W13_07 allergy and immunology

Question 1

what’s an allergy?

Answer 1

due to excessive IgE production to certain antigens

Question 2

what mediators are released when a bound IgE binds its antigen?

Answer 2

histamine;
prostaglandins;
leukotrienes

Question 3

what are the most common food alelrgens in children?

Answer 3

cow milk;
chicken egg;
legumes;
tree nuts;
fish;
crustaceans;
mollusk;
cereal grains

Question 4

note: the major food allergens are primarily water-soluble glycoproteins with a molecular weight of 10-65 kDa

Answer 4

ok

Question 5

note: the cost of rhinoconjunctivitis alone in 1996 in the US was 6 billion dollars

Answer 5

ok

Question 6

what’s the allergic salute?

Answer 6

rub nose upwards to wipe out the snot. Leaves a horizontal crease in the nose. Advise against

Question 7

define rhinitis

Answer 7

inflammation of the membranes lining the nose

Question 8

define atopy

Answer 8

allergic reaction in a body part not in contact with the allergen

Question 9

what’s the skin prick test?

Answer 9

placement of a small drop of extract on the volar surface of the forearm or back;
doesn’t determine allergic disease, but tests for presence of IgE antibodies

Question 10

note: NPV of skin prick test is very high (99%), PPV is variable (less than 50% for some foods)

Answer 10

ok

Question 11

which allergy does intracutaneous testing usually test for?

Answer 11

penicillin;
vaccines;
venom;
(note: used after negative SPT, but many false positives)

Question 12

what’s the gold standard for food allergy diagnosis?

Answer 12

double-blind, placebo-controlled food challenge

Question 13

what’s the radioallergosorbent test?

Answer 13

rast test;
kind of like an elisa, using a radio-labelled antigen

Question 14

what’s xolair?

Answer 14

anti-IgE antibody;
omalizumab

Question 15

note: you can decrease humidity to reduce allergies

Answer 15

ok (shortens the life cycle of bugs that produce allergens)

Question 16

what are some pharmacologic therapies to allergy?

Answer 16

oral: antihistamines, decongestants, antileukotrienes;
nasal: antihistamines, corticosteroids

Question 17

what’s the working definition of anaphylaxis?

Answer 17

severe involvement of respiratory function and/or hypotension, plus clinical features like skin involvement and GI symptoms

Question 18

anaphylaxis is a clinical diagnosis. But there is a protein that’s considered a marker. What is it?

Answer 18

serum tryptase

Question 19

when does the biphasic reaction of anaphylaxis occur, if it occurs?

Answer 19

within 4-8 hours in 15-30% of anaphylaxis cases

Question 20

what’s the acute management of anaphylaxis?

Answer 20

ABC;
large bore IV;
epi IM (IV if critically ill);
diphenhydramine;
steroids