
Vascular permeability
Smooth muscle contraction
Leukocyte infiltration

Question 14

What is the late phase response?

Answer 14

Migration of leukocytes to initial site 2-4 hours after insult

Question 15

What are the risk factors for an allergy?

Answer 15

Hereditary, race, age
Exposure to infectious disease as child, pollution, allergen levels, dietary changes
Flour, latex, wood dust

Question 16

What is allergic rhinitis?

Answer 16

Allergic inflammation of nasal airways

Question 17

When does allergic rhinitis occur?

Answer 17

Allergen inhaled by individual with sensitised immune system

Question 18

What are the risk factors for allergic rhinitis?

Answer 18

Atopy, family history, 1st born

Exposure to infectious disease as child, pollution, allergen levels, dietary changes

Question 19

What are the immediate symptoms of allergic rhinitis?

Answer 19

Sneezing
Itch
Nasal blockage
Rhinorrhoea

Question 20

What are the late symptoms of allergic rhinitis?

Answer 20

Chronic obstruction
Hyposmia
Hyperreactivity

Question 21

What are the classifications of allergic rhinitis?

Answer 21

Intermittent vs persistent

Mild vs moderate/severe

Question 22

What is classified as intermittent allergic rhinitis?

Answer 22

Symptoms for < 4 days per week for < 4 consecutive weeks

Question 23

What is classified as persistent rhinitis?

Answer 23

Symptoms for > 4 days a week for > 4 weeks

Question 24

What is classified as mild rhinitis?

Answer 24

Symptoms present but not troublesome

Question 25

What is classified as moderate/persistent rhinitis?

Answer 25

Sleep disturbance Impairment of daily activities, school or work Troublesome symptoms

Question 26

How is an allergy diagnosed?

Answer 26

``` Skin test RAST Total serum IgE Nasal allergen challenge Nasal cytology ```

Question 27

What is tested in a skin test?

Answer 27

Response to known allergens

Question 28

What is tested in RAST?

Answer 28

Presence and levels of allergen specific IgE

Question 29

What is a normal and hypersensitive IgE level?

Answer 29

``` <0.35= normal >0.35= hypersensitivity ```

Question 30

How is an allergy treated?

Answer 30

Allergen avoidance Pharmacologically Possible immunotherapy and surgery

Question 31

How can an allergy be treated pharmacologically?

Answer 31

``` Topical intranasal steroids Systemc steroids Antihistamines Sodium cromoglycate Allergen immunotherapy Anti IgE ```