Researchers have discovered that a large amount of identifiable substances are contained in the urine of patients who have food allergies, which could help lead to early diagnosis of allergies through less-invasive testing.

Currently, to check for food allergies, a blood test or skin test, which involves inserting a needle in the skin, is needed. For finalizing the diagnosis, patients consume the foods they are suspected of being allergic to and their symptoms are observed.

“Urine tests wouldn't be burdensome even for small children," said Takahisa Murata, an associate professor at the Faculty of Agriculture at the University of Tokyo specializing in animal radiology, who led the team of researchers. "I want to develop testing methods that are easier to evaluate if there is a food allergy and to what degree the allergy symptom is.”

Murata and other researchers analyzed the urine of a mouse that is developing an egg allergy.

The team found that the more severe allergy symptoms the mouse has, the higher the concentrations of PGDM, a substance in urine, which is deeply related to an allergic response.

A mouse with a milk allergy also showed high concentrations of PGDM.

Moreover, when examining the urine of several patients diagnosed with a food allergy, a high concentration of PGDM was observed. In terms of patients with asthma or allergic rhinitis, their concentration levels in their urine were the same levels as people without those conditions.

The team's findings were published online by the British science magazine Scientific Reports on Dec. 15.