Objective: The purpose of this study was to investigate crossreactivity between latex and foods, to identify crossreacting IgE binding proteins, and to assess the clinical significance.
Methods: Forty-seven latex allergic patients and 46 non-latex allergic patient controls were studied. Allergen sensitization was determined by skin-prick testing (SPT) and allergenic proteins were identified by immunoblot reactivity and amino acid sequence analysis.
Results: Immunological reactivity to foods was found to be common, occurring in 33 latex-allergic individuals but in only seven controls (P < 0.000001); 100 of 376 (27%) food skin-prick tests were positive in the latex-allergic subjects. Twenty-seven out of 100 positive food SPTs were associated with clinical symptoms. Seventeen patients manifested a clinical allergy to at least one food including 11 with anaphylaxis, and 14 with local sensitivity reactions. Positive food skin tests occurred most frequently with avocado (53%), potato (40%), banana (38%), tomato (28%), chestnut (28%), and kiwi (17%). Latex-allergic patients (23%) recognize a protein that had sequence homology to a broad class of plant proteins known as patatins. Crossreactivity between latex and several potato proteins was observed by immunoblot inhibition analysis.
Conclusions: Sensitization to latex has extensive crossreactivity with certain foods and leads to clinical allergic reactions. Potatoes and tomatoes are newly reported cross-reacting foods. Plant proteins with structural homology to latex proteins may predispose to food allergy.