Allergy

Question 1

Define allergy and hypersensitivity

Answer 1

undesirable, damaging and sometimes fatal reaction produced by normal immune system in a PRE-SENSITISED host

Question 2

How many types of hypersensitivity are there?

Answer 2

4

Question 3

Which antibodies are associated which the 4 types of hypersensitivity?

Answer 3

1 - IgE
2 - IgG, IgM
3 - IgG, IgM
4 - mainly cell mediated

Question 4

Which type of hypersensitivity is cytoxic?

Answer 4

2

Question 5

What are the clinical features of type II hypersensitivity?

Answer 5

onset is minutes/hours

cell lysis and necrosis

Question 6

What is the common antigen for type II hypersensitivity?

Answer 6

penicillin

Question 7

Name 2 associated diseases with type II hypersensitivity

Answer 7

Goodpasture’s nephritis,

Erythroblastosis fetalis

Question 8

What is the key feature of antigens reacted to in type III hypersensitivity?

Answer 8

soluble

Question 9

What is the traditional cause of type III hypersensitivity?

Answer 9

serum sickness

Question 10

What disease is associated with type III hypersensitivity?

Answer 10

SLE

Question 11

Which type of hypersensitivity is associated with vasculitis?

Answer 11

Type III

Question 12

What is the immunopathology of type IV hypersensitivity?

Answer 12

antigen specific T-cell mediated cytotoxicity

Question 13

Which type of hypersensitivity has a delayed reaction?

Answer 13

Type IV (48-72 hrs)

Question 14

What are common antigens for type IV hypersensitivity?

Answer 14

cheap metals (like nickel)

Question 15

Name a disease associated with type IV hypersensitivity

Answer 15

contact dermatitis

Question 16

What 2 features lead to changes in T cell sub-sets in the development of allergy?

Answer 16

barrier dysfunction and sensitisation

Question 17

Is the lack of infectious drive a contributory factor in allergic disease?

Answer 17

yes

Question 18

which antibodies are associated with immune responses to parasitic disease?

Answer 18

IgE

Question 19

What do CD4+ T cells produce in immune response to parasitic disease?

Answer 19

IL4, IL5, IL13

Question 20

What is the protective stimulation of hygiene hypothesis?

Answer 20

microbes

Question 21

What is the mechanism of the hygiene hypothesis?

Answer 21

Th1 Th2 deviation

Question 22

Define allergens

Answer 22

antigens that initiate an IgE mediated response

Question 23

What does the first encounter with allergens result in?

Answer 23

innate and IgM reponse

Question 24

What is the late phase response of the IgE mediated allergic response?

Answer 24

eosinophils, central role for Th2 T cell

Question 25

what are the immediate symptoms of asthma?

Answer 25

IgE mediated

Question 26

Why do you get damage to airways in asthma?

Answer 26

due to late phase response

Question 27

Define anaphylaxis

Answer 27

an acute, potentially life threatening, IgE mediated systemic hypersensitivity reaction

Question 28

What are the 2 types of allergic rhinitis?

Answer 28

perennial or seasonal

Question 29

What are allergens for allergic rhinitis?

Answer 29

house dust mites, animal danders, pollens

Question 30

How do you treat allergic rhinitis?

Answer 30

antihistamines and nasal steroids

Question 31

How do you treat atopic dermatitis?

Answer 31

topical steroids and moisturisers

Question 32

What are the disadvantages of skin prick test for diagnosis?

Answer 32

false negatives, false positives, antihistamines, slight risk

Question 33

What are the advantages of speficic IgE for diagnosis?

Answer 33

Safe

Question 34

What are the three main treatments for allergic reactions?

Answer 34

antihistamines, steroids and adrenaline

Question 35

Which phases of reactions are reduced by specific immunotherapy?

Answer 35

intermediate and late phase allergic infammation

Question 36

What are the cutaneous manifestations of a food allergy?

Answer 36

urticaeria, angioedema