Hypersensitivity

Question 1

Give a definition for hypersensitivity

Answer 1

An immune response that causes collateral damage to self

Question 2

Which cells mediate type I and type IV hypersensitivity?

Answer 2

Type I - IgE

Type IV - T cells

Question 3

How quickly does type I hypersensitivity occur?

Answer 3

Within minutes - up to 2 hours

Question 4

Give some routes of exposure for type I hypersensitivity

Answer 4

Skin contact
Inhalation
Ingestion
Injection

Question 5

Give some clinical presentations of type I hypersensitivity

Answer 5

Urticaria
Angioedema
Wheeze
Anapylaxis

Question 6

What is the most important investigation in determining type I hypersensitivity?

Answer 6

History!!

Question 7

Give some investigations that can be done for type I hypersensitivity after history

Answer 7

Specific IgE
Skin prick
Challenge test
Serum mast cell tryptase level

Question 8

How is type I hypersensitivity managed?

Answer 8

Avoidance
Anti-histamines
Corticosteroids
Epipen

Question 9

How long does type IV hypersensitivity take to present after exposure?

Answer 9

24-48 hours

Question 10

What is the main skin condition involved in type IV hypersensitivity?

Answer 10

Allergic contact dermatitis

Question 11

Give some examples of what may cause allergic contact dermatitis

Answer 11

Nickel
Fragrance
Garlic

Question 12

What test is used for patients with suspected allergic contact dermatitis?

Answer 12

Patch testing

Question 13

How is type IV hypersensitivity managed?

Answer 13

Avoidance
Topical steroids
UV phototherapy
Immunosuppressants