Predictive factors of allergy to pistachio in children allergic to cashew nut

Abstract

Background: Cashew nut (CN) allergy prevalence has increased over the last few years. In children allergic to CN, complete avoidance of pistachio is usually recommended, but recent study showed that only one third of children allergic to CN were also allergic to pistachio. The aim of our study was to identify predictive factors of allergy to pistachio in children allergic to CN. Methods: All children who had a positive oral food challenge (OFC) to CN between November 2013 and October 2017 in the Paediatric Allergy Department of the University Hospital of Nancy were included. Logistic regression models were used to predict the probability of allergy to pistachio.Results: Among the 147 children included, tolerance or allergy to pistachio was known for 51. Out of these, 40 were allergic to pistachio (78.4%). Children allergic to pistachio had a larger weal size of skin prick test to CN (P = .01) and pistachio (P = .0007) and a lower reaction dose to CN (P < .0001). In multivariate analysis, only the reaction dose to CN was significantly associated with allergy to pistachio.Children with a low reaction dose to CN were significantly more at risk to have an allergy to pistachio (P = .01). Conclusion:A low reaction dose to CN seems to be a predictive factor of allergy to pistachio in children allergic to CN. In order to limit unnecessary food eviction, a pistachio OFC should be performed in children having high reaction dose whatever the importance of the skin or the specific IgE sensitization to pistachio. K E Y W O R D S allergy, cashew nut, children, pistachio, threshold dose, tree nut 1 | INTRODUC TI ON Cashew nut (CN) allergy prevalence has increased in the last few years. In a recent study on 1045 positive oral food challenges (OFCs), CN was the second most common allergen, after peanut. 1 In the SchoolNuts study, CN allergy was the most frequent tree nut (TN) allergy. 2 CN can cause immediate anaphylactic reaction even more severe than peanut. 3,4 CN allergy, along with other TN allergies, appears around the age of two, when CN and pistachio are introduced into the child's diet. 5 | 507 SABA et Al.CN and pistachio belong to the same botanical family called the anacardiaceae 6 ; therefore, the avoidance of pistachio is also currently recommended in case of allergy to CN. Avoidance of TN is becoming more and more difficult to realize. The presence of CN and pistachio in very low doses is difficult to eliminate, due to cross-contamination in food lines. 7 Moreover, the consumption of CN and pistachio has increased in the past few years due to the changes in food habits, and they are now used in products such as snacks, butters, pesto, bakery, and confectionary items. 8In vitro reactivity between CN and pistachio has been established by specific IgE (sIgE) inhibition tests. 9 Willison et al 10 demonstrated that Ana o 1 (specific CN protein) and Pis v 3 (specific pistachio protein) had large structural homologies. Moreover, Uotila et al 11 reported that pistachio and CN had one of the strongest co-sensitization linkag...

IgE-Binding Epitopes of Pis v 1, Pis v 2 and Pis v 3, the Pistachio (Pistacia vera) Seed Allergens

“…In this respect, the sequence similarities observed between the homologous allergens of Anacardiaceae, e.g., between Pis v 1 and Ana o 3 or between Pis v 2 and Ana o 2, account for the high level of cross-reactivity and cross-allergenicity observed between pistachio and cashew. The IgE-binding cross-reactivity the major allergens from pistachio, Pis v 1, Pis v 2 and Pis v 3, share with homologous proteins from peanut, tree nuts and proteins from, sesame, buckwheat, peppercorn or mango, has a clinical incidence and in particular, helps to discriminate between allergies and co-sensitizations [19,22,[70][71][72][73][74][75][76][77][78]. Whereas co-sensitization frequently occurs between pistachio and cashew, it is clinically relevant in only one-third of cases [72].…”

“…Whereas co-sensitization frequently occurs between pistachio and cashew, it is clinically relevant in only one-third of cases [72]. However, skin prick tests (SPT) performed on French children indicated that a low reaction dose to cashew in cashew-allergic children would be a predictive factor of allergy to pistachio [78]. Accordingly, oral food challenge to pistachio should be avoided in cashew-allergic children exhibiting a low reaction dose to cashew nut.…”

Peanut Can Be Used as a Reference Allergen for Hazard Characterization in Food Allergen Risk Management: A Rapid Evidence Assessment and Meta-Analysis

“…Finally, we assessed the rate of anaphylaxis to very low (≤upper 95th CI for the ED 05 ) 6 levels of allergen consumption at FC to cashew 27 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ( Table E1 , available in this article’s Online Repository at www.jaci-inpractice.org ), hazelnut 27 , 28 , 29 , 30 , 31 , 37 , 38 , 39 , 40 ( Table E2 , available in this article’s Online Repository at www.jaci-inpractice.org ), and walnut 29 , 30 , 41 , 42 , 43 ( Table E3 , available in this article’s Online Repository at www.jaci-inpractice.org ) reported in the literature, and undertook a meta-analysis ( Figures E1-E3 , available in this article’s Online Repository at www.jaci-inpractice.org ). These data are summarized in Table IV .…”

Should cashew and pistachio be clinically considered as one allergen?

“…Thus, the fear for a life-threatening allergic reaction after accidental exposure to an allergen has a significant impact on the quality of life of both patients and their families 1,3 . Among tree nuts, the prevalence of cashew allergy is increasing, being reported to cause even more severe anaphylactic reactions than peanut allergy 1,4 . Cashew (CN) and pistachio share a phylogenetic origin and are members of the Anacardiaceae family.…”