Allergy and Immunology Flashcards
Role for IV epi in anaphylaxis
- after repeated doses of IM epi
- persistent hypotension despite fluid resuscitation wtih 20mL/kg of NS
concentration 0.1mg/mL (1:10,000)
Biphasic reaction
- most are in first 4-6 hrs (range 1-72 hrs)
- higher risk if delayed epi, more than 1 epi doses, more severe sx (b-agonist given, wide pulse pressure)
25kg epipen
0.3mg IM
Skin prick testing pros:
- results within 15 minutes
- more sensitive
- high negative predictive value
- cost effective
Skin prick testing cons:
- false positives
- affected by use of antihistamines and corticosteroids
- low risk of having a systemic reaction
- cannot perform if skin disease at testing site (e.g. eczema)
High risk for food allergy (CPS)
- personal history of atopy
- first degree relative with an allergic condition
Food protein induced proctitis onset
2-8 weeks of age
by age 9 months, 95% tolerate
Food protein induced enterocolitis syndrome onset and features
1-4 weeks after intro of the food
- vomiting 1-3hrs after ingestion
- hypotension in 15%
(generally resolve by 3 yrs)
Test to look for systemic mastocytosis
serum tryptase
Cross-reactivity between penicillin and cephalosporins
2%
Erythema multiforme
- target lesions
- +/- mucosal membrane
- cna be infections OR medications
- tx with topical corticosteroids, antihistamines
SJS/TEN onset and features
1-3 weeks of drug exposure
- fever, sore throat
- mucus membranes
- blistering lesions with skin detachment
DRESS onset and features
1-8 weeks of drug exposure
- rash, eosinophilia, hepatic dysfunction, fever, facial angioedema, lymphadenopahty
Serum sickness onset and features
1-3 weeks of drug exposure
- rash, arthralgia, arthritis, renal disease, fever
- low complement
- e.g. ATG, monoclonal antibodies
Serum sickness -like
1-3 weeks of drug exposure
- rash, fever, arthralgia, arthritis
- NO renal disease
- normal complement
- e.g. cefaclor, penicillin
Treatment for SJS/TEN
- discontinue med
- supportive therapy
- steroids + IVIG = controversial
Treatment for DRESS
- discontinue med
- steroids if severe
Treatment for serum sickness
- discontinue meds
- NSAIDS, analgesics
- steroids, PLEX if severe
Treatment for serum-sickness-like
- discontinue med
- NSAIDS, analgesics
- steroids if severe
Hereditary angioedema
- genetics
- test
- triggers
- autosomal dominant
- C1 esterase inhibitor (will be low)
- triggers by trauma, infection, estrogen
Treatment allergic rhinitis
- allergen avoidance
- 2nd gen oral antihistamines (cetirizine, loratadine)
- intranasal steroids
- leukotriene receptor antagonist
- immunotherapy
Humoral deficiencies (B-cell)
- X linked agammaglobulinemia
- common variable immunodeficiency
Combined immunodeficiencies (T and B cell)
- SCID
- Wiskott-Aldrich
- ataxia - telangiectasia
- DiGeorge
Phagocyte defects
- CGD
- leukocyte adhesion deficiency
