A simple test can predict whether your child will outgrow their peanut allergy: ScienceAlert

The results of a new study from the Murdoch Children’s Research Institute in Melbourne, Australia, could help doctors predict whether a child will outgrow their peanut allergy by monitoring changes in their peanut allergy. antibody levels.

Antibodies are proteins produced by your immune system to recognize unwanted substances. They bind to these intruders and inactivate them, or recruit immune cells to destroy them.

People with allergies produce too much of certain antibodies when they are exposed to an allergen, a substance to which their immune system has become sensitized. These somewhat allergen-specific antibodies are good indicators of the type and severity of a person’s allergy.

And yet, when it comes to childhood peanut allergies, details on these antibodies as biomarkers are lacking.

“Little was known prior to this research about the possibility of using antibodies as biomarkers to naturally resolve peanut allergy during the elementary school years,” says population health graduate student Kayla Parker. , from the Murdoch Children’s Research Institute.

Parker and his team looked for long-term trends in children whose peanut allergies persisted or disappeared before age 10 — specifically, their levels of two types of antibodies that respond to peanuts and the main allergen found in peanuts, a protein called Ara h 2.

She hopes the new research will help allergy specialists identify which children might have a persistent peanut allergy and which ones might grow out of it.

The findings are based on a much larger data set from an ongoing longitudinal study of food allergies that began in 2007, called HealthNuts.

As part of this data, the researchers focused on 156 children from Melbourne, who joined the study from 2007 when they were 12 months old. with confirmed peanut allergies. Over the next few years, these children received questionnaires, skin tests, blood tests and oral food challenges at 4, 6 and 10 years.

Two-thirds of these children had not cured their peanut allergy by age 10, but the vast majority of those who did had achieved tolerance by age 6.

The team found that it was not the antibody levels themselves that were linked to the persistence or resolution of allergies, but rather a change in the level of each type of antibody over time. .

“We found that longitudinal changes were more useful in predicting which children would be on the path to resolution of a peanut allergy than relying on a single snapshot at a single point in time,” Parker says.

Children whose peanut allergies persisted tended to have increased skin test reactions and increased levels of peanut sIgE and Ara h 2 sIgE antibodies over the years.

Meanwhile, children whose peanut allergies eventually resolved followed an entirely different trajectory. Over the years, their reactions to skin tests eased, as did their levels of Ara h 2 sIgE antibodies, while levels of peanut sIgG antibodies decreased.₄ and Ara h 2 sIgG₄ increase.

It appears that some children with peanut allergies experience a shift in antibodies during childhood, which correlates with the persistence or resolution of their allergy.

The nature of this link remains unclear, but it could help allergists identify which of their patients are likely to need continued testing to monitor the status of their allergy, to see if it is indeed improving, and which of these will likely need continued review. avoid peanuts long term.

“(Children) with high or increasing levels of these biomarkers are less likely to spontaneously overcome their peanut allergy and could be prioritized for possible early treatment options if they are available,” Parker said.

Over the past few decades, many schools have completely banned this risky legume from lunch boxes. the evidence that these general bans help prevent allergic reactions is missing. Allergy experts say these bans can also give parents and children a false sense of security.

Research shows that more effective approaches include hand washing, discouraging food sharing, and limiting unexpected sources of peanut exposure, such as certain materials for craft and science projects. It is also essential to train school staff on how to respond to serious allergic reactions.

There is currently no routine treatment for peanut allergy, so children suffering from these allergies should strictly avoid peanuts.

However, the researchers behind this study point out that clinical trials exploring new treatment options are available to Australian families, listed in the National Allergy Center of Excellence Allergy Studies Directory.

This research was published in Allergy.