Background: Hypersensitivity reactions to ingestion of figs (Ficus carica) and mulberries (Morus nigra and Morus alba) are considered uncommon and have never been reported as occurring in the same patient.
Objective: To determine whether hypersensitivity to figs and mulberries can induce cross-allergy.
Methods: We describe 3 cases of associated fig and mulberry allergy in 3 patients with multiple sensitizations to food allergens (mostly fruit) and airborne allergens. The presence of specific IgE was investigated by skin prick tests and radioallergosorbent tests.
Results: The 3 patients had a convincing clinical history of food allergy caused by eating fresh figs, and in all 3 cases clinical and/or laboratory evidence of sensitization to mulberries was also collected.
Conclusions: We reason that Ficus and Morus are closely related genera of the Moraceae family and speculate that hypersensitivity to figs and mulberries might be associated as the result of allergen cross-reactivity rather than mere coincidence.