Summary
Definition
History and exam
Key diagnostic factors
- acute onset
- urticaria
- angioedema
- flushing
- dyspnea
- wheezing
- rhinitis
Other diagnostic factors
- allergen ingestion
- insect stings or bites
- pruritus
- inspiratory stridor and hoarse voice
- bilateral conjunctivitis
- nausea and vomiting
- abdominal cramping or pain
- agitation/anxiety
- confusion/disorientation
- tachycardia
- dizziness
- syncope
- sense of impending doom (angor animi)
- recent exercise
- hot or cold exposure
- hypotension
- bradycardia
- cardiac arrest
- diarrhea
- visual disturbances
- tremor
- seizures
Risk factors
- adult age: food-, insect venom-, and medication-related
- <30 years old: food-associated, exercise-induced
- female sex
- atopy/asthma
- history of anaphylaxis
- exposure to a common sensitizer (e.g., latex)
Diagnostic investigations
1st investigations to order
- serum tryptase level
Investigations to consider
- in vitro IgE testing
- skin test
- challenge test
Emerging tests
- basophil activation test
Treatment algorithm
all patients: acute onset
patients with identified allergen
Contributors
Authors
Doerthe Adriana Andreae, MD
Assistant Professor
Pediatric Allergy and Immunology
Penn State Health Milton S. Hershey Medical Center
Hershey
PA
Disclosures
DAA is author of an UpToDate article on food allergy, for which she receives royalties. DAA is an author of a number of references cited in this topic.
Michael Henning Andreae, MD
Associate Professor
Department of Anesthesiology
Penn State Health Milton S. Hershey Medical Center
Hershey
PA
Disclosures
MHA is an author of a reference cited in this topic.
Acknowledgements
Dr Doerthe Adriana Andreae and Dr Michael Henning Andreae would like to gratefully acknowledge Dr Andrea Vereda, a previous contributor to this topic.
Disclosures
AV declares that she is currently employed by Aimmune Therapeutics. AV wrote the main content of this topic before taking up this appointment.
Peer reviewers
Frank J. Domino, MD
Associate Professor
Family Medicine and Community Health
University of Massachusetts Medical School
Worcester
MA
Disclosures
FJD declares that he has no competing interests.
Wayne Shreffler, MD, PhD
Assistant Professor of Pediatrics
Mount Sinai School of Medicine
New York
NY
Disclosures
WS declares that he has no competing interests.
Lawrence Youlten, FRCP (Edin), PhD
Visiting Consultant in Allergy
Addenbrooke’s Hospital NHS Trust
Cambridge
UK
Disclosures
LY declares that he has no competing interests.
Grant Hayman, MBChB, MRCP, DTM and H, MSc, FRCPath
Consultant Immunologist
Department of Immunology
Epsom & St Helier University Hospitals NHS Trust
Carshalton
Surrey
UK
Disclosures
GH declares that he has no competing interests.
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