Individuals with a history of allergy are potentially at risk of suffering from adverse effects after COVID-19 vaccination. We sought to assess the tolerance towards the Pfizer-BioNTech vaccine in allergic patients. To address this issue, we used a questionnaire conducted on-line in a group of medical professionals who were vaccinated with the Pfizer-BioNTech vaccine. A total of 1808 respondents, out of whom 1707 received two doses of the vaccine, returned the questionnaire. Local reactions after injection were more frequent in allergic individuals after both doses (swelling p = 0.0003). Systemic adverse events (AE-SYS) occurred more often after the second than the first dose in both groups (allergic persons: 77.29% vs. 41.06%); vomiting and arthralgia occurred more often in allergic subjects (p = 0.0009). AE-SYS in allergic individuals lasted longer than in non-allergic ones after the first (p = 0.01) and the second dose (p = 0.0009). Allergic reactions after vaccination were reported more frequently in allergic subjects: after the first dose (p = 0.00001) and after the second dose (p = 0.001). Rhinitis was the most frequent symptom observed more often in allergic patients. No severe allergic reactions occurred during the full cycle of vaccination. Although the Pfizer-BioNTech vaccine is tolerated worse by allergic than non-allergic individuals, the occurring adverse symptoms are mild and do not preclude a successful completion of the vaccination cycle. The presence of symptoms suggestive of allergy does not constitute a condition of increased risk of developing clinically significant adverse events following Pfizer COVID-19 vaccination.

Mast cell (MC) mediators, among them prostaglandin D₂ (PGD₂) and 9α,11β-PGF₂, PGD₂’s metabolite, play a key role in allergic reactions, including bee venom anaphylaxis (BVA). Assessment of these mediators has never been performed in BVA. The aim of the study was to assess the activation of MC during in vivo provocation with bee venom (BV) and to measure PGD₂ and 9α,11β-PGF₂ in the course of an allergen challenge. The second aim was to determine if assessment of these mediators could be useful for predicting adverse events during venom immunotherapy (VIT). In 16 BV-VIT patients and 12 healthy subjects, levels of PGD₂ and 9α,11β-PGF₂ were assessed during BV provocation by means of the skin chamber method. Chamber fluids, collected at 5 and 15 min, were analyzed for both mediators by gas chromatography mass spectrometry negative ion chemical ionization. BVA in comparison to non-allergic patients had a significantly higher ratio of 9α,11β-PGF₂ in allergen-challenged chambers to 9α,11β-PGF₂ in allergen-free chambers after 15 min of provocation (p = 0.039). Allergen challenge resulted in a significant increase of 9α,11β-PGF₂ levels between 5 and 15 min after provocation only in BVA patients (p < 0.05). Analysis of log-transformed PGD2 levels showed significant difference between changes in PGD₂ concentration between BVA and healthy subjects. No study patient developed adverse reactions during. 9α,11β-PGF₂ is actively generated during the early allergic response to BV. Skin chamber seems to be a promising, non-invasive and safe model of in vivo allergen provocation in BV-allergic patients. High or low levels of both mediators do not predict occurrence of adverse events during VIT.

Venom immunotherapy (VIT) is the only efficient therapy for the Hymenoptera insect venom allergy. Immunotherapy with bee venom is encumbered with a higher risk of systemic side effects and/or therapeutic failures. The objective of the study was to assess if specific profiles of molecular IgE (Immunoglobulin E) responses are associated with an increased risk of systemic side effects and/or the treatment’s inefficacy. The study group numbered 64 bee venom allergic patients (BVA) who received venom immunotherapy modo ultra-rush (VIT-UR), (f/m: 32/32, mean age 43.4 ± 17.2). In total, 54.84% of them manifested allergic reactions of grades I-III (acc. to Mueller’s scale), while 48.66% manifested reactions of grade IV. In all the patients, IgE against bee venom extract, rApi m 1 and tryptase (sBT) were assessed. In 46 patients, assessments of IgE against rApi m 2, 3, 5, 10 were also performed. BVA patients manifesting cardiovascular symptoms (SYS IV⁰) showed higher levels of both sIgE-rApi m 5 (p = 0.03) and tryptase (p = 0.07) than patients with SYS I–III. Systemic adverse events during VIT with bee venom were more frequent in the induction phase than in the maintenance phase: 15.22% vs. 8.7%. In BVA patients who experienced systemic adverse events during VIT, higher concentrations of sIgE-rApi m 5 (p < 0.05), rApi m 1 (p = 0.009), and sBT (p = 0.019) were demonstrated. We conclude that higher levels of sIgE against rApi m 1, rApi m 5, and tryptase many constitute a potential marker of the severity of allergic reactions and therapeutic complications that can occur during VIT with bee venom.

Allergen immunotherapy (AIT) in patients with moderate and severe allergic symptoms to insect venom ( Hymenoptera venom allergy – HVA) significantly reduces the risk of severe reactions to subsequent sting and improves the patient’s quality of life. Allergen immunotherapy in HVA is also...