Oral allergy syndrome to a jackfruit (Artocarpus integrifolia).

A 30-year-old man from the Philippines with pollen allergy noted the appearance of oral allergy syndrome (OAS) after eating raw apple, raw peach, raw celery, and recently, jackfruit (Artocarpus integrifolia), a tropical fruit which belongs to the Moraceae family (mulberry) and to the genus Artocarpus (breadfruit tree). Despite the patient's multiple sensitization in skin prick tests and in the Pharmacia CAP System to birch, grass, mugwort pollen, related fruits and vegetables, and jackfruit, in RAST-inhibition studies neither rBet v 1 nor rBet v 2 (profilin), the well-known cross-reacting allergenic components in OAS, could inhibit the specific IgE response to jackfruit. Whether the reaction to jackfruit is specific or whether other pollen-related, cross-reacting allergenic components exist should be investigated further.