Hymenoptera-Sting Hypersensitivity

Anaphylactic reactions after a hymenoptera sting should be treated promptly with intramuscular epinephrine. Patients who have had such a reaction should carry injectable epinephrine and be referred to an allergist for insect-specific testing and subcutaneous immunotherapy if indicated. ForewordThis Journal feature begins with a case vignette highlighting a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they exist. The article ends with the authors' clinical recommendations.StageA 24-year-old woman reported that a bee stung her upper lip while she was drinking from a can of soda at a picnic. Within 5 minutes, her lips swelled, and she became hoarse and light-headed and had difficulty swallowing. Diffuse flushing and urticaria also developed. She was taken to a local emergency department and received intramuscular epinephrine and intravenous fluids along with H-1-antihistamines. Her symptoms resolved, and after 3 hours of observation she was discharged with an epinephrine auto-injector. How should her case be managed from this point forward? The Clinical Problem Although anaphylaxis due to an ... Hypersensitivity to Hymenoptera Stings Stings from insects of the order Hymenoptera are important causes of systemic allergic reactions. In sensitized persons, venom that is injected by a sting binds to venom-specific IgE on mast cells, with the subsequent release of mast-cell mediators that cause allergic reactions ranging from local reactions or urticaria to anaphylaxis and even death. Acute systemic allergic reactions typically occur very rapidly after a hymenoptera sting but may be delayed for several hours or be biphasic. The treatment of a hymenoptera-induced anaphylactic reaction (as for anaphylaxis caused by any other trigger) is the prompt administration of intramuscular epinephrine. Patients who have had a systemic reaction to an insect sting should be referred to an allergist-immunologist for testing for venom-specific IgE. Subcutaneous immunotherapy should be considered routinely in patients who have had a systemic allergic reaction to an insect sting and who have a positive test result for venom-specific IgE.