Allergy

Question 1

describe the etiology of allergic rhinitis

Answer 1

Type 1 hypersensitivity
1. Sensitization phase: Memory T cells activated, B cells produce allergen specific IgE antibodies
2. Acute phase rxn: minutes of next exposure, memory T cells active, histamine release, acute sxs
3. Late phase rxn: hrs to days later, infiltration of inflammatory cells, chronic sxs

Seasonal/intermittent (pollens) vs Perennial/ persistent (dust mites, mold, dander) type

RF: fam hx, atopic dz, smoke exposure, early abx

Question 2

Describe the clinical presentation of allergic rhinitis

Answer 2

Sneezing, rhinorrhea, congestion, pruritus, +/= sore throat, fatigue, irritability, QOL: sleep, concentration, anx/dep

Signs: allergic shiners, allergic salute, nasal crease, dennie-morgan lines

Question 3

Describe the PE of allergic rhinitis

Answer 3

pale edematous mucosa or erythematous, profuse clear nasal discharge, +/- nasal polyps, conjunctival erythema, tearing, edema of periorbital area, +/- cobblestoning, +/- wheezing

Question 4

Describe the diagnostic testing for allergic rhinitis

Answer 4

IgE skin prick testing (procedure of choice), positive test produces wheal/flare graded 0-4

IgE mediated intradermal testing as second round to negative allergens

Serum IgE levels for specific allergens

CBC w/ diff may show eosinophilia

RAST panel (specific, $$$)

Nasal smear: looks at eosinophils, not specific, good for ruling out infection

Question 5

Describe the treatment for allergic rhinitis

Answer 5

Avoid triggers, Refer to ENT when not improving, immunotherapy, severe sxs, structural issues

Antihistamines:
1st gen: diphenhydramine - mild-mod sxs, 3-12hrs long
2nd gen: cetirizine, fexofenadine, loratadine, levocetirizine: first line, less sedating, 12-24hrs

Antihistamine Nasal spray: Azelastine adjunct prn for congestion

Antihistamine Eye drops: Olopatadine, Ketotifen consistently or prn

Nasal Corticosteroids: Fluticasone, Mometasone - first line option, start 3-4 weeks before season, alone or adjunct with antihistamines

Decongestants:
Sudafed for congestion refractory to antihistamines, causes vasoconstriction, Afrin can cause rebound congestion

Others:
Intranasal cromolyn prevents degranulation of mast cells

Question 6

Describe priming in the context of allergic rhinitis

Answer 6

sxs occur more frequently & severely w/ exposure to lower allergen concentrations (sensitivity increases over time)

Question 7

Describe immunotherapy for allergic rhinitis

Answer 7

allergies with poor control after 1yr trial of meds & environmental control, allergen extract administered subQ, intralymphatic, sublingual, or transQ patch for months/years, $$$, based on their skin test results
- huge sxs reduction

Question 8

Describe the etiology and types of non-allergic rhinitis

Answer 8

Allergy sxs w/o IgE rxn

Infectious, occupational, etc

Vasomotor
- mimics persistent allergic rhinitis, triggered by weather, smoke, pollution

Rhinitis Medicamentosa
- worsening sxs d/t overuse of nasal decongestants (Afrin)

Question 9

Describe the treatment for vasomotor rhinitis and rhinitis medicamentosa

Answer 9

Vasomotor
- avoid triggers, saline nasal spray, Ach nasal spray, +/- antihistamines, nasal steroids

Rhinitis Medicamentosa
- stop the med, resolves in a few weeks

Question 10

Describe the etiology and risk factors for nasal polyps

Answer 10

Benign, mobile, pedunculated, soft, smooth, gray mucosal protrusion from the ethmoid sinus

RF: rhinitis, asthma, drug use, CF

Question 11

Describe the clinical presentation of nasal polyps

Answer 11

Nasal drainage, congestion, facial pressure/pain, recurrent sinus infections, decreased sense of smell, think neoplasm if discharge is unilateral and bloody

Question 12

Describe the treatment for nasal polyps

Answer 12

Observation, nasal corticosteroids first line, oral/injectable steroids, biologics, refer to ENT for surgical removal

Often recur

Question 13

Describe Samster’s Triad

Answer 13

Samster’s Triad: nasal polyps, asthma, ASA sensitivity

Question 14

Describe the etiology of food allergy

Answer 14

Acute IgE immune response to food proteins

Often characterized by anaphylaxis, can worsen with repeat exposures

Common: dairy, wheat, egg, soy, peanut, sesame, tree nut (fish/seafood in adults)

Question 15

Describe the clinical presentation of anaphylaxis in food allergy

Answer 15

Anaphylaxis: full body hives, tongue & throat swelling, difficulty breathing, vomiting

Question 16

Describe the diagnostic testing involved in food allergy

Answer 16

History + IgE skin prick testing, component lab panel testing

Question 17

Describe the treatment for food allergy

Answer 17

Avoidance

benadryl/epinephrine

Oral immunotherapy: 8-14 mos, micrograms in soln of food products (peanuts, tree nuts, milk, egg)

Question 18

Describe oral allergy syndrome

Answer 18

contact rxn d/t cross reactivity of proteins in foods with pollens
- itchy mouth when eating, increased allergic rhinitis sxs
- avoid, antihistamines, cooking foods, allergy shots