Analysis of food-allergic and anaphylactic events in the National Electronic Injury Surveillance System

Background The National Electronic Injury Surveillance System (NEISS) captures a nationally representative probability sample from hospital emergency departments (EDs) in the United States. Objective Emergency department data from NEISS were analyzed to assess the magnitude and severity of adverse events attributable to food allergies. Methods Emergency department events describing food-related allergic symptomatology were identified from 34 participating EDs from August 1 to September 30, 2003. Results Extrapolation of NEISS event data predicts a total of 20,821 hospital ED visits, 2333 visits for anaphylaxis, and 520 hospitalizations caused by food allergy in the United States during the 2-month study period. The median age was 26 years; 24% of visits involved children ≤5 years old. Shellfish was the most frequently implicated food in persons ≥6 years old, whereas children ≤5 years old experienced more events from eggs, fruit, peanuts, and tree nuts. There were no reported deaths. Review of medical records found that only 19% of patients received epinephrine, and, using criteria established by a 2005 anaphylaxis symposium, 57% of likely anaphylactic events did not have an ED diagnosis of anaphylaxis. Conclusion Analysis of NEISS data may be a useful tool for assessing the magnitude and severity of food-allergic events. A criteria-based review of medical records suggests underdiagnosis of anaphylactic events in EDs.