How molecular diagnosis can change allergen-specific immunotherapy prescription in a complex pollen area

The identification of disease-eliciting allergens is a prerequisite for accurate prescription of allergen-specific immunotherapy (SIT). The aim of this study was to determine whether molecular diagnosis (MD) may change indication and allergen prescription of SIT.

A total of 141 patients with allergic rhinoconjunctivitis and/or asthma sensitized to pollen with or without concomitant food allergy were included. Skin prick testing with a panel of aeroallergens and a microarray-based panel of allergens (ISAC(®); Phadia, Sweden) was performed in all patients. Prior to learning the results of molecular diagnosis, three of the authors reached a consensus on the indication of SIT and use of allergens following EAACI recommendations, basing their judgment on clinical history and skin prick test results before and after obtaining the ISAC results. The agreement coefficient (kappa index) was used to analyze the results.

Fifty-nine percent of the patients were women with a mean age of 31 ± 13.63. Agreement in SIT indication before and after ISAC(®) results was found in only 62 (46%) patients (kappa = 0.1057 ± 0.0413). Concerning allergens used in the most common prescriptions before and after MD results, we obtained the following results: κ = 0.117 ± 0.0825 for grass; κ = 0.1624 ± 0.0639 for olive; κ = 0.0505 ± 0.0548 for olive and grass; κ = 0.1711 ± 0.0471 for grass and cypress; κ = 0.1897 ± 0.0493 for grass and London plane; κ = 1 ± 0.0842 for olive and cypress, and κ = 0.3586 ± 0.0798 for other combinations.

There was very low agreement concerning indication and use of allergens for SIT before and after performing MD. This discrepancy emphasizes the usefulness of MD, at least in areas of complex sensitization to pollen, in determining correct indication of SIT.