Aim and scopePediatric Allergy and Immunology publishes original contributions and comprehensive reviews related to the understanding and treatment of immune defi ciency, allergic infl ammatory and infectious diseases in children. Other areas of interest include development of specifi c and accessory immunity, and the immunological interaction during pregnancy and lactation between mother and child. As the journal is intended to promote communication between scientists engaged in basic research and clinicians working with children, both clinical and experimental work will be published.

Background There is controversy whether taking β‐blockers or ACE inhibitors (ACEI) is a risk factor for more severe systemic insect sting reactions (SSR) and whether it increases the number or severity of adverse events (AE) during venom immunotherapy (VIT). Methods In this open, prospective, observational, multicenter trial, we recruited patients with a history of a SSR and indication for VIT. The primary objective of this study was to evaluate whether patients taking β‐blockers or ACEI show more systemic AE during VIT compared to patients without such treatment. Results In total, 1,425 patients were enrolled and VIT was performed in 1,342 patients. Of all patients included, 388 (27.2%) took antihypertensive (AHT) drugs (10.4% took β‐blockers, 11.9% ACEI, 5.0% β‐blockers and ACEI). Only 5.6% of patients under AHT treatment experienced systemic AE during VIT as compared with 7.4% of patients without these drugs (OR: 0.74, 95% CI: 0.43–1.22, p = 0.25). The severity of the initial sting reaction was not affected by the intake of β‐blockers or ACEI (OR: 1.14, 95% CI: 0.89–1.46, p = 0.29). In total, 210 (17.7%) patients were re‐stung during VIT and 191 (91.0%) tolerated the sting without systemic symptoms. Of the 19 patients with VIT treatment failure, 4 took β‐blockers, none an ACEI. Conclusions This trial provides robust evidence that taking β‐blockers or ACEI does neither increase the frequency of systemic AE during VIT nor aggravate SSR. Moreover, results suggest that these drugs do not impair effectiveness of VIT. (Funded by Medical University of Graz, Austria; Clinicaltrials.gov number, NCT04269629).

Diagnosis of Hymenoptera venom allergy (HVA) is straightforward in the majority of patients, but can be challenging in double positive and test negative patients. Test results sometimes can be confusing as patients with high skin test reactivity and high specific IgE (sIgE) levels are not at risk for severe systemic sting reactions (SSR), and conversely, patients with weakly positive or even negative tests can experience severe SSR. Venom immunotherapy (VIT) is safe, highly effective, and recommended in patients with moderate to severe SSR and in patients with SSR confined to generalized skin symptoms if quality of life is impaired.

| 2091 LETTERS TO THE EDITOR both IL-33 and IgE together with oral allergen immunotherapy may facilitate the development of sustained tolerance by removing both pathways of mast cell-mediated suppression of Treg generation.

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