Back to basics: likelihood ratios for olive and grass pollen specific IgE in seasonal allergic rhinitis

Bárbara Manzanares; Rafael González; Pilar Serrano; Ana Navas; Corona Alonso; Lourdes Fernandez; Aurora Jurado; Carmen Moreno-Aguilar

doi:10.3389/falgy.2023.1241650

Back to basics: likelihood ratios for olive and grass pollen specific IgE in seasonal allergic rhinitis

Front Allergy. 2023 Oct 4:4:1241650. doi: 10.3389/falgy.2023.1241650. eCollection 2023.

Authors

Bárbara Manzanares^{1

2

3}, Rafael González^{1

2

4}, Pilar Serrano^{1

2

4}, Ana Navas^{1

2}, Corona Alonso^{1

2}, Lourdes Fernandez^{1

2}, Aurora Jurado^{1

2

4}, Carmen Moreno-Aguilar^{1

2

4}

Affiliations

¹ Maimonides Biomedical Research Institute of Córdoba (IMIBIC), Reina Sofia University Hospital/ University of Córdoba, Córdoba, Spain.
² Department of Immunology and Allergy, Reina Sofia University Hospital, Córdoba, Spain.
³ Postdocs CSYF, Code RH-0060-2020, European Social Fund, Sevilla, Spain.
⁴ National Network ARADyAL, Health Institute Carlos III, Madrid, Spain.

Abstract

Introduction: Specific IgE (sIgE) is merely a sensitization marker that cannot be used for allergy diagnosis if there are no associated clinical symptoms. As of 2023, there is still no evidence regarding the quantity of sIgE necessary to confirm or exclude clinical disease. Therefore, this study aimed to calculate cut-offs for sIgE, allowing us to effectively diagnose olive or grass pollen allergy and select allergenic immunotherapy (AIT) candidate patients in a region under high olive and grass allergenic pressure.

Methods: An observational retrospective study consisting of the review of electronic medical records from 1,172 patients diagnosed with seasonal rhino-conjunctivitis and suspected allergy to olive or grass pollen. Symptoms correlated with sIgE to Poaceae and Oleaceae whole extracts and sIgE to genuine allergenic components were evaluated. Optimal cut-off values were calculated using receiver operating characteristic curves. Relevant clinical symptoms and AIT indications were taken into consideration when determining the clinical allergy diagnosis.

Results: sIgE to Lolium showed the best area under the curve (AUC) for both diagnosis (0.957) and an indication of AIT (0.872). The optimal cut-off values for grass diagnosis and AIT indication were 1.79 kUA/L and 8.83 kUA/L, respectively. A value of 5.62 kUA/L was associated with a positive likelihood ratio (LR) of 10.08 set for grass allergy. Olea sIgE showed the best AUC for the diagnosis (0.950). The optimal cut-off for diagnosis was 2.41 kUA/L. A value of 6.49 kUA/L was associated with a positive LR of 9.98 to confirm olive pollen allergy. In regard to immunotherapy, Ole e 1 sIgE showed the best AUC (0.860). The optimal cut-off was 14.05 kUA/L. Ole e 1 sIgE value of 4.8 kUA/L was associated with a 0.09 negative LR to exclude olive AIT indication.

Conclusions: The sIgE cut-offs found in this population under high olive and grass allergenic pressure reduce the gap between sensitization and clinical allergy, providing a new tool for the diagnosis of seasonal allergic rhinitis/asthma and helping to discriminate patients who will benefit from AIT.

Keywords: Olea; Poaceae; allergen immunotherapy; cut-off values; likelihood ratios; seasonal allergic rhinitis/asthma.

Grants and funding

The first author has been awarded a contract funded by Thermofisher Scientific to conduct the study (Research project number CCB.0160). Thermofisher Scientific did not have any role in the study design; collection, analysis, and interpretation of data; in the writing of the report; nor in the decision to submit the article for publication.