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 ?
Two-chair work may be used for distinct reasons that benefit food-allergic adult clients after an anaphylactic reaction.
It may be difficult to prove whether he had a life-threatening anaphylactic reaction in response to indigo carmine.
Indications for the prescription of self-injectable adrenaline devices in the [14] community Absolute indications Previous anaphylactic reaction to a food, insect sting, latex or unavoidable aeroallergen Co-existent unstable or moderate-to-severe persistent asthma and food allergy Idiopathic anaphylaxis Food-dependent exercise-induced anaphylaxis Relative indications Mild-to-moderate peanut/and or tree nut allergy in patients [greater than or equal to] 5 years of age Food allergy in a teenager or young adult Far from a medical facility Reactions to small amounts of food, such as air-borne food allergens or contact via skin only
The most common agent involved in intraoperative anaphylactic reactions is muscle relaxant (61-70%); natural rubber latex (NRL) is the second most implicated agent and the incidence of latex-related anaphylactic reactions is increasing despite increasing awareness and preventive measures taken.
Anaphylactic reactions are more rare than expected, but may be fatal.
Can cause anaphylactic reaction to previous rubella vaccine, eggs, or neomycin.
A pathologist confirmed she had died of a 'massive' anaphylactic reaction.
However, on two occasions, he developed an anaphylactic reaction (urticaria, angioedema, wheezing, and dyspnea) when he engaged in strenuous exercise after drinking milk.
In general, mast cell-mediated anaphylactic reaction is elicited by various stimulators including compound 48/80, concanavalin A and anti-[IgE.
Under no circumstances should the child having the anaphylactic reaction be transported by school personnel to an emergency facility unless no emergency transport services are available in the community.
Epinephrine is a form of adrenaline and is an effective treatment for an anaphylactic reaction.