Global Perspectives on Obstetric Anesthesia: Challenges and Priorities for Advancing Maternal Health

Allergic anaphylaxis is most commonly caused by the interaction of an allergen with specific immunoglobulin E (IgE) antibodies. These antibodies, in sensitized individuals, bind to high-affinity Fc3RI receptors located in the plasma membrane of tissue mast cells and blood basophils, and to low-affinity Fc3RII receptors on lymphocytes, eosinophils, and platelets. This interaction stimulates the cells to release preformed and newly synthesized inflammatory mediators, such as histamine, tryptase, phospholipid-derived mediators (i.e., prostaglandin D2, leukotrienes, thromboxane A2, and platelet-activating factor) as well as several chemokines and cytokines, which account for the clinical features. /n Anaphylaxis can be differentiated from an anaphylactoid reaction in that, in anaphylaxis, the mast cell degranulation and histamine release is IgE mediated. In an anaphylactoid reaction, mast cell degranulation and histamine release is not immune-mediated.