Systemic Symptoms of PR-10-Related Pollen Food Allergy Syndrome High in Pediatric Patients Surveyed

New research has highlighted the prevalence of systemic symptoms associated with PR-10 pollen food allergy syndrome (PFAS) in pediatric patients.1

PFAS is generally recognized as a mild condition associated with oral allergy syndrome (OAS), but it is increasingly understood to be a condition that can cause systemic symptoms. Reports of systemic symptoms associated with PFAS have been reported in adults, but the incidence in children remains unknown,” lead investigator Masaaki Hamada, Department of Pediatrics, Yao Municipal Hospital, Osaka, Japan, and colleagues wrote.1

Hamada and colleagues conducted 2 surveys, 1 for patients diagnosed with PR-10-related PFAS at medical institutions and another for elementary and junior high school children whose parents completed an online questionnaire, to investigate if the medical institutions had patients with more severe allergies and the incidence of misdiagnoses among school children. They collected data on allergenic foods/symptoms, incidence of OAS, and systemic symptoms in patients with PR-10-related PFAS allergic to Rosaceae fruits and soybeans.

Altogether, 221 patients were surveyed at medical institutions and 29,906 were surveyed online. Of the patients at medical institutions, 205 developed allergic symptoms to Rosaceae fruits and 86 developed allergic symptoms to soybeans. The soybean group had a significantly higher incidence of systemic symptoms (n = 43; 50.0%) than the Rosaceae fruits group (n = 205; 21.0%; P >001).1

Of the 3309 (11.1%) school children whose parents responded to the online survey, 202 had PR-10-related PFAS, 194 developed allergic symptoms to Rosaceae fruits and 29 to soybeans. Again, the soybean group had a significantly higher incidence of systemic symptoms (n = 12; 41.4%) than the Rosaceae fruits group (n = 46; 23.7%), although this difference was not significant (P = .067).1

“In conclusion, PR-10-related PFAS is a type of food allergy that requires management of systemic symptoms, as systemic reactions occur in 20% of patients with common allergenic foods such as Rosaceae fruits and in nearly half of patients with soybeans. There may be a certain number of patients with PR-10-related PFAS who are seeking treatments other than the common approach of allergen elimination,” Hamada and colleagues concluded.1

The investigators noted several limitations of the study. First, pollen sensitization was not confirmed in the student survey, but similar rates of systemic symptoms in both surveys support some validity. Second, symptom assessment relied on interviews, which may involve recall bias; however, detailed questionnaires likely helped mitigate this, especially given PFAS symptoms vary seasonally. Third, the low response rate to the online survey limits estimates of general prevalence, though it still provides insight into PFAS among children with food allergies. Finally, the proportion of PFAS cases per institution in the multicenter survey is unknown, potentially introducing selection bias.

In Japanese children with PFAS, Rosaceae fruits that cross-react with birch pollen are the primary driver of allergy. Patients with PR-10-related PFAS also develop allergenic symptoms to Rosaceae fruits and soybeans that cross-react with birch pollen. It is important to note that sensitizing pollens and cross-reactive allergenic foods associated with PFAS vary by region and this study was conducted in Japan.2

REFERENCES

1. Hamada M, Kameda M, Takaoka Y, et al. Evaluation of the incidence of systemic symptoms in PR-10-related pollen-food allergy syndrome in Western Japan. Pediatr Allergy Immunol. 2025;36(5):e70104. doi:10.1111/pai.70104

2. Takemura Y, Takaoka Y, Arima T, et al. Association between fruit and vegetable allergies and pollen-food allergy syndrome in Japanese children: a multicenter cross-sectional case series. Asia Pac Allergy. 2020; 10:e9.