"The Food Challenge is what we call the gold standard for diagnosing food allergy," said Dr. David Fleischer, an assistant professor of pediatrics at National Jewish Hospital. "It is the best test for determining whether someone has a food allergy."
Fleischer and his colleagues discovered, in a new landmark study, that more than half the foods triggering positive blood tests could, in fact, be added safely back to the diets of patients based on food challenges.
The study seems to indicate there may be thousands of Americans, perhaps more, who aren't eating food that they probably could eat safely.
"The problem is that a lot of people think they have food allergies; there are a lot of people that have reactions to food out there, but not every reaction is a food allergy," Fleischer said.
It was that type of reaction that brought 5-year-old Ashley Garcia to the emergency room after eating an ice cream cone with nuts. The suspicion: a potentially life-threatening allergy to peanuts.
"By the time we got there, her eyes were bloodshot red and it seemed like there was a whole other layer of skin," said her father, Sergio Garcia. "She broke out in a rash."
Ashley's parents decided to allow her to undergo a food challenge, even though the risk was another dangerous allergic reaction.
"It hit me last night, that if it's going to happen, this is probably the best place for it to happen," Garcia said.
Their goal is modest.
"Ashley's goal is that she can eat Reese's peanut butter cups," Garcia said.
The food was introduced gradually, beginning with only a half gram of peanut butter. The portion was increased, and a nurse checked for allergic reactions after each serving. Finally she got the peanut butter cup.
"It's good," she said.
"[This] tells me she should be able to go and have peanut butter," said Sandy White, a registered nurse at the National Jewish Hospital. "She should be able to be around peanuts and not have a reaction."
Food challenges may be the emerging standard, but they can cost thousands of dollars; less accurate blood tests typically run about $300.
"It is a burden to do on a daily basis," Malka said. "It takes time, it takes staff, and there's always a risk associated with any food challenges ... because of an allergic reaction. But if it's done in the right setting, with the right testing behind it, it's a very safe test to do."
Now, Becky Ringstrom's kitchen is loaded with foods she calls, "Blake-safe." Currently, Blake is allowed to eat about 15 foods. Last fall, he sat down to his very first Thanksgiving meal.
"So many of the foods that he was able to gain, the sweet potatoes, the corn and the mashed potatoes, the turkey, they were all passes for him," Ringstrom said. "So to know that we can ... just sit down as a family and eat it, it was just overwhelming."
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