Lipid transfer protein syndrome due to wild grape juice and various vegetables: A life‐threatening food allergen

Abstract

Lipid transfer proteins (LTP) are allergens contained in the outer layer of many plants. 1 While some patients with food allergy are sensitized to only one plant-derived substance, most tend to develop allergy to a wide variety of such foods and/or pollens, irrespective of botanical classification. This condition termed LTP syndrome 2 is considered to be related to primary sensitization to a food LTP allergen in the absence of both pollinosis 3,4 and a pollen source. 5,6 While LTP are common causes of food allergy in the Mediterranean area, 1,2 LTP syndrome is reported only rarely in Asia, where the habit of eating fruits and vegetables with the peel is unusual. Here, we report a case of LTP syndrome due to wild grape juice and various vegetables in a patient with mugwort pollinosis. Clinicians should be aware of LTP syndrome when making differential diagnosis, and take measures to prevent symptoms in patients. | C A S E REP ORTA 16-year-old Japanese male was referred to our department because of general urticaria, abdominal pain, and dyspnea that had occurred during exercise 30 min after eating a lunch box containing Chinese cabbage, bell peppers, and onions. Eight months after this first visit, the patient developed general urticaria, abdominal pain, and loss of consciousness immediately after drinking 50 mL of wild grape juice. Anamnesis revealed that he had sometimes experienced pruritic urticaria, sickness, and nausea after eating broccoli, tomato, and eggplant. His medical history included mugwort pollinosis from 13 years of age. The patient's total serum immunoglobulin (Ig)E level was 251 IU/mL, and specific IgE positivity for mugwort (16.7 UA/mL, class 4), ragweed (5.2 UA/mL, class 3), and duckweed (0.6 UA/mL, class 2) was detected, but that for birch, alder, cedar, cypress, and timothy grass was negative. Mugwort pollinosis in this patient was