New research is putting the ‘pee’ in peanut allergy testing

It is now widely known in Australia that food allergies are relatively common and much has been done to prevent harm, such as better warning labels on foods and better understanding within the hospitality industry.

But finding out what food someone is allergic to in the first place can still be tricky.

Allergy testing can be a complex process; it may include a specific IgE blood test to look for antibodies in the bloodstream linked to an allergic response.

Skin prick testing may also be used and involves scratching the surface of the skin and applying a small amount of various allergens then monitoring any reaction.

An oral challenge test, where certain foods are consumed and symptoms monitored, might also be needed to confirm an allergy.

However, some recent research in Japan might point towards a simpler, less invasive avenue for allergy testing.

Researchers at the University of Tokyo tested the urine of mice with allergies to egg and milk. They wanted to see if urine testing could help to pick up an allergy and determine the level of severity.

They found that the compound prostaglandin D2 metabolite (PGDM) was present in high levels in the urine of allergic mice, and higher levels of PGDM were consistent with a more severe allergy.

The team also tested human urine samples comparing the urine of patients with and without allergies.

Importantly the raised levels of PGDM were only found in people with food allergies, not healthy volunteers or those with other allergic conditions such as asthma, allergic rhinitis (hay fever), and atopic dermatitis.

It is early days still, but this finding could be a useful step in streamlining diagnosis of allergies, particularly in young children who may find the process of skin prick testing and oral challenges distressing.

Food allergies affect 1-2% of adults and 4-8% of children under 5 in Australia. While fantastic progress has been made recently in search of a cure, early diagnosis remains important to ensure that precautions can be taken to minimise the risk of exposure to a potentially life-threatening food.