Background: Serum allergen-specific immunoglobulins E (IgE) play a key role in allergy diagnosis along with clinical history and physical examination. Nowadays, allergen multiplex assays allow complex polyallergic cases to be solved as they assess up to 300 allergen-specific IgE. Recently, machine learning has emerged as a trending tool in medicine. The aim was to build a nationwide, open-access database to create an algorithm that could predict allergy diagnosis, severity, category (airborne, food, venom) and culprit allergens. Methods: A retrospective national database was created by the French Society of Allergology in collaboration with AllergoBioNet and the Health Data Hub. Collected data were de-identified patient profiles with five demographic items, twenty clinical items and sIgE results of one allergen multiplex assay. An international crowdsourced machine learning competition was hosted by the Trustii.io platform. Criteria for algorithm evaluation were the F-score (a measure of a model’s accuracy on a dataset) and external validation on patient profiles outside the database (80%-20%, respectively). Results: Data were collected from 4271 patient files. Two hundred and ninety-two data scientists competed with 3135 algorithms. The best F-scores were comprised between 78% and 80%. Models associated with the highest F-scores used gradient boosting classifiers such as LightGBM, CatBoost, XGBoost adapted for tabular datasets with categorical features. Conclusions: We report here the first artificial intelligence models applied to allergen multiplex arrays interpretation in a nationwide real-world database built to be open access. With F-scores close to 80%, the French Allergen Chip Challenge paves the way for a diagnostic prediction tool for practicing allergists.

Background: The aim of this study was to compare the technical and clinical effectiveness of two platforms (Phadia ImmunoCAP™ and Hycor NOVEOS) for the measurement of IgE specific for 10 food allergens. Methods: 289 patients, as part of allergy diagnosis or of their follow-up were included and tested for IgE specific for six food allergen extracts (egg white, cow’s milk, peanut, hazelnut, fish, shrimp) and four molecular allergens (Gal d 1, Bos d 8, Ara h 2, Cor a 14). Specific IgE measurements were carried out using the ImmunoCAP™ and NOVEOS methods. Food allergy diagnosis was established according to international guidelines. Results: A very good correlation (rho>0.9) was present between the two platforms, while specific IgE concentrations measured with NOVEOS were consistently lower (mean -15%) than with ImmunoCAP™. NOVEOS provided higher overall odd-ratios and relative risks for allergen extracts than ImmunoCAP™, but the difference was not significant. When all ten allergens were considered, NOVEOS provided better ROC curves (p=0.03) and thus, had a better ability to establish the true value. Finally, we found that the most discordant results were observed with hazelnut and peanut extracts, and were related to cross-reactive carbohydrate determinants on these two ImmunoCAP™. Conclusions: Specific IgE determination by either ImmunoCAP™ (odd-ratios of allergy = 25.1) or NOVEOS (odd-ratios of allergy = 33.0) is similarly highly informative on the risk of allergy in the selected population. The NOVEOS platform presents the advantage of being less affected by unwanted reactivity due to IgE specific for carbohydrate determinants, while requiring a ten-fold lower test sample volume.

Background: Allergy is witnessing major advances, in particular with the advent of biological therapies for treating allergic diseases. Given the novelty of these therapeutics, we aimed to explore by a worldwide survey, the prescription and the management of hypersensitivity reactions (HR) of biological agents (BA) in Allergy. Method: We built up an anonymous online questionnaire, sent out by mail and social media and circulated for 40 days. Results: 348 responses were from 59 countries, with a majority from Europe (62.6%). 97% of responders practiced allergy and 48.5%, exclusively so. Allergy was mentioned as a full specialty in 69.5 % of cases. 71% of responders confirmed the right of prescription of BA for allergists in their country and 78.4 % prescribed BA in their clinical practice. Europe included almost all the allergists who did not have the right of prescribing BA (95.5%), specifically France (91%). The most prescribed BA were Anti IgE (78.1%) and anti IL5 (43.9%). The most declared HR to BA were local reactions (74.1%) followed by anaphylaxis like symptoms (6.8%) and delayed exanthemas (5.1%). Desensitization was considered in 18.9% of cases. These HR were reported in 48.8% of cases. Conclusion: Although BA are now a pillar in the treatment of allergic diseases and allergists are familiar with management of HR associated with BA, their prescription is not authorized for allergists in all countries. BA showed to be generally safe but HR, which may be severe, could occur with a lack of consensus on the management.