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This article discusses the variability in allergen repertoire among commercial shellfish skin prick test (SPT) extracts. The study found that widely used commercial SPT extracts for shellfish allergy diagnosis are generally not standardized, limiting the diagnostic value of the results. The researchers analyzed 11 commercial crustacean and five mollusc SPT extracts and found significant variability in protein content and allergen repertoire. The study concludes that standardization of allergen extracts is urgently needed to improve the accuracy and reliability of SPT for shellfish allergy diagnosis. [Extracted from the article]

Background: Clinical management of shrimp allergy is hampered by the lack of accurate tests. Molecular diagnosis has been shown to more accurately reflect the clinical reactivity but the full spectrum of shrimp allergens and their clinical relevance are yet to be established. We therefore sought to comprehend the allergen repertoire of shrimp, investigate and compare the sensitization pattern and diagnostic value of the allergens in allergic subjects of two distinct populations. Methods: Sera were collected from 85 subjects with challenge‐proven or doctor‐diagnosed shrimp allergy in Hong Kong and Thailand. The IgE‐binding proteins of Penaeus monodon were probed by Western blotting and identified by mass spectrometry. Recombinant shrimp allergens were synthesized and analyzed for IgE sensitization by ELISA. Results: Ten IgE‐binding proteins were identified, and a comprehensive panel of 11 recombinant shrimp allergens was generated. The major shrimp allergens among Hong Kong subjects were troponin C (Pen m 6) and glycogen phosphorylase (Pen m 14, 47.1%), tropomyosin (Pen m 1, 41.2%) and sarcoplasmic‐calcium binding protein (Pen m 4, 35.3%), while those among Thai subjects were Pen m 1 (68.8%), Pen m 6 (50.0%) and fatty acid‐binding protein (Pen m 13, 37.5%). Component‐based tests yielded significantly higher area under curve values (0.77–0.96) than shrimp extract‐IgE test (0.70–0.75). Yet the best component test differed between populations; Pen m 1‐IgE test added diagnostic value only in the Thai cohort, whereas sensitizations to other components were better predictors of shrimp allergy in Hong Kong patients. Conclusion: Pen m 14 was identified as a novel shrimp allergen predictive of challenge outcome. Molecular diagnosis better predicts shrimp allergy than conventional tests, but the relevant component is population dependent. [ABSTRACT FROM AUTHOR]

Anaphylaxis, desensitization, food allergen, food allergy, omalizumab, oral immunotherapy, shellfish allergy, shrimp allergy, sustained unresponsiveness In addition, commercial shrimp extracts are heterogeneous with variable allergen representation.11 The differing allergens may result in varied responses in SPT and IgE results, which may explain Patient B's apparent negative shrimp IgE test. Keywords: anaphylaxis; desensitization; food allergen; food allergy; omalizumab; oral immunotherapy; shellfish allergy; shrimp allergy; sustained unresponsiveness EN anaphylaxis desensitization food allergen food allergy omalizumab oral immunotherapy shellfish allergy shrimp allergy sustained unresponsiveness 1 4 4 01/05/22 20220101 NES 220101 AUTHOR CONTRIBUTIONS B Diem-Tran Nguyen: b Data curation (equal); Investigation (equal); Project administration (lead); Visualization (lead); Writing-original draft (lead); Writing-review & editing (equal). [Extracted from the article]

Food allergies affect approximately 3.5–4.0% of the world’s population and can range from a mere inconvenience to a life-threatening condition. Over 90% of food allergies in childhood are caused by eight foods: cow’s milk, hen’s egg, soy, peanuts, tree nuts, wheat, fish, and shellfish. Shellfish allergy is known to be common and persistent in adults, and is an important cause of food induced anaphylaxis around the world for both children and adults. Most shellfish-allergic children have sensitivity to dust mite and cockroach allergens. Diagnostic cut-off levels for skin prick testing in children with shrimp allergy exist but there are no diagnostic serum-specific immunoglobulin E (IgE) values. All patients with symptoms of IgE-mediated reactions to shellfish should receive epinephrine autoinjectors, even if the initial symptoms are mild. In this study, we review three cases of clinical presentations of shellfish allergy in children. [ABSTRACT FROM AUTHOR]

Background Food allergy seems to be increasing in Asia as well as world-wide. Our aim was to characterize food protein sensitization patterns in a population of Asian children with possible food allergy. Methods Children presenting to our allergy clinic over 3 years with symptomatic allergic disease and at least one specific food allergen sensitization documented on skin prick testing were included in the analysis. Results Two hundred and twenty-seven patients fulfilled inclusion criteria. Ninety (40%) of the positive skin tests were positive to egg, 87 (39%) to shellfish, 62 (27.3%) to peanut, 30 (13.2%) to fish, 27 (11.8%) to cow's milk, 21 (9.3%) to sesame, 13 (3.7%) to wheat and eight (3.2%) to soy. Peanut sensitization was the third most common sensitizing allergen, and seen mostly in young atopic children with multiple food hypersensitivities and a family history of atopic dermatitis. The median reported age of first exposure to fish and shellfish was 6 and 12 months, respectively. The mean age at presentation of children with shellfish hypersensitivity was at 6.7 years of age. The likelihood of shellfish sensitization was increased in children with concomitant sensitization to cockroaches. Conclusions In contrast to previously reported low peanut allergy rates in Asia, in our review, peanut sensitization is present in 27% (62/227) of food-allergic children, mostly in patients with multiple food protein sensitizations. Temporal patterns of first exposure of infants to fish and shellfish are unique to the Asian diet. Shellfish are a major sensitizing food source in Asian children, especially in allergic rhinitis patients sensitized to cockroaches. [ABSTRACT FROM AUTHOR]