Skin Prick Test Wheal Diameter Research Articles

Long-term safety and immunologic outcomes of daily oral immunotherapy for peanut allergy.

Oral immunotherapy containing peanut (Arachis hypogaea) allergen powder-dnfp (PTAH) (Palforzia [Aimmune Therapeutics, Brisbane, Calif]) for 9 to 12 months resulted in higher tolerated amounts of peanut protein in PTAH-treated individuals aged 4 to 17 years with peanut allergy than in placebo-treated participants. We aimed to describe additional long-term pooled safety data and changes in peanut sensitization markers from baseline through approximately 5 years of treatment. The results from 6 clinical trials of PTAH (3 controlled and 3 open-label extension studies [N= 1227]) were pooled, and analysis of safety outcomes and immunologic data was performed. The PTAH doses were administered sequentially as follows: initial dose escalation (dose increased to 6 mg over 2 days), updosing (dose increased every 2 weeks to 300 mg for a minimum of 6 months), and maintenance dosing (300 mg per day). There was a trend toward decreased adverse events (AEs) at years 1 and 2 that was maintained up to 5 years, with 94% of patients experiencing mild or moderate AEs and only 13% discontinuing PTAH use because of AEs overall. Gastrointestinal symptoms were the most commonly reported treatment-related AEs. Adownward trend in systemic allergic reactions was also reported. PTAH treatment resulted in reduced levels of peanut-specific IgE after the first year and increased levels of peanut-specific IgG4, with a lowered peanut-specific IgE:IgG4 ratio. Areduction in median peanut skin prick test wheal diameter was observed (11.50 mm at baseline vs 5.75 mm at year 5). Long-term immunomodulation without any new safety signals was reported with PTAH immunotherapy in the largest safety data set and longest treatment duration for oral immunotherapy published to date.

Real-World Safety Analysis of Preschool Tree Nut Oral Immunotherapy

Our group previously described preschool peanut oral immunotherapy (OIT) in a real-world, multicenter setting, suggesting that this therapy is safe for most preschoolers. To examine the safety and tolerability of tree nut (TN) OIT in preschoolers in the real world. As part of a Canada-wide quality improvement project, TN-OIT (cashew/pistachio, walnut/pecan, hazelnut, almond, and macadamia nut) was performed in preschoolers who had (1) a skin prick test wheal diameter greater than or equal to 3 mm or a specific IgE level greater than or equal to 0.35 kU/L and a convincing objective IgE-mediated reaction or (2) no ingestion history and a specific IgE level greater than or equal to 5 kU/L. Dose escalations were performed every 2 to 4 weeks till a maintenance dose of 300 mg of TN protein was reached. Symptoms were recorded and classified using the modified World Allergy Organization Subcutaneous Immunotherapy Reaction Grading System (1, mildest; 5, fatal). Of the 92 patients who started TN-OIT from 2018 to 2021, 79 (85.9%) underwent single-food TN-OIT and 13 (14.1%) underwent multifood TN-OIT to 2 (10.8%) or 3 (3.3%) TNs. Eighty-nine (96.7%) patients reached maintenance, and 4 (4.3%) dropped out. Sixty-five (70.7%) patients experienced reactions during buildup: 35 (38.0%) grade 1 reactions, 30 (32.6%) grade 2 reactions, no grade 3 or 4 reactions, and 2 (2.17%) received epinephrine. Preschool TN-OIT in a real-world, multicenter setting appears safe and tolerable, with results comparable with our previously reported peanut OIT findings.

The quantity of unheated milk tolerated as a predictor of tolerance to baked milk.

Tolerance of baked milk indicates a good prognosis in IgE-mediated cow's milk allergy. The present study aims to investigate the predictors of baked milk tolerance, particularly the amount of milk tolerated in the first oral food challenge (OFC) test, in children with IgE-mediated cow's milk allergy. The study included 35 cases who were diagnosed with IgE-mediated cow's milk allergy upon open OFC testing in the Pediatric Allergy Clinic. Four weeks after the diagnosis, skin prick test (SPT) and OFC were performed with baked milk. Cases who did and did not develop reactions during OFC with baked milk were compared regarding clinical and laboratory parameters. Twelve cases (33.3%) did not develop a reaction during OFC with baked milk. Those who had low levels of casein sIgE, β-lactoglobulin sIgE, and β-lactoalbumin sIgE; small SPT wheal diameter for baked milk and β-lactoalbumin; and a large amount of unheated milk tolerated in the first OFC were found to be tolerant to baked milk (p < 0.05). For predicting baked milk tolerance, a cut-off level of the amount of unheated milk tolerated in OFC was calculated as 620 mg [with the area under the curve (AUC) 0.88 (95% confidence interval 0.77-0.99) in ROC curve analysis]. If a child with cow's milk allergy is able to tolerate more than 620 mg of milk protein during challenge with unheated milk, this may show that this child will tolerate baked milk, meaning that the child will be able to tolerate cow's milk in the future.

Impaired skin barrier and allergic sensitization in early infancy.

Factors predicting allergic sensitization in the first 6months of life are poorly understood. We aimed to determine whether eczema, dry skin, and high transepidermal water loss (TEWL) at 3months were associated with allergic sensitization at 6months of age and, secondarily, to establish whether these characteristics predicted sensitization from 3 to 6months of age. At 3months of age, 1,994 infants from the population-based PreventADALL birth cohort in Norway and Sweden were assessed for eczema and dry skin on the cheeks and/or extensors; impaired skin barrier function, defined as TEWL in the upper quartile (>9.4g/m2 /h), and allergen-specific IgE levels <0.1kUA /L, available in 830. At 6months, we assessed allergic sensitization to any food (egg, cow's milk, peanut, wheat, soy) or inhalant (birch, timothy grass, dog, and cat) allergen by a skin prick test wheal diameter ≥2mm larger than negative control. Any sensitization was found in 198 of the 1,994 infants (9.9%), the majority to food allergens (n=177, 8.9%). Eczema, dry skin, and high TEWL at 3months increased the risk of sensitization at 6months; adjusted odds ratios 4.20 (95% CI 2.93-6.04), 2.09 (95% CI 1.51-2.90) and 3.67 (95% CI 2.58-5.22), respectively. Eczema predicted sensitization with 55.6% sensitivity and 68.1% specificity; dry skin with 65.3% sensitivity and 57.3% specificity; and high TEWL with 61.7% sensitivity and 78.1% specificity. Eczema, dry skin, and high TEWL at 3months predicted allergic sensitization at 6months of age.

Oral Immunotherapy for Hazelnut Allergy: A Single-Center Retrospective Study on 100 Patients

Oral immunotherapy (OIT) protects patients with IgE-mediated food allergies from food-induced allergic reactions due to accidental exposure and may improve their quality of life. This approach has never been evaluated for hazelnut, a major cause of food allergy in Europe. To determine the proportion of hazelnut-desensitized patients after 6 months of OIT and to identify predictors of successful desensitization. In a retrospective single-center study, we included patients younger than 18 years who underwent at least 6 months of hazelnut OIT for IgE-mediated allergy, defined by history of hypersensitivity reaction after hazelnut ingestion, positive hazelnut skin prick test result or specific IgE, and positive double-blind, placebo-controlled food challenge. Patients able to tolerate 1635 mg of hazelnut protein (∼8 hazelnuts) were considered to be hazelnut desensitized. We determined the proportion of desensitized patients after 6 months of OIT, searched for associations between baseline variables and successful desensitization, and estimated the frequency and severity of OIT-related adverse reactions. One hundred patients were included (64% males; median age, 5 years). History of severe reactions was noted in 7% of cases. At 6 months, the proportion of desensitized patients was 34% (95% CI, 25-44). The median eliciting dose (defined as the amount of hazelnut protein provoking a hypersensitivity reaction during the double-blind, placebo-controlled food challenge) increased from 106 mg (interquartile range, 51-249) at baseline to 523 mg (interquartile range, 190-1635) after 6 months of OIT (P < .0001). With longer therapy, the proportion of desensitized patients increased. Using multivariate analysis, successful desensitization was associated with older age (odds ratio [OR], 1.5; 95% CI, 1.2-2.2), smaller hazelnut skin prick test wheal diameter (OR, 0.61; 95% CI, 0.4-0.8), lower hazelnut specific IgE level (OR, 0.86; 95% CI, 0.72-0.98), and absence of cashew allergy (OR, 0.42; 95% CI, 0.12-0.64). Adverse reactions occurred in 30% of patients; none were severe. In a cohort of 100 patients aged 3 to 9 years, our results show for the first time that hazelnut OIT is associated with hazelnut desensitization and may be safe in most patients undergoing this therapy.

First Real-World Safety Analysis of Preschool Peanut Oral Immunotherapy

In 2017, a clinical trial of 37 subjects demonstrated that preschool peanut oral immunotherapy (P-OIT) was safe, with predominantly mild symptoms reported and only 1 moderate reaction requiring epinephrine. We sought to examine whether these findings would be applicable in a real-world setting. As part of a Canada-wide quality improvement project, community and academic allergists administered P-OIT to preschool-age children who had (1) skin prick test wheal diameter greater than or equal to 3 mm or specific IgE level greater than or equal to 0.35 kU/L and history of reaction and/or positive baseline oral food challenge, or (2) no ingestion history and specific IgE level greater than or equal to 5 kU/L. Over 16 to 22 weeks, patients had biweekly clinic visits for updosing, and consumed the dose daily at home between visits. Target maintenance dose was 300 mg peanut protein. Symptoms were classified using a modified World Allergy Organization Subcutaneous Immunotherapy Reaction Grading System (1 mildest, 5 fatal). Of 270 patients who started P-OIT in the period 2017 to 2018, 243 reached maintenance, and 27 dropped out (10.0%); 67.8% of patients experienced reactions during buildup: 36.3% grade 1, 31.1% grade 2, and 0.40% grade 4. Eleven patients (4.10%) received epinephrine (10 patients received 1 dose, 1 patient received epinephrine on 2 separate days), representing 2.23% of reactions (12 of 538) and 0.029% of doses (12 of 41,020). We are the first group to describe preschool P-OIT in a real-world multicenter setting. The treatment appears to be safe for the vast majority of patients because symptoms were generally mild and very few reactions received epinephrine; however, life-threatening reactions in a minority of patients (0.4%) can still occur.

Analysis of Oral Food Challenge Outcomes in IgE-Mediated Food Allergies to Almond in a Large Cohort

Although almond specific IgE-mediated food allergies have traditionally been equated with other tree nut allergies, outcomes of oral food challenges to almond and the utility of clinical testing to predict IgE-mediated almond hypersensitivity are not well known. To describe almond oral challenge outcomes and assess the predictive value of clinical testing. A total of 603 almond challenges performed for 590 patients, aged 1 to 66 years, were analyzed from Massachusetts General Hospital allergy practices. Reactions were graded using the Niggemann and Beyer allergic reaction grading system and the Sampson 2006 National Institute of Allergy and Infectious Diseases anaphylaxis definition. Almond challenges included 545 passes (92%), 15 (3%) indeterminates, and 30 (5%) failures, in contrast with 31% challenge failures for other foods. Most reactions were mild; 21 (4%) had grade 2/3 allergic symptoms, and 3 (0.5%) had anaphylaxis. Median almond specific IgE level was 0.89 kU/L (range, <0.35 to >100 kU/L), median skin prick test wheal diameter was 4.0 mm (range, 0-28 mm), and 475 subjects (81%) were sensitized to almond. Failure was associated with higher almond specific IgE level (P < .001), larger almond skin prick test wheal diameter (P= .001), higher peanut IgE level (P= .003), and a history of almond reaction (P < .029). Almond specific IgE level, almond skin prick test wheal diameter, and age at challenge combined demonstrated good predictive value for grade 2/3 allergic reactions by receiver-operating characteristic analysis (area under the curve, 0.83). The proportion of failed almond challenges (5%) was low in contrast with other allergens, suggesting that some almond challenges may be safely conducted with higher patient-to-staff ratios or potentially introduced at home. Although reactions are usually uncommon and mild, anaphylaxis is possible with high almond sensitization.

Immunothérapie par voie orale : modalités suivant le phénotype d’allergie alimentaire

Food allergies are a heterogeneous group of diseases for which the allergist can identify different phenotypes and offer personalised treatment. The skin prick test wheal diameter, analysis of specific IgE against classic proteins and newly identified epitopes and the eliciting dose during the induction phase enable prediction of the success of immunotherapy, but it also allowing identification of patients at higher risk of treatment failure or adverse events. Asthmatic patients and teenagers are phenotypes requiring close supervision. Phenotype studies can also help to establish the maintenance dose and the length of immunotherapy by predicting a state of sustained unresponsiveness.

Skin prick test is more useful than specific IgE for diagnosis of buckwheat allergy: A retrospective cross-sectional study

BackgroundBuckwheat (BW) is a potentially life-threatening allergen. Usefulness of BW-specific immunoglobulin-E (BW-sIgE) level for diagnosis of BW allergy is controversial, while the skin prick test (SPT) is widely used because of its less invasive procedure and immediate results. However, there are no data comparing usefulness of the SPT and BW-sIgE level. Therefore, our study aimed to clarify efficacy of the SPT for diagnosis of BW allergy. MethodsThis retrospective cross-sectional study evaluated patients who underwent an oral food challenge (OFC) for diagnosis or confirmation of acquired tolerance using 3072 mg of BW protein between July 2006 and April 2014. We then compared the diagnostic performance of BW sIgE and SPT to predict positive OFC results. ResultsWe analyzed 126 patients aged 2–16 years (median, 7.7 years), 18 (14%) of whom showed positive OFC results. Between patients with positive and negative OFC results, there was no significant difference in BW-sIgE level. However, patients with positive OFC results had a larger SPT wheal diameter. Area under the curve for positive OFC results for BW-sIgE level and SPT wheal diameter were 0.583 and 0.791, respectively. The 5%, 10%, 50%, and 90% positive predictive values of SPT wheal diameter were 2.0 mm, 5.2 mm, 14.7 mm, and 24.1 mm, respectively. ConclusionsOur study revealed that the SPT was more useful than BW-sIgE level for diagnosis of BW allergy. Thus, an OFC may be avoided if the patient's SPT wheal diameter is at least 24.1 mm.

What makes children outgrow food allergy?

What makes children outgrow food allergy?

Modified peanut oral immunotherapy protocol safely and effectively induces desensitization

Modified peanut oral immunotherapy protocol safely and effectively induces desensitization

Relationship of IgE to basophil phenotypes in peanut-sensitized adults

Relationship of IgE to basophil phenotypes in peanut-sensitized adults

Dietary baked egg accelerates resolution of egg allergy in children

Baked egg is tolerated by a majority of egg-allergic children. To characterize immunologic changes associated with ingestion of baked egg and evaluate the role that baked egg diets play in the development of tolerance to regular egg. Egg-allergic subjects who tolerated baked egg challenge incorporated baked egg into their diet. Immunologic parameters were measured at follow-up visits. A comparison group strictly avoiding egg was used to evaluate the natural history of the development of tolerance. Of the 79 subjects in the intent-to-treat group followed for a median of 37.8 months, 89% now tolerate baked egg and 53% now tolerate regular egg. Of 23 initially baked egg-reactive subjects, 14 (61%) subsequently tolerated baked egg and 6 (26%) now tolerate regular egg. Within the initially baked egg-reactive group, subjects with persistent reactivity to baked egg had higher median baseline egg white (EW)-specific IgE levels (13.5 kU(A)/L) than those who subsequently tolerated baked egg (4.4 kU(A)/L; P= .04) and regular egg (3.1 kU(A)/L; P= .05). In subjects ingesting baked egg, EW-induced skin prick test wheal diameter and EW-, ovalbumin-, and ovomucoid-specific IgE levels decreased significantly, while ovalbumin- and ovomucoid-specific IgG(4) levels increased significantly. Subjects in the per-protocol group were 14.6 times more likely than subjects in the comparison group (P< .0001) to develop regular egg tolerance, and they developed tolerance earlier (median 50.0 vs 78.7 months; P< .0001). Initiation of a baked egg diet accelerates the development of regular egg tolerance compared with strict avoidance. Higher serum EW-specific IgE level is associated with persistent baked and regular egg reactivity, while initial baked egg reactivity is not.

Concordance of Lateral Flow and Skin Prick Tests in the Assessment of Allergen Sensitisation in the Epidemiological Field in Children

Background: A new lateral flow test (LFT) for office use provides information about sensitisation to common allergens. Concordance between LFT and skin-prick test (SPT) has not been assessed in epidemiological studies. The aim of this study is to determine LFT-SPT concordance in this field. Methods: Plasma samples (n = 270) from children aged 9–12 years previously SPT tested were used for the analysis. We selected 180 samples from children SPT positive to any of the 6 allergens which were common to SPT and LFT (cat, birch, timothy-grass, olive, pellitoryand Dermatophagoides pteronyssinus), and 90 samples from children SPT negative. The intensity of the LFT colour line which indicates a positive reaction was rated from 0 to 4. Results: Only results on cat, olive and D. pteronyssinus were analysed, as only these had an acceptable number of individuals. When atopy was defined as at least 1 wheal with a mean diameter ≧3 mm, agreement was excellent (Cohen’s ĸ = 0.81) when a lightly visible line was considered positive in the LFT, and dropped substantially (Cohen’s ĸ = 0.68) when this value of LFT was considered negative. The correlation between the SPT wheal diameter and the intensity of the LFT line was 0.71 for cat, 0.81 for olive and 0.78 for D. pteronyssinus.Conclusions: As compared to SPT, LFT is a reliable method to screen for sensitisation to cat dander, olive pollen and D. pteronyssinus in the epidemiological field among schoolchildren. There is a good correlation between the SPT wheal diameter and the intensity of the LFT line.

The diagnosis and management of egg allergy

Egg allergy is a common food hypersensitivity in children. Atopic dermatitis represents the main clinical manifestation in infancy. On first exposure, many of these infants present with urticaria, angioedema, or anaphylaxis. The role of egg allergy in gastrointestinal conditions is less well understood. The "gold standard" for the diagnosis of egg allergy is the double-blind, placebo-controlled food challenge. Diagnostic cut-off levels have been defined for food-specific serum immunoglobulin E antibody level and skin prick test wheal diameter that predict an adverse challenge outcome. This has significantly reduced the need for formal food challenges. Atopy patch testing, in conjunction with immunoglobulin E-based tests, may further improve the accuracy of predicting a positive challenge. The treatment of egg allergy consists of dietary elimination, or a maternal elimination diet in breast-fed infants. Approximately two thirds of infants with egg allergy will become tolerant by 7 years of age.

Allergens, IgE, mediators, inflammatory mechanisms: Immunoblotting analysis of twin sera provides evidence for limited genetic control of specific IgE to house dust mite allergens

Background: Although some studies have shown genetic control of specific IgE responses to purified grass allergens, studies with other allergens have not supported this. The extent of such control for house dust mite (HDM) (Dermatophagoides pteronyssinus) allergens is unclear. Objective: We sought to determine the extent to which genetic factors control the specificity of IgE responses to individual HDM allergens by comparing the immunoblot patterns of IgE binding of serum from monozygotic and dizygotic members of a large cohort of Australian twins. Methods: HDM proteins separated by sodium dodecylsulfate–polyacrylamide gel electrophoresis were immunoblotted with sera from 317 twin pairs in which at least one twin had at least a weak HDM skin test response. Concordance levels for IgE binding to the individual HDM components were compared in the subset of 142 pairs of twins in which both twins were allergic to HDMs (skin prick test wheal diameter, > 3 mm). Results: Over all 36 blotted bands, the mean case-wise concordance was 41% for monozygotic twins and 17% for dizygotic twins. Of the components detected, only those of molecular weights 23 kd and 16 kd were significantly different between the groups ( p < 0.01). Differences observed between the monozygotic and dizygotic twins could be partly explained by overall IgE hyperresponsiveness. Conclusion: Evidence for genetic control of IgE responses to 36 IgE-binding HDM components from a large sample of twins showed significant differences in concordance for two components and nonsignificant differences for several others. In the monozygotic twins, concordance never exceeded 67% for any band, and most monozygotic individuals recognized> components their co-twin did not. Genetic control of overall atopy in monozygotic twins is far stronger than that controlling specific sensitization to HDM allergens. (J Allergy Clin Immunol 1998;101:491-7.)