anaphylactic reaction


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Related to anaphylactic reaction: anaphylactoid reaction

anaphylactic

 [an″ah-fi-lak´tik]
pertaining to or affected by anaphylaxis.
anaphylactic reaction anaphylaxis.
anaphylactic shock a serious and profound state of shock brought about by hypersensitivity (anaphylaxis) to an allergen such as a drug, foreign protein, or toxin. Sometimes it occurs upon second injection of a patient with a previously injected serum or protein.

an·a·phy·lax·is

(an'ă-fi-lak'sis),
An induced systemic or generalized sensitivity; at times the term anaphylaxis is used for anaphylactic shock. The term is commonly used to denote the clinical reaction seen with system IgE-mediated hypersensitivity reaction. Multivalent antigen crosslinks IgE on the surface of tissues mast cells, causing degranulation with release of preformed mediators (for example, histamine). Generation of newly synthesized mediators occurs rapidly. The physiologic manifestations reflect the biologic effects of these mediators. Cutaneous symptoms include pruritus, erythema, urticaria, and angioedema. Respiratory compromise can come from laryngeal obstruction or bronchospasm. Cardiac effects include arrhythmia, hypotension, and shock. The reaction may be fatal if asphyxiation or cardiovascular collapse occurs.
[G. ana, away from, back from, + phylaxis, protection]

anaphylactic reaction

Etymology: Gk, ana, phylaxis, protection; L, re, agere, to act
an acute allergic response involving IgE-mediated, antigen-stimulated mast cell activation resulting in histamine release. Exposure to the antigen may result in dyspnea, airway obstruction, shock, urticaria, and in some cases, death. Anaphylactic reactions may be caused by bee stings, foods, allergen extract, medications, or exercise. Rapid administration of subcutaneous epINEPHrine is the treatment of choice for severe reactions.

anaphylactic reaction

An antigen-induced, IgE-mediated release—and production—of chemical mediators, the target of which is blood vessels and smooth muscle.
 
Clinical findings
Bronchospasm, dyspnoea, hypotension, oedema, shock and possibly death.
 
Pathogenesis
An anaphylactic reaction is a hypersensitivity type-I reaction which follows re-exposure to an antigen to which the body has previously formed an IgE antibody; within seconds of exposure to the antigen(s) (which may be proteins, polysaccharides and haptens), IgE molecules cross-link on the surface of mast cells and basophils, stimulating vesicle degranulation and release of LBW mediators of anaphylaxis. In the 1º response, preformed molecules are released, including eosinophil chemotactic factor and vasoactive substances (e.g., heparin, histamine, serotonin and various enzymes); in the 2º response, acute-phase reactants are produced and released. Fatal and near-fatal ARs in children are commonly evoked by peanuts, nuts, eggs, milk, fish and others.
 
Management
Epinephrine as soon as possible.

anaphylactic

pertaining to anaphylaxis.

anaphylactic reaction
anaphylactic shock
a serious and generalized state of shock brought about by hypersensitivity (anaphylaxis) to an allergen, such as a drug, foreign protein or toxin.
References in periodicals archive ?
As soon as a patient has an anaphylactic reaction, they should be placed in the supine position with lower extremities elevated; they should not stand up and move as this has been reported to increase the risk of severe anaphylaxis or sudden death.
Can cause anaphylactic reaction to previous rubella vaccine, eggs, or neomycin.
This case report documents a successful L-AmB challenge and possible desensitization in a very severe neutropenic patient with AAA who had aspergillosis as well as zygomycosis and had a prior anaphylactic reaction associated with L-AmB.
Effect of Kumhwang-San on anaphylactic reaction in a murine model.
However, at this point an ethical issue emerges as many states have laws that do not cover the camp staff in using this drug to treat an anaphylactic reaction.
At least 40 people die every year in the United States from severe anaphylactic reactions triggered by the stings of yellow jackets, wasps, bees, hornets, or fire ants.
Every patient who has had an anaphylactic reaction should receive some form of injectable epinephrine for use in an emergency.
ACE inhibitors, aspirin, and alcohol each appear to increase the risk for an anaphylactic reaction in adults with food allergies, Dr.
Reactions to carmine tend to be in the form of hives and swelling although one case of anaphylactic reaction to Campari-Orange has been reported.
I have patients with similar symptoms to Heather and they are so sensitive that even a brush with an allergic substance could easily bring on an anaphylactic reaction and prove to be fatal.
We have all heard of the person who dies because of an overwhelming anaphylactic reaction to a bee sting, yet we do not associate this kind of an event with a latex allergy.
Because an anaphylactic reaction can be fatal, all bee stings should be treated immediately.