Résumé : We report the case of an adult patient with occupational allergy to latex (. Hevea brasiliensis) associated with proven food allergy to buckwheat (. Fagopyrum esculentum). Immunological investigation demonstrated the presence of a 50. kDa allergen in both extracts; they were found to share common epitopes, reflecting their cross-allergenicity. The molecular function of this allergen has not yet been identified, but we suspect that it could be Hev b 13, a major latex allergen, which is not yet available for in vitro diagnosis.