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type 1 hypersensitivity; immediate hypersensitivity (allergy)

Mediated by IgE & other immunoglobulins. Classification: associated conditions include: 1) allergic asthma 2) allergic rhinitis 3) anaphylactoid reactions to drugs 4) many urticarial reactions Etiology: - use of antiulcer agents associated with increased risk of childhood food allergy (RR=2.2-2.6) [6] - antibiotics early in infancy is associated with increased risk of childhood asthma (RR=2.1) [6] Epidemiology: - children at lower risk of allergic disease if family washes dishes by hand rather than in dishwasher [5] (RR=0.57) Pathology: 1) T-helper-2 (Th2)-mediated switch of antigen-specific B-cells to production & release of IgE 2) IgE-mediated degranulation of mast cells 3) influx of eosinophils 4) late-phase response a) recurrence of symptoms 6-8 hours after exposure b) recruitment of eosinophils, monocytes & to a lesser extent neutrophils to site of allergen exposure c) 2nd wave of mast-cell degranulation d) biphasic response rare [4] History: 1) relationshiop of symptoms to: a) changes in weather b) work 1] chemicals 2] potential irritants 3] stress c) home 1] pets 2] length of time at current residence d) vacation 2) medications 3) family history of allergic disorders 4) exacerbating factors (asthmatic patients): a) respiratory tract infections b) gastroesophageal reflux (GERD) c) allergen exposure 5) sensitivity to aspirin 6) postnasal drainage from sinuses 7) nocturnal symptoms Clinical manifestations: 1) hypotension 2) tachycardia 3) shortness of breath 4) asthma: wheezing, coughing - no pulmonary crackles 5) urticaria 6) lichenification of skin from atopic dermatitis Laboratory: - see ARUP consult [2] Radiology: - interstitial changes on chest X-ray not seen Management: 1) antihistamines 2) steroids 3) epinephrine* 4) biphasic (late) response is rare - prolonged monitoring after resolution of symptoms is not routinely indicated [4] * patients with history of anaphylaxis to food should carry epinephrine kit Prevention: - early introduction of complementary foods in the 1st year of life reduces risk of allergic disease [3]

Related

adverse drug reaction (ADR) atopic state eosinophil immunoglobulin-E (IgE) mast cell T helper 2 (Th2) cell

Specific

allergic bronchopulmonary aspergillosis; allergic bronchopulmonary mycosis (ABPA) allergic conjunctivitis; Angelucci's syndrome allergic rhinitis (hay fever, ragwood allergy) anaphylaxis antibiotic allergy asthma food allergy latex allergy metal allergy tick-related allergy

General

hypersensitivity

References

  1. Medical Knowledge Self Assessment Program (MKSAP) 11, American College of Physicians, Philadelphia 1998
  2. ARUP Consult: Allergic Disease The Physician's Guide to Laboratory Test Selection & Interpretation http://arupconsult.com/Topics/AllergicDisease.html
  3. Roduit C et al. Increased food diversity in the first year of life is inversely associated with allergic diseases. J Allergy Clin Immunol 2014 Apr; 133:1056 PMID: 24508301 http://www.jacionline.org/article/S0091-6749%2813%2902964-3/abstract
  4. Grunau BE et al. Incidence of clinically important biphasic reactions in emergency department patients with allergic reactions or anaphylaxis. Ann Emerg Med 2014 Jun; 63:736 PMID: 24239340
  5. Hesselmar B et al Allergy in Children in Hand Versus Machine Dishwashing. Pediatrics. Feb 23, 2015 PMID: 25713281 http://pediatrics.aappublications.org/content/early/2015/02/17/peds.2014-2968 - Cheng LE, Cabana MD Dishing It Out to Allergies Pediatrics. Feb 23, 2015 PMID: 25713279 http://pediatrics.aappublications.org/content/early/2015/02/17/peds.2014-3911
  6. Mitre E, Susi A, Kropp LE, et al Association Between Use of Acid-Suppressive Medications and Antibiotics During Infancy and Allergic Diseases in Early Childhood. JAMA Pediatr. Published online April 2, 2018 PMID: 29610864 https://jamanetwork.com/journals/jamapediatrics/fullarticle/2676167
  7. Greer FR, Sicherer SH, Burks AW. COMMITTEE ON NUTRITION, SECTION ON ALLERGY AND IMMUNOLOGY. The Effects of Early Nutritional Interventions on the Development of Atopic Disease in Infants and Children: The Role of Maternal Dietary Restriction, Breastfeeding, Hydrolyzed Formulas, and Timing of Introduction of Allergenic Complementary Foods. Pediatrics. March 18, 2019. PMID: 30886111 https://pediatrics.aappublications.org/content/early/2019/03/15/peds.2019-0281