Allergy

Question 1

What is the incidence of asthma in the UK?

Answer 1

9.4%

Question 2

What is the incidence of allergic rhinitis in the UK?

Answer 2

5.4%

Question 3

What is the incidence of eczema in the UK?

Answer 3

1%

Question 4

What is the incidence of food allergies in the UK?

Answer 4

1-2%

Question 5

What is the incidence of multiple allergies in the UK?

Answer 5

3.7%

Question 6

When did the rapid increase in allergies in the UK begin?

Answer 6

1960s

Question 7

What is the financial cost of treating allergic disorder in a year in Scotland?

Answer 7

£130 million

Question 8

Allergy

Answer 8

-A hypersensitive disorder of the immune system

Question 9

What do allergic reactions occur normally to?

Answer 9

• Harmless environmental substances known as allergens.

- These reactions are acquired

Question 10

Allergic reaction

Answer 10

An exaggerated or inappropriate immune reaction and causes damage to the host

Question 11

What are common allergic reactions?

Answer 11

• Eczema
• Allergic rhinitis
• Asthma
• Food allergies

Question 12

Allergen

Answer 12

Antigen that causes allergic reactions

Question 13

What are allergens usually?

Answer 13

Proteins

Question 14

Systemic or localised symptoms are dependent on?

Answer 14

• Individual
• Allergen
• Mode of introduction

Question 15

Where is asthma localised to?

Answer 15

Respiratory system

Question 16

Where is eczema localised to?

Answer 16

Dermis

Question 17

Give examples of fairly common food allergens.

Answer 17

• Peanuts
• Eggs
• Milk
• Dairy

Question 18

Give examples of less common food containing allergenic proteins.

Answer 18

• Soy
• Wheat
• Fish
• Shellfish
• Fruits
• Vegetables
• Spices

Question 19

What are common symptoms of an allergic reaction.

Answer 19

• Sneezing
• Nasal congestion
• Runny nose
• Swelling and tenderness of the mouth
• Difficulty breathing
• Flushing or rash
• Burning and itching of the skin
• Hives
• Nausea/vomiting
• Abdominal cramps
• Diarrhoea

Question 20

What is the pathophysiology of allergy?

Answer 20

IgE mediated triggering of mast cells and subsequent accumulation of inflammatory cells at sites of antigen deposition

Question 21

What happens on first exposure to allergen?

Answer 21

• Response with T cells and B cell producing IgE

- IgE circulates in the blood and binds to an IgE specific receptor

Question 22

What is the acute response on exposure to allergen?

Answer 22

• Ag+ specific IgE
• Degranulation with release of histamine, cytokines, interleukins, leukotrienes and prostaglandins from their granules causing systemic effects such as vasodilation, mucous secretion, nerve stimulation and smooth muscle contraction

Question 23

When does the late phase response occur on exposure to allergen?

Answer 23

2-4 hours later

Question 24

What is the late phase response to allergen due to?

Answer 24

Migration of other leukocytes such as neutrophils, lymphocytes , eosinophils and macrophages to the initial site

Question 25

What are the host related risk factors for allergen?

Answer 25

- Hereditary - Race - Age

Question 26

What are the environmental related risk factors for allergen?

Answer 26

- Alterations in exposure to infectious diseases during early childhood - Environmental pollution - Allergen levels - Dietary changes

Question 27

How is an allergy diagnosis made?

Answer 27

- Skin test: responses to known allergens- high NPV, up to 15% false positives - RAST: presence an levels of allergen-specific IgE

Question 28

What different modalities of treatment are there for allergies?

Answer 28

- Allergen avoidance - Immunotherapy - Pharmacotherapy

Question 29

What is the traditional treatment for allergies?

Answer 29

Avoidance

Question 30

What is involved in avoiding allergens?

Answer 30

- Avoiding or reducing exposure to the allergen in question | - Cat allergies: easy to avoid cats but difficult to avoid air-borne allergies

Question 31

Why are drugs used the treatment of allergies?

Answer 31

To prevent activation of cells and degranulation processes or to block the action of allergic mediators

Question 32

What drugs can be used in the treatment of allergies?

Answer 32

- Antihistamines - Glucosteroids - Epinephrine - Theophylline - Cromolyn sodium - Antileukotrines

Question 33

What is involved in immunotherapy?

Answer 33

Controlled exposure to known allergens to reduce the severity of allergy

Question 34

What is immunotherapy useful in?

Answer 34

- Allergic rhinitis - Allergic asthma - Allergic conjunctivitis

Question 35

What is immunotherapy not useful in?

Answer 35

- Food allergy - urticarial - Atopic dermatitis

Question 36

How does immunotherapy work?

Answer 36

- Desensitization: vaccinated with progressively larger doses of the allergen - Increasing IgG antibody production blocks excessive IgE production - The person builds up immunity to increasing amounts of the allergen in question

Question 37

Allergic rhinitis

Answer 37

Allergic inflammation of the nasal airways

Question 38

When does allergic rhinitis occur?

Answer 38

When an allergen is inhaled by an individual with a sensitized immune system

Question 39

What are the clinical features of an allergic response?

Answer 39

- Sneezing - Coughing - Wheezing - Runny nose - Weepy eyes - Itchiness

Question 40

What are the classifications of allergic rhinitis?

Answer 40

- Seasonal | - Perrennial