More Anaphylactic Reactions Than Previously Reported

A Mayo Clinic study reported that anaphylactic reactions reported in emergency room visits increased from 30,000 to 50,000 over the decade from 1990 to 2000.

The study, entitled "The etiology and incidence of anaphylaxis in Rochester, Minnesota," by Wyatt W. Decker, M.D., chief of emergency medical departments at the Mayo Clinic in Rochester, Minn. and his team, reported that there were 50 emergency room visits per 100,000 population per year caused by anaphylaxis.

The actual increase is probably smaller than a two-thirds rise because reporting was much better than in earlier studies.

"We don't think the incidence of anaphylaxis has doubled, but through the Rochester Epidemiology Project we were able to much more meticulously identify cases which in other studies might not have been identified," says Dr. Decker. "So this study gives us a more accurate picture of the magnitude of the problem. Still, we did see about a 10 percent increase in cases of anaphylaxis over the 10-year period of the study."

Other findings from the study include:

-- Children ages 0 to 19 are at the highest risk for anaphylaxis.
-- Insect stings accounted for 19 percent and medications for 14 percent of cases. The rest were due to some other cause (e.g., cats, latex, unknown).
-- None of the medical records involved a fatal reaction.