Hazelnut Allergy.

Background and Objectives: Hazelnuts are frequently involved in IgE-mediated reactions and represent the main culprit of nut allergy in Europe. The clinical presentation varies from mild symptoms limited to the oropharynx [oral allergy syndrome (OAS)], due to the cross-reaction with homologues in pollen allergens and more severe events caused by the primary sensitization to highly stable molecules contained in hazelnuts. The aim of this review is to summarize the most relevant concepts in the field of hazelnut allergy and to provide a practical approach useful in the clinical practice Materials and Methods: References were identified by PubMed searches dating from January 2000 up to November 2020 using the search terms: "component resolved diagnosis" and "Hazelnut allergy. Results: The storage proteins Cor a 9 and Cor a 14 resulted highly specific for primary hazelnut allergy and strongly associated with severe reactions, while the cross reactive Cor a 1, an homolog of the birch Bet v1, were related to OAS. Any cut-off has shown a specificity and sensitivity pattern as high as to replace the oral food challenge (OFC), which still remains the gold standard in the diagnosis of hazelnut allergy. To date there is still no definitive treatment. Hazelnut free-diet and treatment of symptoms with emergency management, including the prescription of auto-injective epinephrine, still represent the main approach. Oral allergen immunotherapy (AIT) appears a promising therapeutic strategy and the definition of individual clinical threshold would be useful for sensitized individuals, caregivers, and physicians to reduce social limitation, anxiety, and better manage food allergy. Conclusions: An accurate diagnostic work-up including clinical history, in vivo and in vitro test including component resolved diagnosis and OFC are essential to confirm the diagnosis, to assess the risk of a severe reaction, and to prescribe an adequate diet and treatment.

Component-Resolved Diagnosis in Food Allergies.

Component-resolved diagnostics (CRD) in food allergies is an approach utilized to characterize the molecular components of each allergen involved in a specific IgE (sIgE)-mediated response. In the clinical practice, CRD can improve diagnostic accuracy and assist the physician in many aspects of the allergy work-up. CRD allows for discriminatory co-sensitization versus cross-sensitization phenomena and can be useful to stratify the clinical risk associated with a specific sensitization pattern, in addition to the oral food challenge (OFC). Despite this, there are still some unmet needs, such as the risk of over-prescribing unnecessary elimination diets and adrenaline auto-injectors. Moreover, up until now, none of the identified sIgE cutoff have shown a specificity and sensitivity profile as accurate as the OFC, which is the gold standard in diagnosing food allergies. In light of this, the aim of this review is to summarize the most relevant concepts in the field of CRD in food allergy and to provide a practical approach useful in clinical practice.

Immune and inflammatory response in bronchiolitis due to respiratory Syncytial Virus and Rhinovirus infections in infants.

Bronchiolitis is a common disease in infancy, mostly due to Respiratory Syncytial Virus and Rhinovirus. In addition to acute infection, viral bronchiolitis is responsible for sequelae including recurrent wheezing and asthma. The analysis of the viral characteristics and of the pathogenesis of the infection shows differences between the two viruses that may be helpful for the development of therapies and preventive strategies.

Safety profile of H1-antihistamines in pediatrics: an analysis based on data from VigiBase.

PURPOSE: H1-antihistamines are commonly used in infants and children for the relief of histamine-mediated symptoms in a variety of conditions. Little is known about their safety profile in these patients. We performed a comparative analysis of the safety profiles of H1-antihistamines using data from the WHO database (VigiBase). METHODS: We selected adverse drug reaction (ADR) reports on H1-antihistamines in children (0-16 years) up to June 2014 from VigiBase. ADRs were codified according to MedDRA terminology. The reporting odds ratios (RORs) with 95% confidence for drug-reaction pairs were calculated. RESULTS: The analysis was performed on 8918 reports related to antihistamines, corresponding to 19503 drug reaction pairs for 68 different drugs. Most of reports involved children aged 2 to 6 years (32%) and 6 to 12 years (34%). Most reported drugs were cetirizine (1608 reports, corresponding to 18%), loratadine (16%), and diphenhydramine (10%). ADRs were classified as serious in 23% of cases, and 400 cases had a fatal outcome. We found a significant associations for several drug-reaction pairs such as levocetirizine and epilepsy (ROR, 6.57; 95% confidence interval [CI], 1.51-28.53) and chlorphenamine and toxic epidermal necrolysis (ROR, 7.29; 95% CI, 2.39-22.2). CONCLUSIONS: H1-antihistamines are among the most used drugs in pediatrics, also in an off-label manner. Our data highlights associations with serious and unexpected ADRs. Educative intervention to clinicians and parents are needed to help doctors to make proper choices on the drug treatment and for the early detection of ADRs to maximize the benefits and reduce the risk of ADRs in these patients.

Prevalence and Clinical Relevance of IgE Sensitization to Profilin in Childhood: A Multicenter Study.

BACKGROUND: Little is known about the prevalence and clinical relevance of hypersensitivity to the plant panallergen profilin in children. OBJECTIVES: The present study aimed to investigate prevalence, risk factors and clinical relevance of profilin sensitization in a large cohort of Italian children of different ages living in different geographic areas. METHODS: Children with pollen allergy enrolled by 16 pediatric outpatient clinics sited in three main geographic areas of Italy were studied. SPT were carried out with commercial pollen extracts and a commercial purified date palm pollen profilin. IgE specific for allergenic pollen molecules, Phl p 12 (grass profilin) and Pru p 3 (peach lipid transfer protein) were tested by ImmunoCAP FEIA. RESULTS: IgE to Phl p 12 (≥0.35 kU/l) was observed in 296 of the 1,271 participants (23%), including 17 of the 108 (16%) preschool children. Profilin SPT was positive (≥3 mm) in 320/1,271 (25%) participants. The two diagnostic methods were concordant in 1,151 (91%, p < 0.0001) cases. Phl p 12 IgE prevalence declined from northern to southern Italy and was directly associated with IgE to Phl p 1 and/or Phl p 5 and Ole e 1. Among children with IgE to Phl p 12, OAS was provoked by kiwi, melon, watermelon, banana, apricot and cucumber. CONCLUSIONS: Profilin sensitization is very frequent among pollen-allergic children, occurs at a very young age and contributes to the development of childhood OAS with a typical pattern of offending foods. Pediatricians should always consider IgE sensitization to profilin while examining pollen-allergic children, even if they are at preschool age.

Patterns of aeroallergen sensitization predicting risk for asthma in preschool children with atopic dermatitis.

OBJECTIVE: Atopic dermatitis (AD) is a chronic inflammatory skin disorder mostly affecting young children. Although several studies aimed to identify the risk factors for asthma in AD children, many aspects still need to be clarified. The aim of this study was to investigate the possible risk factors for asthma at school age in 99 children with early-onset and IgE-mediated AD. METHODS: All children performed clinical evaluation and total and specific IgE assay for a panel of inhalant and food allergens at two different times (t1 and t2) during preschool, and asthma diagnosis was assessed at one follow-up visit (t3) at school age. RESULTS: At t3, 39% of children had developed asthma. Of the variables compared, the sensitization to more than one class of inhalant allergens at t2 (mean age = 30 months) was associated with asthma, with grass (OR = 3.24, p = 0.020) and cat sensitization (OR = 2.74, p = 0.043) as independent risk factors. CONCLUSIONS: The sensitization pattern of a child with early-onset AD, also within the first 2-3 years of life, can reflect his risk to develop asthma. Therefore, testing these children for the more common allergens during this time frame should be recommended to predict the evolution of atopic diseases.

Something Is Changing in Viral Infant Bronchiolitis Approach.

Acute Viral Bronchiolitis is one of the leading causes of hospitalization in the first 12-24 months of life. International guidelines on the management of bronchiolitis broadly agree in recommending a minimal therapeutic approach, not recommending the use of bronchodilators. Guidelines, generally, consider bronchiolitis as a "unique disease" and this runs the risk of not administering therapy in some patients who could benefit from the use of bronchodilators, for instance, in those who will develop asthma later in their life and face first episode in the age of bronchiolitis. Today, there is growing evidence that bronchiolitis is not a single illness but can have different "endotypes" and "phenotypes," based on age, personal or family history of atopy, etiology, and pathophysiological mechanism. There is evidence that some phenotypes of bronchiolitis are more strongly associated with asthma features and are linked to higher risk for asthma development. In these populations, possible use of bronchodilators might have a better impact. Age seems to be the main feature to suggest a good response to a bronchodilator-trial, because, among children > 6 months old with bronchiolitis, the presence of a subset of patients with virus-induced wheezing or the first episode of asthma is more likely. While waiting for new research to define the relationship between therapeutic options and different phenotypes, a bronchodilator-trial (using short-acting ß2 agonists with metered-dose inhalers and valved holding chambers) seems appropriate in every child with bronchiolitis and age > 6 months.

Triage Grading and Correct Diagnosis Are Critical for the Emergency Treatment of Anaphylaxis.

Introduction: Anaphylaxis is one of the most frequent and misdiagnosed emergencies in the pediatric emergency department (PED). We aimed to assess which factors play a major role for a correct diagnosis and an appropriate therapy. Methods: We reviewed the records of children discharged with a diagnosis of anaphylaxis or an allergic reaction over 11 years from 3 hospitals in the Bologna city area. Results: One hundred and sixteen cases matched the criteria (0.03% of the total admittances) and were divided according to the patients' symptoms at arrival: active acute patients [AP], n = 50, or non-acute patients ([NAP], n = 66). At the patients' discharge, anaphylaxis was diagnosed in 39 patients (33.6%). Some features seemed to favor a correct diagnosis: active symptoms at arrival (AP vs. NAP, p < 0.01), high-priority triage code (p < 0.01), and upper airway involvement (p < 0.01). Only 14 patients (12.1%), all in the AP group, received epinephrine, that was more likely administered to patients recognized to have anaphylaxis (p < 0.01) and with cardiovascular, respiratory, or persistent gastrointestinal symptoms (p < 0.02), as confirmed by logistic regression analysis. Conclusions: Anaphylaxis is still under-recognized and under-treated. Correct triage coding and a proper diagnosis seem to foster an appropriate treatment. Physicians often prefer third-line interventions. Specific training for nurses and physicians might improve the management of this disease.

Hypersensitivity to polyethylene glycol in adults and children: An emerging challenge.

Hypersensitivity reactions to polyethylene glycol (PEG) is an emerging challenge and the interest about this disease is growing since PEG is considered one of the possible causes of coronavirus disease 2019 (COVID 19) vaccine-associated anaphylaxis. PEG is used in a wide variety of pharmaceutical, medical, industrial, cosmetic, and food products and can be an active ingredient or used as an excipient. PEG is present in several medications, and it may or may not be present in different formulations and dosages of the same drug. Lack of standardization nomenclature, inadequate labelling of products and lack of knowledge about PEG involvement in hypersensitivity reactions expose patients at risk of presenting multiple reactions before a diagnosis could be made. In this review we describe the main cases published in literature and propose an allergy work-up and management.

A practical management of children with antibiotic allergy.

About 10% of the parents reported that their children are allergic to one drug and the betalactam antibiotics are the most frequently suspected. Even if most of the adverse events following antibiotic prescriptions to children are considered allergic, after a full allergy work-up only a few of the suspected reactions are confirmed. For this reason, many children are incorrectly labelled as "allergic" and this represents an important challenge for the choice of the antibiotic therapy in these "labelled" children, who are frequently improperly deprived of narrow-spectrum antibiotics because considered as allergic. When an allergic reaction is suspected a precise diagnosis and a choice of a safe and effective alternative is essential for the future antibiotic option. In the light of this, the main aim of this paper is to try to provide a practical approach to managing the individuals who have reported adverse reactions to antibiotics.

Update on Interventions in Prevention and Treatment of Pediatric Asthma.

BACKGROUND: Asthma represents a worldwide health problem with a strong morbidity and a major impact on the health care system. Multiple efforts have been made towards the development of new strategies for the prevention and treatment of this disorder. In the light of this the present review of the literature aimed at summarizing the latest advances in prevention and treatment of pediatric asthma with a focus on the most effective options of interventions during the first stages of life. METHODS: References were identified by searches of PubMed. Search terms used in the search were "pediatric asthma", "treatment" and "prevention". We included only meta-analysis, randomized controlled trials, reviews and systematic review articles pertaining to humans and subjects aged 0-18 years. All the interventions have been classified as "non-pharmacological" and "pharmacological". RESULTS: Non-pharmacological interventions have been focused in identifying the genetic and environmental factors underlying the pathogenesis of this disease, including the individual genetic susceptibility, the early allergic sensitization, the role of the environmental microbiome and the exposure to infections and to pollutants. Moreover, the optimization of the existing pharmacological strategies and the development of new treatment options have improved markedly the management of this disease, thereby reducing the health care costs and ameliorating the quality of life of patients. CONCLUSION: Childhood asthma prevention and treatment still represents a worldwide challenge. Future efforts should be aimed at identifying high risk target populations, minimizing the costs of each policy of intervention and increasing adherence to treatment strategies.

An oesophageal spring.

Oesophageal foreign bodies (OFBs) are a relatively common emergency in young children. OFBs are complicated by significant morbidity and mortality because their ingestion often occurs without witnesses, leading to a delay in diagnosis and treatment. We report an occult OFB in an 11-month-old infant who initially presented without any specific respiratory symptoms, mimicking a respiratory infection. Worsening of the patient's cough, which did not show any improvement, despite treatment, and progressive onset of gastrointestinal manifestations (dysphagia, vomiting, and drooling) led to the diagnosis of an OFB (metallic spring). The complex and long-term clinical course of the patient highlights the need of promptly recognizing the presence of an occult OFB. This is because rapid diagnosis and treatment are essential for preventing severe and sometimes irreversible complications.

Allergen Avoidance in Allergic Asthma.

Allergic asthma is the most frequent disease among the chronic respiratory disorders in pediatric age with an important social impact. In the last years, many efforts have been made to identify effective preventive approaches to get a better control of symptoms and to obtain the best future outcomes for the patients. In patients with allergic asthma triggered by the exposure to indoor allergens, the avoidance is the first intervention to prevent the appearance or the worsening of bronchial symptoms. This review article summarized the most recent evidence from literature about the efficacy of specific control interventions for the most important allergens. Even if a wide spectrum of interventions has been suggested and may help to reduce exposure to trigger allergy for sensitized patients suffering from respiratory allergy, evidence supporting the efficacy of these approaches is still weak and subject of controversy. However, the exposure control to specific airborne allergens is still widely recommended and may be effective as part of a holistic approach to reduce the severity of allergic respiratory symptoms in sensitized individuals.

Acute Asthma in the Pediatric Emergency Department: Infections Are the Main Triggers of Exacerbations.

BACKGROUND: Asthma exacerbations are a common reason for Emergency Department (ED) visits in children. AIM: To analyze differences among age groups in terms of triggering factors and seasonality and to identify those with higher risk of severe exacerbations. METHODS: We retrospectively revised the files of children admitted for acute asthma in 2016 in our Pediatric ED. RESULTS: Visits for acute asthma were 603/23197 (2.6%). 76% of the patients were <6 years old and 24% ≥6. Infections were the main trigger of exacerbations in both groups; 33% of the school-aged children had a triggering allergic condition (versus 3% in <6 years; p < .01). 191 patients had a previous history of asthma; among them, 95 were ≥6 years, 67% of whom were not using any controller medication, showing a higher risk of a moderate-to-severe exacerbation than those under long-term therapy (p < .01). Exacerbations peaked in autumn and winter in preschoolers and in spring and early autumn in the school-aged children. CONCLUSIONS: Infections are the main trigger of acute asthma in children of any age, followed by allergy in the school-aged children. Efforts for an improved management of patients affected by chronic asthma might go through individualized action plans and possibly vaccinations and allergen-avoidance measures.

Clinical practice recommendations for allergen-specific immunotherapy in children: the Italian consensus report.

Allergen-specific immunotherapy (AIT) is currently recognized as a clinically effective treatment for allergic diseases, with a unique disease-modifying effect. AIT was introduced in clinical practice one century ago, and performed in the early years with allergenic extracts of poor quality and definition. After the mechanism of allergic reaction were recognized, the practice of AIT was refined, leading to remarkable improvement in the efficacy and safety profile of the treatment. Currently AIT is accepted and routinely prescribed worldwide for respiratory allergies and hymenoptera venom allergy. Both the subcutaneous (SCIT) and sublingual (SLIT) routes of administration are used in the pediatric population.AIT is recommended in allergic rhinitis/conjunctivitis with/without allergic asthma, with an evidence of specific IgE-sensitization towards clinically relevant inhalant allergens. Long-term studies provided evidence that AIT can also prevent the onset of asthma and of new sensitizations. The favorable response to AIT is strictly linked to adherence to treatment, that lasts 3-5 years. Therefore, several factors should be carefully evaluated before starting this intervention, including the severity of symptoms, pharmacotherapy requirements and children and caregivers' preference and compliance.In recent years, there have been increasing interest in the role of AIT for the treatment of IgE-associated food allergy and extrinsic atopic dermatitis. A growing body of evidence shows that oral immunotherapy represents a promising treatment option for IgE-associated food allergy. On the contrary, there are still controversies on the effectiveness of AIT for patients with atopic dermatitis.This consensus document was promoted by the Italian Society of Pediatric Allergy and Immunology (SIAIP) to provide evidence-based recommendations on AIT in order to implement and optimize current prescription practices of this treatment for allergic children.

Topical corticosteroid phobia in parents of pediatric patients with atopic dermatitis: a multicentre survey.

BACKGROUND: Families of children affected with atopic dermatitis (AD) often report fear and anxiety regarding treatment with topical corticosteroids (TCS), which may lead to reduced compliance. The objective of our study was to measure, through a standardized questionnaire, fear of TCS in families of pediatric patients with AD and to identify items associated with fear. METHODS: Families of pediatric patients with AD were enrolled in 9 Italian centers of pediatric dermatology. Enrolled parents were invited to fill in a questionnaire including questions on sociodemographic and clinical characteristics and 3 sets of questions on corticosteroid phobia (general fear, specific fears, behaviours regarding TCS). Determinants of the level of general fear were investigated through multivariable analysis. RESULTS: A total of 300 outpatients with AD were enrolled. Most parents (80%) had a high instruction level. Eighty-one percent reported to have a certain amount of fear of TCS. At the multivariable analysis, fear of TCS was associated with the following items: believing that TCS treatment advantages do not overweight disadvantages (P = 0.011); believing that TCS may be dangerous independently from the specific side effect (P < 0.001). Moreover, TCS fear was associated with fear of applying too much cream (P = 0.001). CONCLUSION: TCS phobia is widespread among Italian families of children with AD. Fear of TCS is associated with fear of applying too much cream, thus increasing the risk of poor compliance and treatment failure. Therapeutic education of families on the use of TCS should be implemented.

Consensus Conference on Clinical Management of pediatric Atopic Dermatitis.

The Italian Consensus Conference on clinical management of atopic dermatitis in children reflects the best and most recent scientific evidence, with the aim to provide specialists with a useful tool for managing this common, but complex clinical condition. Thanks to the contribution of experts in the field and members of the Italian Society of Pediatric Allergology and Immunology (SIAIP) and the Italian Society of Pediatric Dermatology (SIDerP), this Consensus statement integrates the basic principles of the most recent guidelines for the management of atopic dermatitis to facilitate a practical approach to the disease. The therapeutical approach should be adapted to the clinical severity and requires a tailored strategy to ensure good compliance by children and their parents. In this Consensus, levels and models of intervention are also enriched by the Italian experience to facilitate a practical approach to the disease.

Peanut sensitization profiles in Italian children and adolescents with specific IgE to peanuts.

Peanuts are one of the most relevant foods implicated in IgE-mediated adverse reactions in pediatric population. This study aimed to evaluate the pattern of sensitization towards five peanut allergenic components (rAra h 1, 2, 3, 8 and 9) in a population of Italian children and adolescents with specific IgE (sIgE) to peanut. rAra h 9 was the main allergen implicated in peanut sensitization (58%), followed by rAra h 8 (35%), rAra h 2 (27%), rAra h 3 (23%) and rAra h 1 (12.5%). rAra h 1, 2, and 3 were the main allergenic components in young children: 8/13 (62%) between 2 and 5 years, 8/23 (35%) between 6 and 11 years, and 3/12 (25%) between 1 and 16 years. No differences were found among the levels of sIgE towards rAra h 1, 2, 3, and 9 in the three groups; in contrast, the levels of sIgE against rAra h 8 showed an increasing trend according to age. In conclusion rAra h 1, 2, and 3 were the prevalent sensitizing allergens during the first years of life in Italian patients with sIgE to peanuts ("genuine" allergy); in contrast rAra h 9 and 8 were mainly involved in school-age children and adolescents with pollen allergy ("secondary" sensitization).

Citrus allergy from pollen to clinical symptoms.

Allergy to citrus fruits is often associated with pollinosis and sensitization to other plants due to a phenomenon of cross-reactivity. The aims of the present study were to highlight the cross-reactivity among citrus and the major allergenic pollens/fruits, throughout clinical and molecular investigations, and to evaluate the sensitization frequency to citrus fruits in a population of children and adults with pollinosis. We found a relevant percentage of sensitisation (39%) to citrus fruits in the patients recruited and in all of them the IgE-mediated mechanism has been confirmed by the positive response to the prick-to-prick test. RT-PCR experiments showed the expression of Cit s 1, Cit s 3 and a profilin isoform, already described in apple, also in Citrus clementine pollen. Data of multiple sequence alignments demonstrated that Citrus allergens shared high percentage identity values with other clinically relevant species (i.e. Triticum aestivum, Malus domestica), confirming the possible cross-allergenicity citrus/grasses and citrus/apple. Finally, a novelty of the present work has been the expression of two phospholipaseA2 isoforms (PLA2 α and ß) in Citrus as well as in Triticum pollens; being PLA2 able to generate pro-inflammatory factors, this enzyme could participate in the activation of the allergenic inflammatory cascade.