The case is a 12-year-old girl. She was diagnosed with cashew nut allergy in infancy. She experienced the following allergic symptoms at age 11: sore throat after ingesting gummy bears containing citrus-derived pectin; sore throat, nausea, and severe abdominal pain after ingesting jelly containing yuzu (citrus junos) seeds and peel.Prick to prick test was positive for yuzu seeds and endocarp, lemon seeds, and citrus/apple pectin powder, and basophil activation test was positive for citrus/apple pectin powder. In both oral food challenge tests (OFCs) with jelly containing whole citron and lemon seeds, she had severe abdominal pain and vomiting. In OFC with citrus-derived pectin powder, she had mild sore throat. She ingested apple-derived pectin gummi at home and was asymptomatic.She was diagnosed with cashew nut-associated citrus seed allergy, most likely an allergy to citrin, based on her history and test. Patients with suspected pectin allergy should also be closely examined for citrus seeds.
Keywords: cashew nut; citrin; food allergy; pectin; seed.