Diagnosis Of Allergy Research Articles

AllergoOncology: Biomarkers and refined classification for research in the allergy and glioma nexus-A joint EAACI-EANO position paper.

Epidemiological studies have explored the relationship between allergic diseases and cancer risk or prognosis in AllergoOncology. Some studies suggest an inverse association, but uncertainties remain, including in IgE-mediated diseases and glioma. Allergic disease stems from a Th2-biased immune response to allergens in predisposed atopic individuals. Allergic disorders vary in phenotype, genotype and endotype, affecting their pathophysiology. Beyond clinical manifestation and commonly used clinical markers, there is ongoing research to identify novel biomarkers for allergy diagnosis, monitoring, severity assessment and treatment. Gliomas, the most common and diverse brain tumours, have in parallel undergone changes in classification over time, with specific molecular biomarkers defining glioma subtypes. Gliomas exhibit a complex tumour-immune interphase and distinct immune microenvironment features. Immunotherapy and targeted therapy hold promise for primary brain tumour treatment, but require more specific and effective approaches. Animal studies indicate allergic airway inflammation may delay glioma progression. This collaborative European Academy of Allergy and Clinical Immunology (EAACI) and European Association of Neuro-Oncology (EANO) Position Paper summarizes recent advances and emerging biomarkers for refined allergy and adult-type diffuse glioma classification to inform future epidemiological and clinical studies. Future research is needed to enhance our understanding of immune-glioma interactions to ultimately improve patient prognosis and survival.

Psychosocial Impact of Food Allergy on Children and Adults and Practical Interventions.

IgE- and non-IgE-mediated food allergies are increasing in prevalence in children and adults worldwide. A food allergy diagnosis can be associated with a sense of overwhelm and stress and commonly has a negative impact on quality of life. While there is an increased recognition of the psychosocial effects of food allergy, the current research reflects the experience of mostly White, well-educated wealthier populations. Some studies have now explored the psychosocial impact among other populations; however, further study is needed. It is important that physicians and allied health professionals screen for the potentially negative psychosocial effects of food allergy and provide education to promote safety and self-efficacy at each visit; however, time may be a limiting factor. Numerous validated questionnaires are now available to help assess the psychosocial impact of food allergies. Allergy-friendly foods are typically more expensive, and thus, it is imperative that physicians screen for food insecurity as well. Educational resources should be offered regarding living well with food allergies at each visit. For patients and families experiencing anxiety or food allergy burden that is difficult to manage, referral to a mental health provider should be considered. Resources regarding programs to help accessing safe foods should also be available. Further research is needed among diverse populations focusing on interventions to best support patients and families with food allergy.

Beyond visual inspection: The value of infrared thermography in skin diseases, a scoping review.

Although warmth is a key sign of inflammatory skin lesions, an objective assessment and follow-up of the temperature changes are rarely done in dermatology. The recent availability of accurate, sensitive and cost-effective thermography devices has made the implementation of thermography in clinical settings feasible. The aim of this scoping review is to summarize the evidence around the value and pitfalls of infrared thermography (IRT) when used in the dermatology clinic. A systematic literature search was done for original articles using IRT in skin disorders. The results concerning the potential of IRT for diagnosis, severity staging and monitoring of skin diseases were collected. The data on the sensitivity and specificity of IRT were extracted. Numerous studies have investigated IRT in various skin diseases, revealing its significant value in wound management, skin infections (e.g. cellulitis), vascular abnormalities and deep skin inflammation (e.g. hidradenitis suppurativa). For other dermatological applications such as the interpretation of intradermal and patch allergy testing, hyper-/anhidrosis, erythromelalgia, cold urticaria and lymph node metastases more complex calculations, provocation tests or active cooling procedures are required. Dermatologists should be aware of a learning curve of IRT and recognize factors contributing to false positive and false negative results. Nonetheless, enough evidence is available to recommend IRT as a supplement to the clinical evaluation for the diagnosis, severity and follow-up of several skin diseases.

Predicting Penicillin Allergy: A United States Multicenter Retrospective Study

BackgroundUsing the reaction history in logistic regression and machine learning (ML) models to predict penicillin allergy has been reported based on non-United States (US) data. ObjectiveWe developed ML positive penicillin allergy testing prediction models from multi-site US data. MethodsRetrospective data from four US-based hospitals were grouped into four datasets: enriched training (1:3 case-control matched cohort), enriched testing, non-enriched internal testing, and non-enriched external testing. ML algorithms were used for model development. We determined area under the curve (AUC) and applied the Shapley Additive exPlanations (SHAP) framework to interpret risk drivers. ResultsOf 4,777 patients (mean age 60 [SD 17], 68% women, 91% White, 86% non-Hispanic) evaluated for penicillin allergy labels, 513 (11%) had positive penicillin allergy testing. Model input variables were frequently missing: immediate or delayed onset (71%), signs or symptoms (13%), and treatment (31%). The gradient boosted model was the strongest model with an AUC of 0.67 (95%CI 0.57-0.77), which improved to 0.87 (95%CI 0.73-1) when only cases with complete data were used. Top SHAP drivers for positive testing were reactions within the last year and reactions requiring medical attention; female sex and reaction of hives/urticaria were also positive drivers. ConclusionA ML prediction model for positive penicillin allergy skin testing using US-based retrospective data did not achieve performance strong enough for acceptance and adoption. The optimal ML prediction model for positive penicillin allergy testing was driven by time since reaction, seek medical attention, female sex, and hives/urticaria.

Correlation of Blomia tropicalis-specific immunoglobulin epsilon profiles with family history of atopy in a Filipino population.

House dust mites are the major source of indoor allergens in the tropical and subtropical regions with Blomia tropicalis (Bt) allergens as one of the leading causative agents of sensitization among patients from the tropics. Despite the clinical importance of Bt in various populations, its allergenicity remains unclear among Filipino allergic patients. This study determined the sensitization profiles of allergic Filipinos against Bt allergens and its correlation with atopy. Total immunoglobulin epsilon (IgE) (n = 960), Bt-specific IgE (n = 247), and Blomia tropicalis 5 (Blo t 5)-specific IgE (n = 87) profiles of allergic and nonallergic subjects were measured through enzyme-linked immunosorbent assay (ELISA). Point-biserial correlation coefficient was used to determine the association between Bt-specific IgE levels and selected demographics. Inhibition ELISA was performed to measure the inhibition capacity of recombinant Blo t 5 (rBlo t 5) against Bt allergen extracts. Mean total IgE levels of allergic cases (n = 171) were significantly higher (P < 0.001) compared to the mean IgE levels of nonallergic controls (n = 76). Among allergic subjects, 58% were sensitized to Blo t extract and 80% of which were sensitized to rBlo t 5 allergen. A positive correlation was observed between Bt-specific IgE and family history of atopic disease (P = 0.031). Inhibition assay revealed that 54% mean reactivity of 7 plasma samples was caused by rBlo t 5, validating that rBlo t 5 is a major allergen in Bt. This study has shown the importance of Bt as an allergen source that sensitizes atopic Filipino subjects. Hence, inclusion of Bt allergen extract and rBlo t 5 in the panel for allergy diagnosis and immunotherapy in Filipino populations is strongly recommended.

Bronchiectasis with Chronic Rhinosinusitis Is Associated with Eosinophilic Airway Inflammation and Is Distinct from Asthma.

Rationale: Bronchiectasis is an airway inflammatory disease that is frequently associated with chronic rhinosinusitis (CRS). An eosinophilic endotype of bronchiectasis has recently been described, but detailed testing to differentiate eosinophilic bronchiectasis from asthma has not been performed. Objectives: This prospective observational study aimed to test the hypotheses that bronchiectasis with CRS is enriched for the eosinophilic phenotype in comparison with bronchiectasis alone and that the eosinophilic bronchiectasis phenotype exists as a separate entity from bronchiectasis associated with asthma. Methods: People with idiopathic or postinfectious bronchiectasis were assessed for concomitant CRS. We excluded people with asthma or primary ciliary dyskinesia and smokers. We assessed sputum and blood cell counts, nasal NO and fractional excreted NO, methacholine reactivity, skin allergy testing and total and specific immunoglobulin (Ig) E, cytokines in the sputum and serum, and the microbiome in the sputum and nasopharynx. Results: A total of 22 people with CRS (BE + CRS) and 17 without CRS (BE - CRS) were included. Sex, age, Reiff score, and bronchiectasis severity were similar. Median sputum eosinophil percentages were 0% (IQR, 0-1.5%) in BE - CRS and 3% (1-12%) in BE + CRS (P = 0.012). Blood eosinophil counts were predictive of sputum eosinophilia (counts ⩾3%; area under the receiver operating characteristic curve, 0.68; 95% confidence interval, 0.50-0.85). Inclusion of CRS improved the prediction of sputum eosinophilia by blood eosinophil counts (area under the receiver operating characteristic curve, 0.79; 95% confidence interval, 0.65-0.94). Methacholine tests were negative in 85.7% of patients in the BE - CRS group and 85.2% of patients in the BE + CRS group (P > 0.99). Specific IgE and skin testing were similar between the groups, but total IgE levels were increased in people with increased sputum eosinophils. Microbiome analysis demonstrated distinct microbiota in nasopharyngeal and airway samples in the BE + CRS and BE - CRS groups, without significant differences between groups. However, interactome analysis revealed altered interactomes in individuals with high sputum eosinophil counts and CRS. Conclusions: Bronchiectasis with CRS is associated with an eosinophilic airway inflammation that is distinct from asthma.

Titanium Allergy: A Retrospective Review of 166 Patch Tested Patients.

Background: Although most patients do not develop hypersensitivity reactions to metals in implanted devices, when they do occur, significant morbidity can result. Titanium-based systems are often considered as an alternative option in metal-allergic patients; however, there are few studies published on titanium allergy and allergic reactions to titanium in implants may be overlooked in clinical practice. Methods: Our aim was to further characterize a single institution's experience with titanium patch testing and evaluation of titanium allergy. We performed a retrospective medical record review of 166 patients evaluated for titanium contact allergy between January 2018-August 2023. Of the 166 patients in our cohort, 67 were referred for pre-implant patch testing and 64 for post-implant patch testing; 35 were tested for reasons unrelated to an implant. Results: Twenty-six of the 166 patients were PTP to titanium (15.7% positive rate). Titanium PTP rates were higher for post-implant cases (28.1%, 18/64) compared to pre-implant cases (6.0%, 4/67) (χ2 9.97, p = 0.002). Among 18 titanium PTPs identified for the 64 post-implant cases, 8 were likely relevant, 8 possibly relevant, and 2 not likely relevant. Conclusions: Further studies should be performed to evaluate the incidence of allergy to titanium implants and to continue surveillance of changes in sensitization rates.

Allergic phenotype identified on allergen testing is associated with proton pump inhibitor nonresponse in eosinophilic esophagitis.

Food/environmental allergens have been associated with eosinophilic esophagitis (EoE); however, the correlation between allergy profiles and disease responsiveness to proton pump inhibitor (PPI) therapy remains unclear. We aimed to assess the association between food/environmental allergies identified on allergen testing and histologic response to PPI in patients with treatment-naive EoE. Adults with newly diagnosed EoE who underwent formal testing for food/environmental allergies at a tertiary center were included. All patients underwent twice-daily PPI for 8weeks with subsequent repeat endoscopy and biopsy to assess histologic response. Patients with <15 eosinophils/hpf on post-PPI mucosal biopsies were classified as responders (PPI-r-EoE), while those with ≥15 eosinophils/hpf were nonresponders (PPI-nr-EoE). Sixty-one patients met inclusion criteria (21 PPI-r-EoE vs 40 PPI-nr-EoE). Demographic, clinical, and endoscopic finding variables were similar between groups. Positive food allergen test was more prevalent among PPI-nr-EoE patients (82.5% vs 42.9%, P=0.003). On multivariable analysis, positive food allergen testing remained an independent predictor for PPI nonresponse (aOR 0.15, CI: 0.04-0.58, P=0.0006). Positive environmental allergen testing was highly prevalent, with no significant differences between groups (77.5% vs 95.2%, P=0.14). However, higher number of positive environmental allergens (23.3% [≥5 allergens] vs 73.3% [<5 allergens], P=0.003) and specific aeroallergens correlated with PPI-nr-EoE. Positive food allergy testing and increased environmental allergens predicted lower likelihood of histologic response to PPI in EoE. Our findings support an allergic phenotype of EoE that may less likely respond to PPI therapy. Formal allergen testing may play a role in therapy selection and tailored management in EoE.

Artificial intelligence-driven design of the assembled major cat allergen Fel d 1 to improve its spatial folding and IgE-reactivity

BackgroundCat-derived allergens are considered as one of the most common causes of allergic diseases worldwide. Fel d 1 is a major cat allergen and plays an important role in immunoglobulin E (IgE)-reaction diagnosis. However, the two separate chains of Fel d 1 exhibited lower IgE-reactivity than its complete molecule of an assembled form, which makes it difficult to efficiently prepare and limits the application of Fel d 1 in molecular diagnosis of cat allergy. MethodsWe first applied artificial intelligence (AI) based tool AlphaFold2 to build the 3-dimensional structures of Fel d 1 with different connection modes between two chains, which were evaluated by ERRAT program and were expressed in Escherichia coli. We then calculated the expression ratios of soluble form/inclusion bodies form of optimized Fel d 1. The Circular Dichroism (CD), High Performance Liquid Chromatography-Size Exclusion Chromatography (HPLC-SEC) and reducing/non-reducing SDS-PAGE were performed to characterize the folding status and dimerization of the optimized fusion Fel d 1. The improvement of specific-IgE reactivity to optimized fusion Fel d 1 was investigated by enzyme linked immunosorbent assay (ELISA). ResultsAmong several linkers, 2 × GGGGS got the highest scores, with an overall quality factor of 100. The error value of the residues around the junction of 2 × GGGGS was lower than others. It exhibited highest proportion of soluble protein than other Fel d 1 constructs with ERRAT (GGGGS, KK as well as direct fusion Fel d 1). The results of CD and HPLC-SEC showed the consistent folding and dimerization of two fused subunits between the optimized fusion Fel d 1 and previously well-defined direct fusion Fel d 1. The overall IgE-binding absorbance of optimized fusion Fel d 1 tested by ELISA was improved compared with that of the direct fusion Fel d 1. ConclusionWe firstly provided an AI-design strategy to optimize the Fel d 1, which could spontaneously fold into its native-like structure without additional refolding process or eukaryotic folding factors. The improved IgE-binding activity and simplified preparation method could greatly facilitate it to be a robust allergen material for molecular diagnosis of cat allergy.

Molecular diagnostic strategies and management of dust mite allergy

Dust mites are one of the most important allergens, widely distributed around the world, especially in household environments. Dermatophagoides pteronyssinus, Dermatophagoides farinae and Blomia tropicalis are the most common species of dust mites. There are more than 35 known sensitization components of dust mites, among which Der p 1, Der p 2 and Der p 23 are the major components. Clinically, allergen skin test and serum specific immunoglobulin E (sIgE) detection are widely used in the preliminary diagnosis of dust mite allergy. However, these methods cannot accurately identify specific dust mite sensitization components. Considering that there are significant differences in the allergenic components of dust mites in different regions and populations, component-resolved diagnosis of dust mite is particularly important in accurately determining the allergenic components. This is not only of guiding significance for allergen avoidance, but also important for determining the immunotherapy regimen for dust mites. In order to strengthen the understanding of the molecular diagnosis of dust mites and promote the integration of allergy science in China with the international standards, this article interprets the "Allergy Molecular Allergology User's Guide 2.0" published recently by the European Academy of Allergy and Clinical Immunology.

Challenges in Drug and Hymenoptera Venom Hypersensitivity Diagnosis and Management in Mastocytosis.

Mastocytosis is a myeloproliferative neoplasm characterized by abnormal proliferation and activation of clonal mast cells typically bearing the KITD816V mutation. Symptoms manifest due to the release of bioactive mediators and the tissue infiltration by neoplastic mast cells. Mast cell activation symptoms include flushing, pruritus, urticaria, abdominal cramping, diarrhea, wheezing, neuropsychiatric symptoms, and anaphylaxis. Up to 50% of patients with mastocytosis report a history of provoked and unprovoked anaphylaxis, with Hymenoptera venom and drugs the most common culprits. NSAIDs, antibiotics, vaccines, perioperative medications, and radiocontrast media are often empirically avoided without evidence of reactions, depriving patients of needed medications and placing them at risk for unfavorable outcomes. The purpose of this review is to highlight the most common agents responsible for adverse drug reactions in patients with mastocytosis, with a review of current epidemiology, diagnosis, and management of drug hypersensitivity and Hymenoptera venom allergy.

Pollen food allergy syndrome secondary to molds and raw mushroom cross-reactivity: a case report

BackgroundPollen food allergy syndrome (PFAS) is an immunoglobulin E (IgE) mediated reaction that causes oropharyngeal pruritus or angioedema due to homologous proteins present in the culprit food as well as a sensitizing aeroallergen. This cross-reactivity has been well established between pollen and fruits/vegetables. Given the evolutionary similarity between all fungi; cross-reactivity between spore forming microfungi and edible macrofungi have been suggested, however only a limited number of case reports have ever been published on this phenomenon. We present a case of a patient who experiences pollen food allergy syndrome-like symptoms following lightly cooked mushroom ingestion who otherwise was able to tolerate cooked mushrooms. We then review the literature to highlight the limited studies of an underrecognized PFAS cross-reactivity between molds and mushrooms.Case presentationA 15-year-old male presents with symptoms of seasonal and perennial allergic rhinitis was found to have multiple environmental sensitizations to molds via skin prick testing (C.gramineum, A.Pullulans and B.cinerea) and ImmunoCAP serum-specific IgE (A.alternata, C. herbarum, and P. notatum). He developed throat pruritus and subjective throat tightness following ingestion of mushroom containing pizza. ImmunoCAP serum specific IgE to whole mushroom was negative but fresh food prick testing to fresh portobello mushroom and cremini mushroom were both positive with a negative test to canned mushroom. The patient then underwent a graded oral challenge and successfully tolerated canned mushrooms.ConclusionThis case highlights the potential cross-reactivity between microfungi aeroallergens and edible fungi, leading to PFAS-like reactions in susceptible individuals. The patient’s ability to tolerate canned mushrooms suggests a possible heat-labile protein as the cause of the reaction, similar to PFAS patients tolerating cooked but not raw fruits/vegetables. Positive skin prick test to both spore-forming fungi and edible fungi with negative and whole mushroom IgE results further support the hypothesis of cross-reactivity and sensitization. Further research is needed to identify the specific allergenic proteins involved in these cross-reactions and the susceptible species of mold and mushroom. Understanding these components will contribute to improved diagnosis and management of mold and mushroom allergies, and enhance our knowledge of allergenic cross-reactivity in general.

P06 Outcomes from a New Combined Allergy and Dermatology Clinic- A Retrospective Review

Abstract Early introduction to known allergens such as peanuts can reduce subsequent development of allergies [1]. In 2019, an audit in our department of 35 babies under age 1 referred with eczema showed that 4 were concomitantly referred to allergy and 20 were referred to allergy after dermatology consultation. The majority had moderate/severe eczema and 31% had implemented dietary restrictions before the dermatology consultation. In 2021, a combined allergy and dermatology clinic was introduced to provide a holistic approach, particularly for young children. Patients are triaged from GP referrals or as follow-up from either team. We conducted a retrospective notes review to explore the benefits/outcomes. 57 patients were included with an average age of 4.75 years and 58% were below age 2. 58% had their dermatology plans changed. Before the clinic, 81% had dietary exclusions but only 46% had new allergies confirmed. 29% of the patients who underwent testing tested negative to all allergens, which allowed parents to reintroduce foods at an early age. This review shows that the combined clinic allowed young patients early access to allergy testing due to streamlined services, preventing unnecessary dietary exclusions. Additionally, patients with severe eczema without allergies benefit from early dermatology intervention. In fact, 44% of patients were suitable for discharge from dermatology directly from the combined clinic or at first follow-up appointment.

Systemic Reactions to Skin Prick Test with Food Allergens in Children.

Although skin prick tests (SPTs) are generally considered safe, limited studies have specifically evaluated reactions related to SPTs with all allergens. In contrast to these studies, our aim is to exclusively evaluate systemic reaction (SR) occurrences with food allergens during SPTs in children. All patients who underwent skin prick and/or prick-to-prick (PtoP) tests with food allergens at our clinic between January 2010 and January 2020 were included in the study. The occurrence of SR during SPTs was evaluated based on patient records. The study included 1852 patients, with 57% males and a median age of 31 months (1-210). Skin tests were most commonly conducted for the indication of atopic dermatitis (29.3%). During the study, 11.2% had repeat SPTs for tolerance and a new allergy diagnosis. No local reactions or SRs occurred during SPTs. Among those with PtoP tests, 3 patients (0.16%) experienced SRs-1 had anaphylaxis (0.05%), the rest had angioedema. Legumes and sea bass caused these reactions. In patients with severe index reactions and those who underwent PtoP testing, SR development was significantly higher (P < .001 for both), and anaphylaxis occurrence was significantly higher among those undergoing PtoP testing compared to prick testing alone (P = .03). The prevalence of both SR and anaphylaxis due to SPT with food allergens was found to be quite low in children. However, it is important to consider the possibility of SR development before conducting SPT with food allergens, especially in patients who will undergo the PtoP test and those with severe index reactions. Cite this article as: Karkın G, Ertoy Karagol Hİ, Polat Terece S, Köken G, Yapar D, Bakırtaş A. Systemic reactions to skin prick test with food allergens in children. Turk Arch Pediatr. 2024;59(1):54-59.

Expert consensus on diagnosis and management of neonatal cow's milk protein allergy (2023)

Expert consensus on diagnosis and management of neonatal cow's milk protein allergy (2023)

The role of pediatricians in the diagnosis and management of IgE-mediated food allergy: a review.

Food allergy can often cause a significant burden on patients, families, and healthcare systems. The complexity of food allergy management requires a multidisciplinary approach involving different types of healthcare providers, including allergists, dieticians, psychologists, nurses, family practitioners and, of particular relevance for this article, pediatric primary caretakers. Pediatricians may be the first-line healthcare providers for food allergy: strategies for management and guideline adherence have been highlighted. This review article summarizes the up-to-date recommendations on the role of pediatricians in the diagnosis, management, and prevention of IgE-mediated food allergy. Early introduction of allergenic foods like peanut is known to be of importance to reduce the development of peanut allergy in infants, and pediatricians are essential for educating and supporting parents in this decision. In scenarios of limited allergist availability, as is often the case among rural, Medicaid and minority populations, pediatricians can assist in the evaluation and management of food allergy, and provide action plans, education and counselling for patients and families. Pediatric primary caretakers play a key role in the diagnosis, management, and prevention of IgE-mediated food allergy. As more diagnostic tools and therapies in food allergy become available, the need for a multidisciplinary team is paramount to optimize patient care.

Human umbilical cord mesenchymal stem cells toxicity and allergy effects: In vivo assessment.

Human umbilical cord mesenchymal stem cells (hUCMSCs) hold significant promise across various clinical applications. Therefore, regulatory requirements necessitate a thorough investigation of the hUCMSCs safety before clinical trials and potential allergic reactions after transplantation. Abnormal toxicity test employed mice and guinea pigs dosed daily at 0.5×106 cells and 5×106 cells, respectively for 7 days. Acute toxicity test employed low, medium, and high doses of hUCMSCs injected into mice once, followed by observations for 23 days. In systemic allergy test, guinea pigs received low and high dose of hUCMSCs, with sensitization and excitation stages at day 14 and 21, respectively. The abnormal toxicity test of hUCMSC injections revealed no abnormal reactions over a seven-day observation period, indicating the safety of this administration route. In acute toxicity studies, the high-dose hUCMSCs group resulted in fatalities due to pulmonary embolism. Conversely, the low-dose group exhibited no toxic reactions or deaths. The maximum tolerated dose was determined to be >2×107 cells/kg. Systemic active allergy test showed that high doses of hUCMSC intravenous injections did not induce allergic reactions. This research affirms hUCMSC injections meet safety standards for clinical cell therapy, emphasizing their safe and promising clinical utility.

Agreement of Peru-Based Allergy Tests for Respiratory Allergens in Allergic Rhinitis Patients.

The Peruvian Immunoblot panel, together with traditional skin prick tests (SPT), are widely used in vitro allergy tests in Peru. In addition to this, Peruvian allergists are increasingly adopting multiplex tests such as the ALEX-2 (Macro Array Diagnostics). Previous studies have revealed limited agreement between Immunoblot and SPT results. Therefore, our study aimed to evaluate the concordance between these three tests in patients with allergic rhinitis (AR) in a private center in Arequipa, Peru. We enrolled 35 patients, including children over 3 years and adults, with AR. Clinical and demographic data were collected, and patients underwent allergic sensitization testing using the Immunoblot Peruvian panel (32 allergens), ALEX-2 (295 allergens), and SPT (12 allergens). Concordance was calculated using Cohen's kappa coefficient and analyzed with IBM SPSS V26. Among the patients, 34.3% exhibited moderate-to-severe persistent AR, and 14.3% had asthma. Additionally, 85.7% reported a family history of AR. Sensitization rates varied notably between the SPT and ALEX-2, particularly for olive pollen (34.3% vs. 17.4%), Blomia tropicalis (11.4% vs. 17.1%), and grasses (11.4% vs. 28.5%). Remarkably, these allergens were not included in the Peruvian Immunoblot panel. Concordance analysis included seven allergens and showed significant concordance between ALEX-2 and SPT for five allergens, between Immunoblot and SPT for two allergens, and between ALEX-2 and Immunoblot for two allergens. This preliminary study shows us a better concordance between ALEX-2 and SPT rather than between Immunoblot and SPT.

Gastrointestinal-isolated Distress is Common in Alpha-gal Allergic Patients on Mammalian Meat Challenge.

Alpha-gal allergy causes a delayed reaction to mammalian meats and has been reported worldwide. Patients with the allergy may present with isolated gastrointestinal (GI) symptoms, but this phenotype is poorly understood. We pooled and analyzed symptoms and demographics of patients from two prospective cohorts of patients with a diagnosis of alpha-gal allergy who reacted after eating mammalian meat under observation. We compared the characteristics of patients who demonstrated GI-isolated symptoms on a challenge with those who exhibited symptoms outside the GI tract (skin, respiratory, and circulatory). Among the 91 children and adult alpha-gal allergic patients who exhibited symptoms after oral challenge with mammalian meat, 72.5% experienced GI distress with one or more GI symptoms, which was the most frequent class of symptoms, compared with skin changes in 57.1% and respiratory distress in 5.5%. The most common GI symptoms were abdominal pain (71%) and vomiting (22.0%). GI-isolated symptoms occurred in 37 patients (40.7%) who reacted, and those patients reacted more quickly than patients who exhibited systemic symptoms (median onset of symptoms in GI-isolated group 90 min vs 120 min) and were more likely to be children than adults (relative risk=1.94, 95% CI: 1.04-3.63). Isolated-GI distress occurred in 4 in every 10 alpha-gal allergic individuals who developed symptoms on oral food challenge with mammalian meat. Alpha-gal allergic patients, particularly children, may exhibit GI distress alone, and adult and pediatric gastroenterologists should be aware of the diagnosis and management of the allergy.

Eliciting and stop dose during oral food challenges for peanut and common tree nuts in different age groups.

Oral food challenges (OFCs) are used to confirm or reject a diagnosis of food allergy. However, younger children may encounter difficulties in consuming all offered doses during an OFC in the absence of symptoms, resulting in inconclusive outcomes. Our aim is to assess the eliciting dose for objective symptoms among various age groups and determine the necessity of consuming the final dose step during an uneventful OFC to avoid false negative outcomes. OFCs for common food allergens performed between 2012 and 2019 were analyzed retrospectively. The primary outcome was the association of age with stop dose for OFCs with inconclusive outcome. Secondary outcome measures were the association of age with eliciting dose and the potential number of false negative outcomes. A total of 1327 OFCs were performed in 707 patients. Of these, 514 (38.7%) were positive, 589 (44.4%) negative, and 224 (16.9%) inconclusive. In OFCs with inconclusive outcome, age appeared to be a significant predictor of the stop dose only for almond (p = .005). Objective symptoms occurred after the last dose step in 2%-13% of all OFCs with positive outcome. In our cohort, potential false negative outcomes may have been drawn in 27.6% of uneventful OFCs. Two third of children under 6 years of age successfully consumed all the provided doses during OFCs with a negative outcome. The eliciting dose for objective symptoms was not associated with age, and in a substantial number of OFCs with positive outcome, symptoms occurred after eating the final dose. These findings suggest that in case of an uneventful OFC, the outcome should be drawn only after a cumulative dose of 4.4 g has been consumed to avoid the risk of a potential false negative outcome.