Basophil Activation Test in the Diagnosis of Anisakis Allergy: An Observational Study from an Area of High Seafood Consumption in Italy.

The rising popularity of undercooked or raw seafood containing larvae of the Anisakis parasite has led to issues of public health concern due to allergic manifestations. We conducted an observational study on the use of an innovative Anisakis allergy diagnostic algorithm in a convenience sample of 53 allergic outpatients recruited in Western Sicily, between April 2021 and March 2022. We included individuals with an anamnesis suggestive of IgE sensitization to Anisakis reporting clinical manifestation in the last month due to allergic reactions after eating fresh fish, or in subjects at high exposure risk with sea products while abstaining from fish ingestion, excluding those with documented fish sensitization. Outpatients were tested via Skin Prick Test, IgE-specific dosage and Basophil Activation Test (BAT). Twenty-six outpatients were diagnosed with Anisakis, while 27 with Chronic Urticaria (CU). We found a seven-fold excess risk for Anisakis (p4) positivity in the Anisakis allergic outpatients, as compared to the CU ones. BAT showed the best diagnostic accuracy (92.45%) and specificity (100%), while specific IgE to Ascaris (p1) documented the best sensitivity (92.31%) but a very low specificity (37.04%). In conclusion, our findings may represent a potentially useful contribution to the future development of updated clinical guidelines.

Mollusk allergy in shrimp-allergic patients: Still a complex diagnosis. An Italian real-life cross-sectional multicenter study.

Introduction: Shellfish allergy is an important cause of food allergies worldwide. Both in vivo and in vitro diagnostics failure nowadays is caused by the poor quality of the extracts associated with the scarce availability of allergenic molecules in the market. It is known that not all patients with shellfish allergies experience adverse reactions to mollusks. It is still unclear how to detect and diagnose these patients correctly. Aim: To investigate the features of shrimp-allergic patients either reactive or tolerant to mollusks, with the currently available diagnostic methods. Methods: Nineteen centers, scattered throughout Italy, participated in the real-life study, enrolling patients allergic to shrimp with or without associated reactions to mollusks. Patients underwent skin tests using commercial extracts or fresh raw and cooked shrimp and mollusks, and IgE reactivity to currently available allergenic extracts and molecules was measured in vitro. Results: Two hundred and forty-seven individuals with a self reported adverse reactions to shrimp participated in the study; of these 47.8% reported an adverse reaction to mollusks ingestion (cephalopod and/or bivalve). Neither of the tests used, in vivo nor in vitro, was able to detect all selected patients. Accordingly, a great heterogeneity of results was observed: in vivo and in vitro tests agreed in 52% and 62% of cases. Skin tests were able to identify the mollusk reactors (p < 0.001), also using fresh cooked or raw food (p < 0.001). The reactivity profile of mollusk reactors was dominated by Pen m 1, over Pen m 2 and Pen m 4 compared to tolerant subjects, but 33% of patients were not detected by any of the available molecules. Overall, a higher frequency of IgE rectivity to shrimp was recorded in northern Italy, while mollusk reactivity was more frequent in the center-south. Conclusion: The current diagnostic methods are inadequate to predict the cross-reactivity between crustaceans and mollusks. The detection of mollusks hypersensitivity should still rely on skin tests with fresh material. The exclusion of mollusks from shrimp allergic patients' diets should occur when clinical history, available diagnostic instruments, and/or tolerance tests support such a decision.

Allergy to Polyethilenglicole of Anti-SARS CoV2 Vaccine Recipient: A Case Report of Young Adult Recipient and the Management of Future Exposure to SARS-CoV2.

The main contraindication to the anti-SARS CoV2 vaccine is an anaphylactic reaction to a vaccine component. The need to vaccinate allergic people who are at higher risk can be of public health interest and this report shows a case of an allergic reaction to PEG of a HCW who had received the first dose of anti-SARS CoV2 vaccine. For 5 h after the administration of the vaccine, she had the appearance of erythematous spots on the face and neck, and a feeling of a slurred mouth and hoarseness. In order to treat the event, she was administered 8 mg intravenous dexamethasone, 1 vial intravenous chlorphenamine maleate, 250 mL intravenous 0.9% NaCl, and conventional oxygen therapy (2 L/min) with complete resolution of the suspected adverse drug reaction. According to the contraindication to the cutaneous test for this patient, BAT was used for further investigations. The patient who suffered the adverse reaction to the COVID-19 vaccine and other five allergic patients who did not report any adverse reaction after the vaccination were tested. There was a significant activation of the vaccine-reactive patient's basophils with 14.79 CD203chigh% at the concentration of 0.2 mg/mL, while other patients were negative. People who have a confirmed reaction to a vaccine component should undergo further investigation to discover other possible cross-reactions and select the right vaccine to immunize them.

The extract, the molecular allergen or both for the in vitro diagnosis of peach and peanut sensitization?

INTRODUCTION: Identifying the target molecule in food allergies, helps to assess the risk of anaphylaxis in a patient. Lipid Transfer Protein is the most frequent cause of food allergies in the Mediterranean area. The diagnosis based on allergenic extracts, suffers from a high variability in the results because some important allergenic molecules are lacking. This study was disegned to assess whether Pru p 3 and Ara h 9 molecules are quantitative and qualitative enough present in their whole allergenic extracts. METHODS: 943 patients with a clinical history of suspected peach and/or peanut food allergies were recruited and underwent measurement of a specific serum IgE (ImmunoCAP system (Thermofisher/Phadia Diagnostics, Uppsala, Sweden) to the following allergens and molecules: peach (f95) and/or peanut (f13), Pru p 3 (f420), Pru p 1 (f419), Pru p 4 (f421), Ara h 1 (f422), Ara h 2 (f423) Ara h 3 (f424) and Ara h 9 (f427). RESULTS: Out of the 943 patients included in this study, 122 were positive to sIgE to peanut extract. At a cut-off point of 0.35 kIU/L, 62 patients were positive to sIgE to Ara h 9 but negative to peanut extract. Increasing the cut-off point of Ara h 9 at 10 kIU/L, 15 patients were only positive to sIgE to Ara h 9. 244 out of the 943 patients were positive to sIgE to peach extract. At a cut-off point of 0.35 kIU/L, 27 patients were negative to sIgE to Pru p 3 and positive to sIgE to peach extract, whilst 11 patients were peach extract sIgE positive and sIgE negative to Pru p 1, Pru p 3 and Pru p 4. Only 12 patients resulted positive to Pru p1 and/or Pru p 4. CONCLUSION: Our data strongly suggests to include the measurement of sIgE to Ara h 9 into the diagnostic algorithm of peanut sensitization. 4.5% of the sicilian population suspected of peach sensitization were positive to peach extract and negative to all the available molecules.