title: Mechanisms of Anaphylaxis Beyond IgE.
abstract: Anaphylaxis is an acute, life-threatening, multisystem syndrome resulting from the sudden release of mediators derived from mast cells and basophils. Food allergens are the main triggers of anaphylaxis, accounting for 33%-56% of all cases and up to 81% of cases of anaphylaxis in children. Human anaphylaxis is generally thought to be mediated by IgE, with mast cells and basophils as key players, although alternative mechanisms have been proposed. Neutrophils and macrophages have also been implicated in anaphylactic reactions, as have IgG-dependent, complement, and contact system activation. Not all allergic reactions are anaphylactic, and the presence of the so-called accompanying factors (cofactors or augmenting factors) may explain why some conditions lead to anaphylaxis, while in other cases the allergen elicits a milder reaction or is even tolerated. In the presence of these factors, allergic reactions may be induced at lower doses of allergen or become more severe. Cofactors are reported to be relevant in up to 30% of anaphylactic episodes. Nonsteroidal anti-inflammatory drugs and exercise are the best-documented cofactors, although estrogens, angiotensin-converting enzyme inhibitors, β-blockers, lipid-lowering drugs, and alcohol have also been involved. The mechanisms underlying anaphylaxis are complex and involve several interrelated pathways. Some of these pathways may be key to the development of anaphylaxis, while others may only modulate the severity of the reaction. An understanding of predisposing and augmenting factors could lead to the development of new prophylactic and therapeutic approaches.
authors.affiliation: Unitat d'Al·lergia, Servei de Pneumologia, Hospital Clinic, Universitat de Barcelona, Barcelona, Spain.|Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Red de Investigación de Reacciones Adversas a Alérgenos y Fármacos (RIRAAF), Instituto de Salud Carlos III. (ISCIII), Spain.
authors.forename: R
authors.initials: R
authors.lastname: Muñoz-Cano
authors.affiliation: Unitat d'Al·lergia, Servei de Pneumologia, Hospital Clinic, Universitat de Barcelona, Barcelona, Spain.|Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Centro de Investigaciones Biomedicas en Red de Enfermedades Respiratorias (CIBERES), Spain.
authors.forename: C
authors.initials: C
authors.lastname: Picado
authors.affiliation: Unitat d'Al·lergia, Servei de Pneumologia, Hospital Clinic, Universitat de Barcelona, Barcelona, Spain.|Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Centro de Investigaciones Biomedicas en Red de Enfermedades Respiratorias (CIBERES), Spain.
authors.forename: A
authors.initials: A
authors.lastname: Valero
authors.affiliation: Unitat d'Al·lergia, Servei de Pneumologia, Hospital Clinic, Universitat de Barcelona, Barcelona, Spain.|Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Red de Investigación de Reacciones Adversas a Alérgenos y Fármacos (RIRAAF), Instituto de Salud Carlos III. (ISCIII), Spain.
authors.forename: J
authors.initials: J
authors.lastname: Bartra
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000009:adverse effects; D000485:Allergens / Q000276:immunology / Q000494:pharmacology*; D000707:Anaphylaxis / Q000139:chemically induced / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects; D001491:Basophils / Q000276:immunology / Q000473:pathology; D003165:Complement System Proteins / Q000378:metabolism; D004967:Estrogens / Q000009:adverse effects; D000431:Ethanol / Q000009:adverse effects; D005512:Food Hypersensitivity / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D000960:Hypolipidemic Agents / Q000009:adverse effects; D007073:Immunoglobulin E / Q000378:metabolism; D007074:Immunoglobulin G / Q000378:metabolism; D008264:Macrophages / Q000276:immunology / Q000473:pathology; D008407:Mast Cells / Q000276:immunology / Q000473:pathology; D009504:Neutrophils / Q000276:immunology / Q000473:pathology
chemical_list: D000319:Adrenergic beta-Antagonists; D000485:Allergens; D000806:Angiotensin-Converting Enzyme Inhibitors; D000894:Anti-Inflammatory Agents, Non-Steroidal; D004967:Estrogens; D000960:Hypolipidemic Agents; D007074:Immunoglobulin G; D007073:Immunoglobulin E; D000431:Ethanol; D003165:Complement System Proteins
keywords: Adenosine; Anaphylaxis; Cofactor; Exercise; IgE; IgG; Mast cell; NSAID