Nut Allergy Research Articles

Hyper IgE syndrome with autoimmune hemolytic anemia in Saudi Arabia

Background: Hyper IgE syndrome (HIES) is a rare primary immunodeficiency disorder characterized by elevated serum immunoglobulin E (IgE) levels. Autosomal dominant and autosomal recessive forms of HIES have been reported. Autosomal recessive HIES typically includes a history of asthma, atopic dermatitis, food allergy, and recurrent viral infection. HIES diagnosis requires genetic study, which is time-consuming and not always feasible. Case Presentation: We report the case of an 8-year-old female. The patient recently presented to our emergency department with pallor and syncope. Upon examination, the hemoglobin level was 4.9 g/dl. Direct antiglobulin test showed a positive result. The patient had an admitting diagnosis of autoimmune hemolytic anemia, a rare complication of autosomal recessive HIES. The patient is a known case of asthma, herpetiformis dermatitis, nut allergy, and allergic rhinitis. HIES was the first possible diagnosis, which was further confirmed by clinical presentation and a high serum IgE count. The patient was referred to a tertiary care center for genetic counseling and further follow-up. Conclusion: HIES is a rare immune deficiency disorder that can be inherited in either an autosomal dominant or recessive pattern. Although these two types show similar clinical presentations, certain features remain distinct, providing a valuable insight into the final diagnosis even without the gene study results. To the best of our knowledge, no study has evaluated HIES in general, and no case report has evaluated autosomal recessive HIES in Saudi Arabia. This case study will guide the medical community in the early-stage diagnosis and management of HIES.

Peanut-Induced Anaphylaxis in Children: A Literature Review.

Peanut allergy has become more common among children and is considered one of the most common triggers for fatal anaphylaxis. Treatment of symptoms during a reaction is only one aspect of managing anaphylaxis; other elements include rigorous dietary avoidance and education about settings that could put the patient at a high risk of unintentional exposure. We aimed to review the prevalence, mechanism, diagnosis, treatment, and emergency action of peanut-induced anaphylaxis among children. We used a web-based literature search using the advanced features of databases such as PubMed, Scopus, Directory of Open Access Journals (DOAJ), Embase, Google Scholar, and Cochrane electronic databases. The most common food to cause fatal anaphylaxis and a common cause of food allergies is peanuts. Over the past two years, our knowledge improved more about peanut allergens, their prevalence, causes, diagnoses, and treatments. The research cited in this review demonstrates that the peanut allergens are most closely associated with disease differ across cultures, that early oral peanut exposure may reduce the occurrence of peanut allergy while early non-oral exposure may have the opposite effect, that complement activation by peanut constituents appears to promote peanut-induced anaphylaxis, and that oral immunotherapy, anti-IgE antibody, and a herbal formulation are all demonstrating promise as treatments.To conclude, peanut allergies have increased frequently during the past 10 years, especially in Westernized nations. Given that peanut allergy poses a danger for fatal anaphylaxis, response management is crucial. The current standard of care for those with nut allergies comprises complete food avoidance and the administration of injectable epinephrine to treat systemic symptoms.

当センター救急外来を受診した小児木の実類アレルギー患者の特徴

日本の小児における木の実類アレルギーの増加が報告されているが，小児の救急受診患者の背景や誘発症状を検討したものはなく，当センターにおける状況を分析した．

IgE binding epitope mapping with TL1A tagged peptides

Linear IgE epitopes play essential roles in persistent allergies, including peanut and tree nut allergies. Using chemically synthesized peptides attached to membranes and microarray experiments is one approach for determining predominant epitopes that has seen success. However, the overall expense of this approach and the inherent challenges in scaling up the production and purification of synthetic peptides precludes the general application of this approach. To overcome this problem, we have constructed a plasmid vector for expressing peptides sandwiched between an N-terminal His-tag and a trimeric protein. The vector was used to make overlapping peptides derived from peanut allergens Ara h 2. All the peptides were successfully expressed and purified. The resulting peptides were applied to identify IgE binding epitopes of Ara h 2 using four sera samples from individuals with known peanut allergies. New and previously defined dominant IgE binding epitopes of Ara h 2 were identified. This system may be readily applied to produce agents for component- and epitope-resolved food allergy diagnosis.

Predictors of anaphylaxis to peanut and tree nuts in a Mediterranean population.

Background: Peanuts (PN) and tree nuts (TN) are major causes of anaphylaxis worldwide. We aimed to determine the clinical and demographic characteristics associated with anaphylaxis in patients sensitized to PN and/or TN in a Mediterranean population. Methods: We conducted a retrospective study, which included 198 patients allergic to PN and/or TN (allergy symptoms plus specific immunoglobulin E [sIgE] sensitization), evaluated in consultations from January 2015 to December 2020. Univariate analysis and multivariate logistic regression models were developed, including demographic, clinical, and laboratory data as independent variables, and anaphylaxis to each PN and/or TN as a dependent variables. Results: Anaphylaxis was associated with an earlier age of onset of allergy to PN, cashew and/or pistachio, and pine nut allergy but not to other TN allergies. Gender, atopic comorbidities, and cofactors were not associated with PN and/or TN anaphylaxis. Anaphylaxis to PN, cashew and/or pistachio, and pine nut were associated with reactivity to a fewer number of PN and/or TN foods. Although sIgE sensitization to lipid transfer proteins (LTP) was highly prevalent in our population, only seed storage protein (SSP) positivity was associated with anaphylaxis in PN allergy. The absence of pathogenesis-related protein family 10 sensitization correlated with PN and hazelnut anaphylaxis. A higher level of sIgE to almond extract predicted anaphylaxis but the level of sIgE to other PN and/or TN extracts did not predict it. Conclusion: The high prevalence of sensitization to the pan-allergen LTP did not seem to have a significant impact in PN and/or TN allergy severity in our study. Instead, other factors, such as early age of onset and positivity for SSPs, seem to strongly associate with anaphylaxis to specific PN and/or TN. These findings may contribute to individual risk assessment in these populations.

IMPACT OF EARLY PEANUT INTRODUCTION GUIDELINES ON INFANT TREE NUT ALLERGY TESTING

<h3>Introduction</h3> Tree nut allergy, like peanut allergy, is a common cause of severe food allergic reactions. The impact of the 2017 early peanut introduction guidelines on tree nut allergy testing in infants has not been well studied. <h3>Methods</h3> We performed a retrospective cohort study of infants less than age 1 year with Kaiser Permanente Northern California insurance coverage and had food-specific sIgE testing from January 2015 to December 2020. Our outcome of interest was sIgE testing rates for the following tree nuts: almond, Brazil nut, cashew, hazelnut, pecan, pistachio, and walnut. <h3>Results</h3> Among 3340 infants undergoing food-specific sIgE testing, the sIgE testing rates (per 1000 infants) increased for all tree nuts studied from 2015 to 2020 (p<0.001, Figure). Year-to-year analysis showed that sIgE testing rates increased for most tree nuts from 2017 to 2018 following publication of the early peanut introduction guidelines: almond (p=0.001), Brazil nut (p=0.001), hazelnut (p=0.001), pecan (p=0.004), and pistachio (p=0.002). sIgE testing rates for cashew and walnut also trended upward but decreased significantly from 2018 to 2019 following removal of a food allergy screening panel containing both nuts (p=0.01 for cashew, p=0.035 for walnut). <h3>Conclusion</h3> Infant sIgE testing rates increased significantly for all tree nuts following the 2017 early peanut introduction guidelines and decreased for selected tree nuts following removal of a food allergy screening panel. More studies are needed to assess the utility of tree nut sIgE testing in infants and the impact of early food introduction on tree nut allergy prevalence.

A 5 YEAR-OLD BOY WITH ATYPICAL UPPER LIP SWELLING

<h3>Introduction</h3> Lip swelling is a common chief complaint in the allergy clinic, but not all swelling is angioedema. Clinicians should keep their differential diagnoses broad when evaluating these patients. This is a case of lymphatic malformation (LM) in a boy with atypical upper lip swelling. <h3>Case Description</h3> A 5-year-old boy with a past medical history of asthma, tree nut allergy, allergic rhinitis, and atopic dermatitis presented for evaluation of persistent upper lip and maxillary gingival swelling. His lip swelling started suddenly and persisted for two years. The family reported intermittent "white fluid" drainage from the affected gingiva. Physical examination showed diffuse upper lip swelling and maxillary gingival swelling. Given his clinical history, his family and pediatrician attributed this swelling to an allergic reaction. He reported no improvement with daily antihistamines, but he did experience transient improvement with oral steroids. Contrast enhanced facial MRI was nonspecific, demonstrating a poorly defined area of mucosal thickening involving the upper lip and anterior maxillary alveolar ridge. He was evaluated by pediatric ENT who referred him to pediatric neurointerventional radiology for suspicion of LM. An ultrasound demonstrated a microcystic LM, notable for tiny anechoic areas without internal flow in the superior lip. The parents are considering definitive diagnosis with a biopsy and treatment options such as sclerotherapy. <h3>Conclusion</h3> LMs can be misdiagnosed as angioedema and should be considered in the differential diagnoses in patients with atypical lip swelling. Contrast enhanced MRI and ultrasound with color Doppler imaging are the recommended imaging modalities for evaluation.

IMPACT OF INTRODUCING SUBGROUPS OF TREE NUTS VERSUS COMPLETE AVOIDANCE ON QUALITY OF LIFE

<h3>Introduction</h3> Tree nut allergies can impact quality of life (QoL) of children and their caregivers. Many patients are only allergic to a subgroup of tree nuts and may be cleared to eat other tree nuts. However, data on the QoL impact of introducing limited subgroups of tree nuts versus complete avoidance is sparse. <h3>Methods</h3> This longitudinal observational prospective study evaluated change in QoL score in tree nut allergic patients at baseline while avoiding all tree nuts, versus after successful oral food challenge (OFC) for individual tree nut subgroups. Pediatric patients and their caregivers were given the Food Allergy Quality of Life Questionnaire (FAQLQ) before and one month after OFC. 27 patients were enrolled, with 7 who completed both baseline and post-challenge FAQLQ. Higher score indicates worse QoL. <h3>Results</h3> Of the children that underwent tree nut challenge, the mean parent or teen FAQLQ score at baseline and post-challenge was 1.51 and 1.56, respectively. Some families declined individual tree nut challenge. Characteristics of these patients versus those who proceeded with OFC were examined. There were no statistical differences in parental FAQLQ, race, health insurance, history of tree nut reaction, comorbid peanut allergy, comorbid asthma, or comorbid eczema. Those who proceeded with OFC had a significantly higher rate of comorbid allergic rhinitis versus those who declined <h3>Conclusion</h3> Quality of life did not significantly improve after patients were cleared of a single tree nut subgroup allergy label. Shared decision making with patients and guardians should be employed when deciding on tree nut subgroup challenges.

CHALLENGES IN MANAGING THE LATE ADOLESCENT PATIENT ON PALFORZIA

<h3>Introduction</h3> Palforzia [Peanut Allergen Powder-dnfp] is the only FDA-approved therapy to minimize the potential for life-threatening anaphylactic reactions to peanut in children. Given the inherent risks, the dosing schedule must be followed exactly. <h3>Case Description</h3> L.B. is a 17-year-old male with severe peanut anaphylaxis, tree nut allergy, and asthma. He began Palforzia in November 2021. All required parties completed the Risk Evaluation and Mitigation Strategy program. A detailed binder created by our nursing staff containing dosing procedures and a dose tracker was provided. Phone calls were made 3 days after each Up-dose. Various issues occurred during treatment. He once forgot to eat breakfast before an Up-dose and was given food in our clinic first. In December, he developed anaphylaxis from tree nut ingestion but only informed our office after 2 days. In January, he began having abdominal pain and diarrhea with each Up-dose. With questioning, he reported taking the doses late at night without parental supervision, on an empty stomach, or going to the gym within 3 hours of the dose. We frequently reviewed the proper dosing protocol and cautioned that treatment would stop if he was noncompliant. Famotidine helped the gastrointestinal symptoms. He achieved Maintenance in April but stopped Palforzia by June 2022. <h3>Discussion</h3> We learned that the care of late adolescents on Palforzia poses particular challenges. Open communication and full engagement with the patient and family are critical throughout the process. Going forward, we must respect their lifestyle and growing autonomy so they can safely incorporate Palforzia into their daily routine.

EFFICACY OF PINE NUT-SPECIFIC IGE TESTING PRIOR TO ORAL FOOD CHALLENGE

<h3>Introduction</h3> Allergy to nuts is a common, well documented condition in the pediatric population, however allergy to pine nuts specifically is a relatively rare phenomenon. The efficacy of pine nut-specific IgE testing prior to a pine nut oral food challenge (OFC) remains unclear and may represent an unnecessary step in clinical management. <h3>Methods</h3> Retrospective chart review was performed on fourteen patients with documented pine nut allergy who underwent pine-nut specific IgE testing prior to the pine nut OFC. The charts were reviewed for demographic data, pine nut specific IgE testing, total IgE testing, other food allergies, atopic conditions, and the pine nut OFC results. <h3>Results</h3> All fourteen patients were found to have a history of atopic conditions and other food allergies. Eleven of the patients had no known exposure to products containing pine nuts and the other three patients had unclear exposure history. Average total IgE=591.18 (SD:428.94, N:11) and pine nut-specific IgE=1.31 (SD:1.10, N:14). Twelve of the fourteen patients who ingested products containing pine nuts passed the pine nut OFC and introduced pine nut-containing products into their diet. Their average pine nut-specific IgE=1.10 (SD:1.06, N:12) while those who failed their pine nut OFCs had an average pine nut-specific IgE=2.36 (SD: 0.81, N:2). <h3>Conclusion</h3> This study suggests that there is no clinical correlation between pine-nut specific IgE level with passing or failing an OFC.

The correlation between food sensitivity, sex, age of patients and some physiological problems

Food allergy/hypersensitivity refers to situations in which an immune process (IgE- or non-IgE-mediated) can be demonstrated (for example, bovine milk, peanut, or soybean hypersensitivity), whereas food intolerance is a form of food allergy identified depending on the existence of IgG antibodies. In our study we wanted to look at the association between food intolerance/ sensitivity and certain physiological problems, as well as the association between food sensitivity and age. The experimental groups used consist of eighty patients age ranged from (1- 70) years old, they are divided into three groups: group1 (age range 1-10 years old), group 2(age range 10-40 years old) and group 3 (age range 40-70 years old). We measured the level of antibodies that formed against each food group, these results represented in numbers as the following: 1: no sensivity, 2: sensitivity, 3,4: strong sensitivity. Our results showed that the highest percentage of food allergy in group 1 was cow milk and wheat allergy (34.6% and 30.7%) respectively, the highest percentage of food allergy in group 2 was pea nut and red pepper allergy (28.12% and 21.87%), respectively. Table 6 showed that the highest percentage of food allergy in group 3 also was in pea nut and red pepper, but the percentage was lower than that of group 2. While the whole allergy in group 3 was higher than the whole allergy of groups 1 and 2. Finally, this study adds to our understanding of the incidence as well as longterm characteristics of food allergy not just in kids, but also in middle age people and adults.

Induction of food-specific IgG by Gene Gun-delivered DNA vaccines

Shellfish and tree nut allergies are among the most prevalent food allergies, now affecting 2%-3% and 1% of the US population, respectively. Currently, there are no approved therapies for shellfish or tree nut allergies, with strict avoidance being the standard of care. However, oral immunotherapy for peanut allergy and subcutaneous immunotherapy for environmental allergens are efficacious and lead to the production of allergen-specific IgG, which causes suppression of allergen effector cell degranulation. Since allergen-specific IgG is a desired response to alleviate IgE-mediated allergies, we tested transcutaneously-delivered DNA vaccines targeting shellfish and tree nut allergens for their ability to induce antigen-specific IgG, which would have therapeutic potential for food allergies. We assessed Gene Gun-delivered DNA vaccines targeting either crustacean shellfish or walnut/pecan allergens, with or without IL-12, in naïve mice. Three strains of mice, BALB/cJ, C3H/HeJ and CC027/GeniUnc, were evaluated for IgG production following vaccination. Vaccines were administered twice via Gene Gun, three weeks apart and then blood was collected three weeks following the final vaccination. Vaccination with shellfish allergen DNA led to increased shrimp-specific IgG in all three strains, with the highest production in C3H/HeJ from the vaccine alone, whereas the vaccine with IL-12 led to the highest IgG production in BALB/cJ and CC027/GeniUnc mice. Similar IgG production was also induced against lobster and crab allergens. For walnut/pecan vaccines, BALB/cJ and C3H/HeJ mice produced significantly higher walnut- and pecan-specific IgG with the vaccine alone compared to the vaccine with IL-12, while the CC027 mice made significantly higher IgG with the addition of IL-12. Notably, intramuscular administration of the vaccines did not lead to increased antigen-specific IgG production, indicating that Gene Gun administration is a superior delivery modality. Overall, these data demonstrate the utility of DNA vaccines against two lifelong food allergies, shellfish and tree nuts, suggesting their potential as a food allergy therapy in the future.

Macadamia nut-specific IgE levels for predicting anaphylaxis.

Despite the high risk of anaphylaxis in patients with a macadamia nut allergy (MdA), little is known about the significance of macadamia nut-specific immunoglobulin E (Md-sIgE). Thus, this study aimed to investigate the utility of Md-sIgE for predicting anaphylaxis. Children with suspected MdA who visited our hospital were included. MdA was defined as either failing the 3-g macadamia nut (Md) oral food challenge (OFC) or confirming obvious immediate symptoms following Md ingestion. Non-MdA was defined as passing the 3-g Md OFC. A total of 41 children (29 [71%] males) with a median age of 7.7 years were included. The median Md-sIgE level was 2.23 kUA /L. Among the 21 children diagnosed with MdA, eight and 13 children did (An group) and did not (non-An group) develop anaphylaxis. Twenty children were included in the non-MdA group. The Md-sIgE level was significantly higher in the An group relative to the others (7.97 vs. 1.92 kUA /L, p < .001). Furthermore, the Md-sIgE level was significantly higher in the An group than in the non-An group (7.97 vs. 1.92 kUA /L, p=.02). However, there was no significant difference in the Md-sIgE between the non-An and non-MdA groups (1.92 vs. 1.90 kUA /L, p > .99). The area under the curve for predicting anaphylaxis in Md-sIgE was 0.92 (95% CI: 0.83-1.00), and the optimal cut-off value was 3.76 kUA /L. Md-sIgE levels were useful in predicting anaphylaxis. Above the cut-off value, we emphasize paying careful attention to the risk of anaphylaxis.

Feasibility of the ALEX multiplex platform in the diagnosis of nut allergy from a Mediterranean population

BackgroundALEX multiplex platform has been recently commercialized but its clinical utility as quantitative technique respect to ImmunoCAP-singleplex as the reference method has not yet been confirmed on patients suffering from nut allergy and co-sensitization to different nuts. Methods58 serum samples from patients with nut allergy from a Mediterranean population were assayed in parallel by ALEX-multiplex and ImmunoCAP-singleplex techniques. Patients were diagnosed based on clinical symptoms and positive skin prick tests (SPTs). The following whole extracts were compared between both techniques: walnut, hazelnut, peanut, almond, pistachio and sunflower seed; besides the recombinant Pru p 3. A qualitative and quantitative study was carried out. ResultsBoth techniques had similar sensitivities respect to whole extracts from walnut, hazelnut and peanut as well as to Pru p 3 (p > 0.05). However for whole extracts from almond, pistachio and sunflower seed the sensitivity obtained by ALEX was much lower than ImmunoCAP (9.09 % vs 88.63 %; 14.81 vs 70.37 %; and 8.51 % vs 88.88 %; respectively). The concordance between both techniques showed only a substantial agreement for Pru p 3 (k = 0.791); moderate agreement for hazelnut and peanut (k = 0.550 and k = 0.544, respectively); fair agreement for walnut (k = 0.386) and poor agreement for almond, pistachio and sunflower seed (k < 0.2). Quantitative analysis showed that ImmunoCAP for walnut, peanut and sunflower seed had higher mean values than ALEX. Relationships were significant for all specific IgE levels except to for almond, pistachio and sunflower seed. ConclusionsALEX platform is a suitable technique to patients with nut allergy from the Mediterranean area except to for those suffering from allergy to almond, pistachio and sunflower seed.

BSACI guideline for the diagnosis and management of pollen food syndrome in the UK.

Pollen food syndrome (PFS) is a highly prevalent food allergy affecting pollen-sensitized children and adults. Sufferers experience allergic symptoms when consuming raw plant foods, due to the homology between the pollen allergens and unstable proteins in these foods. The triggers involved can vary depending on the pollen sensitization, which in turn is affected by geographical location. The British Society of Allergy and Clinical Immunology (BSACI) Standards of Care Committee (SOCC) identified a need to develop a guideline for the diagnosis and management of PFS in the United Kingdom (UK). Guidelines produced by the BSACI use either the GRADE or SIGN methodology; due to a lack of high-quality evidence these recommendations were formulated using the SIGN guidelines, which is acknowledged to be less robust than the GRADE approach. The correct diagnosis of PFS ensures the avoidance of a misdiagnosis of a primary peanut or tree nut allergy or confusion with another plant food allergy to non-specific lipid transfer proteins. The characteristic foods involved, and rapid-onset oropharyngeal symptoms, mean PFS can often be diagnosed from the clinical history alone. However, reactions involving tree nuts, peanuts and soya milk or severe/atypical reactions to fruits and vegetables may require additional diagnostic tests. Management is through the exclusion of known trigger foods, which may appear to be simple, but is highly problematic if coupled with a pre-existing food allergy or for individuals following a vegetarian/vegan diet. Immunotherapy to pollens is not an effective treatment for PFS, and although oral or sublingual immunotherapy to foods seems more promising, large, controlled studies are needed. The typically mild symptoms of PFS can lead to an erroneous perception that this condition is always easily managed, but severe reactions can occur, and anxiety about the onset of symptoms to new foods can have a profound effect on quality of life.

One-year investigation of nut allergy cases in children referred to the allergy clinic of the children's medical center

Background: The prevalence of allergy to tree nuts is spreading worldwide. Allergy to tree nuts causes more severe clinical symptoms and anaphylaxis attacks are more likely. The present study was conducted in order to investigate the cases of tree nut allergy among children referred to the allergy clinic of the Children's Medical Center in a period of one year (from the beginning of 2018 to its end). Methods: There were 1920 children with a history of atopic disease (asthma, allergic rhinitis, atopic dermatitis, chronic urticaria) with a history of type I allergic reactions. Eighty seven patients with skin, digestive, respiratory symptoms or anaphylaxis after consuming tree nuts were included in the study. A skin test was performed for most of these people, and in some cases, the serum specific IgE level against the desired nuts was requested, and after confirming the positive history of allergy by the mentioned tests, a questionnaire containing 26 questions was completed by the parents to complete the information. Findings: The prevalence of allergy to tree nuts in the studied population was 4.5%. Allergy to almonds is at the top with a frequency of 62.1%. Totally, 55.2% of the patients were males.

Limbic Keratoconjunctivitis Associated With Dupilumab Treatment in Atopic Dermatitis

A 22-year-old Asian American man was seen for atopic dermatitis, pollenosis, oral allergy syndrome, and peanut/tree nut allergies in August 2017. He had a history of hypothyroidism and childhood eczema but no history of eye disease or prior ophthalmology visits. Examination revealed atopic dermatitis of hands, head, neck, and legs. His past treatment included corticosteroid and calcineurin inhibitor creams and allergen immunotherapy. The IgE level was 1792 kU/L, and blood eosinophils were 600/mm3.

Clinical and prognostic evaluation of legumes and tree nuts allergy in children

PurposeAllergy to legumes and tree nuts (TNs) is one of the most important causes of fatal and near-fatal food-induced allergic reactions. However, our knowledge of the clinical features of legumes and TNs allergies in children is limited. In this study, we aim to identify clinical characteristics, development of tolerance, risk factors of legumes and TNs allergies in children. MethodsThis retrospective study was designed at two cities at the west part of Turkey. Fifty-seven children with legumes and TNs diagnosed at Clinic of Pediatric Allergy of Balikesir University and Dr Behcet Uz Children Hospital for 2014–2018 years were examined. Current age, gender, age of onset of the legumes and/or TN allergy, the type of the allergic reactions, family history of atopy, results of skin prick test (SPT), and/or oral challenge test and presence of concomitant food allergies, tolerance development and cross reactions were recorded. ResultsIn total, 83 allergies related with legumes and TNs were determined in 57 patients. Mean age of patients was 18.75±13 months and 40.4% were girl. Fifty-two of these reactions were related with legumes (62.6%) and 29.9% of patients had reaction with more than one. Peanut allergy was most common in legumes allergy (53.8%) and walnut allergy was most common in TNs allergy (54.8%). Urticaria was most common type of allergic reaction (56.6%), 28.9% of reactions were anaphylaxis. No statistically significant difference was found between legumes and TNs in terms of the frequency of development of anaphylaxis (P=0.062). Concomitant food allergy was present 80.7% of patients. Patients with legume allergy had significantly high hazelnut and walnut allergy (P=0.04, P<0.001, respectively). Significantly, high peanut and lentil allergy were detected in patients with TNs allergy (P=0.01, P=0.026, respectively). There was co-sensitization and co-allergy between legumes and TNs in children as expected. Tolerance development was shown in 12.2% of patients. ConclusionsIn addition to other food allergies, legumes/TNs allergies are also observed to occur with increasing frequency in children. Co-sensitization and co-allergy between legumes and TNs are frequent. Tolerance development for legumes/TNs allergies is expectedly low.

Onset of Nut Allergy in a Pediatric Cohort: Clinical and Molecular Patterns in the AFRUSEN Study.

Nut allergy is a growing problem, yet little is known about its onset in children. Objective: To characterize the onset of nut allergy in children in southern Europe. The study population comprised consecutive patients up to 14 years of age who visited allergy departments with an initial allergic reaction to peanut, tree nut, or seed. The allergy work-up included a clinical history, food challenge, skin prick testing, determination of whole-extract sIgE, and ImmunoCAP ISAC-112 assay. Of the 271 children included, 260 were first diagnosed with nut allergy at a mean age of 6.5 years and at a mean (SD) of 11.8 (21.2) months after the index reaction. The most common culprit nuts at onset were walnut (36.5%), peanut (28.5%), cashew (10.4%), hazelnut (8.5%), pistachio (5.4%), and almond (5%). Onset of peanut allergy was more frequent in children ≤6 years and walnut in those aged >6 years (P=.032). In 65% of cases, the allergic reaction occurred the first time the patient consumed the nut, and 35% of reactions were anaphylactic. Overall, polysensitization to nuts was detected by skin prick testing in 64.9% of patients, although this rate was lower among walnut-allergic children (54.7%) and peanut-allergic children (54.1%) (P<.0001). Sensitization to 2S albumins was predominant (75%), especially Jug r 1 (52.8%), whereas sensitization to lipid transfer proteins was less relevant (37%). In the population we assessed, the onset of nut allergy occurred around 6 years of age, slightly later than that reported in English-speaking countries. Walnut was the main trigger, followed by peanut. 2S albumin storage proteins, especially Jug r 1, were the most relevant allergens. This study will help guide management and may contribute to preventive strategies in pediatric nut allergy.

A practical focus on oral immunotherapy to tree nuts.

Tree nut (TN) allergy is common, with a global prevalence of up to 4.9%. TN allergy is persistent in most patients, and accidental reactions are common. There is considerable clinical cross-reactivity between cashew and pistachio, and between walnut and pecan. A diagnosis of TN allergy is based on a history of clinical reaction on ingestion, along with confirmed sensitization through either skin-prick or serum immunoglobulin E (IgE) testing. Component testing and food challenges may be required in patients with birch pollinosis to distinguish between IgE-mediated allergy to a heat-stable protein and pollen food allergy syndrome. There is available evidence that TN oral immunotherapy (OIT) is reasonably safe and effective. There are numerous nonpharmaceutical food products to facilitate TN-OIT dosing. TN OIT should be offered as a treatment option for patients with TN allergy.