Anaphylaxis
- DOI:
- 10.1093/med/9780199204854.003.1702_update_001
The term anaphylaxis describes both IgE immune-mediated reactions and nonallergic, nonimmunologically triggered events. Comorbidities such as asthma or infection, exercise, alcohol, or stress and concurrent medications such as β-blockers and aspirin increase the risk known as ‘summation anaphylaxis’.
Aetiology and pathogenesis—activated mast cells and basophils release preformed, granule-associated mediators and newly formed lipid mediators, and generate cytokines and chemokines. These cause vasodilatation, increased capillary permeability, and smooth muscle contraction, as well as attract new cells to the area. Positive feedback mechanisms amplify the reaction in a ‘mast cell—leucocyte cytokine cascade’, although conversely reactions can be self-limiting. Parenteral penicillins, hymenopteran stings, and food are the most common causes of IgE immune-mediated fatalities, with radiocontrast media, aspirin, and other nonsteroidal anti-inflammatory drugs most commonly responsible for nonallergic fatalities....
Access to the complete content on Oxford Medicine Online requires a subscription or purchase. Public users are able to search the site and view the abstracts for each book and chapter without a subscription.
Please subscribe or login to access full text content.
If you have purchased a print title that contains an access token, please see the token for information about how to register your code.
For questions on access or troubleshooting, please check our FAQs, and if you can't find the answer there, please contact us.
