For parents of a child with a suspected peanut allergy, everyday activities like grocery shopping, dining out and birthday parties can come with added worry. But new research suggests some families may be avoiding peanuts unnecessarily.
An Australian study found that about 35% of infants who had previously reacted to peanuts and tested positive for an allergy showed no reaction when given peanuts under medical supervision. The findings, published in The Journal of Allergy and Clinical Immunology: In Practice, suggest that some children may be mistakenly considered allergic, leading to dietary restrictions they don't actually need.
Researchers reviewed the medical records of 1,275 infants participating in an Australian peanut allergy treatment program. Of those, 778 underwent an oral food challenge, a test in which children eat gradually increasing amounts of peanut while medical professionals watch for allergic reactions.
The results were surprising. Although all the infants tested had a history of reacting to peanuts and positive allergy test results, 271 showed no reaction during the food challenge. Those children were considered able to tolerate peanuts and could have their suspected allergy diagnosis removed.
"We found more than one third of infants who were suspected to have peanut allergy based on their history and initial tests no longer reacted when they underwent a supervised food challenge," said Dr. Tim Brettig of the Murdoch Children's Research Institute.
The findings highlight something many parents may not realize: A positive allergy test doesn't always mean a child is allergic to a food.
Common skin and blood tests can indicate that a child's immune system recognizes peanuts, but they cannot always predict whether eating peanuts will trigger a reaction. That's why doctors also consider a child's symptoms and medical history when making a diagnosis.
A supervised food challenge can help settle the question. And getting the diagnosis right matters. An unnecessary allergy label can mean years of avoiding foods, checking ingredients and worrying about accidental exposure.
However, the results don't mean parents should try reintroducing peanuts on their own. Of the 778 infants who underwent food challenges, 507 had allergic reactions, including 61 who experienced anaphylaxis, a potentially life-threatening reaction. All were successfully treated by the medical teams.
Food challenges should only be performed under appropriate medical supervision, where serious reactions can be treated immediately.
The researchers also caution that their findings don't necessarily mean the children had outgrown their allergies. Some may never have been truly allergic, while others may have developed tolerance over time. The study couldn't determine which explanation applied.
And because the research focused on infants referred to a specialized treatment program, the findings don't mean that 35% of all children diagnosed with peanut allergies have been misdiagnosed.
Still, the results raise an important question about how suspected food allergies are confirmed, particularly before children begin long-term treatment or years of dietary restrictions.
For families dealing with a suspected peanut allergy, the findings offer a reason to discuss the diagnosis with a pediatric allergist and ask whether a supervised food challenge might be appropriate.
The study was supported by Australia's federally funded National Allergy Centre of Excellence and philanthropic organizations supporting the Murdoch Children's Research Institute. Additional support came from Australian government and research fellowship programs. Senior researcher Kirsten Perrett reported research grants and institutional consulting fees from several pharmaceutical and biotechnology companies outside the submitted work.