Alergológica 2015: A National Survey on Allergic Diseases in the Spanish Pediatric Population

Tolerance of peanuts and tree nuts in Spanish children with exclusive sensitization to lipid transfer proteins

BACKGROUND

Allergy to peanuts and tree nuts is a common cause of food allergy in Spain, with lipid transfer proteins (LTP) being the most frequently recognized panallergen. LTP sensitization often leads to multiple food group sensitivities, resulting in overly restrictive diets that hinder patient's quality of life. This study aimed to assess the tolerance of peanuts and tree nuts (hazelnuts and walnuts) in children sensitized to LTP, potentially mitigating the need for such diets.

METHODS

This prospective study enrolled individuals diagnosed with allergy to peanuts, hazelnuts, or walnuts. Data were collected from medical records, including demographics and clinical history. Allergological assessment comprised skin prick tests using commercial extracts and the nuts in question, alongside measurements of total and specific IgE to nuts and their primary molecular components. Participants showing positive LTP sensitization without sensitization to seed storage proteins underwent open oral nut challenges.

RESULTS

A total of 75 individuals labeled as allergic to peanuts, 44 to hazelnuts, and 51 to walnuts were included. All of them underwent an open oral provocation test with the incriminated nut, showing a high tolerance rate. Peanut was tolerated by 98.6% of patients, 97.72% tolerated hazelnut, and 84.3% tolerated walnut.

CONCLUSION

The findings suggest that the majority of patients allergic to peanuts, hazelnuts, or walnuts, due to LTP sensitization and lacking IgE reactivity to seed storage proteins, can tolerate these nuts. This supports the need for personalized nut tolerance assessments to avoid unnecessary dietary restrictions.

Involvement of autologous myeloid dendritic cells in the evaluation of immediate hypersensitivity reactions to betalactams

BACKGROUND

Amoxicillin (AX) and clavulanic acid (CLV) are the betalactam antibiotics (BLs) most used to treat bacterial infections, although they can trigger immediate hypersensitivity reactions (IDHRs). The maturation analysis of monocyte-derived dendritic cells (moDCs) and their capacity to induce proliferative response of lymphocytes are useful to test the sensitisation to a drug, although without optimal sensitivity. Nevertheless, this can be improved using directly isolated DCs such as myeloid DCs (mDCs).

METHODS

mDCs and moDCs were obtained from 28 allergic patients (AP), 14 to AX, 14 to CLV and from 10 healthy controls (HC). The expression of CCR7, CD40, CD80, CD83, and CD86 was analysed after stimulation with both BLs. We measured the capacity of these pre-primed DCs to induce drug-specific activation of different lymphocyte subpopulations, CD3+, CD4+, CD8+, CD4+Th1, and CD4+Th2, by flow cytometry.

RESULTS

Higher expression of CCR7, CD40, CD80, CD83, and CD86 was observed on mDCs compared to moDCs from AP after stimulating with the culprit BL. Similarly, mDCs induced higher proliferative response, mainly of CD4+Th2 cells, compared to moDCs, reaching up to 67% of positive results with AX, whereas of only 25% with CLV.

CONCLUSIONS

mDCs from selective AP efficiently recognise the culprit drug which trigger the IDHR. mDCs also trigger proliferation of lymphocytes, mainly those with a Th2 cytokine pattern, although these responses depend on the nature of the drug, mimicking the patient's reaction.

Direct oral challenge for immediate and non-immediate beta-lactam allergy in children: A real-world multicenter study

BACKGROUND

Allergy to beta-lactam antibiotics (BLA) is frequently suspected in children, but a drug provocation test (DPT) rules it out in over 90% of cases. Direct oral DPT (DODPT), without skin or other previous tests, is increasingly been used to delabel non-immediate BLA reactions. This real-world study aimed to assess the safety and effectiveness of DODPT in children with immediate and non-immediate reactions to BLAs.

METHODS

Ambispective registry study in children (<15 years), attended between 2016 and 2023 for suspected BLA allergy in 15 hospitals in Spain that routinely perform DODPT.

RESULTS

The study included 2133 patients with generally mild reactions (anaphylaxis 0.7%). Drug provocation test with the implicated BLA was performed in 2014 patients (94.4%): 1854 underwent DODPT (86.9%, including 172 patients with immediate reactions). One hundred forty-five (7.2%) had symptoms associated with DPT, although only four reactions were severe: two episodes of anaphylaxis and two of drug-induced enterocolitis syndrome, which resolved rapidly with treatment. Of the 141 patients with mild reactions in the first DPT, a second DPT was considered in 87 and performed in 57, with 52 tolerating it without symptoms. Finally, BLA allergy was ruled out in 90.9% of the sample, confirmed in 3.4%, and remained unverified, usually due to loss to follow-up, in 5.8%.

CONCLUSIONS

Direct oral DPT is a safe, effective procedure even in immediate mild reactions to BLA. Many reactions observed in DPT are doubtful and require confirmation. Severe reactions are exceptional and amenable to treatment. Direct oral DPT can be considered for BLA allergy delabeling in pediatric primary care.

Plant-based beverages as milk alternatives? Nutritional and functional approach through food labelling

Plant-based beverages (PBB) market is largely growing. In this study, 136 beverages made of soy, oat, almond, rice, tigernut, and others (mixtures of various plant materials), from the Spanish market were evaluated through labelling information. Energy value and fat content were intermediate between skimmed and whole cow milk; while fatty acids profile was quite different. Carbohydrate content was usually higher than cow milk, and highly dependent on the addition of sugars. All products provided some dietary fibre. With the exception of soy-based drinks, samples presented lower protein and calcium content than milk (1/3 samples studied were Ca-fortified), and 23% were vitamin D enriched. The claim "No added sugars" was in more than 50% samples. A right labelling and nutritional education of consumers is essential to make adequate choices, since the appearing of many claims is not always indicative of a better-quality product. Plant-based beverages cannot be considered as an alternative to milk, but as a different product, with their own nutritional and functional entity. Their inclusion in a diversified balanced diet can provide interesting functional components, such as soluble fibre or unsaturated fatty acids (mainly soybean and almond drink), which can help improve the health status of the population.

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Shared Decision-Making in Allergen Immunotherapy (AIT) Options Using a Questionnaire for Respiratory Allergic Patients: A Delphi Consensus Study

Purpose

The objective of this study was to develop and validate a questionnaire, through a Delphi consensus, to be used by allergists in their routine clinical practice to assess the preferences of patients starting allergen immunotherapy (AIT) treatment using an objective approach.

Patients and Methods

A Delphi consensus-driven process was used. The scientific committee, composed of 15 allergists, led the study and participated in the preparation of the questionnaire. Two-hundred panelists from different Spanish regions were invited to complete a 16-item questionnaire on a nine-point Likert scale covering six topic blocks. Consensus was achieved if ≥66.6% of panelists reached agreement or disagreement.

Results

Of the 200 experts invited to participate in the Delphi process, a total of 195 (97.5%) answered the questionnaire. The panel experts reached a consensus on "agreement" on a total of 12 of the 16 (75.0%) items, covering a total of six categories: (a) patient knowledge (2 questions), (b) barriers to patient adherence (3 questions), (c) patient behavior (4 questions), (d) future actions (3 questions), (e) treatment costs (2 questions), and (f) final patient preferences (2 questions).

Conclusion

This Delphi consensus study validated a set of twelve recommended questions for patients objectively assessing their preferences and suitability for the most common AIT options available. The questionnaire intends to assist allergists in making an objective, unconditioned decision regarding the best AIT option for each patient, after informing them about the different routes.

Efficacy of subcutaneous house dust mite immunotherapy in patients with moderate to severe allergic rhinitis

Aim: To evaluate the efficacy of subcutaneous immunotherapy (SCIT) for the treatment of allergy to house dust mites (HDM) in adults with moderate/severe allergic rhinitis (AR). Methods: Patients sensitized to HDM were randomized to SCIT plus rescue medication (Group A, n = 38) or rescue medication alone (Group B, n = 18), and assessed at baseline and 2, 6 and 12 months. Results: At month 12, Group A presented significant improvement with respect to baseline as evaluated by a visual analogue scale at three concentrations of antigen (0.1, 1 and 10 IR/ml; p < 0.0001). Group A presented significant decreases in symptom scores after 2 months of treatment, which were maintained after 1 year. After 12 months of treatment, Group A showed rescue medication consumption reductions (p < 0.001) and quality of life improvements (p < 0.0001). SCIT elicited a strong immunological response and was well tolerated. Conclusion: SCIT is efficacious for HDM allergy in patients with AR, generating a strong immunological response. Trial Registration Number: EUCTR2009-018155-16-ES (Cochrane Central Register of Controlled Trials).

Advances and highlights in T and B cell responses to drug antigens

The immunological mechanisms involved in drug hypersensitivity reactions (DHRs) are complex, and despite important advances, multiple aspects remain poorly understood. These not fully known aspects are mainly related to the factors that drive towards either a tolerant or a hypersensitivity response and specifically regarding the role of B and T cells. In this review, we focus on recent findings on this knowledge area within the last 2 years. We highlight new evidences of covalent and non-covalent interactions of drug antigen with proteins, as well as the very first characterization of naturally processed flucloxacillin-haptenated human leukocyte antigen (HLA) ligands. Moreover, we have analysed new insights into the identification of risk factors associated with the development of DHRs, such as the role of oxidative metabolism of drugs in the activation of the immune system and the discovery of new associations between DHRs and HLA variants. Finally, evidence of IgG-mediated anaphylaxis in humans and the involvement of specific subpopulations of effector cells associated with different clinical entities are also topics explored in this review. All these recent findings are relevant for the underlying pathology mechanisms and advance the field towards a more precise diagnosis, management and treatment approach for DHRs.

Preference for sublingual immunotherapy with tablets in a Spanish population with allergic rhinitis

BACKGROUND

This study investigated patients' preference for allergy immunotherapy (AIT) administered as either sublingual immunotherapy-tablets versus monthly or weekly subcutaneous immunotherapy (SCIT) from a Spanish patient perspective.

METHODS

A discrete choice experiment (DCE) consisting of two blocks with eight choice sets in each was constructed to elicit the preferences for AIT. Three attributes were included in the DCE for the mode of administration, including the frequency of administration, the risk of systemic reactions and the co-payment. Adults and caregivers of children with moderate to severe allergic rhinitis (AR) were included if they were not currently receiving or had not previously received AIT.

RESULTS

In total, 587 adults and 613 caregivers started the survey. Of those, 579 adults and 611 caregivers completed the survey and were included in the study. Both adults and caregivers had a significant preference for tablets compared with both monthly and weekly injections (p ≤ 0.0001). Furthermore, the respondents showed a significant preference for reducing the risk of systemic reactions. Subgroup analyses showed that caregivers of polyallergic children and female caregivers were significantly less price sensitive when choosing their preferred treatment.

CONCLUSION

Our study demonstrated that both adults with AR and caregivers of children with AR prefer daily SLIT-tablets to SCIT with either a weekly or monthly dose schedule.

Storage Proteins Are Driving Pediatric Hazelnut Allergy in a Lipid Transfer Protein-Rich Area

Oral food challenge (OFC) remains the gold standard for the diagnosis of food allergies. However, this test is not without risks, given that severe allergic reactions can be triggered while it is conducted. The purpose of this study is to identify potential demographic variables, clinical characteristics of the patients and biomarkers that may be associated with severe reactions during the hazelnut oral challenge test. The sample included 22 children allergic to hazelnut who underwent a tree nut skin prick test (SPT), specific IgE (sIgE) to hazelnut, component-resolved diagnosis (CRD) with different hazelnut allergens (Cor a 1, Cor a 8, Cor a 9, Cor a 11, Cor a 14), and a single-blind placebo-controlled challenge with hazelnut. A statistically significant relationship was found between the severity of the reaction and the highest values of sIgE to hazelnut, Cor a 11 and Cor a 14, cumulative symptom-triggering dose and sunflower seed sensitization. The use of the CRD is a useful tool to identify patients at higher risk of developing a severe reaction. In this pediatric population sample from Spain, storage proteins were confirmed to be most involved in hazelnut allergy and the development of severe reactions.

Systematic evaluation of allergic phenotypes of rhinitis in children and adolescents

BACKGROUND

Three allergic phenotypes of rhinitis have been described in adults: allergic rhinitis (AR), local allergic rhinitis (LAR), and dual allergic rhinitis (DAR, coexistence of AR and LAR). Nevertheless, most centers follow a diagnostic approach only based on skin prick test and serum allergen-specific IgE (collectively called atopy tests, AT). This approach prevents the recognition of LAR and DAR, the diagnosis of which requires a nasal allergen challenge (NAC). Here, we investigate the existence of LAR and DAR phenotypes in children and adolescents, and the misdiagnosis rate associated with a work-up exclusively based on AT.

METHODS

Clinical data were obtained during physician-conducted interviews, and AT and NAC were systematically performed in 5- to 18-year-old patients with chronic rhinitis. The misdiagnosis rate was defined as the proportion of cases where AT and NAC results were discordant.

RESULTS

A total of 173 patients (mean age 15.1 years, 39.9% male) completed the study. AR (positive AT and NAC), LAR (negative AT and positive NAC), DAR (positive AT and NAC for some allergens and negative AT and positive NAC for other allergens), and non-allergic rhinitis (negative NAC) were diagnosed in 45.7%, 24.9%, 11.6%, and 17.9% of individuals, respectively. The clinical profile was comparable among allergic phenotypes, but allergic patients had a significantly earlier rhinitis onset, higher conjunctivitis prevalence, and more severe disease than NAR individuals. A diagnostic work-up exclusively based on AT misclassified 37.6% of patients.

CONCLUSIONS

LAR and DAR represent relevant differential diagnosis in pediatric rhinitis. NAC increases the diagnostic accuracy of clinical algorithms for rhinitis in children and adolescents.

Changes in epidemiology and clinical practice in IgE-mediated Allergy in children

In the last decades, allergic diseases have increased exponentially and although pediatric asthma prevalence is stabilizing, it is estimated around 10% in Spain. Not the same with food allergy and anaphylaxis which are clearly increasing, becoming a significant public health problem. Taking into account epidemiological trends, the European Academy of Allergy and Clinical Immunology (EAACI) estimates that in less than 15 years more than half of the European population will suffer from some type of allergic disorder. The advances in diagnostic methods in food allergy, especially component resolved diagnosis, allow us to know the patient's sensitization profile and explain possible cross reactivity, anticipate potential risk of food trangressions, and prescribe correct avoidance diet in each patient. Thus, the development of molecular biology and nanotechnology have led to the appearance of new technologies (microarrays) which facilitate the study, specially of the polysensitized patients, allowing allergen immunotherapy (AIT) to be more personalized. The latest advances in the use of biologics are having an impact, not only in disease evolution, but also in quality of life.

[Changes in epidemiology and clinical practice in IgE-mediated allergy in children]

In the last decades, allergic diseases have increased exponentially and although pediatric asthma prevalence is stabilizing, in Spain is estimated around 10%. Not the same with food allergy and anaphylaxis which are clearly increasing, becoming a public health problem of the first magnitude. Considering epidemiological trends, the European Academy of Allergy and Clinical Immunology (EAACI) estimates that in less than 15 years more than half of European population will suffer from some type of allergy. The advances in diagnostic methods in food allergy, especially component resolved diagnosis, allow us to know the patient's sensitization profile and explain the possible cross reactivity, anticipate potential risk of food transgressions, and prescribe the correct avoidance diet in each patient. Thus, the development of molecular biology and nanotechnology have led to the appearance of new technologies (microarrays) which facilitate the study, specially of the polysensitized patients, allowing allergen immunotherapy (AIT) to be more personalized. The latest advances in the use of biologics are having an impact, not only in disease evolution, but also in patients quality of life.

Predicting health-related quality of life in Spanish adolescents with allergic rhinoconjunctivitis and bronchial asthma

This study analyzed the predictive power of sociodemographic (age, sex) and medical variables (months since diagnosis and in treatment, immunotherapy, number of environmental allergens, food allergies or atopic dermatitistypes) on the quality of life of patients with rhinoconjunctivitis and bronchial asthma, using models based on comparative qualitative fuzzy analysis to compare them according to the pathology(s).Retrospective cross-sectional design.Sixty-four adolescents (65.60% boys) diagnosed with rhinoconjunctivitis and/or bronchial asthma aged between 12 and 16 years old (M= 14.02; SD = 1.45).The data were collected between February 2019 and January 2020 using the Brief Disease Perception Questionnaire (B-IPQ), the Adolescent Rhinoconjunctivitis Quality of Life Questionnaire (AdolRQoLQ) and the Respiratory Disease Questionnaire Self-administered and Standardized Chronicle (CRQ-SAS). Qualitative comparative analysis models (QCA) were used.In the QCA models, the various combinations indicated that the variables that predicted a higher quality of life for both rhinocojuntivitis symptoms and respiratory symptoms were receiving longer-term immunotherapy and a perceived lower threat of the disease. The consistencies of the models vary between 23-29%. In conclusion, the patients' QoL was explained by the presence of longer-term immunotherapy and a less threatening perception of the disease.Therefore, early multidisciplinary diagnosis and treatment is important.

Cross-cultural adaptation of the sinus and nasal quality of life survey (SN-5) to Spanish

OBJECTIVE

There is a high prevalence for rhinitis with an increasing trend. However, there is a lack of specific quality of life pediatric questionnaires for sinonasal symptoms. The Sinus and Nasal Quality of Life Survey (SN-5) is the only validated instrument specifically designed with this objective. In this work we have translated and validated the Spanish version of the SN5 questionnaire.

METHODS

The SN5 was translated according to the World Health Organization recommendation for the translation and adaptation of instruments. The final version of the Sp-SN5 was administered twice (day 0 and day 7) to 137 participants with and without sinonasal symptoms. Reliability was measured with Cronbach α, temporal stability was measured with intraclass correlation coefficient. External validity was assessed with a ROC curve comparing a cohort of cases (children going to turbinate radiofrequency ablation) and controls (asymptomatic children).

RESULTS

A Spearman correlation between the total result of the Sp-SN-5 questionnaire and the QOL score showed a strong negative correlation in the general sample and all the age subgroups. Internal consistency measured with Cronbach α was 0.87 for 5 items and was still over 0.83 after removing each item of the test. The intraclass correlation coefficient (ICC) for test-retest measurements was 0.94. The receiver operating characteristic (ROC) curve for all the included participants showed a very high area under the curve (0.998).

CONCLUSIONS

The Sp-SN-5 questionnaire was successfully translated and cross-culturally adapted into Spanish, and the translated version exhibited adequate properties. The survey was effective in assessing the quality of life of pediatric patients with sinonasal complaints and can be used for this purpose both in a clinical setting and in future research.

Prevalence of allergen sensitization among 1,091 patients with urticaria

The etiology of urticaria is heterogeneous and allergic responses may be involved in it. The aim of the present study was to investigate the prevalence and distribution of sensitivity to inhaled and food allergens among patients with urticaria in Henan province (China). The levels of specific immunoglobulin E (sIgE) were detected using the AllergyScreen test and a total of 524/1,091 cases (48.0%) tested positive for sIgE to at least one of the 19 allergens. The most common inhaled allergens the urticaria patients were sensitive to were D. pteronyssinus (34.5%), cockroach (12.5%) and tree pollen mix (11.1%), while the food allergens with the highest rate of allergic reactions were cashew nut (8.1%), shrimp (6.8%) and crab (6.4%). The positive rates for D. pteronyssinus, dog hair, cockroach, mold mix, tree pollen mix and shrimp in the chronic urticaria group were higher than those in the acute urticaria group (P<0.05). Furthermore, positive rates for the majority of allergens were higher in males than in females and were significantly different between age groups (P<0.05). The results of the present study provided information on the characteristics of allergen sensitization of patients with urticaria and may facilitate the prevention, diagnosis and management of urticaria in Henan province.

Interaction of Alt a 1 with SLC22A17 in the airway mucosa

BACKGROUND

Despite all the efforts made up to now, the reasons that facilitate a protein becoming an allergen have not been elucidated yet. Alt a 1 protein is the major fungal allergen responsible for chronic asthma, but little is known about its immunological activity. Our main purpose was to investigate the ligand-dependent interactions of Alt a 1 in the human airway epithelium.

METHODS

Alt a 1 with and without its ligand (holo- and apo- forms) was incubated with the pulmonary epithelial monolayer model, Calu-3 cells. Allergen transport and cytokine production were measured. Pull-down and immunofluorescence assays were employed to identify the receptor of Alt a 1 using the epithelial cell model and mouse tissues. Receptor-allergen-ligand interactions were analyzed by computational modeling.

RESULTS

The holo-form could activate human monocytes, PBMCs, and polarized airway epithelial (Calu-3) cell lines. The allergen was also transported through the monolayer, without any alteration of the epithelial integrity (TEER). Alt a 1 also induced the production of proinflammatory IL8 and specific epithelial cytokines (IL33 and IL25) by Calu-3 cells. The interaction between epithelial cells and holo-Alt a 1 was found to be mediated by the SLC22A17 receptor, and its recognition of Alt a 1 was explained in structural terms.

CONCLUSIONS

Our findings identified the Alt a 1 ligand as a central player in the interaction of the allergen with airway mucosa, shedding light into its potential role in the immunological response, while unveiling its potential as a new target for therapy intervention.