[POLLEN FOOD ALLERGY SYNDROME IN A FIVE-YEAR-OLD BOY AFTER MOVING HOUSE AT THE FOOT OF THE MOUNTAIN: A CASE REPORT].

We report the case of a boy with a history of atopic dermatitis starting in infancy. At the age of four, his family moved into a newly built house at the foot of a mountain. One year later, he was diagnosed with Japanese Cedar pollinosis. During the same year, in March, he began to experience oral symptoms, hoarseness, and coughing, after eating multiple types of fruits and vegetables, like soybeans, apples, etc. His tests for Bet v1 and the pathogenesis-related protein-10 (PR-10) of the corresponding foods were positive; accordingly, he was diagnosed with Pollen Food Allergy Syndrome (PFAS). In order to investigate the relationship between pollen and food allergies, we counted the pollen grains dispersed at the patient's house during a period of one year and measured his specific IgE titers for pollen and food allergens every three months. We found a large amount of Japanese cedar, cypress, oak, and various other species of pollen dispersed at the patient's house. All counts were higher than the average pollen counts in the city of Fukuoka. After the seasonal dispersal of oak pollen, the patient's specific IgE antibody titers against Alder, Oak, Bet v1, Gly m4, and PR-10 protein group of fruits increased, although alder pollen was not detected. We thus inferred that the patient had developed PFAS by exposure to a large amount of Fagales species pollen, including oak.