Allergic disorders in children

Question 1

What three conditions are defined as atopic diseases?

Answer 1

Allergy.
Atopic dermatitis.
Asthma.

Question 2

What is the biodiversity hypothesis?

Answer 2

Reduced biodiversity and alterations in the composition of the gut and skin microbiota are associated with various inflammatory conditions:
– Asthma, Allergy, Eczema, Inflammatory bowel disease, Type I diabetes, Obesity, etc.

Question 3

What is the MeDALL hypothesis?

Answer 3

MeDALL = Mechanisms of the development of allergies.
Persistence or re-occurrence of fetal type 2 signalling genes plays an important role.
– Environmental factors (biodiversity hypothesis)
– Leads to epigenetic changes and a TH1-TH2 shift
– Leads to IgE production against allergens

Question 4

What is the difference between an allergy and an intolerance?

Answer 4

Allergy: Specific IgE-mediated immunologic reaction to an allergen. (E.g. cows milk protein allergy.)

Intolerance: Not mediated via the specific immune system. (E.g. lactose intolerance.)

Question 5

What is “the atopic march”?

Answer 5

Few weeks after birth: Atopic dermatitis.
6-12 months: Food allergy and viral induced asthma.
School age: Exercise induced asthma. Allergic asthma Allergic rhinoconjunctivitis.

Question 6

What are the most common types of allergens for conjuctivitis and rhinitis?

Answer 6

Animal and pollen allergens.

Question 7

What is allergic urticaria?

Answer 7

Itchy, maculopapulous exanthema with shifting sites. May come after all types of allergic exposure.

Question 8

What is most commonly an allergic reaction: Acute or chronic urticaria?

Answer 8

Acute urticaria is most commonly allergic.

Question 9

True or false: In most cases of atopic eczema there is an allergic trigger.

Answer 9

False. In the majority of cases there is no allergic trigger. (Most common triggers are although food, like milk, soy, wheat, nuts, fish, etc.)

Question 10

What are gastrointestinal symptoms of allergy?

Answer 10

Itching/swelling of lips, mouth, throat.
Difficult to swallow, tightness of throat.
Abdominal pain.
Vomiting.
Diarrhea.

Question 11

What are symptoms/signs of allergic asthma?

Answer 11

Dyspne, tachypne, coughing, and expiratory stridor.

Question 12

What are causes of allergic asthma?

Answer 12

Airborne allergens.

Systemic reactions from foods or insect stings.

Question 13

What are the criteria for anaphylaxis?

Answer 13

Anaphylaxis is highly likely when any of following 3 criteria appear after exposure to an allergen:
1) Sudden involvement of the skin/mucosa
AND (at least one): Sudden respiratory symptoms. Sudden reduced BP.

2) Two or more of the following: Sudden skin/mucosal symptoms. Sudden respiratory symptoms. Sudden reduced BP. Sudden GI-tract symptoms.
3) Reduced Blood Pressure.

Question 14

What are the two main components in the work up for diagnosing allergy?

Answer 14

Patient history.

Laboratory tests.

Question 15

True or false: Serum specific IgE tests have high sensitivity, but low specificity. This means it is likely to have positive results even if there is no allergy.

Answer 15

True.

Question 16

What are disadvantages of skin prick tests?

Answer 16

It is unpleasant. (Avoid multiple testing in children.)
It is influenced by medication (dislike serum specific IgE).
It takes skills to perform and interpret.
It has low specificity for allergies.

Question 17

True or false: One if the main problems with allergy testing is that there is many false negative results as well as some false positive results.

Answer 17

False. There are many false positive results as well as some false negatives.

Question 18

What is the main difference between sensitization and allergy?

Answer 18

Allergy = Sensitization + Allergic symptoms. (Lab testing for allergies only prove sensitization. A positive result does therefor not equal allergy.)

Question 19

What is the gold standard for testing of food allergies? What are disadvantages of this test?

Answer 19

Double Blinded Placebo Controlled Oral Food Challenge.

Disadvantages: Time consuming. May induce severe allergic reactions. (Be ready to treat anaphylaxis!)

Question 20

What is an allergen source, allergen extract and allergen component?

Answer 20

Allergen source - source of the allergens, e.g. a peanut.
Allergen extract - a mixture of different allergens from a single allergen source.
Allergen component - a specific allergen/protein in an allergen extract.

Question 21

What are the principles of allergy treatment?

Answer 21

Avoid allergen.
Symptomatic treatment - reduce allergy symptoms.
Curative treatment (if possible).

Question 22

What are forms of symptomatic treatment against allergy?

Answer 22

Systemic treatments, such as antihistamines, corticosteroid injections or leukotriene receptor antagonists (LTRA).
Local treatments, such as eye droplets, nose spray, and inhalations (SABA, LABA, ICS).
Adrenaline (intramuscular) to treat anaphylaxis.
Specific immunotherapy.

Question 23

How is anaphylaxis treated?

Answer 23

ADRENALINE I.m. injection.
Intravenous fluid.
Corticosteroids i.v. or p.o.
Antihistamines i.v. or p.o
Short acting β2 agonist inhalation (SABA).

Question 24

What is specific immune therapy? What types of allergies treat?

Answer 24

Also known as desensitization or hypo-sensitization, is a medical treatment for allergies. It involves exposing people to larger and larger amounts of allergen in an attempt to change the immune system’s response.
It is mainly used to treat allergies for pollen and insect bites.