Allergic Reactions: Allergic Angioedema

This 41-year-old woman rushed to the emergency department with a swollen, blistered tongue and difficultly in swallowing and speaking. Twenty minutes earlier she had eaten fish (for the first time in her life). Her vital signs were normal.

This is an example of allergic angioedema, a form of localized submucosal or dermal swelling of the lips, tongue, eyelids, and even the pharynx. Antigenic stimuli include eggs, shellfish, peanuts, walnuts, and cow's milk; various drugs; insect bites; and infection. Serious allergic reactions, which occur within minutes to 2 hours, include acute angioedema of the upper airway, severe bronchial asthma, and anaphylaxis. These systemic responses result from the so-called immediate hypersensitivity reaction, in which IgE and histamine play essential roles. The onset is explosive, but resolution is rapid following administration of antihistaminic agents.

This patient responded to epinephrine and diphenhydramine and was advised never again to eat fish. She was followed closely thereafter and had no further problems.

(Case and photograph courtesy of Sunita Puri, MD.)