Allergy/Immunology Flashcards
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When is allergy testing indicated, and what is the preferred method?
- Suspected food, drug, insect allergy
- Difficult to treat allergic rhinitis or conjunctivitis, asthma, or atopic dermatitis
- More than one atopic disorder
Allergic rhinitis with recurrent otitis media or sinusitis
When is in vitro testing helpful?
- It can help identify things you are sensitive to, high risk of anaphylaxis, suspicion of allergy is high and it may take a while to see an allergist
- You are only allergic if you are sensitized and have an adverse reaction
What does a positive result indicate?
Allergy is present
How is skin testing done and are there risks?
- Can be done via skin prick or intradermal testing
- Can be used for any type of allergic disorder
- A reaction will occur after15 minutes
- Intradermal is more accurate
- Patch testing is done for allergic contact dermatitis; can take several days to develop a reaction
Anaphylaxis
Presenting S/S
Respiratory compromise - dyspnea, wheezing, bronchospasm, stridor
Circulatory compromise - hypotension, end organ dysfunction, collapse
Severe GI - severe crampy ABD pain, repetitive vomiting
OR
Acute onset of hypotension, bronchospasm, laryngeal involvement after exposure to known or highly probable allergen for the patient, even in the absence of typical skin involvement
Anaphylaxis
Risk Factors
Allergy to the following:
PCN (penicillin)
Cephalosporins
Radiocontrast media
Peanut, tree nuts
Cow’s milk
Seafood
Latex
Insect stings
asthma + food allergy is highest risk
Cardiovascular conditions
Delayed or no administration of epinephrine
When to administer Epinephrine? What to do after?
- Trouble breathing, tightness in throat, light headed/pass out
- Give EPI
- Call 911 (after giving it)
- Keep the child supine
If symptoms aren’t stabilizing or improving within 5 minutes, give 2nd dose of EPI
Lift legs up to increase blood flow to vital organs
Food Allergy vs. Food Reaction
Reaction– GI upset caused by ingestion of food, can be caused by GERD, non-celiac gluten sensitivity, intolerance to food or flavoring
Allergy– abnormal immune reaction to a food that causes symptom when exposed
(Sensitization- presence of IgE to a specific allergen + adverse health effect)
Peak prevalence at one year of age
Common Food Allergens
Childhood- milk, eggs, peanuts, tree nuts, wheat, soybeans
Peanut, tree nut, and shellfish allergies persists into adulthood
IgE Mediated onset and symptoms
- Rapid onset within minutes, no more than 2 hours after ingestion
- Urticaria and angioedema are earliest and most common - 30 mins
- Prominent GI symptoms with Upper GI symptoms (N/V ABD pain)
- Oropharyngeal symptoms and/or respiratory symptoms
- Children have urticaria and vomiting
- Can cause anaphylaxis
Important element of Hx and PE
- The food? Which food was suspected? How was it ingested?
- How long have symptoms started? How was it treated?
- Did symptoms start before or after physical exertion?
- Have NSAIDS been taken or alcohol?
- Has this happened before? Do they have atopic conditions? First degree relatives with food allergies?
IgE - can happen with one bite and within minutes
When to refer, prescription, epi, labs to order?
All food allergies need to see an allergist
Labs- order allergen specific immunoassay if high suspicion for IgE
EPI- WHEN to give
1. Previous confirmed or suspected reaction
2. High risk food like peanuts or tree nuts
3. High risk patient- asthma, severe eczema, taking a beta blocker
4. Reaction to trace amount of food
5. Monitor growth and nutrition
General Information on Food Avoidance
- Read labels
- Ask about ingredients when eating out
- Saliva: wait several hours before eating a different food before kissing or sharing utensils
- Safe food preparation and cleaning
- Have a plan for school/daycare
- Ingestion can cause cutaneous symptoms
- Inhaled of aerosolized food during cooking or preparation process may cause nasal or respiratory symptoms
Oral Allergy Syndrome
S/S and Cause
- IgE mediated reaction to pollen-related food (fresh uncooked fruits, vegetables, legumes, nuts or seeds)
- Most common in patients with seasonal nasal, ocular, respiratory symptoms triggered by pollen
- Symptoms are immediate and limited to oropharynx and typically resolved withing minutes of swallowing the food (itching, irritation, tingling, mild erythema and mild swelling of lips, tongue, palate, throat)
Approach to introducing HIGH allergy foods
(cow’s milk, egg, peanuts, tree nuts, soy, wheat, sesame, fish, shellfish)
- Start with peanut and egg containing food
- If above are tolerated, continue to add others - Cow’s milk can be in the form of yogurt, cheese, or other diary products
- INTRODUCE TO INFANT WHEN:
-Age >4 months (typical age is 6 months)
-Developmentally ready
-Already tired and tolerated a few low allergenic foods - Start with just a taste of the food; if no reaction, gradually increase the amount of food over time
