Molecular Diagnosis in House Dust Mite-Allergic Patients Suggests That Der p 23 Is Clinically Relevant in Asthmatic Children.

BACKGROUND: Patterns of sensitization to house dust mites depend on geographic area and are important in clinical practice. However, the role of molecular diagnosis is not currently defined. We sought to characterize a pediatric population by focusing on sensitization to different mite species and major mite components in order to assess the clinical relevance of sensitization to allergenic components in our practice. METHODS: Consecutive children with respiratory allergy sensitized to house dust mites (determined by skin prick test [SPT]) were recruited. We determined specific IgE to nDer p 1, rDer p 2, and rDer p 23 using ImmunoCAP and sIgE using ImmunoCAP-ISAC microarray. Patients were followed up for 3 years. RESULTS: A total of 276 children were recruited. The frequency of sensitization was 86.6% for nDer p 1, 79.3% for rDer p 2, and 75.8% for rDer p 23. Lepidoglyphus species was the most common storage mite detected by SPT. Twenty-six patients (9.4%) were not sensitized to Der p 1 or Der p 2. It is noteworthy that IgE binding to Der p 23 was positive in 14 (53.8%). Asthmatic patients, especially those with a persistent moderate-severe phenotype, more frequently recognized the 3 major allergens. CONCLUSIONS: Most patients with mite allergy were sensitized to the major allergens Der p 1, Der p 2, and Der p 23. Of the allergens evaluated, 5% were sensitized to Der p 23 but not to Der p 1 or Der p 2. Sensitization to Der p 23 should be considered in the diagnosis and treatment of mite allergy, especially in patients with moderate-severe asthma, because it may worsen the clinical phenotype.

Molecular diagnosis in house dust mite-allergic patients suggests that Der p 23 is clinically relevant in asthmatic children

BACKGROUND: Patterns of sensitization to house dust mites depend on geographic area and are important in clinical practice. However, the role of molecular diagnosis is not currently defined. We sought to characterize a pediatric population by focusing on sensitization to different mite species and major mite components in order to assess the clinical relevance of sensitization to allergenic components in our practice. METHODS: Consecutive children with respiratory allergy sensitized to house dust mites (determined by skin prick test [SPT]) were recruited. We determined specific IgE to nDer p 1, rDer p 2, and rDer p 23 using ImmunoCAP and sIgE using ImmunoCAP-ISAC microarray. Patients were followed up for 3 years. RESULTS: A total of 276 children were recruited. The frequency of sensitization was 86.6% for nDer p 1, 79.3% for rDer p 2, and 75.8% for rDer p 23. Lepidoglyphus species was the most common storage mite detected by SPT. Twenty-six patients (9.4%) were not sensitized to Der p 1 or Der p 2. It is noteworthy that IgE binding to Der p 23 was positive in 14 (53.8%). Asthmatic patients, especially those with a persistent moderate-severe phenotype, more frequently recognized the 3 major allergens. CONCLUSIONS: Most patients with mite allergy were sensitized to the major allergens Der p 1, Der p 2, and Der p 23. Of the allergens evaluated, 5% were sensitized to Der p 23 but not to Der p 1 or Der p 2. Sensitization to Der p 23 should be considered in the diagnosis and treatment of mite allergy, especially in patients with moderate-severe asthma, because it may worsen the clinical phenotype

ANTECEDENTES: El perfil de sensibilización a los ácaros del polvo depende del área geográfica y es importante en la práctica clínica. Sin embargo, el papel del diagnóstico molecular no ha sido del todo definido. Nuestro objetivo fue la caracterización del perfil de sensibilización de una población pediátrica a diferentes especies de ácaros; y evaluar la sensibilización a componentes alergénicos y su relevancia en nuestra práctica clínica. MÉTODOS: Se reclutaron de forma consecutiva pacientes con alergia respiratoria y sensibilización a ácaros del polvo doméstico mediante pruebas cutáneas. Se determinó la IgE específica por ImmunoCAP a nDer p 1, rDer p 2, rDer p 23 y la sIgE mediante el microarray de ImmunoCAP ISAC. Los pacientes fueron evaluados durante tres años según práctica cínica habitual. RESULTADOS: Se reclutaron un total de 276 niños. La sensibilización fue de 86,6% a nDer p 1, 79,3% a rDer p 2 y 75,8% a rDer p 23. Lepidoglyphus fue el ácaro de almacén más común según prueba cutánea. Un total de veintiséis pacientes (9,4%) no estaban sensibilizados a Der p 1 ni Der p 2; cabe destacar que 14 de ellos (53,8%) presentaban IgE positiva a Der p 23. Los pacientes con asma, y en especial los de fenotipo persistente moderado y grave, reconocieron con mayor frecuencia los tres alérgenos mayores. CONCLUSIONES: La mayoría de nuestra población pediátrica con alergia a ácaros está sensibilizada a los alérgenos mayores Der p 1, Der p 2 y Der p 23. Un 5% estaba sensibilizado a Der p 23, pero no a Der p 1 ni a Der p 2. La sensibilización a Der p 23 debe considerarse en el diagnóstico y tratamiento de la alergia a ácaros, especialmente en pacientes con asma persistente moderada y grave

'Real-life' experience in asthmatic children treated with omalizumab up to six-years follow-up.

INTRODUCTION AND OBJECTIVES: Omalizumab is present in international guidelines for the control of severe asthma, but data on the long-term effects in children are limited. Our objective was to perform a 'real-life' long-term trial of omalizumab in children with allergic asthma. MATERIALS AND METHODS: An observational single center 'real-life' study was performed. Data for treatment, lung function, side effect, asthma exacerbations and hospitalizations were recorded at six months and annually. RESULTS: Forty-eight patients <18 years of age were enrolled. Median treatment period was 2.9 (0.5-6). Fluticasone dose for the maintenance treatment decreases significantly at six months (452mcg/day to 329.89mcg/day, respectively). This difference was maintained throughout the follow-up. Nobody used oral corticosteroid after six months. The rate of hospital admissions and visits to the emergency department for asthma exacerbations decreased significantly in the third years and fourth years follow-up, respectively. There was an improvement in lung function. Mean values of FEV1 and FEF25-75% before treatment were 79.88 and 62.94, respectively; after six months of treatment a statistically significant change was seen with a mean FEV1 of 92.29 and FEF25-75% of 76.31 (p=0.0001). Lung function values were above normal throughout the six years of treatment. No side effects were reported. CONCLUSIONS: Overall in 'real life' omalizumab in children reduces asthma exacerbations and hospitalizations, improves lung function, and decreases the maintenance therapy. It is shown to be safe for up to six years of treatment in children.

Asymptomatic LTP sensitisation is common in plant-food allergic children from the Northeast of Spain.

BACKGROUND: The sensitisation profile at molecular level in plant-food allergy is complex. Several allergens may be involved, with different potential for severe reactions. lipid transfer proteins (LTP) are considered the most relevant plant-food allergens in adults in Mediterranean countries, but less is known in children. AIM: To describe the clinical pattern and sensitisation profile of children with plant-food allergy and LTP sensitisation from Northeast Spain. METHODS: Children with history of immediate reaction to plant-food(s), positive skin-prick-test to the culprit plant-food(s) and specific-IgE to plant-food LTPs were analysed. RESULTS: 130 children were included. 69.2% (90/130) had reacted to ≥2 taxonomically unrelated plant-foods. Peach, walnut, hazelnut and peanut were most frequently involved. Reactions severity ranged from anaphylaxis (45.4%, 59/130) to oral symptoms only. Sensitisation to a particular plant-food LTP not always caused clinical symptoms with that plant-food; 69% (40/58) and 63% (17/27) of peach- and walnut-tolerant subjects had positive rPru p 3 and nJug r 3 specific IgE, respectively. 65.4% (85/130) of children were also sensitised to storage proteins, which was associated to anaphylaxis and nut allergy. However, 60% of patients without nuts/seeds allergy were sensitised to storage proteins. Specific-IgE levels to LTPs and/or storage proteins were not useful to predict allergy (vs. tolerance) to peach, walnut, peanut or hazelnut. CONCLUSIONS: Sensitisation to LTP and/or storage proteins without clear clinical significance is relatively common. Prospective longitudinal studies are required to evaluate the relevance of these silent sensitisations over time. Caution is required when interpreting the results of molecular-based diagnostic tools in clinical practice.