Garlic allergy in an infant: Identification of alliin lyase 1 and 2 as causative allergens

Garlic allergy is rare and is infrequently reported as a food allergy. This report details the case of a 13-month-old girl who developed an allergy to garlic. The consumption of a stew containing undercooked garlic triggered her allergic reaction. Blood tests revealed a garlic-specific IgE level of 10.3 kUA/L. In addition, in the skin prick test, a 4 × 4 mm, 2 × 2 mm, and 1 × 1 mm wheal was induced by raw garlic, garlic heated for 5 min, and garlic heated for 10 min, respectively. She had a known history of egg allergy. The foods consumed at the time did not contain eggs and included all other foods she had previously tolerated, except garlic. Therefore, we diagnosed her with a garlic allergy. We performed western blotting and mass spectrometric analysis and identified alliin lyase 1 and alliin lyase 2 as the major allergens. We further confirmed that the patient's sera reacted with recombinant alliin lyase 1 and 2. To our knowledge, this is the first report to accurately demonstrate the involvement of alliin lyase 1 and alliin lyase 2 in a patient with garlic allergy. Moreover, it highlights the differences in reactivity to garlic heated for different durations. In patients with garlic allergy, reactivity to heating time should be examined with skin prick tests.