Allergy testing in childhood: using allergen-specific IgE tests

Characterizing Non-T2 Asthma: Key Pathways and Molecular Implications Indicative of Attenuated Th2 Response

Non-Type 2 (non-T2) asthma is characterized by a lack of allergic sensitization and normal to low total IgE levels. We aimed to explore molecular mechanisms and pathways differentiating non-T2 from T2-high pediatric asthma. We analyzed peripheral blood RNA samples from 11 non-T2 and 17 T2-high pediatric asthma patients using bulk RNA sequencing. Differentially expressed genes (DEGs) were identified, followed by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, and Protein-Protein Interaction (PPI) network construction. Gene Set Enrichment Analysis (GSEA) and Ingenuity Pathway Analysis (IPA) were employed to explore significance of these DEGs. We utilized independent public datasets GSE145505 to validate our findings. We investigated Th cytokine profiles in an independent cohort of pediatric patients with non-T2 asthma (n = 38) and T2-high asthma (n = 64). We demonstrated that the total serum IgE levels of children with non-T2 asthma (128.4 ± 159.5 IU/mL) was significantly lower than that of those with T2-high asthma (405.8 ± 252.1 IU/mL). Our analysis revealed 136 DEGs distinguishing non-T2 from T2-high asthma. IPA identified predicted inhibition of IgE-FcεRI signaling pathways in non-T2 asthma. Our DEG data showed the expression of IGHV4-39, IGLV1-40, IGLV1-47, IGLV1-44, IGHV1-69, IGLV6-57, IGLV3-19, IGLV3-1, and IGLC7 were downregulated in our non-T2 asthma patient. The non-T2 group exhibited significantly higher concentrations of IL-2, IFN-γ, IL-6, and IL-17A compared to the T2-high group. Our integrated analysis differentiated non-T2 from T2-high asthma by revealing downregulation of specific immunoglobulin genes influencing FcεRI signaling, elevated Th1 cytokines and Th17 cytokines might affect IgE associated sensitization and alter Th2 allergic response.

Climate change from the Asia-Pacific perspective: What an allergist needs to know and do

Allergic diseases such as asthma, atopic dermatitis, and food allergies are a burgeoning health challenge in the Asia-Pacific region. Compounding this, the region has become increasingly susceptible to the impacts of climate change. The region has weathered extreme precipitation, intense heat waves, and dust storms over the recent decades. While the effects of environmental and genetic factors on allergic diseases are well understood, prevailing gaps in understanding the complex interactions between climate change and these factors remain. We aim to provide insights into the various pathways by which climate change influences allergic diseases in the Asia-Pacific population. We outline practical steps that allergists can take to reduce the carbon footprint of their practice on both a systemic and patient-specific level. We recommend that allergists optimize disease control to reduce the resources required for each patient's care, which contributes to reducing greenhouse gas emissions. We encourage the responsible prescription of metered dose inhalers by promoting the switch to dry powder inhalers for certain patients, at each clinician's discretion. We also recommend the utilization of virtual consultations to reduce patient travel while ensuring that evidence-based guidelines for rational allergy management are closely adhered to. Finally, eliminating unnecessary testing and medications will also reduce greenhouse gas emissions in many areas of medical care.

[History and physycal examination]

The most effective method for diagnosing food allergy is the clinical history, which includes anamnesis and physical examination. The anamnesis must include a directed and detailed questioning, and together with the physical examination, it will provide the necessary data to guide the diagnosis and suggest whether the pathophysiology is mediated or not by IgE, which is relevant for the selection and interpretation of the tests. specific and establish the accurate diagnosis, in addition to evaluating the possibility of distinguishing between the different differential diagnoses. It is important to assess the clinical history, because no in vivo or in vitro test is relevant if it is not confirmed with it. Even if there is a strong history of food allergy detected in the history, positive tests can confirm the diagnosis without the need for oral challenge, thus avoiding the risk and cost of performing it. The expression of food allergy is influenced by non-modifiable risk factors that include sex, race and genetics (familial), and modifiable factors: atopic dermatitis, vitamin D deficiency, diet high in polyunsaturated fats and deficient in antioxidants, consumption of antacid drugs, obesity, increased hygiene, influence of the microbiota, time and route of food exposure (increased risk by delaying oral ingestion of allergens and concomitant environmental exposure of the same that leads to sensitization and allergy).

[Physiopathology of food allergies]

Food allergy is an adverse reaction to certain foods that have demonstrated "immunological mechanisms"; therefore, this term covers both food allergies mediated or not by immunoglobulin E (IgE). The common pathophysiological mechanism among forms of allergy to foods mediated or not by IgE is found in the failure of clinical and immunological tolerance towards that food. The induction and maintenance of immunological tolerance depends on the active generation of regulatory T cells specific for food antigens. This process is influenced by genetic factors (FOXP3 genes) and epigenetic factors conditioned by the environment (diet, microbiota, and their products). Since the intestinal microbiome can normally promote oral tolerance, current evidence suggests that perturbations of the microbiome may correlate, or even predispose, with food allergy. Understanding the pathogenic mechanism underlying IgE-mediated food allergies allows the implementation of measures aimed at restoring clinical and immunological tolerance. Knowledge of the mechanisms of food allergy will improve the outlook for patients with more severe immediate food allergies and anaphylaxis, as well as those who have comorbidities (atopic dermatitis, eosinophilic esophagitis and EGEIDs).

The Heterogeneity of Ovomucoid-Specific IgE Idiotype Is Associated With Egg Allergy Symptom Severity

Immunoglobulin E (IgE)-mediated egg allergy presents as one of the most common food allergies. The level of specific IgE (sIgE) antibody is widely used as an important in vitro diagnostic indicator. However, sIgE antibody levels are often inconsistent with the clinical manifestations of patients. The heterogeneity of egg-specific IgE idiotypes (sIgE-IDs) may help reflect clinical egg allergy severity. Eight peptides were synthesized, corresponding to the linear epitopes of ovomucoid (OVM). The sIgE-IDs of egg-allergic patients were detected by enzyme-linked immunosorbent assay. Fresh peripheral blood was collected from patients with different heterogeneity strength of sIgE-ID, and egg extract was used as a stimulus to the basophil activation test (BAT). RBL-2H3 cells were sensitized with serum with different strength of sIgE-ID heterogeneity and the release rate of β-hexosaminidase was calculated. Among 75 patients with egg allergy, 24% had sIgE for all epitopes and 85% had sIgE for at least one epitope. Analysis of individual patients revealed differences in epitope recognition patterns among the patients, that is, heterogeneity in sIgE-ID. More importantly, the number of IgE-positive peptides had a strong correlation with allergic symptoms in egg-allergic patients (r = 0.706). BAT and RBL-2H3 cell degranulation confirmed that higher sIgE-ID heterogeneity strength was more effective in inducing effector cell responses. Our results suggest that the greater the heterogeneity strength of OVM-sIgE-ID, the more severe the allergic symptoms.

Maternal energy-adjusted fatty acid intake during pregnancy and the development of cows' milk allergy in the offspring

Cows' milk allergy (CMA) is one of the earliest manifestations of allergic diseases. Early dietary factors, like maternal diet during pregnancy, may play a role in the development of allergic diseases in the offspring. We aimed to investigate the association between maternal intake of fatty acids during pregnancy and the risk of CMA in the offspring. Our study was conducted in a population-based cohort, the Finnish Type 1 Diabetes Prediction and Prevention study. We collected the maternal dietary data by a validated FFQ. We obtained the information on CMA in the study participants (n 448) from registers and from the parents. Dietary data and information on CMA were available for 4921 children. We used logistic regression in the analyses, and fatty acid intakes were energy adjusted. The maternal intake of SFA, MUFA, PUFA, n-3 PUFA, n-6 PUFA, trans fatty acids, ratio of n-3 PUFA to n-6 PUFA or ratio of linoleic acid to α-linolenic acid was not associated with the risk of CMA in the offspring when adjusted for perinatal factors, background factors, parental history of asthma or allergic rhinitis and infant animal contacts. The intake of α-linolenic acid was associated with a decreased risk (OR 0·72; 95 % CI 0·56, 0·93) of CMA in the offspring of mothers without a history of allergic rhinitis or asthma. In conclusion, the maternal intake of fatty acids during pregnancy is not associated with the risk of CMA in the offspring.

EAST in Children with Allergic rhinitis: Experience from Indian Tertiary Centre

Allergic rhinitis (AR) is recognized as a growing global health disease with considerable importance among children and adolescents. This study aims to study the clinical and sensitization profile of children with allergic rhinitis using EAST. All children presenting to pediatric ENT outpatient with a clinical diagnosis of AR were prospectively recruited. Detailed demographic and clinical history including self-reported allergens, predominant symptoms and associated comorbid conditions were obtained. Severity of symptoms was graded on a visual analogue scale. Specific Ig E antibodies to 20 inhalant allergens was measured using EAST (EUROIMMUN, Germany).The pattern of sensitization was analyzed with respect to age, symptoms, associated comorbid conditions and urbanization. We recruited 328 children with a clinical diagnosis of AR (Mean age 10.3 year, IQR 8-13 years) Nasal block was the predominant symptom across all age groups, sneezing became more troublesome during adolescence. In 191 children sera were tested for allergen specific IgE, 119 (62.3%) showed positive sensitization. The most common sensitization noted was for cockroach, followed by dust mite and pollens. Majority had polysensitization (73%). Those who were predominantly sneezers were more likely to be sensitized with indoor allergens (p < 0.05). Among the comorbid conditions, asthma and atopic dermatitis accounted for maximum non ENT physician visits. The pattern of sensitization did not vary with age, urbanization or comorbid condition. This study highlights the clinical and sensitization profile of children with AR in South East India. Various peculiarities of this community has been presented which needs further attention.

Associations of early-life pet ownership with asthma and allergic sensitization: a meta-analysis of >77,000 children from the EU Child Cohort Network

BACKGROUND

Studies examining associations of early-life cat and dog ownership with childhood asthma have reported inconsistent results. Several factors could explain these inconsistencies, including type of pet, timing and degree of exposure.

OBJECTIVE

To study associations of early-life cat and dog ownership with school-age asthma, including the role of type (cat versus dog), timing (never, prenatal or early childhood) and degree (number) of ownership, and the role of allergic sensitisation.

METHODS

We used harmonised data from 77,434 mother-child dyads aged 5-11 years from nine birth cohorts in the EU Child Cohort Network. Associations were examined through the DataSHIELD platform using adjusted logistic regression models, fitted separately for each cohort and combined using random-effects meta-analysis.

RESULTS

Early-life cat and dog ownership ranged between 12-45% and 7-47% respectively, and prevalence of asthma between 2-20%. There was no overall association between either cat or dog ownership and asthma (OR: 0.97 (95% CI: 0.87-1.09) and 0.92 (0.85-1.01), respectively). Timing and degree of ownership did not strongly influence associations. Cat and dog ownership were also not associated with cat- and dog-specific allergic sensitisation (OR: 0.92 (0.75-1.13) and 0.93 (0.57-1.54), respectively). However, cat- and dog-specific allergic sensitisation were strongly associated with school-age asthma (OR: 6.69 (4.91-9.10) and 5.98 (3.14-11.36), respectively). There was also some indication of an interaction between ownership and sensitisation, suggesting that ownership may exacerbate the risks associated with pet-specific sensitisation, but offer some protection against asthma in the absence of sensitisation.

CONCLUSION

Our findings do not support early-life cat and dog ownership in themselves increasing the risk of school-age asthma, but suggest that ownership may potentially exacerbate the risks associated with cat- and dog-specific allergic sensitisation.

Associating school doctor interventions with the benefit of the health check: an observational study

BACKGROUND

The benefits of school doctor interventions conducted at routine general health checks remain insufficiently studied. This study explored the associations of school doctor interventions with the doctor-evaluated and parent-evaluated benefits of routine health checks.

METHODS

Between August 2017 and August 2018, we recruited a random sample of 1341 children from grades 1 and 5 from 21 Finnish elementary schools in 4 municipalities. Doctors routinely examined all children, who were accompanied by parents. The doctor-reported interventions were categorised into six groups: instructions and/or significant discussions, prescriptions, laboratory tests and/or medical imaging, scheduling of follow-up appointments, referrals to other professionals and referrals to specialised care. Doctors evaluated the benefit of the appointment using predetermined criteria, and parents provided their subjective perceptions of benefit. Interventions and reported benefit were compared using multilevel logistic regression.

RESULTS

Doctors reported 52% and parents 87% of the appointments with interventions beneficial. All interventions were independently associated with doctor-evaluated benefit (ORs: 1.91-17.26). Receiving any intervention during the appointment was associated with parent-evaluated benefit (OR: 3.25, 95% CI 2.22 to 4.75). In analyses of different interventions, instructions and/or significant discussions (OR: 1.71, 95% CI 1.20 to 2.44), prescriptions (OR: 7.44, 95% CI 2.32 to 23.91) and laboratory tests and/or medical imaging (OR: 3.38, 95% CI 1.34 to 8.55) were associated with parent-evaluated benefit. Scheduled follow-up appointments and referrals to other professionals showed no significant association with parent-evaluated benefit.

CONCLUSIONS

Doctors and parents valued the appointments with interventions. Parents especially appreciated immediate help and testing from the doctor.

TRIAL REGISTRATION NUMBER

NCT03178331.

Incidence of allergen-specific and total immunoglobulin E positivity in children undergoing adenotonsillectomy

AIM

To conduct a prospective, consecutive cohort study to evaluate the incidence of allergen-specific and total immunoglobulin E (IgE) in a paediatric population undergoing adenotonsillectomy for sleep-disordered breathing.

METHODS

A total of 64 consecutive patients presenting for adenotonsillectomy at a single centre were recruited over a period of 3 months. All patients underwent adenotonsillectomy and had allergen-specific and total IgE serum testing at the time of anaesthesia induction. Pre-operative history and examination were conducted to determine clinical allergy. Caregivers completed the Sleep-Related Breathing Disorder scale of the Paediatric Sleep Questionnaire and the Mini Rhinoconjunctivitis Quality of Life Questionnaire at baseline and at 6 weeks post-operatively.

RESULTS

A total of 37 (57.8%) patients had either allergen-specific or total IgE positivity. House dust mite was the most prevalent allergen-specific IgE finding, being present in moderate to high levels in 14 (21.9%) patients. A total of 17 (26.6%) patients had a history of atopy, while 34 (53.1%) had examination findings suggestive of allergy. Neither serum IgE testing nor clinical history and examination were independently associated with residual symptoms post adenotonsillectomy. Patients with concomitant serum IgE positivity and clinical allergy had higher residual symptom scores compared to those who did not using both Sleep-Related Breathing Disorder scale of the Paediatric Sleep Questionnaire (P = 0.035) and Mini Rhinoconjunctivitis Quality of Life Questionnaire (P = 0.02) questionnaires.

CONCLUSIONS

Our prospective, consecutive cohort of patients reflect a greater incidence of serum IgE positivity compared to historical figures. When utilised with clinical findings on history and examination, serum IgE is a useful adjunct that is associated with greater residual symptoms post-adenotonsillectomy.

Allergies, Allergic Comorbidities and the Home Environment in Pediatric Asthma in Southern Florida

Background: Environmental exposure is critical in sensitization to environmental allergens and pediatric asthma morbidity, especially in tropical climates where children are perennially exposed to bioaerosols, such as pollen and mold spores, and endotoxins. Objective: This cross-sectional study examines the association of allergies, associated allergic comorbidities, and the home environment separately and synergistically in pediatric asthma, including in asthma prevalence, severity of asthma, and undiagnosed asthma, in South Florida. Methods: An online survey was administered to the parents of children attending two of the University of Miami pediatric clinics from June to October 2016. Descriptive, factor, and multivariate regression analyses were used to analyze the data. Results: Of 163 children, 22% (36) children had physician-diagnosed asthma; 10% and 32% had allergic rhinitis diagnosis and rhinitis symptoms, respectively, in the past. The allergy diagnosis age was 2.3 years higher than the asthma diagnosis age (p < 0.01). Children with ≥ 2 allergies were 12.8 times more likely to have physician-diagnosed asthma than those without allergies (p < 0.01). Children with allergies and allergic rhinitis were 4.3 (p < 0.05) times more likely to have asthma, and those with asthma were 15 (p < 0.05) times more likely to have an asthma attack than those without known allergies and allergic rhinitis. Conclusion: Allergies and associated comorbidities are risk factors of asthma, asthma persistence, and multiple allergies exacerbate their effects. Early screening for allergies and treatment are warranted to manage asthma. Since the home environment plays an important role in sensitization to allergens, further research is needed to assess home-environment-mediated allergic conditions in the onset and persistence of asthma.

Question 6: What is the use of allergy testing in children with asthma?

Disagreement exists between asthma guidelines on the routine use of allergy testing in the diagnostic work-up of a child with persistent asthma, although the important role of inhalant allergy in the pathophysiology of asthma and allergic rhinitis is undisputed. The usefulness of screening for inhalant allergies in asthma is connected to the efficacy of allergen reduction measures and specific immunotherapy, both of which appear to be more effective in children than in adults. Allergen-specific exposure reduction recommendations are therefore an essential part of childhood asthma management. Such recommendations should be guided by appropriate diagnosis of inhalant allergy, based on a structured allergy history and results of sensitization tests. Specific IgE testing and skin prick testing show comparable results in identifying clinically important sensitizations. Although a therapeutic medication trial can be started pragmatically in children with asthma without diagnosing their inhalant allergy, we recommend making or excluding an accurate diagnosis of inhalant allergy.

Proven Food-Induced Acute Urticaria and Predictive Factors for Definitive Diagnosis in Childhood

BACKGROUND

Urticaria can be the only sign of a food allergy or can be seen together with other signs and symptoms of a food allergy.

OBJECTIVE

To determine the demographic, etiologic, and clinical features of food-induced acute urticaria in childhood.

METHODS

Patients suspected of food-induced acute urticaria were included in this prospective cross-sectional multicenter study.

RESULTS

Two hundred twenty-nine urticaria cases were included in this study. Seventeen patients who did not meet the inclusion criteria of the study were excluded. Of the 212 included cases, 179 (84.4%) were diagnosed with definitive food-induced acute urticaria. The most common foods causing acute urticaria were cow's milk, hen's eggs, and nuts in 56.4, 35.2, and 19% of cases, respectively. The positive predictive value of a history of milk-induced acute urticaria together with a milk-specific IgE >5 kU/L for cow's milk-induced acute urticaria was 92% (95% CI: 81-96%). A history of cow's milk-induced and/or hen's egg-induced acute urticaria was consistent with a definitive diagnosis of food-induced urticaria (Chen's kappa: 0.664 and 0.627 for milk and eggs, respectively). Urticaria activity scores were higher in patients with food-induced acute urticaria (p = 0.002).

CONCLUSION

Cow's milk, hen's eggs, and nuts were the most common allergens in the etiology of childhood food-induced acute urticaria. Although the urticaria activity score provides guidance for diagnosis, an oral food challenge is often essential for the definitive diagnosis of a patient with a history of food-induced acute urticaria.

Allergy-Related Symptoms Are Poorly Predicted by IgE and Skin Prick Testing in Early Life

INTRODUCTION

In childhood, the so-called allergic march involves progression from IgE sensitization to allergy-related symptoms. Both IgE sensitization and relevant clinical symptoms are required for the diagnosis of allergy, but concordance between test results and clinical symptoms varies greatly, creating challenges for the diagnostics and for the prediction of outcomes. We assessed the prevalence of IgE sensitization and allergy symptoms, concordance between 2 IgE sensitization testing methods, and predictive value of these tests in relation to clinical symptoms in young Finnish children.

METHODS

The current study included 2 series of children: a birth cohort, in which the participants were followed prospectively from birth up to 3 years, and a young children cohort observed from 3 to 5 years of age. They were regularly monitored for sensitization by measuring serum allergen-specific IgEs (sIgEs) and performing skin prick tests (SPTs). The emergence of atopic dermatitis, wheezing, and symptoms associated with food allergies was recorded.

RESULTS

Over the first 5 years of life, the prevalence of sIgE sensitization was 46%, while it was 36% for positive SPTs. Disease prevalence was 26% for atopic dermatitis, 25% for wheezing, and 19% for symptoms associated with food allergies. Concordance between sIgE and SPT results was good for aeroallergens, but poor for dietary allergens. The association between clinical symptoms and sensitization was stronger at 5 years than at 3 years of age. The proportion of children with concordant combinations of allergy symptoms and sensitization markers in contrast to those with discordant combinations increased from 3 to 5 years.

CONCLUSION

In early childhood, testing for IgE sensitization predicts allergy-related symptoms in an age-dependent manner, but not particularly well. Tests predict symptoms caused by aeroallergens clearly better than those caused by dietary allergens. The clinical relevance of sensitization testing in early life is therefore limited in the prediction of true allergy.

Sensitization rates to common inhaled allergens in Germany - increase and change patterns over the last 20 years

BACKGROUND

Sensitization rates to aeroallergens are rising worldwide. The prevalence is increasing, especially in Western countries. We aimed to investigate (1) sensitization rates and (2) cross-sensitization patterns in skin prick tests (SPTs) for the most relevant inhaled allergens in central Germany over 20 years, adjusted for regional pollen counts.

PATIENTS AND METHODS

This monocentric study evaluated SPTs for tree pollen, grass pollen and house dust mites (HDMs) in 4,315 patients (including children) with suspected airway allergies, from 1998-2017.

RESULTS

Sensitization rates to almost all aeroallergens have increased significantly over time, without relevant changes in regional pollen counts. Current sensitization rates in all our symptomatic patients were highest for grass (55.3 %) and rye pollen (59.6 %), with most pronounced increases in HDM sensitization over time (from 37.8 % to the current figure of 50.1 %). However, a low but consistent proportion of tree-sensitized patients (3.6-7.8 %) showed isolated positive SPTs to alder and/or hazel pollen without sensitization to birch pollen.

CONCLUSIONS

We demonstrate a significant rise in the total number of sensitized patients as well as increases in cross-sensitization between closely related allergens. Individuals with unusual mono-sensitization profiles to common inhaled allergens should be studied in more detail, since these patients are currently excluded from clinical trials for allergen immunotherapy.

Microfluidic methods for precision diagnostics in food allergy

Food allergy has reached epidemic proportions and has become a significant source of healthcare burden. Oral food challenge, the gold standard for food allergy assessment, often is not performed because it places the patient at risk of developing anaphylaxis. However, conventional alternative food allergy tests lack a sufficient predictive value. Therefore, there is a critical need for better diagnostic tests that are both accurate and safe. Microfluidic methods have the potential of helping one to address such needs and to personalize the diagnostics. This article first reviews conventional diagnostic approaches used in food allergy. Second, it reviews recent efforts to develop novel biomarkers and in vitro diagnostics. Third, it summarizes the microfluidic methods developed thus far for food allergy diagnosis. The article concludes with a discussion of future opportunities for using microfluidic methods for achieving precision diagnostics in food allergy, including multiplexing the detection of multiple biomarkers, sampling of tissue-resident cytokines and immune cells, and multi-organ-on-a-chip technology.

Does Provider Specialty Matter?

OBJECTIVES

Multiple practice guidelines discourage indiscriminate use of broad panels of allergen-specific IgE (sIgE) tests due to increased risk of false positives and misinterpretation of results. We provide an analytical framework to identify specialty-specific differences in ordering patterns and effectiveness, which can be used to improve test utilization.

METHODS

Test results from a tertiary pediatric hospital were analyzed by ordering specialty to evaluate size of allergen workups. Positivity rates were analyzed to determine effectiveness in selecting tests with high positive pretest probabilities. Laboratory test menu components were also evaluated.

RESULTS

Our findings demonstrate 29% of sIgE tests are ordered as part of broad workups (>20 sIgE tests/date of service) contrary to the recommended testing approach. Detailed descriptions of ordering patterns and positivity rates are provided.

CONCLUSIONS

This study provides a framework for using a cross-sectional analytical approach to assess test utilization patterns and evaluate components of laboratory testing menus.

Development of an effective sample transfer device for biomarker detection in nasal secretions

Nasal secretions (NS) reflect inflammatory activity of the nasal mucosa and thus can be utilized for disease diagnosis and determining treatment effects in Allergic rhinitis (AR). However, non-standardized collection of samples can affect the measured concentration of inflammatory biomarker in NS. In this study, we aimed to develop and evaluate new devices capable of standardizing the collection, storage, and preprocessing methods of NS samples. First, we chose the best swab as polyester (PE) and selected a stimulation method, twirling for 10 s at 1 Hz, to efficiently release AR biomarkers from a PE swab. Storage of sample solutions at -20 °C was optimal for the stability of biomarkers for the detection of AR. The new swab sample transfer device showed excellent concentration recovery efficiency (90-100%) for tryptase (Trp) and eosinophil cationic protein (ECP) without crosstalk between the two biomarkers. Finally, we compared the concentration of Trp in human NS samples of AR patients (n = 6) pre-processed by the new device with that by centrifuge as a standard method. As a result, the concentrations of Trp in NS were very similar in both groups. Therefore, this device can be utilized as an effective sample transfer and pre-processing device for point-of-care testing of AR.

Is atopic sensitization associated with indicators of early vascular ageing in adolescents?

Background

Chronic systemic inflammation accelerates early vascular ageing. Atopic sensitization and allergic diseases may involve increased inflammatory activity. This study aimed to assess whether atopic sensitization and allergic diseases were associated with altered vascular biomarkers in Norwegian adolescents.

Methods

Distensibility coefficient of the common carotid arteries, carotid intima-media thickness and atopic sensitization (serum total and specific IgEs) were assessed in 95 Norwegian adolescents, who participated in the RHINESSA generation study. Symptoms of allergic disease were assessed by an interviewer-led questionnaire.

Results

Atopic sensitization was found in 33 (34.7%) of the adolescents. Symptomatic allergic disease was found in 11 (33.3%) of those with atopic sensitization. Distensibility coefficient of the common carotid arteries appeared to be lower in participants with atopic sensitization than in those without (46.99±8.07*10⁻³/kPa versus 51.50±11.46*10⁻³/kPa; p>0.05), while carotid intima-media thickness did not differ between these groups (0.50±0.04mm versus 0.50±0.04mm; p>0.05). Crude, as well as age- and sex-adjusted multiple regression, revealed no significant association, neither of atopic sensitization nor of allergic disease, with distensibility coefficient of the common carotid arteries and carotid intima-media thickness.

Conclusions

Our results do not support the assumption of an adverse impact of atopic sensitization and/or allergic disease on distensibility coefficient of the common carotid arteries and carotid intima-media thickness in Norwegian adolescents. Further research is necessary to study whether the clinical severity of allergic diseases might be more important than the status of allergic disease or atopic sensitization.

To See or Not to See: A Systematic Review of the Importance of Human Ocular Surface Cytokine Biosignatures in Ocular Allergy

Cytokines are key cell signalling proteins in a number of immune and homeostatic pathways of the human body. In particular, they mediate intracellular mechanisms of allergy on the ocular surface by triggering cellular responses that result in typical physiological ocular allergy symptoms, such as itchiness, watery eyes, irritation, and swelling. Given the recent research focus in optometry on the aetiology of corneal ectasia subtypes like keratoconus, there is an increasing need for the development of new clinical diagnostic methods. An increasing trend is evident among recent publications in cytokine studies, whereby the concentrations of cytokines in healthy and disease states are compared to derive a specific cytokine profile for that disease referred to as ‘biosignatures’. Biosignatures have diagnostic applications in ocular allergy as a cheap, non-invasive alternative to current techniques like IgE antibody testing and skin prick tests. Cytokine detection from tear samples collected via microcapillary flow can be analysed either by enzyme-linked immunosorbent assays (ELISA), multiplex magnetic bead assays, or immunoblot assays. Characterising patient hypersensitivities through diagnostic tests is the first step to managing exposure to triggers. Investigating cytokine biosignatures in ocular allergy and their links to physiology are imperative and will be the focus of this systematic review article.

Association between sensitized to food allergens and childhood allergic respiratory diseases in Taiwan

BACKGROUND

Sensitization to allergen has long been known to be relate to childhood allergic diseases. Polysensitised children have more severe atopic diseases, whereas allergic rhinitis or asthma children with cosensitized to food and inhalant allergens were under-researched.

OBJECTIVE

To realize the association between sensitization to food allergens and pediatric allergic rhinitis and asthma in Taiwan.

METHODS

We included 138 participants with sensitized to allergen as assessed by serum-specific IgE. 87 of 138 participants had allergic rhinitis and 51 participants had asthma. All participants underwent a physical examination and measurement of serum total and specific IgE values. Besides, nasal peak expiratory flow rate (nPEFR) that was performed by the participants with allergic rhinitis and were requested to complete the Pediatric Rhinoconjunctivitis Quality of Life Questionnaires (PRQLQ). Lung function test and asthma control test (ACT)/child asthma control test (C-ACT) were performed by the participants with asthma.

RESULTS

39 of 87 allergic rhinitis participants with sensitized to food and inhalant allergens (AR food group), 48 of 87 allergic rhinitis participants with sensitized to inhalant allergen alone (AR inhalant group). The AR food group had significantly lower nPEFR values and higher total IgE values (p < 0.05) compared with the AR inhalant group. The AR food group had higher PRQLQ scores than the AR inhalant group. 24 of 51 asthma participants with sensitized to food and inhalant allergens (Asthma food group), 27 of 51 asthma participants with sensitized to inhalant allergen alone (Asthma inhalant group). The Asthma food group had significantly higher total IgE values (p < 0.05) compared with the Asthma inhalant group. The Asthma food group had lower lung function test values and asthma control test (ACT) scores than the other group.

CONCLUSIONS

Children with cosensitized to food and inhalant allergens have more severe clinical symptoms and abnormal laboratory findings. Sensitization to food allergen was more related to pediatric allergic rhinitis than asthma. We may need larger, longer and extended studies to confirm these findings.

Prevalence of food allergy among schoolchildren in Kuwait and its association with the coexistence and severity of asthma, rhinitis, and eczema: A cross-sectional study

BACKGROUND

Food allergy (FA) is a common public health problem that affects both children and adults. Empirical knowledge of the burden of FA in Kuwait is limited. This study sought to estimate the prevalence of FA among schoolchildren in Kuwait and assess associations between FA and the coexistence and severity of asthma, rhinitis, and eczema.

METHODS

Schoolchildren aged 11-14 years (n = 3,864) were enrolled in a cross-sectional study. Parents completed questionnaires regarding their children's early life exposures and clinical history of FA and allergic diseases. Study-defined FA was ascertained by a convincing clinical history. Associations were assessed using Poisson regression with robust variance estimation, and adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs) were estimated.

RESULTS

The 12-month prevalence of study-defined FA was estimated to be 4.1% (154/3,738), with more girls being affected than boys (aPR = 1.44, 95% CI: 1.04-1.99). Egg (2.7%), fish (1.6%), shellfish (1.3%), peanut (1.3%), and tree nut (1.2%) were the most reported offending food allergens. Underweight and adiposity, cesarean section delivery, exposure to household dogs during infancy, and parental history of doctor-diagnosed FA were associated with an increased prevalence of study-defined FA. However, later birth order was associated with a reduced prevalence of study-defined FA. The prevalence of eczema only was higher in children with study-defined FA than in those without study-defined FA (aPR = 3.49, 95% CI: 2.37-5.14). In contrast, this association was not pronounced for children who had asthma only (aPR = 1.56, 95% CI: 0.94-2.57) or rhinitis only (aPR = 1.40, 95% CI: 0.86-2.28). Study-defined FA was associated with a 9.20-fold (95% CI: 4.50-18.78) higher prevalence of coexisting asthma, rhinitis, and eczema. Moreover, study-defined FA was associated with increased severity of symptoms of asthma, rhinitis, and eczema.

CONCLUSIONS

FA affects a considerable proportion of schoolchildren in Kuwait, and the most reported offending food allergens are similar to those reported in Western countries. Study-defined FA was associated with the coexistence and increased severity of asthma, rhinitis, and eczema, indicating that FA may link the comanifestations of allergic diseases and contribute to their chronicity and severity.

Relation Between Attention-Deficit Hyperactivity Disorder and IgE-Dependent Allergy in Pediatric Patients

Food allergy is a common condition in children and adolescent, remitting with time. Few clinical studies have emphasized the link between food allergies and psychosocial conditions, suggesting a profound impact of atopic diseases on the development of attention-deficit hyperactivity disorder (ADHD) in children. The objective of this study was to compile and assess available studies on the comorbidity or causality between ADHD and atopic food allergy in children. We discuss epidemiology, interrelated mechanisms, and potential dietary interventions in the management of children with ADHD.

A Comprehensive Review on Kiwifruit Allergy: Pathogenesis, Diagnosis, Management, and Potential Modification of Allergens Through Processing

Kiwifruit is rich in bioactive components including dietary fibers, carbohydrates, natural sugars, vitamins, minerals, omega-3 fatty acids, and antioxidants. These components are beneficial to boost the human immune system and prevent cancer and heart diseases. However, kiwifruit is emerging as one of the most common elicitors of food allergies worldwide. Kiwifruit allergy results from an abnormal immune response to kiwifruit proteins and occur after consuming this fruit. Symptoms range from the oral allergy syndrome (OAS) to the life-threatening anaphylaxis. Thirteen different allergens have been identified in green kiwifruit and, among these allergens, Act d 1, Act d 2, Act d 8, Act d 11, and Act d 12 are defined as the "major allergens." Act d 1 and Act d 2 are ripening-related allergens and are found in abundance in fully ripe kiwifruit. Structures of several kiwifruit allergens may be altered under high temperatures or strong acidic conditions. This review discusses the pathogenesis, clinical features, and diagnosis of kiwifruit allergy and evaluates food processing methods including thermal, ultrasound, and chemical processing which may be used to reduce the allergenicity of kiwifruit. Management and medical treatments for kiwifruit allergy are also summarized.

Retrospective definition of reaction risk in Italian children with peanut, hazelnut and walnut allergy through component-resolved diagnosis

BACKGROUND

Serum IgE evaluation of peanut, hazelnut and walnut allergens through the use of component-resolved diagnosis (CRD) can be more accurate than IgE against whole food to associate with severe or mild reactions.

OBJECTIVES

The aim of the study was to retrospectively define the level of reaction risk in children with peanut, hazelnut and walnut sensitization through the use of CRD.

METHODS

34 patients [n=22 males, 65%; median age eight years, interquartile range (IQR) 5.0-11.0 years] with a reported history of reactions to peanut and/or hazelnut and/or walnut had their serum analyzed for specific IgE (s-IgE) by ImmunoCAP^® and ISAC^® microarray technique.

RESULTS

In children with previous reactions to peanut, the positivity of Arah1 and Arah2 s-IgE was associated with a history of anaphylaxis to such food, while the positivity of Arah8 s-IgE were associated with mild reactions. Regarding hazelnut, the presence of positive Cora9 and, particularly, Cora14 s-IgE was associated with a history of anaphylaxis, while positive Cora1.0401 s-IgE were associated with mild reactions. Concerning walnut, the presence of positive Jug r 1, Jug r 2, Jug r 3 s-IgE was associated with a history of anaphylaxis to such food. ImmmunoCAP^® proved to be more useful in retrospectively defining the risk of hazelnut anaphylaxis, because of the possibility of measuring Cor a14 s-IgE.

CONCLUSIONS

Our data show that the use of CRD in patients with allergy to peanut, hazelnut and walnut could allow for greater accuracy in retrospectively defining the risk of anaphylactic reaction to such foods.

Allergen-specific IgE and IgG4 patterns among patients with different allergic diseases

Background

In addition to allergen-specific IgE (sIgE), allergen-specific IgG4 (sIgG4) antibodies are also involved in the immune response resulting from an allergen exposure. The aim of our study was to analyze sIgE and sIgG4 patterns in the most common allergic disorders: bronchial asthma, upper airway disorders and atopic dermatitis.

Methods

In this study a screening analysis of blood serum samples from 673 patients aged from 6 months to 17 years with different allergic entities was performed on microarrays. sIgE and sIgG4 levels to the most common allergens were estimated.

Results

sIgE response to most pollen allergens is more strongly associated with respiratory diseases than with atopic dermatitis, while sIgE responses to cat and dog dander are more strongly associated with bronchial asthma than with atopic dermatitis and upper airway disorders such as rhinosinusitis and allergic rhinitis. A lower prevalence of sIgG4 to pollen allergens in cases of atopic dermatitis is observed compared with that in cases of asthma and upper airway disorders. Analyzing all the allergic disorders, one can see that sIgG4 response to inhalant allergens is strongly associated with sensitization to the corresponding allergen.

Conclusion

Allergen-specific IgE and IgG4 patterns that are relevant to concrete allergic diseases differ by sIgE and sIgG4 prevalences to defined allergens.

Electronic supplementary material

The online version of this article (10.1186/s40413-018-0220-5) contains supplementary material, which is available to authorized users.

Single and multiple food allergies in infants with proctocolitis

BACKGROUND

Food protein-induced allergic proctocolitis is a frequent cause of rectal bleeding in infants. Characteristics of infants with multiple food allergies have not been defined.

OBJECTIVE

This study aimed to identify characteristics of infants with proctocolitis and compare infants with single and multiple food allergies.

METHODS

A total of 132 infants with proctocolitis were evaluated retrospectively. All of the infants were diagnosed by a paediatric allergist and/or a paediatric gastroenterologist according to guidelines. Clinical features of the infants, as well as results of a complete blood count, skin prick test, specific immunoglobulin E, and stool examinations or colonoscopy were recorded.

RESULTS

Cow's milk (97.7%) was the most common allergen, followed by egg (22%). Forty-five (34.1%) infants had allergies to more than one food. Infants with multiple food allergies had a higher eosinophil count (613±631.2 vs. 375±291.9) and a higher frequency of positive specific IgE and/or positive skin prick test results than that of patients with a single food allergy. Most of the patients whose symptoms persisted after two years of age had multiple food allergies.

CONCLUSIONS

There is no difference in clinical presentations between infants with single and multiple food allergies. However, infants with multiple food allergies have a high blood total eosinophil count and are more likely to have a positive skin prick test and/or positive specific IgE results.

A selective and sensitive nanosensor for fluorescent detection of specific IgEs to purified allergens in human serum

Food allergies are increasingly recognized as a major healthcare concern. In order to sensitively and specifically detect allergies from blood samples of at-risk allergic patients, an effective magnetic fluorescence sensing platform (EMFP) was constructed. The EMFP incorporated hollow mesoporous silica nanospheres (HMNs) to amplify signal from the target IgE in addition to magnetic nanoparticles (MNPs) to capture and separate the target IgE. The application of EMFP to immunoassays indicated a detection limit of 0.0159 ng mL⁻¹ for low concentration specific immunoglobulin E (sIgE) against purified shellfish Metapenaeus ensis (Meta. E.) allergens, which is 15 fold more sensitive than the commercially available Food and Drug Administration-approved analyzers. Notably, EMFP was specific for the targeted sIgE even with interference by other sIgEs. In addition, the detection time is only 75 min, considerably faster than current commercial ELISA kits for IgE assays. Together, these results demonstrated that EMFP has excellent sensitivity and selectivity for the rapid detection of sIgE. The method thus exhibits potential toward the rapid monitoring of sIgE against Meta. E. allergens in clinical application.

The effective magnetic fluorescence sensing platform was employed to amplify signal and capture target IgE in one step.

The Allergist's Role in Anaphylaxis and Food Allergy Management in the School and Childcare Setting

Anaphylaxis and food allergy management in childcare facilities and schools are growing challenges. An increasing number of children experience severe allergic reactions on school grounds as evidenced by reports of epinephrine use. Data also suggest that the prevalence of food allergy may be increasing, with a large percentage of school-aged children at risk for anaphylaxis. Moreover, anaphylaxis may occur for the first time in a previously undiagnosed child at school or childcare setting, suggesting that general preparedness is essential. Management includes strategies for minimizing the risk of reactions and allergen exposures as well as readiness to recognize and treat allergic reactions of any severity. The primary objective of this report is to offer health care providers an overview of relevant evidence, resources, and expert opinion to assist with developing interprofessional collaborative counsel on school food allergy management and anaphylaxis preparedness with families, schools, and childcare settings. We present the current evidence base, suggest resources, and highlight areas of current controversy that warrant further study.

Prostaglandin D2 metabolite in urine is an index of food allergy

Food allergy is immediate hypersensitive reactions to ingested foods. Since early diagnosis is effective for disease control, development of an objective diagnostic index is required. Using mediator-lipidomics, we found that levels of the urinary prostaglandin D₂ (PGD₂) metabolite, tetranor-PGDM, reflected the severity of the allergic symptoms and intestinal mast cell hyperplasia in mice. Repeated oral challenges with ovalbumin promoted allergic symptoms in sensitized mice. Particularly, the allergic mice presented with increased numbers of intestinal mast cells, which strongly expressed hematopoietic PGD synthase (H-PGDS). The levels of urinary tetranor-PGDM increased as the disease progressed. Treatment with a mast cell inactivator or an anti-inflammatory steroid attenuated these symptoms and decreased the tetranor-PGDM urinary levels. The levels of urinary tetranor-PGDM did not correlate with the disease severity in murine models of colitis, asthma, or allergic dermatitis. Furthermore, we have shown that urinary levels of tetranor-PGDM were significantly higher in patients with food allergy than those in healthy volunteers and patients with other types of allergic diseases such as asthma, allergic rhinitis, and atopic dermatitis. These findings suggest that urinary tetranor-PGDM is a useful diagnostic index of food allergy in both mice and humans.

Food Challenge and Community-Reported Reaction Profiles in Food-Allergic Children Aged 1 and 4 Years: A Population-Based Study

BACKGROUND

Oral food challenge is the main tool for diagnosing food allergy, but there is little data on the reaction profiles of young children undergoing challenges, nor how these reactions compare to reactions on accidental ingestion in the community.

OBJECTIVES

To compare reaction profiles from food challenges and parent-reported reactions on accidental ingestion, and assess predictors of severe reactions.

METHODS

HealthNuts is a longitudinal population-based cohort study of 5276 1-year-old infants. Infants underwent skin prick tests and those with identifiable wheals were offered food challenges. Food challenges were repeated at age 4 years in those with previous food allergy or reporting new food allergies. Community-reported reactions were ascertained from parent questionnaires.

RESULTS

Food challenges were undertaken in 916 children at age 1 year and 357 children at age 4 years (a total of 2047 peanut, egg, or sesame challenges). Urticaria was the most common sign in positive challenges at both ages (age 1 year, 88.7%, and age 4 years, 71.2%) although angioedema was significantly more common at age 4 years (40.1%) than at age 1 year (12.9%). Anaphylaxis was equally uncommon at both ages (2.1% and 2.8% of positive challenges at ages 1 and 4 years, respectively) but more common for peanut than for egg (4.5% and 1.2% of positive challenges at ages 1 and 4 years, respectively). The patterns of presenting signs reported during community reactions were similar to those observed in formal food challenges. Serum food-specific IgE levels of 15 kU/L or more were associated with moderate to severe reactions but skin prick test was not.

CONCLUSIONS

There was a shift from the most common presenting reaction of urticaria during food challenges toward more angioedema in older children. Serum food-specific IgE levels were associated with reaction severity.

Critical Issues in Food Allergy: A National Academies Consensus Report

The National Academies of Sciences, Engineering, and Medicine convened an expert, ad hoc committee to examine critical issues related to food allergy. The authors of the resulting report, "Finding a Path to Safety in Food Allergy: Assessment of the Global Burden, Causes, Prevention, Management, and Public Policy," evaluated the scientific evidence on the prevalence, diagnosis, prevention, and management of food allergy and made recommendations to bring about a safe environment for those affected. The committee recommended approaches to monitor prevalence, explore risk factors, improve diagnosis, and provide evidence-based health care. Regarding diagnostics, emphasis was placed on utilizing allergy tests judiciously in the context of the medical history because positive test results are not, in isolation, diagnostic. Evidence-based prevention strategies were advised (for example, a strategy to prevent peanut allergy through early dietary introduction). The report encourages improved education of stakeholders for recognizing and managing as well as preventing allergic reactions, including an emphasis on using intramuscular epinephrine promptly to treat anaphylaxis. The report recommends improved food allergen labeling and evaluation of the need for epinephrine autoinjectors with a dosage appropriate for infants. The committee recommended policies and guidelines to prevent and treat food allergic reactions in a various settings and suggested research priorities to address key questions about diagnostics, mechanisms, risk determinants, and management. Identifying safe and effective therapies is the ultimate goal. This article summarizes the key findings from the report and emphasizes recommendations for actions that are applicable to pediatricians and to the American Academy of Pediatrics.

Is a Positive Developmental-Behavioral Screening Score Sufficient to Justify Referral? A Review of Evidence and Theory

In their recommendations on screening for autism and developmental disabilities, the American Academy of Pediatrics recommends referral subsequent to a positive screening result. In this article, we argue that positive screening results are not always sufficient to justify a referral. We show that although positive predictive values are often low, they actually overstate the probability of having a disorder for many children who screen positive. Moreover, recommended screening thresholds are seldom set to ensure that the benefits of referral will equal or exceed the costs and risk of harm, which is a necessary condition for an optimal threshold in decision analysis. Drawing on recent recommendations for the Institute of Medicine/National Academy of Medicine, we discuss the implications of this argument for pediatric policy, education, and practice. In particular, we recommend that screening policies be revised to ensure that the costs and benefits of actions recommended in the event of a positive screen are appropriate to the screening threshold. We recommend greater focus on clinical decision-making in the education of physicians, including shared decision-making with patients and their families. Finally, we recommend broadening the scope of screening research to encompass not only the accuracy of specific screening instruments, but also their ability to improve decision-making in the context of systems of care.

Allergic Rhinitis

Among the atopic disorders, allergic rhinitis is the most prevalent. Patients who suffer from allergic rhinitis sustain significant morbidity and loss of productivity. Cardinal symptoms include nasal congestion, rhinorrhea, sneezing, and nasal itching, although multiple related symptoms may occur. Causes should be ruled out with a thorough history and physical examination, with particular attention to red flag or atypical symptoms. Skin testing or serum sampling can confirm diagnosis and also guide therapy. Therapy is multimodal, tailored to a particular patient's symptom burden and quality of life.

Assessment of endogenous allergenicity of genetically modified plants exemplified by soybean - Where do we stand?

According to EU regulation, genetically modified (GM) plants considered to be allergenic have to be assessed concerning their endogenous allergens before placement on the EU market, in line with the international standards described in Codex Alimentarius. Under such premises, a quantitative relevant increase in allergens might occur in GM plants as an unintended effect compared with conventionally produced crops, which could pose a risk to consumers. Currently, data showing a connection between dose and allergic sensitisation are scarce since the pathophysiological mechanisms of sensitisation are insufficiently understood. In contrast, data on population dose-distribution relationships acquired by oral food challenge are available showing a connection between quantity of allergenic protein consumed and the population of allergic individuals experiencing reactions. Soybean is currently the only recognised allergenic GM food by law for which EFSA has received applications and was therefore taken as an example for defining an assessment strategy. Identification of potential allergens, methodology for quantification as well as risk assessment considerations, are discussed. A strategy is proposed for the identification, assessment and evaluation of potential hazards/risks concerning endogenous allergenicity in food derived from plants developed by biotechnology. This approach could be expanded to other allergenic foods in the future, whenever required.

Selling falsehoods? A cross-sectional study of Canadian naturopathy, homeopathy, chiropractic and acupuncture clinic website claims relating to allergy and asthma

OBJECTIVE

To identify the frequency and qualitative characteristics of marketing claims made by Canadian chiropractors, naturopaths, homeopaths and acupuncturists relating to the diagnosis and treatment of allergy and asthma.

DESIGN

Cross-sectional study.

SETTING

Canada.

DATA SET

392 chiropractic, naturopathic, homeopathic and acupuncture clinic websites located in 10 of the largest metropolitan areas in Canada, as identified using 400 Google search results. Duplicates were not excluded from data analysis.

MAIN OUTCOME MEASURES

Mention of allergy, sensitivity or asthma, claim of ability to diagnose allergy, sensitivity or asthma, claim of ability to treat allergy, sensitivity or asthma, and claim of allergy, sensitivity or asthma treatment efficacy. Tests and treatments promoted were noted as qualitative examples.

RESULTS

Naturopath clinic websites have the highest rates of advertising at least one of diagnosis, treatment or efficacy for allergy or sensitivity (85%) and asthma (64%), followed by acupuncturists (68% and 53%, respectively), homeopaths (60% and 54%) and chiropractors (33% and 38%). Search results from Vancouver, British Columbia were most likely to advertise at least one of diagnosis, treatment or efficacy for allergy or sensitivity (72.5%) and asthma (62.5%), and results from London, Ontario were least likely (50% and 40%, respectively). Of the interventions advertised, few are scientifically supported; the majority lack evidence of efficacy, and some are potentially harmful.

CONCLUSIONS

The majority of alternative healthcare clinics studied advertised interventions for allergy and asthma. Many offerings are unproven. A policy response may be warranted in order to safeguard the public interest.

Indoor Environmental Control Practices and Asthma Management

Indoor environmental exposures, particularly allergens and pollutants, are major contributors to asthma morbidity in children; environmental control practices aimed at reducing these exposures are an integral component of asthma management. Some individually tailored environmental control practices that have been shown to reduce asthma symptoms and exacerbations are similar in efficacy and cost to controller medications. As a part of developing tailored strategies regarding environmental control measures, an environmental history can be obtained to evaluate the key indoor environmental exposures that are known to trigger asthma symptoms and exacerbations, including both indoor pollutants and allergens. An environmental history includes questions regarding the presence of pets or pests or evidence of pests in the home, as well as knowledge regarding whether the climatic characteristics in the community favor dust mites. In addition, the history focuses on sources of indoor air pollution, including the presence of smokers who live in the home or care for children and the use of gas stoves and appliances in the home. Serum allergen-specific immunoglobulin E antibody tests can be performed or the patient can be referred for allergy skin testing to identify indoor allergens that are most likely to be clinically relevant. Environmental control strategies are tailored to each potentially relevant indoor exposure and are based on knowledge of the sources and underlying characteristics of the exposure. Strategies include source removal, source control, and mitigation strategies, such as high-efficiency particulate air purifiers and allergen-proof mattress and pillow encasements, as well as education, which can be delivered by primary care pediatricians, allergists, pediatric pulmonologists, other health care workers, or community health workers trained in asthma environmental control and asthma education.

Age, sex and the association between skin test responses and IgE titres with asthma

BACKGROUND

Skin prick tests (SPTs) and allergen-specific serum IgE (sIgE) measurements are the main diagnostic tools for confirming atopic sensitization. Results are usually reported as 'positive' or 'negative', using the same arbitrary cut-offs (SPT>3 mm, sIgE>0.35 kUA /l) across different ages and sexes. We investigated the influence of age and sex on the interpretation of allergy test in the context of childhood asthma.

METHODS

In a population-based birth cohort (n = 1051), we ascertained the information on asthma/wheeze (validated questionnaires) and performed SPTs and sIgE measurement to inhalant allergens (dust mite, cat, dog) at follow-ups between ages three and 11 years. We investigated the association between quantitative sensitization (sum of SPT mean wheal diameters [MWD] and sIgE titres to the three allergens) and current wheeze and asthma across ages and sexes.

RESULTS

We observed a significant association between the SPT MWD and sIgE titres and wheeze/asthma at most ages and for both sexes. However, the strength of this association was age- and sex-dependent. For SPTs, the strength of the association between MWD and asthma increased with increasing age; we observed the opposite pattern for sIgE titre. For any given SPT MWD/sIgE titre, boys were significantly more likely to express clinical symptoms, particularly in early life; this difference between males and females diminished with age and was no longer significant by age 11 years.

CONCLUSIONS

Age and sex should be taken into account when interpreting the results of skin tests and sIgE measurement, and age- and sex-specific normative data are needed for these allergy tests.

Relationship between respiratory and food allergy and evaluation of preventive measures

Food allergy and respiratory allergy are two frequently associated diseases and with an increasing prevalence. Several reports show the presence of respiratory symptoms in patients with food allergy, while certain foods may be related to the development or exacerbation of allergic rhinitis and asthma. The present update focuses on this relationship, revealing a pathogenic and clinical association between food and respiratory allergy. This association is even more intense when the food hypersensitivity is persistent or starts in the early years of life. Food allergy usually precedes respiratory allergy and may be a risk factor for allergic rhinitis and asthma, becoming a relevant clinical marker for severe atopic asthma. Furthermore, the presence of co-existing asthma may enhance life-threatening symptoms occurring during a food allergic reaction. Recommendations for dietary restrictions during pregnancy and breastfeeding to prevent the development of respiratory allergy are controversial and not supported by consistent scientific data. Current recommendations from medical societies propose exclusive breastfeeding during the first four months of life, with the introduction of solid food in the fourth to the seventh month period of life. A delayed introduction of solid food after this period may increase the risk of developing subsequent allergic conditions. Further studies are encouraged to avoid unjustified recommendations involving useless dietary restrictions.