Allergy, Etc. Flashcards
Type I Hypersensitivity
IgE mediated
Ex: Anaphylaxis, angioedema, food allergy, insect bite
Type II Hypersensitivity
IgG or IgM mediated
Complement activation involved
Ex: Transfusion reaction, hemolytic disease of newborn
Type III Hypersensitivity
IgG or IgM mediated
Antigen-antibody complexes
PSGN, RA, SLE
Type IV Hypersensitivity
Th1 cell mediated
DELAYED
Contact dermatitis (poison ivy), MS
“Contraindications” to allergy testing
Must stop antihistamines, beta agonists, TCAs prior to testing
No glycerin sensitivity (serves as control), no skin conditions (i.e. dermatographia)
Intradermal Dilutional Testing - what is the endpoint?
Endpoint is when you get > 2 mm from “control” - helps determine safe starting point for immunotherapy.
If you don’t get ANY 2 mm or more difference, it’s a negative test!
Only two branches of ICA in the nose
Anterior and posterior ethmoids (from ophthalmic branch of ICA) - you do NOT embolize these!
What is the dose of epi in an epi pen?
0.3 mg
Most prevalent allergens in:
Spring
Summer
Fall
Year Round
Spring: Tree pollen
Summer: Grasses
Fall: Ragweed
Mold: All year round
Kiesselbach’s Plexus
Septal b. of sup. labial (from facial –> ECA)
Anterior ethmoid (from ICA)
Sphenopalatine (from IMAX –> ECA)
Greater palatine (from IMAX –> ECA)
What fungus is associated with the Ohio and Mississippi river valley?
Histoplasmosis
Which chemokines are responsible for IgE recruitment and what type of inflammation is this?
IL-4, 5 and 13
Type TWO inflammation (CRSwNP)
Mechanism of Atrovent and uses?
Anticholinergic agent, aka ipratropium bromide, used for vasomotor rhinitis but also can be used for allergic rhinitis. Less effective for coughing, sneezing, etc.
One intranasal corticosteroid that is NOT safe for pregnancy?
Triamcinolone.
Mechanism of Montelukast + uses?
Leukotriene receptor antagonist, used for seasonal allergies.
Black box warning for psych side effects
OK to continue with allergy testing.
What has cross reactivity with latex?
Avocado, chestnut, banana, kiwi and papaya can exhibit allergy cross reactivity with latex.
Which interleukins are involved in TH1 vs TH2 response?
TH1: IL10, IL12, IFN gamma
TH2: IL4, 5 and 13 (dont forget IL33 is involved in activation of these)
CVID Features?
-Decreased IgG, IgA, some have low IgM
-Think young adults with respiratory disease, granulomas, malignancy
-TX: IVIG
Brutton’s agammaglobulinemia features?
-Tyrosine kinase issue affects B cells - can’t produce antibodies
-~6 months of age presentation, usuall in young boys
-Lots of sinopulmonary infections
-X linked!
What do TH1 and TH2 cells secrete?
TH1: IFN-gamma (–> macrophage activation, Il-2 expression)
TH2: IL-4, IL-5, IL-13
Type V hypersensitivity features and examples?
Ab resembles a ligand
Ex: Graves, Hashimotos, Myesthenia Gravis
Pathway for sublingual or subcutaneous immunotherapy and timeline? Contraindications? How to monitor?
Upregulated T reg cells produce IL-10, INHIBIT Th-2 (and switches to TH1 pathway).
3-5 years for TX
Serum total IgE/total IgE for monitoring
Contraindications: Pregnancy, autoimmune, anaphylaxis
How does RAST work and who is it good for?
In VITRO blood testing
Blood test looking at how much of patient’s IgE in serum binds to Ag (basically…). Compares IgE to specific allergen/Total IgE
-Must wait 4-6 weeks post allergic reaction
-Good for people who can’t stop certain medications, have high risk of anaphylaxis, dermatographia, etc.
-More SPECIFIC, LESS sensitive than skin testing
-Interpretation:
0-2 insignificant
3-6 significant
5-6 severed
Intradermal Dilution Testing
-Helpful for determining immunotherapy dosages
-Endpoint = first wheal > 2 mm from control (confirms where to start). You do one additional injected which should be > 2 mm from endpoint, thus CONFIRMING prior endpoint.
-Used as primary testing for penicillin, insect venoms (do 1-2 months after sting)
Three key findings in central compartment atopic disease?
-Nasal cavity edema/polyps (not so much in the sinuses)
-Hx of Asthma
-Elevated total + specific IgE
*Likely requires allergy management as a core treatment component!
When do you STOP the following for allergy testing?
Topical Steroid
TCA
Oral Antihistamine
Topical Antihistamine
Topical steroid: 3 weeks prior
TCA (the tryptilines): 2 weeks prior
Oral Antihistamine: 5-7 days prior
Topical Antihistamine: 3 days prior
What drugs are OK to continue with allergy testing?
Oral steroids, Leukotriene inhibitors, asthma inhalers, topical nasal steroids
Treatment for anaphylaxis?
Epinephrine, steroids, antihistamines, albuterol inhaler, monitor closely for biphasic reaction!
Tryptase will stay elevated up to 6 hrs (released from mast cells)
Components of:
Innate immunity?
Adaptive immunity?
Innate: Skin, TLR, phagocytes, natural killer cells, compliment, neutrophils, macrophages
Adaptive: B + T Cells
Draw an antibody and explain which part is responsible for antigen binding?
Two parts:
1. Fab - Heavy and ligh chain, binds antigen. N terminal
2. Fc - Heavy chain ONLY, C terminal
IgG = just one
IgM = Pentamer
IgA= Dimer
What cells does IgE bind to to release histamine?
Basophils + mast cells
What does immunotherapy alter (cytokines, etc)?
INCREASES IgG4
INCREASES IL-10
Shifts from TH2 TO TH1
Which Ig deficiency is most common in PEDS vs ADULTS?
PEDS: IgG2
Adults: IgG3
What is the only food allergy approved for SLIT?
What allergies are ok for SCIT?
Peanut allergy. Food allergies are NOT approved for SCIT.
SCIT: Allergic asthma, perennial allergic rhinitis, seasonal allergies unresponsive to other meds, hymeroptra venom
Wiskott Aldrich Syndrome Features?
WATER
X linked
Thrombocytopenia
Eczema
Recurent infection
LOW IgM, NORMAL IgG, ELEVATED IgE + IgA
WASP gene
LEAST and MOST drowsy second generation antihistamine?
Fexofenidine (Allegra) - LEAST
Certirizine (Zyrtec) - MOST
What allergy is least likely to resolve with age?
Tree nuts
What is the MOST common primary immune deficiency and SX?
IgA!
Can be A-sx or have sinopulmonary Infections
At risk of anaphylaxis with blood transfusion that contains IgA
