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Real-World Safety Analysis of Preschool Tree Nut Oral Immunotherapy
Stephanie C Erdle1, Victoria E Cook2, Scott B Cameron2
1Division of Allergy and Immunology, Department of Pediatrics, University of British Columbia, BC Children's Hospital, Vancouver, British Columbia, Canada.
Insights
Tree nut oral immunotherapy (OIT) is safe for preschoolers in real-world settings. This study found that OIT for tree nut allergies in young children is well-tolerated, similar to previous peanut OIT research.
Area of Science:
- Allergy and Immunology
- Pediatric Allergy
- Immunotherapy
Background:
- Previous research established the safety of peanut oral immunotherapy (OIT) in preschool-aged children in real-world settings.
- This study builds upon prior work by investigating a different allergen category.
Purpose of the Study:
- To evaluate the safety and tolerability of tree nut (TN) OIT in preschoolers within a real-world, multicenter environment.
- To compare the outcomes of TN-OIT with previously published peanut OIT data.
Main Methods:
- Tree nut OIT (cashew/pistachio, walnut/pecan, hazelnut, almond, macadamia) was administered to preschoolers meeting specific allergy criteria (SPT wheal ≥3 mm or IgE ≥0.35 kU/L with reaction, or IgE ≥5 kU/L without ingestion history).
- Dose escalation occurred every 2–4 weeks to a maintenance dose of 300 mg TN protein.
- Symptom severity was graded using the modified World Allergy Organization Subcutaneous Immunotherapy Reaction Grading System.
Main Results:
- Out of 92 patients starting TN-OIT, 85.9% underwent single-food OIT and 14.1% received multi-food OIT.
- The majority of patients (96.7%) reached maintenance dose, with only 4.3% discontinuing therapy.
- Most reactions (70.7%) were mild (grade 1 or 2), with no severe reactions (grade 3 or 4); 2.17% required epinephrine.
Conclusions:
- Preschool tree nut oral immunotherapy (OIT) is demonstrated to be safe and well-tolerated in a real-world, multicenter context.
- The safety profile of TN-OIT in this cohort is comparable to findings from preschool peanut OIT studies.
Background:
Our group previously described preschool peanut oral immunotherapy (OIT) in a real-world, multicenter setting, suggesting that this therapy is safe for most preschoolers.
Objective:
To examine the safety and tolerability of tree nut (TN) OIT in preschoolers in the real world.
Methods:
As part of a Canada-wide quality improvement project, TN-OIT (cashew/pistachio, walnut/pecan, hazelnut, almond, and macadamia nut) was performed in preschoolers who had (1) a skin prick test wheal diameter greater than or equal to 3 mm or a specific IgE level greater than or equal to 0.35 kU/L and a convincing objective IgE-mediated reaction or (2) no ingestion history and a specific IgE level greater than or equal to 5 kU/L. Dose escalations were performed every 2 to 4 weeks till a maintenance dose of 300 mg of TN protein was reached. Symptoms were recorded and classified using the modified World Allergy Organization Subcutaneous Immunotherapy Reaction Grading System (1, mildest; 5, fatal).
Results:
Of the 92 patients who started TN-OIT from 2018 to 2021, 79 (85.9%) underwent single-food TN-OIT and 13 (14.1%) underwent multifood TN-OIT to 2 (10.8%) or 3 (3.3%) TNs. Eighty-nine (96.7%) patients reached maintenance, and 4 (4.3%) dropped out. Sixty-five (70.7%) patients experienced reactions during buildup: 35 (38.0%) grade 1 reactions, 30 (32.6%) grade 2 reactions, no grade 3 or 4 reactions, and 2 (2.17%) received epinephrine.
Conclusions:
Preschool TN-OIT in a real-world, multicenter setting appears safe and tolerable, with results comparable with our previously reported peanut OIT findings.
