Peanut sensitization in a group of allergic Egyptian children (original) (raw)

Sensitization profiles to peanut allergens in Belgium; cracking the code in infants, children and adults

Acta Clinica Belgica, 2016

Peanut allergy shows distinct clinical patterns that can be predicted by component resolved diagnosis. However data about peanut sensitization profiles in populations with a broad agestratification are scarce. Methods Sera of 89 peanut allergic patients (age 1-70 years), 21 infants (< 1y) with atopic dermatitis (AD) sensitized to peanut, 24 age matched peanut tolerant individuals with positive sIgE to peanut and 15 healthy individuals were tested for sIgE reactivity to rAra h 1, rAra h 2, rAra h 3, rAra h 8, rAra h 9 and rBet v 1 (FEIA ImmunoCAP, Thermo Fisher Scientific). Results In infants with AD, Ara h 1, Ara h 2 and Ara h 3 enabled to explain 14/21 (67%) of peanut sensitizations. No sensitization to Ara h 8 or Bet v 1 was observed. Patients with generalized reactions were more frequently sensitized to Ara h 1, Ara h 2 and Ara h 3 compared to patients with an oral allergy syndrome (OAS) and peanut tolerant patients. Sensitization to Ara h 8 was significantly more observed in patients with an OAS. Ara h 2 showed to be the best marker to distinguish patients with generalized reactions from patients with an OAS and/or peanut sensitized patients but tolerating the legume. Conclusion Faber et al., 4 Sensitization to Ara h 1, Ara h 2 and Ara h 3 can have early onset and is predominantly associated with a more severe outcome. Ara h 2 is the best marker of a generalized peanut allergy.

Risk Factors for Anaphylaxis in Children Allergic to Peanuts

Background and Objectives: Peanut allergy is the most common single cause of anaphylaxis in children. The risk factors for anaphylaxis in children with peanut allergy are not well defined. Therefore, we aimed to identify epidemiological, clinical and laboratory characteristics of children with peanut allergy that may predict the severity of allergic reaction and anaphylaxis. Materials and Methods: We conducted a cross-sectional study and included 94 children with peanut allergy. Allergy testing was performed, including skin prick testing and determination of specific IgE levels to peanut and its Ara h2 component. In case of discordance between patient history and allergy testing, an oral food challenge with peanut was performed. Results: Anaphylaxis, moderate and mild reactions to peanuts occurred in 33 (35.1%), 30 (31.9%) and 31 (33.0%) patients, respectively. The severity of the allergic reaction only weakly correlated (p = 0.04) with the amount of peanuts consumed. The median num...

Rising prevalence of allergy to peanut in children: Data from 2 sequential cohorts

Journal of Allergy and Clinical Immunology, 2002

Background: Allergy to peanut is common. However, it is not known whether the prevalence of sensitization and clinical allergy to peanut is increasing. Objective: We sought to determine any change in the prevalence of peanut sensitization and reactivity in early childhood in 2 sequential cohorts in the same geographic area 6 years apart. Methods: Of 2878 children born between September 1, 1994, and August 31, 1996, living on the Isle of Wight, 1273 completed questionnaires, and 1246 had skin prick tests at the age of 3 to 4 years. Those with positive skin prick test responses to peanut were subjected to oral peanut challenges, unless there was a history of immediate systemic reaction. These data were compared with information on sensitization and clinical allergy to peanut available from a previous cohort born in 1989 in the same geographic area. Results: There was a 2-fold increase in reported peanut allergy (0.5% [6/1218] to 1.0% [13/1273]), but the difference was nonsignificant (P = .2). Peanut sensitization increased 3-fold, with 41 (3.3%) of 1246 children sensitized in 1994 to 1996 compared with 11 (1.1%) of 981 sensitized 6 years ago (P = .001). Of 41 sensitized children in the current study, 10 reported a convincing clinical reaction to peanut, and 8 had positive oral challenge results, giving an overall estimate of peanut allergy of 1.5% (18/1246). Conclusions: Sensitization to peanut had increased between 1989 and 1994 to 1996. There was a strong but statistically nonsignificant trend for increase in reported peanut allergy. (J Allergy Clin Immunol 2002;110:784-9.)

Environmental peanut exposure increases the risk of peanut sensitization in high risk children

Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology, 2018

High household peanut consumption is associated with the development of peanut allergy, especially when peanut allergic cases are compared against atopic controls; thus environmental peanut exposure (EPE) may be a risk factor for peanut sensitization and allergy. In this study we explored the relationship between EPE and school-age peanut sensitization in a population based cohort. Maternal bed-dust was collected postnatally and EPE was quantified using a polyclonal peanut ELISA. Peanut sensitization was assessed by specific IgE to peanut extract and sIgE to peanut protein component allergens Ara h 1, 2 or 3 ≥0.35kU/L (primary peanut sensitization). Initial nested case control analysis was performed comparing peanut sensitized cases against high-risk controls (matched for parental atopy) (n=411) using a conditional regression analysis. This was followed by whole cohort analysis (n=1878) comparing EPE against peanut sIgE sensitization at ages 4 and 8 years using Generalized Estimatin...

Allergy or tolerance in children sensitized to peanut: Prevalence and differentiation using component-resolved diagnostics

Journal of Allergy and Clinical Immunology, 2010

Background: Not all peanut-sensitized children develop allergic reactions on exposure. Objective: To establish by oral food challenge the proportion of children with clinical peanut allergy among those considered peanut-sensitized by using skin prick tests and/or IgE measurement, and to investigate whether component-resolved diagnostics using microarray could differentiate peanut allergy from tolerance. Methods: Within a population-based birth cohort, we ascertained peanut sensitization by skin tests and IgE measurement at age 8 years. Among sensitized children, we determined peanut allergy versus tolerance by oral food challenges. We used open challenge among children consuming peanuts (n 5 45); others underwent double-blind placebocontrolled challenge (n 5 34). We compared sensitization profiles between children with peanut allergy and peanuttolerant children by using a microarray with 12 pure components (major peanut and potentially cross-reactive components, including grass allergens). Results: Of 933 children, 110 (11.8%) were peanut-sensitized. Nineteen were not challenged (17 no consent). Twelve with a convincing history of reactions on exposure, IgE 15kUA/Land/orskintest15 kUA/L and/or skin test 15kUA/Land/orskintest8mm were considered allergic without challenge. Of the remaining 79 children who underwent challenge, 7 had $2 objective signs and were designated as having peanut allergy. We estimated the prevalence of clinical peanut allergy among sensitized subjects as 22.4% (95% CI, 14.8% to 32.3%). By using component-resolved diagnostics, we detected marked differences in the pattern of component recognition between children with peanut allergy (n 5 29; group enriched with 12 children with allergy) and peanuttolerant children (n 5 52). The peanut component Ara h 2 was the most important predictor of clinical allergy. Conclusion: The majority of children considered peanutsensitized on the basis of standard tests do not have peanut allergy. Component-resolved diagnostics may facilitate the diagnosis of peanut allergy. (J Allergy Clin Immunol 2010;125:191-7.)

Diagnosis of Peanut Allergy in Preschool Children: The Impact of Skin Testing With a Novel Composition of Peanuts

Frontiers in Pediatrics, 2021

Peanut allergy is an increasing concern in younger children. Available bedside diagnostic tools, i.e., prick tests with commercial extracts or peanut-containing foods have only limited predictive values. In a cohort of preschoolers with both a history of allergic reactions and sensitization to peanut proteins, we aimed to characterize the impact of skin tests with a novel composition of peanuts LPP-MH. Almost one quarter (27/110) of preschool children, with a history of allergic reactions to peanuts and positive standard IgE-mediated tests for peanut allergy, can tolerate the reintroduction of peanut proteins into their diet after resolving their allergy and, thus, can avoid adverse health outcomes associated with the false diagnosis. In the younger age group, a quarter of peanut allergic children, display a relatively high threshold, potentially enabling an easier and safer oral immunotherapy protocol in this window of opportunity in childhood. The use of the novel diagnostic skin ...

Peanut allergy: Clinical and immunologic differences among patients from 3 different geographic regions

Journal of Allergy and Clinical Immunology, 2011

Background: Peanut allergy affects persons from various geographic regions where populations are exposed to different dietary habits and environmental pollens. Objective: We sought to describe the clinical and immunologic characteristics of patients with peanut allergy from 3 countries (Spain, the United States, and Sweden) using a molecular component diagnostic approach. Methods: Patients with peanut allergy from Madrid (Spain, n 5 50), New York (United States, n 5 30), Gothenburg, and Stockholm (both Sweden, n 5 35) were enrolled. Clinical data were obtained either from a specific questionnaire or gathered from chart reviews. IgE antibodies to peanut extract and the peanut allergens rAra h 1, 2, 3, 8 and 9, as well as to cross-reactive birch (rBet v 1) and grass (rPhl p 1, 5, 7, and 12) pollen allergens, were analyzed. Results: American patients frequently had IgE antibodies to rAra h 1 to 3 (56.7% to 90.0%) and often presented with severe symptoms. Spanish patients recognized these 3 recombinant peanut allergens less frequently (16.0% to 42.0%), were more often sensitized to the lipid transfer protein rAra h 9 (60.0%), and typically had peanut allergy after becoming allergic to other plant-derived foods. Swedish patients detected rAra h 1 to 3 more frequently than Spanish patients (37.1% to 74.3%) and had the highest sensitization rate to the Bet v 1 homologue rAra h 8 (65.7%), as well as to rBet v 1 (82.9%). Spanish and Swedish patients became allergic to peanut at 2 years or later, whereas the American children became allergic around 1 year of age. Conclusions: Peanut allergy has different clinical and immunologic patterns in different areas of the world. Allergen component diagnostics might help us to better understand this complex entity.