type 1 hypersensitivity; immediate hypersensitivity (allergy)
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Introduction
Mediated by IgE & other immunoglobulins.
Classification
associated conditions include:
- allergic asthma
- allergic rhinitis
- anaphylactoid reactions to drugs
- 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
- T-helper-2 (Th2)-mediated switch of antigen-specific B-cells to production & release of IgE
- IgE-mediated degranulation of mast cells
- influx of eosinophils
- late-phase response
- recurrence of symptoms 6-8 hours after exposure
- recruitment of eosinophils, monocytes & to a lesser extent neutrophils to site of allergen exposure
- 2nd wave of mast-cell degranulation
- biphasic response rare[4]
History
- relationshiop of symptoms to:
- medications
- family history of allergic disorders
- exacerbating factors (asthmatic patients):
- sensitivity to aspirin
- postnasal drainage from sinuses
- nocturnal symptoms
Clinical manifestations
- hypotension
- tachycardia
- shortness of breath
- asthma: wheezing, coughing
- urticaria
- lichenification of skin from atopic dermatitis
Laboratory
Radiology
- interstitial changes on chest X-ray not seen
Management
- antihistamines
- steroids
- epinephrine*
- 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]
More general terms
More specific terms
- 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
Additional terms
- adverse drug reaction (ADR)
- atopic state
- eosinophil
- immunoglobulin-E (IgE)
- mast cell
- T helper 2 (Th2) cell
References
- ↑ Medical Knowledge Self Assessment Program (MKSAP) 11, American College of Physicians, Philadelphia 1998
- ↑ 2.0 2.1 ARUP Consult: Allergic Disease The Physician's Guide to Laboratory Test Selection & Interpretation http://arupconsult.com/Topics/AllergicDisease.html
- ↑ 3.0 3.1 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 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/24508301 <Internet> http://www.jacionline.org/article/S0091-6749%2813%2902964-3/abstract
- ↑ 4.0 4.1 4.2 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: https://www.ncbi.nlm.nih.gov/pubmed/24239340
- ↑ 5.0 5.1 Hesselmar B et al Allergy in Children in Hand Versus Machine Dishwashing. Pediatrics. Feb 23, 2015 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/25713281 <Internet> 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 <PubMed> PMID: https://www.ncbi.nlm.nih.gov/pubmed/25713279 <Internet> http://pediatrics.aappublications.org/content/early/2015/02/17/peds.2014-3911 - ↑ 6.0 6.1 6.2 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: https://www.ncbi.nlm.nih.gov/pubmed/29610864 https://jamanetwork.com/journals/jamapediatrics/fullarticle/2676167
- ↑ 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: https://www.ncbi.nlm.nih.gov/pubmed/30886111 https://pediatrics.aappublications.org/content/early/2019/03/15/peds.2019-0281
Patient information
type 1 or immediate hypersensitivity (allergy) patient information