INMUNOCAT study: The impact of molecular diagnosis on immunotherapy prescription in pollen polysensitized patients from Catalonia

Abstract

Background: Recognition of specific allergens triggering immune response is key for the appropriate prescription of allergen-specific immunotherapy (SIT). This study aimed at evaluating the impact of using the commercially available microarray ImmunoCAP^TM ISAC 112 (Thermo Fisher Scientific) on the etiological diagnosis and SIT prescription compared to the conventional diagnostic methods in patients with allergic rhinitis/rhinoconjunctivitis and/or asthma.

Methods: 300 patients with respiratory allergic disease, sensitized to three or more pollen aeroallergens from different species, as assessed by a skin prick test (SPT) and specific IgE assays (sIgE), were included in this multicentric, prospective observational study. SPT and a blood test were performed to all patients. Total serum IgE and sIgE (ImmunoCAPTM) for allergens found positive in the SPT and sIgE allergen components (ImmunoCAPTM ISAC 112) were measured.

Results: According to SPT results, the most prevalent pollen sensitizers in our population were Olea europaea followed by grass, Platanus acerifolia and Parietaria judaica. The molecular diagnosis (MD) revealed Ole e 1 as the most prevalent pollen sensitizer, followed by Cup a 1, Phl p 1, Cyn d 1, Par j 2, Pla a 1, 2, and 3 and Phl p 5. Immunotherapy prescription changed, due to MD testing, in 51% of the cases, with an increase of prescription of SIT from 39% to 65%.

Conclusion: The identification of the allergen eliciting the respiratory disease is essential for a correct immunotherapy prescription. The advances in allergen characterization using methods, such as the commercial microarray ImmunoCAP^TM ISAC 112, can help clinicians to improve SIT prescription.

Keywords: asthma; change; immunotherapy; molecular diagnosis; personalized medicine; pollen polysensitized patients; rhinitis; rhinoconjunctivitis.

FIGURE 1

Pollen sensitization profile of the cohort. (A), Frequency of positive reactions to most common allergens across age groups, according to skin prick tests. (B), Frequency of positive reactions to the most common molecular allergens according to ImmunoCAP^® ISAC; allergens were classified into: specific allergens (leading to genuine sensitization) and cross‐reactive allergens. (C), Complete sensitization profile according to ImmunoCAP^® ISAC across age groups. Pink: <11 years; green: 11–25 years; blue: >25 years; grey: all subjects.

FIGURE 2

Comparison between ImmunoCAP^® sIgE and SPT results for the most common pollen allergens. Graph highlights the frequency of negative SPT in positive ImmunoCAP^® sIgE patients. Peach LTP = lipid transfer protein.

FIGURE 3

Changes in the immunotherapy (SIT) prescriptions following molecular diagnosis. (A), Percentage of patients who were prescribed SIT (candidates for immunotherapy) versus percentage of patients that were not prescribed SIT (non‐candidates for immunotherapy) before and after molecular diagnosis. (B), Changes in the SIT prescriptions following molecular diagnosis: patients who became eligible for SIT (“No to Yes”: 33%), patients who were no longer considered candidates for SIT (“Yes to “No”: 6%), or patients who were still eligible for SIT, but had their SIT prescription adjusted. (C and D), Adjustments in the SIT prescription in terms of the allergens (C) composition and (D) number.