Allergy to kiwi: is component-resolved diagnosis in routine clinical practice really impossible?

SUMMARY

Background: Kiwi allergy is frequent and can be the result of sensitization to a number of allergens showing different physicochemical characteristics. Component-resolved diagnosis of kiwi allergy is still unavailable in routine clinical practice. Objective: To investigate whether component resolved-diagnosis of kiwi allergy can be, at least in part, carried out by a proper combination of routinely available diagnostic tools. Methods: 63 adults with plant food allergy were studied. 36 were kiwi-allergic while 27 were kiwi-tolerant and served as controls. Patients and controls underwent SPT with commercial peach and kiwi extracts, and with a profilin-enriched date palm pollen extract (all by ALK-Abellò), and the measurement of IgE to birch, kiwi, and natural rubber latex. Results: The in-vitro test showed poor sensitivity and specificity, as it scored positive in about 50% of patients and controls irrespective of clinical allergy to kiwi. The kiwi SPT showed overall poor sensitivity; however, it scored negative in all subjects with pollen food-allergy syndrome, was weakly positive in some lipid transfer protein-hypersensitive/kiwi tolerant subjects and in one latex-sensitized subject, and strongly positive in all subjects with primary kiwi sensitization. Conclusion: SPT with this commercial kiwi extract sensitively and specifically detects patients reactingt o specific kiwi allergens. This can be useful to detect patients that are at risk of potentially severe reactions, particularly in case of co-sensitization to labile allergens, while we wait that the whole spectrum of kiwi allergens becomes available for routine in-vitro testing.