immunology allergic disorders
Anaphylaxis
Introduction
Anaphylaxis is an acute, potentially life-threatening, IgE-mediated allergic reaction that occurs in previously sensitized people when they are reexposed to the sensitizing antigen. Symptoms can include stridor, dyspnea, wheezing, and hypotension. Diagnosis is clinical. Treatment is withepinephrine. Bronchospasm and upper airway edema may require inhaled or injected beta-agonists and sometimes endotracheal intubation. Persistent hypotension requires IV fluids and sometimes vasopressors. (See also Overview of Allergic and Atopic Disorders .) The prevalence of anaphylaxis is difficult to ascertain, but one study using 2 nationwide public surveys suggested that it was about 1.6% in the general adult population. Fatal anaphylaxis is far less common; it occurs in < 1 per million population (1). 