Factors predicting the outcome of allergen-specific nasal provocation test in children with grass pollen allergic rhinitis

M Barreto; S Tripodi; S Arasi; M Landi; M Montesano; S Pelosi; E Potapova; I Sfika; V Villella; A Travaglini; M A Brighetti; P M Matricardi; S Dramburg

doi:10.3389/falgy.2023.1186353

Factors predicting the outcome of allergen-specific nasal provocation test in children with grass pollen allergic rhinitis

Front Allergy. 2023 May 26:4:1186353. doi: 10.3389/falgy.2023.1186353. eCollection 2023.

Authors

M Barreto¹, S Tripodi^{2

3}, S Arasi⁴, M Landi⁵, M Montesano¹, S Pelosi⁶, E Potapova⁷, I Sfika², V Villella², A Travaglini⁸, M A Brighetti⁸, P M Matricardi⁷, S Dramburg⁷

Affiliations

¹ NESMOS Department, Faculty of Medicine and Psychology, Pediatric Unit Sant'Andrea Hospital, "Sapienza" University, Rome, Italy.
² Pediatric Allergology Unit, Sandro Pertini Hospital, Rome, Italy.
³ Allergology Service, Policlinico Casilino, Rome, Italy.
⁴ Translational Research in Pediatric Specialities Area, Division of Allergy, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.
⁵ Institute for Biomedical Research and Innovation, Pediatric National Healthcare System, Turin, Italy.
⁶ TPS Production., Rome, Italy.
⁷ Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
⁸ Department of Biology, Tor Vergata University, Rome, Italy.

Abstract

Background: Nasal provocation testing (NPT) is a reference methodology to identify the culprit allergen in patients with allergic rhinitis. Selecting the right allergen for NPT is particularly difficult in poly-sensitized patients with seasonal allergic rhinitis (SAR). Predictors of NPT outcomes may facilitate the proper use of this test or even substitute it.

Objective: To identify predictors of grass pollen NPT outcome from an array of clinical data, e-diary outcomes, and allergy test results in poly-sensitized pediatric patients with SAR.

Methods: Poly-sensitized, SAR patients with grass pollen allergy, participating in the @IT.2020 pilot project in Rome and Pordenone (Italy), participated in a baseline (T0) visit with questionnaires, skin prick testing (SPT), and blood sampling to measure total (ImmunoCAP, TFS, Sweden) and specific IgE antibodies to grass pollen extracts and their major allergenic molecules (ESEP, Euroimmun Labordiagnostika, Germany). During the pollen season, patients filled the AllergyMonitor® e-diary app measuring their symptoms, medication intake, and allergy-related well-being via the Visual Analogue Scale (VAS). After the pollen season (T1), patients answered clinical questionnaires and underwent a nasal provocation test (NPT) with grass pollen extract.

Results: We recruited 72 patients (age 14.3 ± 2.8 years, 46 males) sensitized to grass and/or other pollens, including olive (63; 87.5%) and pellitory (49; 68.1%). Patients positive to grass pollen NPT (61; 84.7%), compared to the negative ones, had worse VAS values in the e-diary, larger SPT wheal reactions, and higher IgE levels, as well as specific activity to timothy and Bermuda grass extracts, rPhl p 5 and nCyn d 1. A positive NPT to grass pollen was predicted by an index combining the specific activity of IgE towards Phl p 5 and Cyn d 1 (AUC: 0.82; p < 0.01; best cut-off ≥7.25%, sensitivity 70.5%, specificity: 90.9%). VAS results also predicted NPT positivity, although with less precision (AUC: 0.77, p < 0.01; best cut-off ≥7, sensitivity: 60.7%, specificity: 81.8%).

Conclusions: An index combining the specific activity of IgE to rPhl p 5 and nCyn d 1 predicted with moderate sensitivity and high specificity the outcome of a grass pollen NPT in complex, poly-sensitized pediatric patients with seasonal allergic rhinitis. Further studies are needed to improve the index sensitivity and to assess its usefulness for NPT allergen selection or as an alternative to this demanding test procedure.

Keywords: component-resolved diagnostics; e-Diary; nasal provocation test (NPT); pollen allergy; precision medicine; seasonal allergic rhinitis.

Grants and funding

SA was supported by the EAACI Fellowship Award of the European Academy of Allergy and Clinical Immunology. The study was supported by an unrestricted grant from EUROIMMUN (grant no 118583). The Informatics Platform AllergyCARD and the app AllergyMonitor® were kindly provided by TPS Production, Rome, Italy.