Pru p 3-specific IgE affinity is crucial in severe peach-allergy patients.

Background: Peach allergy is common food allergen. Allergen components-specific antibodies of different isotypes in peach-allergy patients are poorly studied. Factors other than Pru p 3-sIgE levels may be related to severe symptoms. Objective: To evaluated peach component-specific-IgE, IgG1, and IgG4 characteristics in individuals with and without peach allergy, and Pru p 3-sIgE affinity in patients with different clinical symptoms. Methods: Fifteen healthy controls and 32 peach-allergy patients were enrolled. sIgE, sIgG1, and sIgG4 to 5 Escherichia coli-expressed peach-allergen components were determined by enzyme-linked immunosorbent assays. Pru p 3-sIgE affinity was measured in Pru p 3-sIgE-positive patients, using immunoadsorbance. Results: Patients were divided into oral allergy syndrome (OAS) and peach-induced anaphylaxis (PIA) groups. Serum Pru p 1-, Pru p 2-, Pru p 3-, Pru p 4-, and Pru p 7-sIgG1s were detected. Pru p 1- and Pru p 2-sIgG1 levels were higher in healthy controls, but Pru p 3-sIgG1 levels were significantly higher in peach-allergy patients. Pru p 1-, Pru p 3-, and Pru p 4-sIgG4-positivity was significantly greater among patients than among controls. Pru p 3 was the predominant allergen in peach-allergy patients. Allergen-sIgG1 and sIgG4 were similar between OAS and PIA patients. Pru p 3-sIgE levels were significantly higher in PIA patients, but Pru p 3-sIgE-positivity was similar in both groups. In Pru p 3-sIgE-positive patients, Pru p 3-sIgE affinity was significantly higher in PIA than OAS patients. Conclusions: Allergen-sIgG1 was associated with allergen exposure. Both Pru p 3-sIgE levels and affinity are key factors in severe peach-allergy patients.

Favorable clinical course after discontinuation of omalizumab treatment in patients with allergic severe asthma: A real-world clinical practice.

The success rate of omalizumab discontinuation is 50-75.5%. However, such data are scarce in Japan. We retrospectively investigated the clinical progression following the cessation of long-term omalizumab treatment (>5 years) in severe allergic asthma patients who have achieved super-responder status, defined as being off any oral maintenance corticosteroids without experiencing exacerbations requiring systemic corticosteroids for >1 year. Six (28.6%) among 21 patients recommenced after a median period of 5.5 (4.3-12.5) months later due to exacerbated asthma control, resulting in improved asthma management for all patients. The rates of patients who successfully remained off omalizumab treatment for 1 and 2 years were 72.4% and 65.8%, respectively. Specific IgE levels after discontinuing omalizumab treatment significantly decreased compared to those at initiating this treatment in 10 patients who successfully remained off this treatment. Therefore, discontinuing omalizumab treatment may be considered for patients continuing treatment beyond 5 years and achieving super-responder status.

JACQLQ subjective symptom questionnaire score and clinical test results for patients with allergic conjunctival disease.

We investigated the relationship between subjective symptoms and objective findings in patients with allergic conjunctival diseases (ACD) and test results for tear total IgE (t-tIgE), conjunctival eosinophils (c-Eo), serum total IgE (s-tIgE), serum-antigen specific IgE (s-sIgE), and serum eosinophils (s-Eo). Subjective symptoms and objective findings of patients with ACD were evaluated using Japanese Allergic Conjunctival Disease Quality of Life Questionnaire (JACQLQ), which described disability score and emotional score written by patient and clinical findings score written by ophthalmologist. We investigated the relationship between questionnaire scores and laboratory data for t-tIgE, c-Eo, s-tIgE, s-sIgE, and s-Eo. Scores of impediments to life and of moods were highest in vernal keratoconjunctivitis among ACD. Cases with positive pollen-sIgE showed significantly more nasal symptom score than those with negative pollen-sIgE (P < 0.05). Cases with positive t-tIgE or c-Eo showed significantly more objective symptoms' JACQLQ score than those with negative t-tIgE or c-Eo (P < 0.05), respectively. Cases positive for house dust/mite-sIgE, showed significantly more objective symptoms' JACQLQ score than those without for house dust/mite-sIgE (P < 0.05). These results indicate that ACD could be analyzed more accurately by the combination of JACQLQ and laboratory data.

High Serum Allergen-Specific IgE of House Dust Mite in Predicting the Risk of Comorbidity in Children with Allergic Conjunctivitis.

Purpose: To investigate the patterns of allergens in allergic conjunctivitis (AC) and the association with allergic comorbidity. Methods: This retrospective cross-sectional study enrolled 2972 children with AC. Clinical data, including sex, age, allergic comorbidities (allergic asthma, allergic rhinitis, and atopic dermatitis), and serum allergen-specific immunoglobulin E (sIgE), were collected from the electronic medical record (EMR). The categorical variables were compared with the chi-square test. The characteristics of allergens in children of different ages and comorbidities were analyzed by trend chi-square. The sensitivity level of HDM associated with AC and comorbidities was assessed by odds ratios (ORs) with 95% confidence intervals of logistic regression analysis. Results: A total of 2972 children (2015 boys and 957 girls) with AC were included in the study. The mean age was 3.78 (0.5~12) years. The most common allergen was house dust mite(HDM) (43.41%). With age, the positive rate for inhaled allergens gradually increased, and the positive rate for ingested allergens decreased. With the number of comorbidities increasing, the positive rates of sensitization were 38.33%, 74.51%, 80.72%, and 89.05%, and the incidence of polysensitization was 44.66%, 56.48%, 59.54%, and 74.59%, respectively. With the increase of HDM-sIgE level, the number of comorbidities and the risk increased gradually. Conclusion: HDM is the most common allergen in AC children of different ages. High levels of HDM-sIgE may be a predictor for allergic comorbidities. Children with polysensitization and high levels of HDM sIgE will be an important target population for future intervention in other allergy-related disease prevention.

Clinical and serological characteristics of patients allergic to LTP.

BACKGROUND: Allergy to lipid transfer proteins (LPT) is common in Mediterranean Europe, and it causes severe reactions in patients and affects multiple foods, impairing the quality of life. OBJECTIVE: This study aimed to describe the clinical and sensitization profile of patients with LTP syndrome and to determine a clinical pattern of severity. Molecular diagnosis is shown in a broad population through microarrays. MATERIAL AND METHODS: This study was performed at the LTP Allergy Consultation of the Reina Sofia Hospital in Murcia, Spain. We analyzed the patients' characteristics, reactions, cofactors, food implicated, quality of life, skin prick test to food and aeroallergens, and serologic parameters, such as total immunoglobulin E, peach LTP (Pru p 3 IgE) and immunoglobulin G4, and microarray Immuno Solid-phase Allergen Chip (ISAC). We related the severity of the reactions with other variables. RESULTS: We presented a series of 236 patients diagnosed with LTP allergy, 54.66% suffering from anaphylaxis, 36.02% from urticaria angioedema, and 9.32% from oral allergy syndrome. The most frequently implicated food was peach, producing symptoms in 70% of patients, followed by walnut in 55%, peanut in 45%, hazelnut in 44%, and apple in 38% patients. Regarding the food that provoked anaphylaxis, walnut was the most frequent instigator, along with peach, peanut, hazelnut, almond, sunflower seed, and apple. According to the severity of LPT reaction, we did not discover significant differences in gender, age, food group involved, and serologic parameters. We found differences in the presence of cofactors, with 48.84% of cofactors in patients with anaphylaxis, compared to 27.1% in patients without anaphylaxis and in family allergy background (P < 0.0001). CONCLUSION: In our series of patients, 54% presented anaphylaxis, and the foods that most frequently produced symptoms were peaches, apples, and nuts. Cofactors and family allergy backgrounds were associated with the severity of LPT reaction.

Allergic bronchopulmonary mycosis in Schizophyllum commune with positive Aspergillus-specific IgE antibodies: A case report.

Schizophyllum commune is the third most common causative fungus of allergic bronchopulmonary mycosis(ABPM). Two-thirds of ABPM caused by S. commune can be positive for Aspergillus fumigatus-specific IgE, which can be difficult to diagnose. Our patient presented to our hospital with wet cough for 3 months and chest pain for 3 days. Blood tests showed IgE 1522 IU/mL, eosinophils 688/mm3, A. fumigatus -specific IgE 2.24 UA/mL, and chest computed tomography showed high-attenuation mucus. Bronchoscopy showed mucus plugs and speculum examination showed filamentous fungi, but various culture tests did not detect A. fumigatus, Asp f 1-specific IgE was negative, and S. commune was detected in the culture of bronchial washing. Since he was positive for S. commune-specific IgE and IgG, he diagnosed ABPM caused by S. commune. These findings demonstrate the importance of identifying the causative fungus in ABPM by detailed examination.

Detection of Specific IgE against Molds Involved in Allergic Bronchopulmonary Mycoses in Patients with Cystic Fibrosis.

CONTEXT: Allergic bronchopulmonary mycoses (ABPM) can be due to molds other than Aspergillus fumigatus in patients with cystic fibrosis (pwCF). We aimed to develop immunoassays for the detection of specific IgE (sIgE) directed against five fungal species involved in ABPM: Aspergillus terreus, Scedosporium apiospermum, Lomentospora prolificans, Rasamsonia argillacea, and Exophiala dermatitidis. MATERIALS AND METHODS: Serum samples (n = 356) from 238 pwCF, collected in eight CF care centers in France, Germany, and Italy, were analyzed by dissociated enhanced lanthanide fluorescent immunoassay (DELFIA®) to assess levels of sIgE directed against antigenic extracts of each fungus. Clinical, biological, and radiological data were collected for each episode. One hundred serum samples from healthy blood donors were used as controls. Sera were classified into four groups depending on the level of sIgE according to the quartile repartition calculated for the pwCF population. A score of 4 for values above the 3rd quartile corresponds to an elevated level of sIgE. RESULTS: PwCF showed higher levels of sIgE than controls. Based on criteria from the ABPA-ISHAM working group, with an additional criterion of "a sIgE score of 4 for at least one non-A. fumigatus mold", we were able to diagnose six cases of ABPM. CONCLUSIONS: Using 417 IU/mL as the threshold for total IgE and the same additional criterion, we identified seven additional pwCF with "putative ABPM". Detection of sIgE by DELFIA® showed good analytical performance and supports the role played by non-A. fumigatus molds in ABPM. However, commercially available kits usable in routine practice are needed to improve the diagnosis of ABPM.

Association of serum total IgE and allergen-specific IgE with insulin resistance in adolescents: an analysis of the NHANES database.

BACKGROUND: Recent studies have found that total immunoglobulin E (IgE) and allergen-specific IgE were associated with some metabolic diseases. However, the role of IgE in metabolism among adolescents is still unclear. Herein, this study aims to investigate the associations of serum total IgE and allergen-specific IgE with insulin resistance (IR) in adolescents, in order to provide some reference for the prevention and treatment of metabolic diseases in a young age. METHODS: Data of 870 adolescents were extracted from the National Health and Nutrition Examination Survey (NHANES) database in 2005-2006 in this cross-sectional study. Weighted univariate and multivariate logistic regression analyses were utilized to screen covariates and explore the relationships of serum total IgE and allergen-specific IgE with IR. The evaluation indexes were odds ratios (ORs) and 95% confidence intervals (CIs). In addition, these relationships were also assessed in subgroups of allergy history, asthma history, and number of allergens. RESULTS: Among eligible adolescents, 168 had IR. No significant association between serum total IgE level and IR was found. However, adolescents with higher level of allergen-specific IgE to rye grass [OR = 0.47, 95%CI: (0.25-0.91)], white oak [OR = 0.57, 95%CI: (0.37-0.88)], or peanut [OR = 0.38, 95%CI: (0.15-0.97)] seemed to have lower odds of IR, whereas those had higher level of shrimp-specific IgE [OR = 2.65, 95%CI: (1.21-5.84)] have increased odds of IR. In addition, these associations between allergen-specific IgE and IR were also discovered in adolescents who had allergy history or asthma history, or had different numbers of allergens. CONCLUSION: Paying attention to different allergens in adolescents may be important in the early identification of IR among this high-risk population. The study results relatively provided some reference for further exploration on IR prevention.

Test Panel of Hidden Allergens for "Idiopathic Anaphylaxis" Reveals Wheat Allergy Dependent on Augmentation Factors as Common Final Diagnosis.

BACKGROUND: Idiopathic anaphylaxis (IA) is an unresolved concern. Hidden allergens may be relevant in IA and in nonsteroidal anti-inflammatory drug hypersensitivity (NSAID-HS). OBJECTIVE: To identify hidden elicitors for IA and NSAID-HS by a skin prick test (SPT) (13 allergens) and allergen-specific IgE (sIgE) panel (12 allergens) and to determine the value of each tested allergen. METHODS: We retrospectively included all patients from 2018 to 2021 referred with a suspicion of IA or NSAID-HS by history in whom SPT and/or sIgE to allergens of the IA panel were performed. Patient characteristics from patients' records included comorbidities, history and symptoms of anaphylaxis, serum baseline tryptase level, total IgE level, SPT, sIgE, challenge results, and final diagnoses. RESULTS: A total of 134 patients (77 female, mean age 39.7 ± 14.6 years) were included. Median serum baseline tryptase and total IgE levels were 4.23 µg/L and 133.5 kU/L, respectively. Allergologic workup with the IA panel resulted in positive SPT and sIgE in 61 (47%) and 66 (60%) patients, respectively. In those, confirmation or exclusion of allergy, mostly by challenge, led to a definitive diagnosis in 61 of 134 patients (46%). Skin prick test was most frequently positive to gluten (22.4%) and sIgE to ω5-gliadin (21.6%), which correlated with the history (r = 0.310, P < .001; and r = 0.407, P < .001, respectively). In 28 of 134 patients (21%) with initially suspected IA or NSAID-HS, challenges confirmed occult food allergy in which wheat allergy dependent on augmentation factors was the most frequent cause of anaphylaxis (19%). CONCLUSIONS: Wheat allergy dependent on augmentation factors should be considered in all patients with anaphylaxis of unknown cause or after NSAID intake.

Insect Cell-Expressed Major Ragweed Allergen Amb a 1.01 Exhibits Similar Allergenic Properties to Its Natural Counterpart from Common Ragweed Pollen.

Common ragweed pollen allergy has become a health burden worldwide. One of the major allergens in ragweed allergy is Amb a 1, which is responsible for over 90% of the IgE response in ragweed-allergic patients. The major allergen isoform Amb a 1.01 is the most allergenic isoform in ragweed pollen. So far, no recombinant Amb a 1.01 with similar allergenic properties to its natural counterpart (nAmb a 1.01) has been produced. Hence, this study aimed to produce a recombinant Amb a 1.01 with similar properties to the natural isoform for improved ragweed allergy management. Amb a 1.01 was expressed in insect cells using a codon-optimized DNA construct with a removable N-terminal His-Tag (rAmb a 1.01). The recombinant protein was purified by affinity chromatography and physicochemically characterized. The rAmb a 1.01 was compared to nAmb a 1.01 in terms of the IgE binding (enzyme-linked immunosorbent assay (ELISA), immunoblot) and allergenic activity (mediator release assay) in well-characterized ragweed-allergic patients. The rAmb a 1.01 exhibited similar IgE reactivity to nAmb a 1.01 in different IgE-binding assays (i.e., IgE immunoblot, ELISA, quantitative ImmunoCAP inhibition measurements). Furthermore, the rAmb a 1.01 showed comparable dose-dependent allergenic activity to nAmb a 1.01 regarding basophil activation. Overall, the results showed the successful expression of an rAmb a 1.01 with comparable characteristics to the corresponding natural isoform. Our findings provide the basis for an improvement in ragweed allergy research, diagnosis, and immunotherapy.

Diagnostic Accuracy of Specific IgE Against Wheat and Rye in Flour-Induced Occupational Asthma.

BACKGROUND: Assessment of IgE-mediated sensitization to flour allergens is widely used to investigate flour-induced occupational asthma. The diagnostic efficiency of detecting specific IgE antibodies (sIgEs) against wheat and rye flour, however, has not been thoroughly compared with other diagnostic procedures. OBJECTIVE: We sought to evaluate the diagnostic accuracy of sIgE against wheat and rye compared with specific inhalation challenge (SIC) with flour as the reference standard. METHODS: This retrospective multicenter study included 264 subjects who completed an SIC with flour in eight tertiary centers, of whom 205 subjects showed a positive SIC result. RESULTS: Compared with SIC, sIgE levels of 0.35 kUA/L or greater against wheat and rye provided similar sensitivities (84% to 85%, respectively), specificities (71% to 78%), positive predictive values (91% to 93%), and negative predictive values (56% to 61%). Increasing the threshold sIgE value to 5.10 kUA/L for wheat and to 6.20 kUA/L for rye provided a specificity of 95% or greater and further enhanced the positive predictive value to 98%. Among subjects with a positive SIC, those who failed to demonstrate sIgE against wheat and rye (n = 26) had significantly lower total serum IgE level and blood and sputum eosinophil counts and a lesser increase in postchallenge FeNO compared with subjects with a detectable sIgE. CONCLUSION: High levels of sIgE against wheat and/or rye flour strongly support a diagnosis of flour-induced occupational asthma without the need to perform an SIC. The absence of detectable sIgE against wheat and rye in subjects with a positive SIC seems to be associated with lower levels of TH2 biomarkers.

Novel IgE crosslinking-induced luciferase expression method using human-rat chimeric IgE receptor-carrying mast cells.

BACKGROUND: The measurement of antigen-specific serum IgE is common in clinical assessments of type I allergies. However, the interaction between antigens and IgE won't invariably trigger mast cell activation. We previously developed the IgE crosslinking-induced luciferase expression (EXiLE) method using the RS-ATL8 mast cell line; however, the method may not be sensitive enough in some cases. METHODS: In this study, we introduced an NF-AT-regulated luciferase reporter gene into the RBL-2H3 rat mast cell line and expressed a chimeric high-affinity IgE receptor (FcεRI) α chain gene, comprising an extracellular domain from humans and transmembrane/intracellular domains from rats. RESULTS: We generated multiple clones expressing the chimeric receptor. Based on their responsiveness and proliferation, we selected the HuRa-40 clone. This cell line exhibited significantly elevated human α chain expression compared to RS-ATL8 cells, demonstrating a 10-fold enhancement of antigen-specific reactivity. Reproducibility across different batches and operators was excellent. Moreover, we observed a detectable response inhibition by an anti-allergy drugs (omalizumab and cyclosporin A). CONCLUSIONS: HuRa-40 cells-which carry the human-rat chimeric IgE receptor-comprise a valuable reporter cell line for the EXiLE method. Their versatility extends to various applications and facilitates high-throughput screening of anti-allergy drugs.

Clinicomycological Study of the Spectrum of Pulmonary Aspergillosis at a Tertiary Care Hospital in Central India.

Knowing the spectrum, prevalence, and modes of diagnosis of pulmonary aspergillosis (PA) will be beneficial to clinicians for its early diagnosis and management. This study aims to estimate the prevalence, spectrum, and role of serological tests and radiological findings in the diagnosis of PA. A total of 150 patients were suspected of having PA after obtaining relevant clinical history and radiological imaging. The patients were grouped into each spectrum of PA as invasive PA (IPA), chronic necrotizing PA (CNPA), aspergilloma, allergic bronchopulmonary aspergillosis (ABPA) based on predisposing factors, clinical and radiological findings, and the guidelines of the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG). Samples (bronchoalveolar lavage (BAL), sputum, blood) were collected from these patients and processed in a microbiology lab. BAL and sputum were subjected to microscopy by potassium hydroxide mount, calcofluor white mount, and culture. The serum was separated from blood by centrifugation and subjected to specific serological tests based on the spectrum of PA that the patient was suspected to have. For IPA, serum and BAL galactomannan antigen enzyme-linked immunosorbent assay (ELISA) was performed. For CNPA and aspergilloma, the anti-Aspergillus IgG antibody ELISA was performed. For ABPA, the tests performed were total immunoglobulin E (IgE) ELISA, Aspergillus fumigatus-specific IgE ELISA, and anti-Aspergillus immunoglobulin G (IgG) antibody ELISA. After compiling the clinical, radiological, culture, and serological findings, patients were diagnosed to have a particular spectrum of PA. The prevalence of IPA was 1.4%, CNPA was 4%, ABPA was 3.2%, and aspergilloma was 2.9%. CNPA was the predominant spectrum of PA in our study. Culture positivity for Aspergillus species was seen the highest in aspergilloma patients, followed by IPA, ABPA, and CNPA patients. A. fumigatus was the most common causative agent of PA, except for IPA for which Aspergillus flavus was the most common causative. Aspergillus niger and Aspergillus terreus were less the frequent causes of PA. A combination of radiological, microbiological, and serological tests along with clinical correlation is needed to confirm the diagnosis of PA.

[Characterization of asthma phenotypes in children of the tropics]. / Caracterización de fenotipos de asma en niños del trópico.

OBJECTIVE: Determine the main asthma phenotypes in a population of asthmatic children in Cartagena, Colombia. METHODS: 107 children (7 to 17 years old) with a previous diagnosis of asthma were recruited. Biomarkers of T2 inflammation were evaluated by measuring FeNO, eosinophil count in peripheral blood by hemocytometry, and determination of specific IgE to mite allergens by ELISA. The study was approved by the ethics committee of the University of Cartagena (SGR, Grant BPIN2020000100405). RESULTS: The average age of patients was 10,9 years. 19,6% of the children did not show elevation of any of the T2 inflammation biomarkers evaluated (FeNO<20ppb, eos<300/ul, negative specific IgE), so they were considered patients with non-allergic asthma (non-T2). 71,9% of all patients were sensitized to at least one allergen, this phenotype was considered allergic asthma. 30,8% of the patients presented the three elevated biomarkers (FeNO>20ppb + eos >300/ul + positive specific IgE), this phenotype was classified as high T2 allergic asthma. A moderate correlation (Spearman rho=0,44, p<0,0001) was found between FeNO values and eosinophil counts. CONCLUSION: In this study, the following phenotypes were found: allergic asthma, high T2 asthma, and non-allergic asthma. Most patients presented a type 2 inflammatory phenotype with allergic sensitization. In addition to the measurement of specific IgE, the use of FeNO and eosinophil count in peripheral blood help to accurately determine those patients with high T2 asthma phenotypes.

OBJETIVO: Determinar los fenotipos principales de asma en una población de niños asmáticos en Cartagena, Colombia. MÉTODOS: Se reclutaron 107 niños (entre 7 y 17 años), con diagnóstico previo de asma. Se evaluaron biomarcadores de inflamación T2 mediante la medición de FeNO, conteo de eosinófilos en sangre periférica mediante hemocitometría, y la determinación de IgE específica a alergenos de ácaros mediante ELISA. El estudio fue aprobado por el Comité de Ëtica de la Universidad de Cartagena (SGR, Grant BPIN2020000100405). RESULTADOS: La edad media de los pacientes fue de 10,9 años. El 19,6% de los niños no mostró elevación de ninguno de los biomarcadores de inflamación T2 evaluados (FeNO<20 ppb, eos<300/ul, IgE específica negativa), por lo que se consideraron como pacientes con asma no alérgica (no-T2). El 71,9% de todos los pacientes estaban sensibilizados al menos a un alergeno considerándose este fenotipo como asma alérgica. El 30,8% de los pacientes presentaron los tres biomarcadores elevados (FeNO>20 ppb + eos >300/ul + IgE específica positiva), clasificando este fenotipo como asma alérgica T2 alta. Se encontró una correlación moderada (Spearman rho=0,44, p<0,0001) entre los valores de FeNO y los conteos de eosinófilos. CONCLUSIÓN: En este estudio se encontraron los siguientes fenotipos de asma alérgica: asma T2 alta y asma no alérgica. La mayoría de los pacientes presentó un fenotipo inflamatorio tipo 2 con sensibilización alérgica. Además de la medición de la IgE específica, el uso del FeNO y los conteos de eosinófilos en sangre periférica ayudan a determinar con mayor exactitud a aquellos pacientes con fenotipos de asma T2 alto.

A comparison of healthcare utilization and outcomes following skin vs. serum-specific IgE allergy testing.

OBJECTIVE: To compare the cost, healthcare utilization, and outcomes between skin and serum-specific IgE (sIgE) allergy testing. METHODS: This retrospective cohort study used IBM® MarketScan claims data, from which commercially insured individuals who initiated allergy testing between January 1 and December 31, 2018 with at least 12 months of enrollment data before and after index testing date were included. Cost of allergy testing per patient was estimated by testing pattern: skin only, sIgE only, or both. Multivariable linear regression was used to compare healthcare utilization and outcomes, including office visits, allergy and asthma-related prescriptions, and emergency department (ED) and urgent care (UC) visits between skin and sIgE testing at 1-year post testing (α = 0.05). RESULTS: The cohort included 168,862 patients, with a mean (SD) age of 30.8 (19.5) years; 100,666 (59.7%) were female. Over half of patients (56.4%, n = 95,179) had skin only testing, followed by 57,291 patients with sIgE only testing and 16,212 patients with both testing. The average cost of allergy testing per person in the first year was $430 (95% CI $426-433) in patients with skin only testing, $187 (95% CI $183-190) in patients with sIgE only testing, and $532 (95% CI $522-542) in patients with both testing. At 1-year follow-up post testing, there were slight increases in allergy and asthma-related prescriptions, and notable decreases in ED visits by 17.0-17.4% and in UC visits by 10.9-12.6% for all groups (all p < 0.01). Patients with sIgE-only testing had 3.2 fewer allergist/immunologist visits than patients with skin-only testing at 1-year follow-up (p < 0.001). Their healthcare utilization and outcomes were otherwise comparable. CONCLUSIONS: Allergy testing, regardless of the testing method used, is associated with decreases in ED and UC visits at 1-year follow-up. sIgE allergy testing is associated with lower testing cost and fewer allergist/immunologist visits, compared to skin testing.

NOVEOS and ImmunoCAP Have Similar Performances for Diagnosing Food Allergies.

BACKGROUND: The clinical significance of newly available platforms for specific IgE measurement must be evaluated. However, data are lacking for NOVEOS (Hycor), especially for food allergens. OBJECTIVE: We compared the technical and clinical performance of two platforms (ImmunoCAP and NOVEOS) to measure specific IgE to 10 food allergens. METHODS: Sera from 289 clinically characterized patients were tested for IgE specific for six food allergen extracts (egg white, cow's milk, peanut, hazelnut, fish, and shrimp) and four molecular allergens (Gal d 1, Bos d 8, Ara h 2, and Cor a 14). Specific IgE measurements were carried out using ImmunoCAP and NOVEOS methods. Food allergy diagnoses were established according to international guidelines. RESULTS: A strong correlation (ρ > 0.9) was present between the two platforms whereas specific IgE concentrations measured with NOVEOS were consistently lower (mean, -15%) than with ImmunoCAP. NOVEOS and ImmunoCAP provided similar overall odds ratios and relative risks for food allergy diagnosis with both allergen extracts and molecular allergens. When all 10 allergens were considered, NOVEOS provided better receiver operating characteristic curves (P = .04). Finally, we found that the most discordant results were observed with hazelnut and peanut extracts and were related to cross-reactive carbohydrate determinants for these two with ImmunoCAP. CONCLUSIONS: Specific IgE determination by either ImmunoCAP or NOVEOS (odds ratios of allergy, 25.1 or 33.0, respectively) is highly informative regarding the risk of allergy in the selected population. The NOVEOS platform presents the advantage of being less affected by unwanted reactivity owing to carbohydrate determinant-specific IgE while requiring a 10-fold lower test sample volume.

Comparison of intradermal and serum testing for environmental allergen-specific immunoglobulin E determination in a laboratory colony of cats with naturally acquired atopic syndrome.

BACKGROUND: Allergen testing is used to select antigens included in the desensitisation vaccine. Intradermal skin test (IDT) is the gold standard in cats, yet allergen-specific immunoglobulin (Ig)E serological testing (ASIS) is often used. Feline data are lacking regarding the agreement between IDT and ASIS results. HYPOTHESIS/OBJECTIVES: The first objective of the study was to establish a colony of cats with naturally acquired feline atopic syndrome (FAS). Further objectives were to define their hypersensitivity disorder to detail the allergen tests results, and to assess similarity between the allergen tests. ANIMALS: Thirty-five cats with FAS and 10 control cats. MATERIALS AND METHODS: Enrolled cats went through a five phase-screening and quarantine process before joining the colony. An elimination diet trial was performed on all FAS cats. ASIS and IDT were consecutively performed on all cats under sedation. RESULTS: Reactions to 34 allergens were compiled for the 45 cats. Global sensitivity and specificity of ASIS were 34.7% and 78.9%, respectively. Only flea (ICC = 0.26, p = 0.040) and Dermatophagoides pteronyssinus (ICC = 0.48, p < 0.001) allergens had a significant intraclass correlation (weak agreement). Two FAS cats had negative tests including one cat with a concomitant food allergy. CONCLUSIONS AND CLINICAL RELEVANCE: This study depicts the first reported colony of cats with naturally acquired FAS. This is the first feline study to compare and show the poor agreement between allergen tests with a panel of 34 allergens. This colony also harbours two cats with FAS with negative allergen tests. These may represent the first described cats with an intrinsic form of atopic syndrome.

Pediatric oral food challenges in the outpatient setting: A single-center experience.

Background: Oral food challenge (OFC) is the criterion standard for diagnosing food allergy (FA). It is important to have parameters to aid in selecting ideal OFC candidates. Objective: We sought to characterize outcomes and predictors of OFCs for common food allergens. Methods: We completed a retrospective chart review of all OFCs for IgE-mediated FA performed at Duke University pediatric allergy clinics from June 2017 through May 2022. Patients were deemed eligible for milk, egg, and nut OFC if testing revealed a specific IgE level not exceeding 2 kU/L and a skin prick test (SPT) resulting in a wheal size not exceeding 5 mm. Different parameters were followed for selecting candidates for baked challenge. Results: A total of 663 OFCs were conducted on 510 patients (59% male). The most common foods challenged were peanut (26%), plain egg (23%), baked egg (8%), and milk (8%), with pass rates of 84%, 88%, 62%, and 84%, respectively. Of the patients who failed OFC, 84% had objective symptoms, 23% had multisystemic reactions, and 15% required epinephrine. Although the presence of a personal or family history of atopy or prior failed OFC was not associated with outcomes, a history of anaphylaxis (regardless of the trigger) was associated with increased risk of failure. Conclusion: Although there are no established consensus guidelines, our study provides a benchmark illustrating that cutoffs of a specific IgE level not exceeding 2 kU/L and SPT finding not exceeding 5 mm result in a failure rate of approximately 13% for nonbaked milk, nonbaked egg, and nuts. The high rate of failed baked egg OFCs is likely related to selection bias, but our results illustrate the low negative predictive value of ovomucoid.