Peanut-allergic kids can build tolerance

In carefully conducted ongoing studies, giving peanut-allergic children peanuts in increasingly higher amounts over time has eased their allergic reactions to the nuts and even helped some of them lose their peanut allergies altogether.

"This gives other parents and children hope that we'll soon have a safe, effective treatment that will halt (peanut) allergies," Dr. Wesley Burks, chief of the division of pediatric allergy and immunology at Duke University Medical Center in Durham, North Carolina, noted in a university-issued statement.

However, in a telephone interview with Reuters Health, Burks cautioned that much more research is needed before peanut therapy can be used routinely. Peanut therapy "is really still only a clinical investigation; it's not something parents should try at home. We need a better understanding of the safety and how effective it is."

Five years ago, Burks and his colleagues began enrolling peanut-allergic children in a series of studies to see if incremental doses of peanut protein could change how the body's immune system reacts to its presence.

They started by giving participating children tiny amounts of peanut - as small as 1/1000th of a peanut daily. Eight to 10 months later, many of the children are now tolerating up to 15 peanuts per day.

"As we've gone beyond two and a half years of the peanut treatment, there are five children who seemingly have lost their sensitivity to peanuts," Burks said.

These children have been off the peanut treatment for about a month and continue to eat peanuts without allergic reactions. "We have allowed them to put peanuts in their diet and they are doing fine," Burks said.

In another study, a group of peanut -allergic children who have thus far completed a year of peanut treatment are able to tolerate about a handful of peanuts daily without any symptoms, whereas those that were not on the treatment (the placebo group) had allergic reactions after the equivalent of about a peanut and a half. As with the other study, the investigators plan to see how these children do once the peanut treatment is stopped.

About four million Americans have food allergies and allergies to peanuts and other tree nuts are the most common. "Some kids outgrow peanut allergy," Burks noted. "We'd like, hopefully, one day to be able to identify kids early in life who won't outgrow their peanut allergy and then start some type of peanut treatment early."

The research was presented Sunday at the annual meeting of the American Academy of Allergy Asthma and Immunology in Washington, D.C.

By Megan Rauscher
NEW YORK (Reuters Health)