Peanuts are one of the foods most frequently triggering allergic reactions, which can cause symptoms such as itching, swelling, redness, and shortness of breath immediately after consumption or contact, potentially becoming life-threatening.
In countries like the United States, the United Kingdom, and Australia, food allergies are relatively common in children, with estimates suggesting that about 2% of children in these regions have the condition. Specifically in Australia, this proportion reaches approximately one in every 30 children.
A recent investigation conducted in Australia sought to verify the accuracy of these diagnoses. The findings, published in November in the scientific journal The Journal of Allergy and Clinical Immunology: In Practice, suggest that about one-third of babies diagnosed with peanut allergy may, in fact, not have this allergy.
The study analyzed data from 1,275 babies under 18 months old who participated in a national peanut allergy treatment program offered by ten public Australian pediatric hospitals, covering the period between 2024 and 2025. The initial diagnosis is usually based on the history of peanut reaction combined with skin tests, where a small sample of peanut extract is applied to the skin to observe responses.
In the 778 babies, researchers administered the oral challenge test to confirm the diagnosis. This procedure involved the children ingesting increasing doses of peanut protein under medical supervision in a suitable location. The administered doses ranged from 15 mg to 1,300 mg of protein, equivalent to approximately one teaspoon, distributed in up to seven applications.
At the end of the experiment, 271 babies, corresponding to about 35% of those who underwent the test, showed no signs of allergic reaction, meaning that in more than one-third of cases, the initial diagnosis was not confirmed.
The authors argue that traditional allergy tests do not always accurately reflect the allergic status in babies, given that their immune system is still developing. They observe that many tests only identify sensitization to the food, and not necessarily confirm an allergy. Furthermore, it is possible that some of these children overcame the allergy between the time of diagnosis and the test, which was conducted about six months after the first reaction.
Practically all babies who showed reactions during the experiment were subsequently included in oral immunotherapy with peanuts, part of the program. This therapy consisted of consuming small daily amounts of the food to try to increase tolerance, with the initial dose determined by the results of the oral challenge test.
The results of this immunotherapy were positive, as 97.5% of participants managed to start treatment at the dose established by the test. The researchers advocate that the oral challenge test should precede immunotherapy, even though the latter can normally begin without such a test. They state that prior testing can prevent unnecessary treatments.
It is crucial that the procedure takes place in a controlled environment; during the study, 61 babies suffered anaphylaxis and required adrenaline administration. Despite this, the authors maintain that the oral challenge test should be routinely incorporated into the assessment of peanut allergy in babies, regardless of the therapeutic approach chosen.
