Pediatric Asthma and Allergies Lecture Powerpoint Flashcards
Not all allergic reactions are… (2)
…atopic, and not all are IgE mediated (think non-allergic rhinitis)
The allergic response is thought to be due to a combination of factors including (5)
- genetics
- age
- environment
- exposure
- sensitization
Antigen presenting cells
Include cells such as dendritic, langerhan, and macrophages, induce allergic inflammation by presenting allergen to T cell on their MHC class II, priming naive T cells
T helper cells
Type 2 T cells, secrete cytokines that cause IgE mediated responses as well as interleukins, thought to play a large role in asthma and allergies
Eosinohpils
Help defentd against parasites, accumulate where allergic cxns take place as well and release inflammatory proteins
Mast cells
Mediators of the llaergic response, do not circulate but are located around connective tissue and alongside basophils degranulate releasing histamine and cytokines, depending on where they release will see different impacts such as GI inflammation, airway congestion, and blood capillary dilation
Early vs late phase allergic response vs chronic response
Early is due to mast cells degranulating massive amounts of histamine and occurs within minutes, late response occurs after hours post exposure and is associated with infiltration of neutrohpils, eosinophils, basophils, monocytes, and macrophages, chronic is continuing of this and will see tissue remodeling with irreversible damage to target organs
Hygiene hypothesis
Refers to the idea that children who are in less sterile environments have a lower risk of allergic disorders compared to those that are in more sterile environments
Symptoms of allergic dz in children (9)
- careful history and PE
- triggers
- age of presentation (younger more food or environment, older seasonal)
- congestion or sneezing
- wheezing or SOB
- rash
- allergic shiners
- nausea and vomiting
- frontal headache
3 allergic behaviors
- allergic salute (rub nose upward with palm of hand, creates transverse nasal crease)
- allergic click (tongue against roof of mouth to scratch soft palate - I do this)
- rubbing of eyes
Dennie morgan lines
exaggerations of folds under the eyelid present in patients having an allergic reaction
2 things that can help differentiate allergic rhinitis from colds
- fever is infectious
- itchiness is almost always allergic
Diagnostic testing for allergies
- Radioallergosorbent test (document allergen specific IgE but less sensitive than skin test)
- skin allergy testing
- methacholine challenge test (bronchial provocation, non-asthmatics do not constrict)
Environmental control for allergies (6)
- dust mite feces are often source of allergen, do not survive in humidity <50%
- remove pet or at least limit space, takes 6 months to clear allergens from home
- limit pests and insects
- stop tobacco smoking
- wipe down walls and avoid mold (humidity >50%)
- keep windows closed and use AC
Drug of choice for anaphylaxis
epinephrine
