Kiwifruit varieties not equally allergenic

Kiwifruit is regarded as an 'emerging allergen' in many countries due to the increasing number of individuals experiencing mild oral symptoms, characterised by rashes and mouth inflammation. Severe systemic reactions, including anaphylaxis, have also been reported in relation to kiwifruit. A new study has examined the differences in immune response to six kiwifruit varieties.

The varieties used in the study included the most widely sold cultivar 'Hayward', the popular 'Zespri Gold', the more recently introduced 'Jinatao' and 'Summer 3373' varieties, plus two other varieties that are reported as likely to become available on the market in future.

The 37 study participants comprised outpatients with known kiwifruit allergy recruited from the University Medical Centre in Zurich and University Hospital Zurich. Results of skin prick tests showed the Hayward and Eriantha varieties triggered the most marked reactions while Zespri Gold and Summer varieties were responsible for the mildest allergenic reactions.

Eleven of the participants also undertook a food challenge where they were gradually given small amounts of the Hayward, Zespri Gold and Summer varieties. Two of the participants experienced severe reactions during the challenge, with the Hayward variety appearing to be the most allergenic of those tested. Two participants in the food challenge experienced no adverse reactions.

Despite the findings from this small-scale study leading to suggestions that those with kiwifruit allergies may be able to selectively introduce certain varieties of the fruit into their diets, the researchers stressed that further investigations amongst a wider population is needed before any such recommendations could be made.

Reference: Le et al. 2010. Journal of Allergy and Clinical Immunology. DOI:10.1016/j.jaci.2010.10.003