Background The sting challenge test (SCT) is regarded as the most reliable method for assessing the effectiveness of venom immunotherapy (VIT). However, its predictive value in patients undergoing VIT is still unclear. This study aims to evaluate the predictive value of the SCT. Methods A multicenter retrospective observational study was conducted on patients receiving VIT who underwent SCT. The study gathered data on patient demographics, diagnosis, immunotherapy details, outcomes of the SCT and their comparison to subsequent field sting (FS) results. Results A total of 261 patients were included, and 372 SCT were recorded. The majority of the patients (75.1%) were men. A diagnosis of mastocytosis was confirmed in 7.7%. The final diagnoses were allergy to Apis mellifera (48.7%), Polistes dominula (36.8%), Vespula spp. (2.7%) and Polistes dominula plus Vespula spp. (10,7%). Sting challenge tests were performed with Apis in 61.6% of the overall tests, Polistes in 34.1% and Vespula in 4.3%. The majority (95.7%) of the SCT were negative. Regarding FS, 146 patients (56.2%) experienced 306 FS of which 95.1% were negative. Among these 146 patients, 137 had a negative SCT, and 130 of these also had a subsequent negative FS, resulting in a 94.9% of negative predictive value (NPV) of the test. Of the patients who experienced FS, 9 had a positive SCT and only 3 of them had a positive FS, resulting in a positive predictive value of 33,3%. Conclusions SCT is a safe procedure, and its high NPV emphasizes the usefulness of this test in assessing the effectiveness of VIT.

Background: We believe there is a profile of patient with eosinophilic oesophagitis and atopic background, marked by the existence of IgE-mediated sensitizations to environmental and food allergens. We suspect that the prevalence of sensitization to panallergens will be high and this will probably be relevant in terms of the onset and clinical course of the disease. Our aim is to report the observed sensitivities to environmental and food allergens in patients with eosinophilic oesophagitis with atopic background as well as characterizing other markers or analytical parameters in these patients. Methods: We collated clinical and analytical data from 160 adult patients with a reported diagnosis of eosinophilic oesophagitis. These patients were studied between 1 January 2012 and 31 December 2020. During an initial visit skin tests were performed with full batteries of routine aero-allergens and foodstuffs. Patients were subsequently referred for blood test and determination of CAP, blood count and total IgE (in all cases), as well as eosinophilic cation protein and IMMUNOISAC in the centres in which this was available. Results: We were able to detect a broad spectrum of sensitizations to environmental, foodstuffs and panallergens. The most common allergic disease was rhinoconjuntivitis. The sensitizations observed to foodstuffs were atypical for the adult population and were not responsible for manifestations compatible with immediate allergy. An important percentage of patients presented seasonal worsening of choking symptoms. Conclusions: We should be able to identify patients with eosinophilic oesophagitis and atopic background. Identifying this phenomenon would enable giving dietary and environmental recommendations as well as more specific and effective treatments to our patients.