Standard skin prick testing and sensitization to inhalant allergens across Europe--a survey from the GALEN network

Factors associated with sensitisation to selected aero-allergens in children and adolescents with asthma followed up at Laquintinie Hospital Douala, Cameroon

INTRODUCTION

In spite of the substantial impact of pediatric asthma on healthcare resources, there is a notable dearth of research focusing on allergen sensitization specifically in children and adolescents with asthma in Cameroon, with existing studies primarily concentrating on adult populations. We, therefore, set out to determine factors associated with sensitization to selected aero-allergens in children and adolescents with asthma followed up at Laquintinie Hospital Douala, Cameroon.

METHODOLOGY

We conducted a cross-sectional analytical study on patients aged 2-17 years followed up for pediatric asthma at Laquintinie Hospital Douala for 8 months (January to August 2023). Skin prick tests were performed using selected standardized aeroallergens extracts. Factors associated with sensitization were determined using multivariable logistic regression analysis. The threshold for significance was set at p < .05.

RESULTS

In total, 126 children and adolescents with asthma were recruited, 50.79% of whom were male with an average age of 8.00 ± 3.99 years. Eight out of 10 patients (83.52%) were sensitized to common aero-allergens (20.59% monosensitized and 79.41% polysensitized). The most common aero-allergens found were the dust mites Dermatophagoïdes pteronyssinus (81.37%), Blomia tropicalis (67.64%) and Dermatophagoïdes farinae (52.94%) followed by Blatella species (25.49%). The factors independently associated with sensitization in our population were the personal history of allergic rhinitis in the patient [adjusted odds ratio, aOR: 4.07 (95% confidence interval, CI: 1.41-11.76), b = 0.54, p = .009], chest tightness at rest [aOR: 5.92 (95% CI: 1.08-32.38), b = 0.87, p = .040), and age above 5 years [aOR: 4.65 (95% CI: 1.47-14.69), b = 0.59, p = .009).

CONCLUSION

Sensitization to multiple aeroallergens is common in children and adolescents with asthma, especially for dust mites and cockroaches. Factors associated with sensitization are patients aged >5 years, chest tightness at rest, and a personal history of allergic rhinitis.

Allergy to fungi: Advances in the understanding of fungal allergens

Allergic diseases are a major health problem due to their increasing incidence and high prevalence worldwide. Asthma has several aetiologies, and allergy plays an important role in its development in approximately 60% of adults and 80% of children and adolescents. Although the link between aeroallergen sensitization and asthma exacerbations has been long recognized, the investigations of the triggering allergens may be superficial in many asthma cases. The main allergenic sources related to asthma, and other allergic diseases, are pollens, mites, fungi, and animal epithelia. Fungi are considered the third most frequent cause of respiratory pathologies. Asthma caused by several fungi species may have a bad prognosis in some cases due to its severity and difficulty in avoidance methods. Despite the recognised relevance of fungi in respiratory allergies, the knowledge about fungal allergens seems to be scarce, with few descriptions of new allergens, compared to other allergenic sources. The study of major, minor, and cross-reactive fungal allergens, and their relevance in the allergic disease, might be crucial, not only to accurately diagnose these allergies, but also to predict exacerbations and responses to therapies, as well as for the development of personalized treatment plans in a fast-changing climate scenario.

[Allergenic and chemical pollutants of indoor environments and asthma: Characterization, assessment and eviction]

The environment of an asthmatic patient can contain numerous sources of pollutants that degrade the quality of indoor air and have major repercussions on the occurrence and control of asthma. Assessment and improvement of the quality of indoor air should be assigned a major role in pneumology and allergology consultations. Characterization of an asthmatic's environment entails a search for biological pollutants with mite allergens, mildew, and allergens resulting from the proximity of pets. It is important to evaluate the chemical pollution represented by exposure to volatile organic compounds, which are increasingly present in our lodgings. Active or second-hand smoking must in all circumstances be sought out and quantified. Assessment of the environment is mediated by several methods, of which the application depends not only on the pollutant sought out, but also on enzyme-linked immunosorbent assay (ELISA), which has an essential role in quantification of biological pollutants. Attempts at expulsion of the different indoor environment pollutants is mediated by indoor environment advisors, whose efforts are aimed at obtaining reliable evaluation and control of indoor air. Implemented as a form of tertiary prevention, their methods are conducive to improved asthma control, in adults as well as children.

Changes of allergic inflammation and immunological parameters after Alt a 1 and A. alternata immunotherapy in mice

Background

The efficacy of allergen-specific subcutaneousimmunotherapy (SCIT) with Alt a 1 of the fungus A. alternata is still unknown. Yet, few studies compare the therapeutic effects and immunological mechanisms of Alt a 1 and A. alternata extracts. We aim to explore and compare the changes in allergic inflammation and immunological mechanisms of Alt a 1 and A. alternata in mice.

Methods

Female BALB/c mice administrated recombinant Alt a 1 (rAlt a 1), native Alt a 1 (nAlt a 1), and A. alternata. Lung histology, airway hyper-reactivity (AHR), bronchoalveolar lavage fluid (BALF) cytokine levels, serum immunoglobulin responses, the expression of Bcl-6, the percentages of T follicular helper cells (Tfh), cytokine-related Tfh subtypes, regulatory B cells (Breg), and IL-10+ Breg cells were detected.

Results

High-purity nAlt 1 protein was obtained. SCIT with Alt a 1 and Alternaria decreased airway and lung inflammation, including improvement of lung pathology, lower levels of AHR, reduction of total cell numbers, and IL-4 and IL-13 levels in BALF. Furthermore, Alt a 1-SCIT effectively suppressed the IgE responses, elevated IgG titers, and was superior in decreasing the expression of Bcl-6. Additionally, Alternaria-SCIT significantly decreased the expression of Tfh cells, L-4+ Tfh, and IL-5+ Tfh cells in the spleen, whereas Alt a 1 showed superior therapeutic effects in the lymph node. IL-13+ Tfh cells in these two treatment groups not being significant. IL-17A+ Tfh cells were alleviated most effectively after A. alternata-SCIT in both the spleen and lymph node. Intriguingly, IL-10+ Breg cells decreased remarkably in response to SCIT with rAlt a 1.

Conclusions

Treatments with Alt a 1 and A. alternata extracts had beneficial effects on allergic inflammation. Alt a 1-SCIT resulted in prominent improvement in the immunoglobulin responses, Bcl-6, and IL-10+ Breg cells. Alternaria-SCIT was more likely to suppress the expression of Tfh and cytokine-related Tfh subtypes.

Aspergillus Conidia and Allergens in Outdoor Environment: A Health Hazard?

Aspergillus is a genus of saprophytic fungus widely distributed in the environment and associated with soil, decaying vegetation, or seeds. However, some species, such as A. fumigatus, are considered opportunistic pathogens in humans. Their conidia (asexual spores) and mycelia are associated with clinical diseases known as invasive aspergillosis (IA), mainly related to the respiratory tract, such as allergic asthma, allergic bronchopulmonary aspergillosis (ABPA), or hypersensitivity. However, they can also disseminate to other organs, particularly the central nervous system. Due to the dispersal mechanism of the conidia through the air, airborne fungal particle measurement should be used to prevent and control this mold. This study aims to measure the outdoor airborne concentration of Aspergillus conidia and the Asp f 1 allergen concentration in Bellaterra (Barcelona, Spain) during 2021 and 2022, and to compare their dynamics to improve the understanding of the biology of this genus and contribute to a better diagnosis, prevention, and therapeutic measures in the face of possible health problems. The results show that both particles were airborne nearly all year round, but their concentrations showed no correlation. Due to Asp f 1 not being present in the conidia itself but being detectable during their germination and in hyphal fragments, we report the relevance of the aero-immunological analysis as a methodology to detect the potential pathogenic hazard of this fungus.

Going over Fungal Allergy: Alternaria alternata and Its Allergens

Fungal allergy is the third most frequent cause of respiratory pathologies and the most related to a poor prognosis of asthma. The genera Alternaria and Cladosporium are the most frequently associated with allergic respiratory diseases, with Alternaria being the one with the highest prevalence of sensitization. Alternaria alternata is an outdoor fungus whose spores disseminate in warm and dry air, reaching peak levels in temperate summers. Alternaria can also be found in damp and insufficiently ventilated houses, causing what is known as sick building syndrome. Thus, exposure to fungal allergens can occur outdoors and indoors. However, not only spores but also fungal fragments contain detectable amounts of allergens and may function as aeroallergenic sources. Allergenic extracts of Alternaria hyphae and spores are still in use for the diagnosis and treatment of allergic diseases but are variable and insufficiently standardised, as they are often a random mixture of allergenic ingredients and casual impurities. Thus, diagnosis of fungal allergy has been difficult, and knowledge about new fungal allergens is stuck. The number of allergens described in Fungi remains almost constant while new allergens are being found in the Plantae and Animalia kingdoms. Given Alt a 1 is not the unique Alternaria allergen eliciting allergy symptoms, component-resolved diagnosis strategies should be applied to diagnose fungal allergy. To date, twelve A. alternata allergens are accepted in the WHO/IUIS Allergen Nomenclature Subcommittee, many of them are enzymes: Alt a 4 (disulfide isomerase), Alt a 6 (enolase), Alt a 8 (mannitol de-hydrogenase), Alt a 10 (aldehyde dehydrogenase), Alt a 13 (glutathione-S-transferase) and Alt a MnSOD (Mn superoxide dismutase), and others have structural and regulatory functions such as Alt a 5 and Alt a 12, Alt a 3, Alt a 7. The function of Alt a 1 and Alt a 9 remains unknown. Other four allergens are included in other medical databases (e.g., Allergome): Alt a NTF2, Alt a TCTP, and Alt a 70 kDa. Despite Alt a 1 being the A. alternata major allergen, other allergens, such as enolase, Alt a 6 or MnSOD, Alt a 14 have been suggested to be included in the diagnosis panel of fungal allergy.

[The impact of specialized management on allergic asthma outcomes]

INTRODUCTION

Allergic asthma has variable characteristics depending on the region of occurrence. Management is often organized without easy access to a specialized pneumo-allergological evaluation.

OBJECTIVES

PRIMARY: To characterize allergic asthma in patients followed at the Nancy University Hospital.

SECONDARY

To estimate the impact at 12 months of the proposed specialized management.

METHOD

Retrospective study including allergic asthmatic adults conducted between 01/01/2016 and 31/12/2018. Parameters studied (aside from descriptive parameters): asthma control score ACQ-7 (Asthma Control Questionnaire) and lung function at inclusion and at one year.

RESULTS

One hundred and fifteen patients were included (age 42±16 years, women 63%, non-smokers 70%). Even though asthma symptoms arose at 19±18 years, the specialized consultation was performed 21±17.5 years later. Frequent sensitizations involved house dust mites (49%), cat dander (43%), grasses (43%). Patients tended to underestimate the frequency of their allergies (mites 36% P=0.011, pollens 36% P=0.001, pet dander 42% P=0.003, molds 80% P=0.007). At 1-year follow-up both the ACQ-7 score (1.3±1.3 vs. 0.8±0.9; P=0.007) and the forced expiratory volume per second (81.3±20.8% vs. 86.2±21.9%; P=0.002) had improved.

CONCLUSION

The specificities of allergic asthmatics followed up in Nancy: late age of asthma onset of asthma and specialized consultation; predominant sensitization to cat dander and Betulaceae pollens; underestimation of allergies by the patient. Specialized care seems to important in the management of allergic asthma. While access to specialized care remains problematic, it could be facilitated by the creation of dedicated networks.

Relationship between IgE Levels Specific for Ragweed Pollen Extract, Amb a 1 and Cross-Reactive Allergen Molecules

Ragweed (Ambrosia artemisiifolia) pollen is a major endemic allergen source responsible for severe allergic manifestations in IgE-sensitized allergic patients. It contains the major allergen Amb a 1 and cross-reactive allergen molecules, such as the cytoskeletal protein profilin, Amb a 8 and calcium-binding allergens Amb a 9 and Amb a 10. To assess the importance of Amb a 1, profilin and calcium-binding allergen, the IgE reactivity profiles of clinically well-characterized 150 ragweed pollen-allergic patients were analysed regarding specific IgE levels for Amb a 1 and cross-reactive allergen molecules by quantitative ImmunoCAP measurements, IgE ELISA and by basophil activation experiments. By quantifying allergen-specific IgE levels we found that Amb a 1-specific IgE levels accounted for more than 50% of ragweed pollen-specific IgE in the majority of ragweed pollen-allergic patients. However, approximately 20% of patients were sensitized to profilin and the calcium-binding allergens, Amb a 9 and Amb a 10, respectively. As shown by IgE inhibition experiments, Amb a 8 showed extensive cross-reactivity with profilins from birch (Bet v 2), timothy grass (Phl p 12) and mugwort pollen (Art v 4) and was identified as a highly allergenic molecule by basophil activation testing. Our study indicates that molecular diagnosis performed by the quantification of specific IgE to Amb a 1, Amb a 8, Amb a 9 and Amb a 10 is useful to diagnose genuine sensitization to ragweed pollen and to identify patients who are sensitized to highly cross-reactive allergen molecules present in pollen from unrelated plants, in order to enable precision medicine-based approaches for the treatment and prevention of pollen allergy in areas with complex pollen sensitization.

Worsening of asthma control after COVID-19

Background

SARS-CoV-2 enters lung cells via angiotensin-converting enzyme 2 (ACE2) receptor. Several studies suggest that interleukin-13, an important cytokine involved in T2 inflammation, reduces ACE2 expression, and therefore, asthma would not be a significant risk factor for the development of severe COVID-19. However, several asthma-related risk factors should be valued during the concurrent occurrence of asthma and COVID-19. The purpose of this study was to compare the evolution of asthma in patients who had COVID-19 with those who did not have the disease.

Methods

This was an observational and retrospective study involving asthmatic patients followed up at a tertiary center. Patients were assessed for severity of asthma, atopy, comorbidities, and COVID-19. Worsening of asthma was considered when, during the period of Sept 2020 to Oct 2021, patients referred an increasing of asthma symptoms and a need to increment their maintenance therapy.

Results

This study included 208 asthmatic patients, the mean age was 52.75 years, 79.81% were atopic asthmatics, and 59 (28.37%) had laboratory-confirmed coronavirus disease. Of all patients infected with the SARS-CoV-2, eleven (18.64%) needed hospitalization and required oxygen supply with an O2 mask. Comparing the worsening of asthma between patients who had COVID-19 and those who had not the disease, there was a statistically significant difference, 33.90 vs. 11.41%, respectively (p &lt; 0.001). There was no statistical significance regarding asthma comorbidities.

Conclusion

This study assessed a group of asthmatic patients that had COVID-19, and that although the respiratory symptoms related to COVID-19 were mild to moderate, a subgroup of these asthmatic patients evolved with a chronic worsening of their asthma requiring an increment in asthma medication to control the disease.

A comprehensive aerobiological study of the airborne pollen in the Irish environment

Respiratory allergies triggered by pollen allergens represent a significant health concern to the Irish public. Up to now, Ireland has largely refrained from participating in long-term aerobiological studies. Recently, pollen monitoring has commenced in several sampling locations around Ireland. The first results of the pollen monitoring campaigns for Dublin (urban) and Carlow (rural) concerning the period 2017-2019 and 2018-2019, respectively, are presented herein. Additional unpublished pollen data from 1978-1980 and, 2010-2011 were also incorporated in creating the first pollen calendar for Dublin. During the monitoring period over 60 pollen types were identified with an average Annual Pollen Integral (APIn) of 32,217 Pollen × day/m³ for Dublin and 78,411 Pollen × day/m³ for Carlow. The most prevalent pollen types in Dublin were: Poaceae (32%), Urticaceae (29%), Cupressaceae/Taxaceae (11%), Betula (10%), Quercus (4%), Pinus (3%), Fraxinus (2%), Alnus (2%) and Platanus (1%). The predominant pollen types in Carlow were identified as Poaceae (70%), Urticaceae (12%), Betula (10%), Quercus (2%), Fraxinus (1%) and Pinus (1%). These prevalent pollen types increased in annual pollen concentration in both locations from 2018 to 2019 except for Fraxinus. Although higher pollen concentrations were observed for the Carlow (rural) site a greater variety of pollen types were identified for the Dublin (urban) site. The general annual trend in the pollen season began with the release of tree pollen in early spring, followed by the release of grass and herbaceous pollen which dominated the summer months with the annual pollen season coming to an end in October. This behaviour was illustrated for 21 different pollen types in the Dublin pollen calendar. The correlation between ambient pollen concentration and meteorological parameters was also examined and differed greatly depending on the location and study year. A striking feature was a substantial fraction of the recorded pollen sampled in Dublin did not correlate with the prevailing wind directions. However, using non-parametric wind regression, specific source regions could be determined such as Alnus originating from the Southeast, Betula originating from the East and Poaceae originating from the Southwest.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10453-022-09751-w.

Study of Cat Allergy Using Controlled Methodology-A Review of the Literature and a Call to Action

The prevalence of cat allergen-induced AR is increasing worldwide, prompting its study using controlled methodology. Three general categories of allergen exposure models currently exist for the study of cat allergen-induced AR: natural exposure cat rooms, allergen exposure chambers (AEC), and nasal allergen challenges (NAC). We evaluated existing literature surrounding the use of these models to study cat allergen induced AR using online research databases, including OVID Medline, Embase, and Web of Science. We report that natural exposure cat rooms have been important in establishing the foundation for our understanding of cat allergen-induced AR. Major limitations, including variable allergen ranges and differing study designs highlight the need for a more standardized protocol. In comparison, AECs are an exceptional model to mimic real-world allergen exposure and study long-term implications of AR with large sample sizes. Existing AECs are limited by heterogeneous facility designs, differing methods of cat allergen distribution, and issues surrounding cost and accessibility. Conversely, NACs allow for smaller participant cohorts for easier biological sampling and are ideal for phase I, phase 2 or proof-of-concept studies. NACs generally have a standardized protocol and are less expensive compared to AECs. Nevertheless, NACs solely capture acute allergen exposure and have the further limitation of using allergen extracts rather than natural allergen. As the use of combined controlled methodologies is sparse, we recommend concurrent use of AECs and NACs to study short- and long-term effects of AR, thereby providing a more holistic representation of cat allergen-induced AR.

Structure-based prediction of the IgE epitopes of the major dog allergen Can f 1

Allergy to dogs has become increasingly prominent worldwide. Seven dog allergens have been identified, including Canis familiaris allergen 1-7 (Can f 1-7). Although Can f 1 is a major dog allergen sensitized to 50-75% of dog-allergic subjects, its IgE epitopes have not been identified. The structural analysis of an allergen is important to identify conformational epitopes. In this study, we generated a recombinant Can f 1 protein and determined its crystal structure using X-ray crystallography. Can f 1 had a typical lipocalin fold, which is composed of an eight-stranded β-barrel and α-helix, and has high similarity to Can f 2, Can f 4, and Can f 6 in overall structure. However, the localizations of surface charges on these proteins were quite different. Based on sequence alignment and tertiary structure, we predicted five critical residues (His86, Glu98, Arg111, Glu138, and Arg152) for the IgE epitopes. The relevance of these residues to IgE reactivity was assessed by generating Can f 1 mutants with these residues substituted for alanine. Although the effects of the mutation on IgE binding depended on the sera of dog-allergic patients, H86A and R152A mutants showed reduced IgE reactivity compared with wild-type Can f 1. These results suggest that Can f 1 residues His86 and Arg152 are candidates for the IgE conformational epitope.

Concordance of Skin Prick Test, Intradermal Testing, Serum IgE Levels and Symptoms in Patients with Allergic Rhinitis

Background: Diagnosis of allergic rhinitis is achieved by a combination of patient history and different screening tools, followed by specific provocation testing. Screening tools usually involve a skin prick test (SPT), specific serum IgE or a combination of both. Objective: The purpose of this study was to evaluate the correlation of SPT, intradermal testing and specific serum IgE testing in certain allergens and to evaluate sensitization rates, symptom patterns and time of symptoms in a cohort of patients with suspected allergic rhinitis. Methods: Data on 4653 patients with suspected allergic rhinitis were included and divided into five groups: spring bloomers (birch, hazel, etc.), summer bloomers (grasses and rye), autumn bloomers (ribwort and mugwort), mites and mold. Correlation of SPT, intradermal testing and specific IgE test results using Cohen’s kappa and logistic regression were carried out to evaluate the probability of symptoms. Results: Comparison of SPT and specific serum IgE led to kappa coefficients between 0.33 and 0.47, corresponding to a minor to moderate concordance. Comparing the symptoms reported by patients with sensitization diagnosed by SPT, a correlation was only found for spring and summer bloomers with an odds ratio of 1.5 and 2.1, respectively. The most prevalent symptom in the study cohort was rhinitis, followed by others such as asthma, sense of smell and atopic dermatitis. Conclusions: SPT seems to be more sensitive than specific IgE for detection of sensitization. Patients’ symptoms as well as the timing of symptoms, especially for perennial allergies, are not always very pronounced.

The Finnish Allergy Program 2008-2018: Society-wide proactive program for change of management to mitigate allergy burden

A 10-year national program to improve prevention and management of allergic diseases and asthma was implemented in Finland (population 5.5. million) in 2008-2018. The main aim was to reduce the long-term burden of these conditions. The strategy was changed from traditional avoidance to tolerance and resilience of the population. Health was endorsed instead of medicalization of mild symptoms. Disease severity was reevaluated, and disabling clinical manifestations were given high priority. For health care, 5 quantitative goals and 1 qualitative goal were set. For each of the goals, specific tasks, tools, and outcome evaluation were stipulated. During the program, 376 educational sessions gathered 24,000 health care participants. An information campaign targeted the lay public, and social media was used to contact people. In the 10 years of the program, the prevalence of allergic diseases and asthma leveled off. Asthma caused fewer symptoms and less disability, and 50% fewer hospital days. Food allergy diets in day care and schools decreased by half. Occupational allergies were reduced by 45%. In 2018, the direct and indirect costs of allergic diseases and asthma ranged from €1.5 billion to €1.8 billion, with the 2018 figures being 30% less than in the respective figures in 2007. The Finnish proactive and real-world intervention markedly reduced the public health burden of allergic disorders. The allergy paradigm was revisited to improve management with systematic education.

Assessment of health-related quality-of-life in patients with chronic Rhinosinusitis - Validation of the German Sino-Nasal Outcome Test-22 (German-SNOT-22)

PURPOSE

The Sino-Nasal-Outcome-Test-22 (SNOT-22) represents the reference questionnaire to assess symptoms, health-related quality-of-life (HRQOL) and treatment-response in patients with chronic rhinosinusitis (CRS). The SNOT-22 has been validated for various languages, yet no validation is available for the German version. Thus, we provide a validation of the SNOT-22 for German.

METHODS

In this prospective observational study 139 CRS-patients and 36 control-participants were included. CRS-patients completed the German-SNOT-22 before treatment (T0) and four (T1), twelve (T2) and 48 weeks after inclusion (T3). At T0, Mackay-Naclerio-, Lund-Mackay- and Brief-Symptom-Inventory-18 (BSI-18) scores were collected as external reference for the German-SNOT-22 and its subscales. At T1, T2, and T3 health-transition-items (HTIs) were raised to explore responsivity. Control-participants completed the German-SNOT-22 at T0. Reliability (internal consistency, item-total correlation), validity (concurrent validity, discriminatory validity) and responsiveness (distribution- and anchor-based) were explored for the German-SNOT-22.

RESULTS

At T0, the mean German-SNOT-22 total-score for CRS patients was 38.0 (± 20.9) and responded to treatment (T1 = 26.3 ± 19.1; T2 = 25.8 ± 20.6; T3 = 20.5 ± 16.3). For control-participants, the mean total-score at T0 was 15.1 (±10.9). The German-SNOT-22 was reliable (excellent internal consistency α = 0.93; good overall item-total correlations r = 0.39-0.85), valid (significant correlations between Mackay-Naclerio-, Lund-Mackay- and BSI-18 scores, all r > 0.39, p < 0.01) and responsive (significant correlations between HTIs and mean change in German-SNOT-22 total-score F = 9.57, p < 0.001).

CONCLUSION

The German-SNOT-22 validated here matches the original SNOT-22. It is a reliable, valid and responsive questionnaire to assess symptoms, HRQOL and treatment-response in CRS-patients. Good psychometric properties were observed.

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.

Value of Component Resolved Diagnostics to Aspergillus fumigatus in Patients with Upper Airway Complaints

INTRODUCTION

Sensitization to Aspergillus fumigatus is a risk factor for severe asthma. However, little is known about its presence, appearance, and impact on allergic rhinitis. Herein, we investigated the usefulness of component resolved diagnostics in patients sensitized to Aspergillus fumigatus protein extract.

METHODS

Seventy-eight patients with suspected allergic rhinitis and elevated IgE levels toward Aspergillus fumigatus protein extract were retrospectively evaluated regarding their total and Aspergillus-specific IgE levels and their skin prick test. Furthermore, they were tested for specific IgE antibodies against Asp f 1, 2, 3, 4, and 6.

RESULTS

Skin prick test missed 6 patients (7.7%) with elevated IgE toward Aspergillus fumigatus protein extract. Fifty percent of patients (n = 39) were sensitized to at least one component. Even though monosensitization affected all components, all patients with positivity toward more than one component were sensitized to Asp f 1. There was a statistically significant increase of Aspergillus-specific IgE with increasing number of components affected by sensitization. Many patients were oligo- (34.6%) or polysensitized (51.3%). There was a high prevalence of sinusitis (61.8%).

CONCLUSIONS

Component resolved diagnostic testing toward the major allergen Asp f 1 was less sensitive than skin prick test and serology to Aspergillus fumigatus protein extract. However, sensitivity of component resolved diagnostics might be underestimated. Diagnostics of the species-specific allergens Asp f 1, 2, and 4 might allow to differentiate between genuine and cross-reactive sensitization. In the clinical routine, skin prick test and serology to crude extract remain the methods of choice.

Minimizing the Number of Aeroallergen Extracts in Skin Prick Test in IgE-Mediated Allergic Disorders in Both Adults and Children in Jordan

Background

Skin prick test (SPT) is the most common diagnostic procedure that is performed considering the history of aeroallergen sensitivity among patients. Moreover, it is important to identify the diagnostic and therapeutic benefits of allergen’s number in skin prick testing in both adults and children.

Objective

The present study aims to detect the minimum number of allergens used in SPT to identify 95% of sensitized patients in both pediatric and adult age groups in Jordan.

Patients and Methods

Retrospective analysis of a 20 allergen extracts SPT results for 2253 patients (aged 8 and above) was conducted to assess the minimum number of allergen extracts needed to identify 95% of the sensitized patients in both adults and children.

Results

The results showed that 50.9% of the pediatric group was sensitized to at least one aeroallergen extract in comparison to 48.3% of the adult group. Only 8 allergen extracts were necessary to identify 95% of the sensitized patients which are olive pollen, Dermatophagoides pteronyssinus, Salsola kali, 4 cereals, Wall pellitory, Dermatophagoides farinae, Cypress and mugwort. Same number was needed in children but with the replacement of mugwort with alternaria to achieve a similar result.

Conclusion

The study concluded that only 8 allergen extracts were needed for detecting 95% of sensitized patients (both pediatrics and adults) in SPT. The authors proposed a two-stage screening: stage 1 includes the minimum number of allergen extracts to detect 95% of sensitized patients and stage 2 for the patients who tested negative in stage 1 which will include a broader allergen extracts panel excluding those which were already tested in stage 1.

Does the principle of homologous groups allow a reduction of allergens in the skin prick test panel?

PURPOSE

Regulatory and economic conditions drive the application of the concept of homologous groups on therapeutic and diagnostic formulations. In this context, a possible reduction of allergens in the skin prick test panel in the clinical routine should be investigated for the grass, birch and Dermatophagoides homologous group.

METHODS

Grass and cultivated rye skin prick test results of 1101 patients, birch/hazel/alder skin prick test results of 1131 patients and 1068 Dermatophagoides pteronyssinus and farinae skin prick tests were retrospectively evaluated with regard to sensitivity and false-negative rate detecting sensitization against cultivated rye with grass skin prick test, sensitization against hazel and/or alder with birch skin prick test and sensitization towards Dermatophagoides farinae with Dermatophagoides pteronyssinus skin prick test.

RESULTS

Skin prick test results in all groups highly correlated in Spearman Rank Order correlation. Sensitivity of grass skin prick test detecting sensitization against cultivated rye was highest with 98.9%, sensitivity of birch skin prick test detecting sensitization toward hazel and alder was 95.6 and 90.0%, respectively. Sensitivity of skin prick test with Dermatophagoides pteronyssinus detecting sensitization towards Dermatophagoides farinae was 93.6%. Only 26 patients with positive rye, hazel, alder or Dermatophagoides farinae skin prick test that were overlooked by grass, birch or Dermatophagoides pteronyssinus skin prick test reported allergic symptoms.

CONCLUSION

In routine clinical practice, sensitization against cultivated rye can safely be detected by skin prick test with grass allergen. In addition, the sensitivity of birch skin prick test is high in terms of sensitization towards hazel, but lower for alder. Sensitivity of Dermatophagoides pteronyssinus skin prick test also is high to detect sensitization towards Dermatophagoides farinae. Further research will indicate if several skin prick test allergens will disappear and be completely replaced by a single skin prick test based on the principle of homologous groups.

Molecular allergen sensitization of Aspergillus fumigatus between allergic bronchopulmonary aspergillosis and A fumigatus-sensitized asthma in Guangzhou, Southern China

Background

Few studies have assessed the sensitization of mycotic allergens and Aspergillus fumigatus molecular allergens. This study aimed to investigate the relationships of A fumigatus components and mycotic allergens in allergic bronchopulmonary aspergillosis (ABPA) patients and A fumigatus (Af)‐sensitized asthma patients.

Methods

Serum sIgE levels of Penicillium chrysogenum, Cladosporium herbarum, Mucor racemosus, Candida albicans, Alternaria alternata, Helminthosporium halodes, and A fumigatus allergen components (Asp f 1, Asp f 2, Asp f 3, Asp f 4, and Asp f 6) were measured via the ImmunoCAP assay in 18 ABPA and 54 Af‐sensitized asthma patients in Guangzhou city, China.

Results

94.44% of ABPA patients and 87.04% of Af‐sensitized asthma patients were co‐sensitized to at least one other fungal allergen. The positive rates of Asp f 1 (88.89% vs 59.26%, P < .05), Asp f 2 (66.67% vs 33.33%, P < .05), Asp f 4 (61.11% vs 33.33%, P < .05), and Asp f 6 (66.67% vs 14.81%, P < .001) in ABPA patients were higher than those in Af‐sensitized asthma patients. IgE levels of Asp f 1 (P < .05), Asp f 4 (P < .05), and Asp f 6 (P < .001) were higher in ABPA patients than in Af‐sensitized asthma patients. Optimal scale analysis showed that ABPA was more relevant to Af components (Cronbach's alpha = 90.7%).

Conclusion

The A fumigatus components and their relationships with various mycotic allergens were different in ABPA and Af‐sensitized asthma patients. This finding may help local doctors in the diagnosis and immunotherapy of fungal allergies.

Hypersensitivity to dipyrone in aspirin-exacerbated respiratory disease patients is associated with urticaria

OBJECTIVE

To phenotype patients with aspirin-exacerbated respiratory disease (AERD) according to the presence of atopy, urticaria and level of peripheral eosinophils.

METHODS

This study included adult asthmatic patients with AERD followed up at a tertiary hospital. They were classified according to atopy and/or urticaria, assessing clinical and laboratorial differences among the groups in order to identify possible aggravating factors of the disease.

RESULTS

We included 73 patients, 78.1% being female with a mean age of 54.0 years. Severe asthma was observed in 68.5% and respiratory exacerbation with dipyrone in 67.1% of these patients. They had median total serum IgE of 191.6 IU/mL, mean peripheral eosinophils of 718.5 cells/mm³, and 50.7% were atopic. Urticaria was observed in 32.9% of them, and exacerbations were more often triggered by dipyrone (p = .016). Atopic patients were younger than nonatopic patients (p = .023), and had, on average, higher total serum IgE levels (p = .022). We observed a good correlation between asthma severity and peripheral eosinophils count (r² = 026; p = .021).

CONCLUSIONS

In this study, severe asthma was highly prevalent in AERD patients. Likewise, urticaria was quite prevalent and its presence was associated with dipyrone induced hypersensitivity reaction. Atopy was found in half of the patients, with no association with asthma severity. Patients with higher levels of peripheral eosinophils had more severe asthma. Dypirone hypersensitivity may be a marker for concomitant respiratory and cutaneous hypersensitivity reactions.

Heterogeneity of Adult Rhinitis for Multimorbidity and Age at Onset among Non-Sensitized Rhinitis and Mono-/Poly-Sensitized Rhinitis: A Retrospective Cross-Sectional Study

BACKGROUND

Recent studies have proposed that clinical and immunological differences exist between mono- and poly-sensitized subjects with allergic diseases, and poly-sensitization was related to multimorbidity of allergic diseases among children and adolescents.

OBJECTIVE

We compared the clinical characteristics and multimorbidity of allergic diseases between adult rhinitis patients mono- and poly-sensitized to common aeroallergens using a retrospective cross-sectional study for tertiary care subjects.

METHODS

The medical records of 1,615 patients who were clinically diagnosed with rhinitis by an otolaryngologist and evaluated with skin prick tests were reviewed. The severity of the rhinitis symptoms, comorbidities (asthma, conjunctivitis, and eczema), family history of allergic diseases, and the results of skin prick tests were evaluated.

RESULTS

There were 392 patients with mono-sensitized rhinitis (mono-sR), 325 with poly-sensitized rhinitis (poly-sR), and 898 with non-sensitized rhinitis (non-sR). Comorbid conjunctivitis and eczema were most common in poly-sR, followed by mono-sR, and least common in non-sR patients. The age at onset of rhinitis was clearly different between adult patients with non-sR and mono-/poly-sR, but not between patients with mono-sR and poly-sR. However, the age at onset of rhinitis was much younger in non-sR and mono-sR patients with conjunctivitis or eczema than those without such comorbidities.

CONCLUSION

Thefrequency of comorbid conjunctivitis and eczema in adult rhinitis patients differed by a quantitative trait of immunoglobulin E sensitization. Depending on the multimorbidity of allergic diseases, onset age of rhinitis seems to be different in adult rhinitis patients.

Defining challenge-proven coexistent nut and sesame seed allergy: A prospective multicenter European study

BACKGROUND

Peanut, tree nut, and sesame allergies are responsible for most life-threatening food-induced allergic reactions. Rates of coexistent allergy between these foods have been from mostly retrospective studies that include only a limited number of tree nuts or were not based on oral food challenges.

OBJECTIVE

The Pronuts study is a multicenter European study (London, Geneva, and Valencia) assessing the challenge-proven rate of coexistent peanut, tree nut, and/or sesame seed allergy.

METHODS

Children aged 0 to 16 years with at least 1 confirmed nut or sesame seed allergy underwent sequential diagnostic food challenges to all other nuts and sesame seed.

RESULTS

Overall, the rate of coexistent peanut, tree nut, and sesame seed allergy was 60.7% (n = 74/122; 95% CI, 51.4% to 69.4%). Peanut allergy was more common in London, cashew and pistachio nut allergies were more common in Geneva, and walnut and pecan allergies were more common in Valencia. Strong correlations were found between cashew-pistachio, walnut-pecan, and walnut-pecan-hazelnut-macadamia clusters. Age (>36 months) and center (Valencia > Geneva > London) were associated with an increased odds of multiple nut allergies. By pursuing the diagnostic protocol to demonstrate tolerance to other nuts, participants were able to introduce a median of 9 nuts.

CONCLUSION

We found a higher rate of coexistent nut and sesame seed allergies than previously reported. Performing sequential food challenges was labor intensive and could result in severe allergic reactions; however, it reduced dietary restrictions. Age was a significant predictor of multiple nut allergies, and thus the secondary spread of nut allergies occurred in older children.

Allergic Rhinitis to Weed Pollen in Germany: Dominance by Plantain, Rising Prevalence, and Polysensitization Rates over 20 Years

BACKGROUND

In contrast to the 3 major aeroallergens tree pollen, grass pollen, and house dust mites, allergic rhinitis caused by herbal pollen has received comparatively little attention in recent clinical studies. Since various weeds flower during summer until fall, allergic rhinitis to weeds may be underdiagnosed and/or mistakenly diagnosed as grass pollen allergy.

OBJECTIVE

To investigate (i) the currently most frequent weed allergy between mugwort, ragweed, plantain, chamomile, nettle, and oilseed rape and (ii) time trends in prevalence of sensitization to weed pollen in the middle of Germany over the last 20 years.

METHODS

This study, the largest of its kind to date, monocentrically evaluated the prick test results of a total of 6,220 patients with suspected RCA over a period of 20 years (1998-2017).

RESULTS

In the study cohort, sensitization rates to plantain almost doubled from 26.6% in the decade 1998-2007 to 50.5% in 2008-2017. Identical increases were observed for ragweed, while sensitization rates for mugwort stayed largely unchanged. The most prominent increase in positive skin prick tests to plantain and ragweed pollen was mainly observed in younger patients. Further, we identified a trend toward polysensitization, currently dominated by plantain and ragweed. Sensitization to weed pollen was found to be highly associated with additional sensitizations to grass and/or birch pollen.

CONCLUSION

Plantain is currently the best choice to screen rhinitis patients for weed allergy which identifies 86% of all weed-sensitized individuals, at least in Germany. Over the last 20 years, we demonstrate a significant rise in the total number of weed pollen sensitization as well as increases in polysensitization, predominantly in younger patients.

Dramatically decreased T cell responses but persistent IgE upon reduced pollen exposure

Mugwort pollen allergy is frequent in parts of Europe. As mugwort pollen contains only one major allergen, Art v 1, which harbors only one T cell epitope, we employed mugwort pollen allergy as a model to study allergen-specific T cell responses. However, after 2004, we noticed a drastic decrease in the T cell responses to Art v 1 and eventually it became almost impossible to detect allergen-specific responses at the T cell level in mugwort-allergic individuals. To explain this observation, we retrospectively investigated the local exposure to mugwort pollen and its possible correlation to the frequency and reactivity of allergen-specific T cells. The total annual pollen indices dramatically dropped after 2004 and never reached previous levels again. Local sensitization to mugwort pollen and serum IgE antibodies specific for Art v 1 remained unchanged until 2015. Our mugwort pollen model shows that specific IgE-levels are maintained for extremely long time periods in spite of a long-term reduction of natural allergen exposure to levels that are too low to boost specific T cells.

Western oropharyngeal and gut microbial profiles are associated with allergic conditions in Chinese immigrant children

BACKGROUND

The allergy epidemic resulting from western environment/lifestyles is potentially due to modifications of the human microbiome. Therefore, it is of interest to study immigrants living in a western environment as well as their counterparts in the country of origin to understand differences in their microbiomes and health status.

METHODS

We investigated 58 Australian Chinese (AC) children from Perth, Western Australia as well as 63 Chinese-born Chinese (CC) children from a city in China. Oropharyngeal (OP) and fecal samples were collected. To assess the microbiomes, 16s ribosomal RNA (rRNA) sequencing for variable regions V3 and V4 was used. Skin prick tests (SPT) were performed to measure the children's atopic status. Information on food allergy and wheezing were acquired from a questionnaire.

RESULTS

AC children had more allergic conditions than CC children. The alpha diversity (mean species diversity) of both OP and gut microbiome was lower in AC children compared to CC children for richness estimate (Chao1), while diversity evenness (Shannon index) was higher. The beta diversity (community similarity) displayed a distinct separation of the OP and gut microbiota between AC and CC children. An apparent difference in microbial abundance was observed for many bacteria. In AC children, we sought to establish consistent trends in bacterial relative abundance that are either higher or lower in AC versus CC children and higher or lower in children with allergy versus those without allergy. The majority of OP taxa showed a consistent trend while the majority of fecal taxa showed a contrasting trend.

CONCLUSION

Distinct differences in microbiome compositions were found in both oropharyngeal and fecal samples of AC and CC children. The association of the OP microbiome with allergic condition is different from that of the gut microbiome in AC children. The microbiome profiles are changed by the western environment/lifestyle and are associated with allergies in Chinese immigrant children in Australia.

Treatment Outcomes in Chronic Rhinosinusitis Refractory to Maximal Medical Therapy: A Prospective Observational Study Under Real-World Conditions

This investigation explored the outcomes of 4 standardized treatments in patients with refractory chronic rhinosinusitis (CRS), despite recent maximal medical therapy (MMT). In a prospective observational study, we compared continued nasal steroids and irrigation (cNSI), repeated MMT (rMMT), pulsed nasal steroid inhalation (PSI), and endoscopic sinus surgery (ESS). Between November 2015 and March 2016, patients with symptomatic CRS despite having received MMT during the year prior to symptom reoccurrence were offered 1 of 4 standardized treatments. Reflecting real-world conditions, patients selected their treatment option following physician counseling. Sino-Nasal Outcome Test-22 (SNOT-22) scores were obtained before treatment, at the end of treatment, and at 2 months and 1 year following treatment. The mean (± standard deviation [SD]) duration since last MMT was 144 (±36 days). Of the 130 patients, 52 selected cNSI, 16 PSI, 19 rMMT, and 43 ESS. Mean SNOT-22 scores before treatment did not significantly differ between treatments (P = .99). Overall, SNOT-22 scores decreased from 38 ± 2 before treatment to 20 ± 2 after 1 year (P < .001), with a higher reduction for patients having CRS with nasal polyps than for those without nasal polyps (35 ± 2 to 15 ± 2 vs 41 ± 3 to 25 ± 4, respectively; both P < .001). Overall, no difference between the 3 medical treatments was observed (all P > .2). Post-treatment scores following ESS (19 ± 2) were significantly lower than for each of the 3 medical treatments (cNSI 26 ± 2, P = .004; PSI 27 ± 3, P = .026; rMMT 28 ± 3, P = .008). At 1 year following ESS, 26 of 31 patients were asymptomatic and did not require additional systemic steroids, compared to 25 of 50 patients following medical treatment (P = .002). The investigated standardized treatments significantly improved SNOT-22 scores in patients with refractory CRS under real-world conditions. Both patients having CRS with and those without nasal polyps showed significant improvement in SNOT-22 scores, although a less profound effect was found among the latter group. Patients who selected ESS were less symptomatic during the first follow-up year than patients who selected medical treatment alone. Patients with refractory CRS did not benefit from an additional course of MMT in comparison to those who were treated only with cNSI.

DNA methylation and allergic sensitizations: A genome-scale longitudinal study during adolescence

BACKGROUND

The presence of allergic sensitization has a major influence on the development and course of common childhood conditions such as asthma and rhinitis. The etiology of allergic sensitization is poorly understood, and its underlying biological mechanisms are not well established. Several studies showed that DNA methylation (DNAm) at some CpGs is associated with allergic sensitization. However, no studies have focused on the critical adolescence period.

METHODS

We assessed the association of pre- and postadolescence genome-wide DNAm with allergic sensitization against indoor, outdoor and food allergens, using linear mixed models. We hypothesized that DNAm is associated with sensitization in general, and with poly-sensitization status, and these associations are age- and gender-specific. We tested these hypotheses in the IoW cohort (n = 376) and examined the findings in the BAMSE cohort (n = 267).

RESULTS

Via linear mixed models, we identified 35 CpGs in IoW associated with allergic sensitization (at false discovery rate of 0.05), of which 33 were available in BAMSE and replicated with respect to the direction of associations with allergic sensitization. At the 35 CpGs except for cg19210306 on C13orf27, a reduction in methylation among atopic subjects was observed, most notably for cg21220721 and cg11699125 (ACOT7). DNAm at cg10159529 was strongly correlated with expression of IL5RA in peripheral blood (P-value = 6.76 × 10^-20 ). Three CpGs (cg14121142, cg23842695, and cg26496795) were identified in IoW with age-specific association between DNAm and allergic sensitization.

CONCLUSION

In adolescence, the status of allergic sensitization was associated with DNAm differentiation and at some CpGs the association is likely to be age-specific.

Association of molds and metrological parameters to frequency of severe asthma exacerbation

Background

Sensitization to airborne molds may be a risk factor for severe asthma and direct cause of asthma exacerbation (AE).

Methods

A prospective, 1-year (April 2016-March 2017) study, done in Kuwait Allergy Centre, investigated the link between AEs with exposure to outdoor molds and the role of meteorological parameters in mold sensitized patients and compared with non-allergic asthma patients who had asthma deterioration. The total of 676 adult asthmatics with moderate-severe AEs were included and divided into atopic (85.65%) and non-atopic group. Atopy was defined by positive skin prick test (SPT) to at least one inhalant allergen. Data regarding atopy and asthma severity were collected from patient's records. Patients with symptoms and signs of acute respiratory infection and patient sensitized to indoor allergens only were excluded. Daily count of local pollens (Salsola kali, Bermuda grass) and molds (Aspergillus, Alternaria and Cladosporium) were obtained from the Aerobiology department. Daily metrological parameters (atmospheric pressure-AP, temperature-T and relative humidity-RH) were provided by Kuwait Environment Public Authority. Count of spores/m³ and weather variable are shown on weekly basis. The year circle was divided into 4 Seasons (1, 2, 3, 4) accordingly to typical desert climate.

Results

Sensitization to molds was relatively high but significantly less (25.0%) if compared to the pollens sensitization. The highest number of AEs was in season 4 for both molds and pollens sensitized patients. Seasonal patterns for both allergens were significant and positively correlated with RH and AP. In season 1 only, mold sensitized patients showed higher rate of AEs. Non-atopic patients have been less sensitive to increased RH than atopic. Negative correlation with T was similar in both atopic and non-atopic patients.

Conclusion

Despite of high rate of sensitization to molds, their significant role in triggering AE was not found in desert environment. Typical desert climate and high allergencity of local weeds outweigh the influence of the molds.

Disentangling the heterogeneity of allergic respiratory diseases by latent class analysis reveals novel phenotypes

BACKGROUND

Refined phenotyping of allergic diseases may unravel novel phenotypes. Conjunctivitis as an independent disorder has never been approached.

AIM

To identify distinct classes of allergic respiratory diseases using latent class analysis (LCA) and distinguish each class using classification and regression tree (CART) analysis.

METHODS

Seven hundred and twenty-eight adults from the Portuguese general population study ICAR had a structured medical interview combined with blood collection, skin prick tests, spirometry with bronchodilation, and exhaled nitric oxide. LCA was applied to 19 variables. The CART algorithm selected the most likely variables distinguishing LCA-classes.

RESULTS

A six-class model was obtained. Class 1 (25%): nonallergic participants without bronchial or ocular symptoms. Classes 2 (22%) and 3 (11%): nasal and ocular (low levels) symptoms without nasal impairment, monosensitized (Class 2) or polysensitized (Class 3). Class 4 (13%): polysensitized participants with high levels of nasal and ocular symptoms, and nasal impairment. Classes 5 (16%) and 6 (14%): high level of nasal, bronchial and ocular symptoms with nasal impairment (non-allergic or polysensitized, respectively). Participants in classes 5 and 6 had more bronchial exacerbations and unscheduled medical visits (P < 0.001). Ocular symptoms were significantly higher in classes with nasal impairment, compared to those without impairment (P < 0.001) or no nasal symptom (P < 0.001). CART highlighted ocular symptoms as the most relevant variable in distinguishing LCA-classes.

CONCLUSION

Novel severe phenotypes of participants with co-occurrence of ocular, nasal and bronchial symptoms, and exacerbation-prone were identified. The tree algorithm showed the importance of the ocular symptoms in the expression of allergic diseases phenotypes.

Clinical and immunological differences between asymptomatic HDM-sensitized and HDM-allergic rhinitis patients

BACKGROUND

Confirmation of the clinical relevance of sensitisation is important for the diagnosis of allergic rhinitis.

OBJECTIVE

To investigate the usefulness of an in vitro basophil activation test and component-resolved diagnosis in distinguishing between symptomatic allergic rhinitis patients and asymptomatic sensitization to house dust mites (HDMs).

METHODS

Thirty-six subjects with a positive skin prick test (SPT) for HDM were divided into a symptomatic (n = 17) and an asymptomatic (n = 19) group on the basis of their clinical history and a nasal provocation test. A basophil CD63 response to in vitro stimulation with Dermatophagoides pteronyssinus whole allergen extract and the IgE reactivity profiles for Der p 1, 2, 4, 5, 7, 10, 11, 14, 15, 18, 21, 23 were evaluated. Serum IgE and IgG specific to D pteronyssinus whole allergen extract and total IgE were measured.

RESULTS

There were no statistically significant differences in the levels of IgE (IgE levels were higher in symptomatic patients with P = 0.055) and IgG specific to D pteronyssinus and total IgE. Symptomatic patients showed a lower threshold for in vitro basophil activation (3.33 ng/mL vs 33.3 ng/mL), a higher area under the curve (AUC) of basophil activation (171 vs 127) (P = 0.017), a higher response to positive control with anti-FcεRI stimulation (97% vs 79%) (P < 0.001), a recognition of more HDM allergens (4 vs 2) and more frequent sensitization to rDer p 7 (P = 0.016) and rDer p 23 compared to asymptomatic subjects (P = 0.018). There was a positive correlation (r = 0.63; P < 0.001) between the number of recognized allergens and the AUC of basophil activation.

CONCLUSION AND CLINICAL RELEVANCE

In the subjects studied, the differences in the basophil response to D pteronyssinus allergen extract, number of recognized HDM allergens and reactivity to rDer p 7 and rDer p 23 distinguish symptomatic from asymptomatic HDM sensitisation better than SPT or allergen extract-specific IgE. Information regarding the clinical relevance of sensitization is important for the prescription of allergen-specific immunotherapy.

The SNOT-22 factorial structure in European patients with chronic rhinosinusitis: new clinical insights

PURPOSE

The sino-nasal outcomes test-22 (SNOT-22) represents the reference questionnaire to assess patients with chronic rhinosinusitis (CRS). As weak correlations between objective CRS parameters and SNOT-22 total score have been observed, factor analyses have aimed to identify underlying factorial structures. However, ambiguous factor loadings and problematic item-domain assignments have resulted. Moreover, such factor analyses have mainly been performed in non-European CRS patients, while European data remain sparse. This study thus sought to address these issues.

METHODS

Principal component analysis and confirmatory factor analysis were performed from SNOT-22 questionnaires completed by European CRS patients. Goodness of fit, internal consistencies, and factor loadings were calculated. Item-domain assignment was based on statistical grounds and clinical meaningfulness. Additionally, this study investigated correlations between SNOT-22 domains and external reference criteria, including Lund-Mackay score, Lund-Naclerio score and the brief symptom inventory 18 (BSI-18).

RESULTS

One hundred and thirty-four European CRS patients were included. Principal component analysis proposed four SNOT-22 domains ("nasal symptoms", "otologic symptoms", "sleep symptoms", "emotional symptoms"), which explained 63.6% of variance. Observed item-domain-assignment differed from previously proposed item-domain assignments. All factor loadings were > 0.5, except "cough" (0.42) and "facial pain or pressure" (0.49). For confirmatory factor analysis, satisfactory goodness of fit (RMSEA = 0.66; CFI = 0.92; TLI = 0.90) and internal consistencies (Cronbach-α: total score = 0.93; domains = 0.75-0.91) were observed. Significant positive correlations were found between the "nasal symptoms" domain and both the Lund-Mackay score (r = 0.48; p < 0.001) and the Lund-Naclerio score (r = 0.27, p < 0.01). Significant positive correlations were also identified between "emotional symptoms" and BSI-18 total score (r = 0.64, p < 0.001).

CONCLUSIONS

Principal component analysis performed for SNOT-22 questionnaires completed by European CRS patients indicated a different item-domain-assignment than previously reported. Confirmatory factor analysis suggested acceptable and clinically plausible psychometric properties for the resulting factorial structure. Significant correlations between the "nasal symptoms" and the "emotional symptoms" domains were observed with objective CRS parameters. The resulting factorial structure with different item-domain assignments may thus be more suitable for European CRS patients.

Crystal structure of the dog allergen Can f 6 and structure-based implications of its cross-reactivity with the cat allergen Fel d 4

Several dog allergens cause allergic reactions in humans worldwide. Seven distinct dog allergens, designated Canis familiaris allergen 1 to 7 (Can f 1-Can f 7), have been identified thus far. Can f 6 shows high sequence similarity and cross-reactivity with Fel d 4 and Equ c 1, major cat and horse allergens, respectively. This study was conducted on the allergenic epitopes of Can f 6 based on its structural characterization. We demonstrated that sera from 18 out of 38 (47%) dog-sensitized patients reacted to recombinant Can f 6 protein (rCan f 6). We then determined the crystal structure of rCan f 6 by X-ray crystallography, which exhibited a conserved tertiary structural architecture found in lipocalin family proteins. Based on the tertiary structure and sequence similarities with Fel d 4 and Equ c 1, we predicted three IgE-recognizing sites that are possibly involved in cross-reactivity. Substituting three successive amino acids in these sites to triple alanine decreased IgE reactivity to the allergen. However, the degree of reduction in IgE reactivity largely depended on the site mutated and the serum used, suggesting that Can f 6 is a polyvalent allergen containing multiple epitopes and Can f 6-reactive sera contain varied amounts of IgE recognising individual Can f 6 epitopes including those predicted in this study. We also demonstrated that the predicted epitopes are partly involved in IgE cross-reactivity to Fel d 4. Interestingly, the effect of the mutation depended on whether the protein was structured or denatured, indicating that the bona fide tertiary structure of Can f 6 is essential in determining its IgE epitopes.

Crystal structure of the dog allergen Can f 6 and structure-based implications of its cross-reactivity with the cat allergen Fel d 4

Several dog allergens cause allergic reactions in humans worldwide. Seven distinct dog allergens, designated Canis familiaris allergen 1 to 7 (Can f 1-Can f 7), have been identified thus far. Can f 6 shows high sequence similarity and cross-reactivity with Fel d 4 and Equ c 1, major cat and horse allergens, respectively. This study was conducted on the allergenic epitopes of Can f 6 based on its structural characterization. We demonstrated that sera from 18 out of 38 (47%) dog-sensitized patients reacted to recombinant Can f 6 protein (rCan f 6). We then determined the crystal structure of rCan f 6 by X-ray crystallography, which exhibited a conserved tertiary structural architecture found in lipocalin family proteins. Based on the tertiary structure and sequence similarities with Fel d 4 and Equ c 1, we predicted three IgE-recognizing sites that are possibly involved in cross-reactivity. Substituting three successive amino acids in these sites to triple alanine decreased IgE reactivity to the allergen. However, the degree of reduction in IgE reactivity largely depended on the site mutated and the serum used, suggesting that Can f 6 is a polyvalent allergen containing multiple epitopes and Can f 6-reactive sera contain varied amounts of IgE recognising individual Can f 6 epitopes including those predicted in this study. We also demonstrated that the predicted epitopes are partly involved in IgE cross-reactivity to Fel d 4. Interestingly, the effect of the mutation depended on whether the protein was structured or denatured, indicating that the bona fide tertiary structure of Can f 6 is essential in determining its IgE epitopes.

Pre-participation health evaluation in adolescent athletes competing at Youth Olympic Games: proposal for a tailored protocol

Objective

To promote sports participation in young people, the International Olympic Committee (IOC) introduced the Youth Olympic Games (YOG) in 2007. In 2009, the IOC Consensus Statement was published, which highlighted the value of periodic health evaluation in elite athletes. The objective of this study was to assess the efficacy of a comprehensive protocol for illness and injury detection, tailored for adolescent athletes participating in Summer or Winter YOG.

Methods

Between 2010 and 2014, a total of 247 unique adolescent elite Italian athletes (53% females), mean age 16±1,0 years, competing in 22 summer or 15 winter sport disciplines, were evaluated through a tailored pre-participation health evaluation protocol, at the Sports Medicine and Science Institute of the Italian Olympic Committee.

Results

In 30 of the 247 athletes (12%), the pre-participation evaluation led to the final diagnosis of pathological conditions warranting treatment and/or surveillance, including cardiovascular in 11 (4.5%), pulmonary in 11 (4.5%), endocrine in five (2.0%), infectious, neurological and psychiatric disorders in one each (0.4%). Based on National and International Guidelines and Recommendations, none of the athletes was considered at high risk for acute events and all were judged eligible to compete at the YOG. Athletes with abnormal conditions were required to undergo a periodic follow-up.

Conclusions

The Youth Pre-Participation Health Evaluation proved to be effective in identifying a wide range of disorders, allowing prompt treatment, appropriate surveillance and avoidance of potential long-term consequences, in a significant proportion (12%) of adolescent Italian Olympic athletes.

Component resolved analysis of ash pollen allergy in Bavaria

Background

Sensitization to ash pollen is underestimated in various regions. The prevalence in Germany is about 10%. However, allergy to ash pollen is widely overlooked by allergists, since the pollination period of ash and birch in central Europe closely overlap and rhinoconjunctival symptoms during April/May are often assigned to birch pollen. Component resolved analysis of the different ash allergens is not routinely available. Therefore, we would like to question the usefulness of component resolved diagnostic via olive components, as ash and olive are both part of the Oleaceae family.

Methods

113 patients with nasal provocation and skin prick test to ash were retrospectively compared regarding their specific immunoglobulin E antibody profiles with response to native ash extract, rOle e 1, nOle e 7 and rOle e 9.

Results

In nasal provocation testing 58% of 113 patients sensitized to ash were allergic, 42% were only sensitized without showing symptoms. Skin prick testing and serology against native ash extract detected most patients sensitized to ash pollen, whereas rOle e 1 was less sensitive. However, the value of measurements of skin prick test, serology to native ash extract and rOle e 1 did not allow a differentiation between an allergy and clinically silent sensitization. Specific antibodies to nOle e 7 and rOle e 9 were only seen in individual patients and were all positive for native ash extract and rOle e 1.

Conclusion

Skin prick testing and serology to native extract of ash pollen are the most reliable tools to diagnose a sensitization to ash pollen for patients living in Germany. Component resolved diagnostic to the major allergen rOle e 1 as representative of the Oleaceae family is possible but was less sensitive. Diagnostic of nOle e 7 and rOle e 9 did not show any additional benefit. Regarding differentiation between allergy and clinically silent sensitization to ash pollen, provocation is the leading diagnostic tool. Concluding, in routine clinical practice the standard methods-skin prick test, serology to native ash extract and provocation testing-remain crucial in the diagnosis and differentiation of ash sensitization and allergy.

The relevance of house dust mites allergy in clinical practice: the epidemiological impact on allergen immunotherapy

House dust mite (HDM) is the most common cause of respiratory allergy worldwide. The impact of HDM allergy is influenced by a number of factors, including local climate. We investigated such issue in Italy, using a real-life setting, including outpatients visited at allergy clinics. In 9143 patients (7873 adults and 1270 children) who were evaluated in 15 allergy clinics, investigating as well the rate of prescription of allergen immunotherapy. The present study confirms that Mediterranean climate is associated with a higher prevalence of mite allergy than continental climate. This significant difference may have an impact on allergen immunotherapy prescription, which should be more common in areas with higher prevalence of HDM allergy.

Combining MucilAir™ and Vitrocell® Powder Chamber for the In Vitro Evaluation of Nasal Ointments in the Context of Aerosolized Pollen

Hay fever is notoriously triggered when nasal mucosa is exposed to allergenic pollen. One possibility to overcome this pollen exposure may be the application of an ointment with physical protective effects. In this context, we have investigated Bepanthen^® Eye and Nose Ointment and the ointment basis petrolatum as reference while using contemporary in vitro techniques. Pollen from false ragweed (Iva xanthiifolia) was used as an allergy-causing model deposited as aerosol using the Vitrocell^® Powder Chamber (VPC) on Transwell^® inserts, while being coated with either Bepanthen^® Eye and Nose Ointment and petrolatum. No pollen penetration into ointments was observed upon confocal scanning laser microscopy during an incubation period of 2 h at 37 °C. The cellular response was further investigated by integrating the MucilAir™ cell system in the VPC and by applying pollen to Bepanthen^® Eye and Nose Ointment covered cell cultures. For comparison, MucilAir™ were stimulated by lipopolysaccharides (LPS). No increased cytokine release of IL-6, TNF-α, or IL-8 was found after 4 h of pollen exposure, which demonstrates the safety of such ointments. Since nasal ointments act as a physical barrier against pollen, such preparations might support the prevention and management of hay fever.

Quality of life is significantly impaired in nonallergic rhinitis patients

BACKGROUND

In contrast to the well-known significant impairment of quality of life (QoL) in allergic rhinitis (AR), the degree of impairment in QoL in nonallergic rhinitis (NAR) remained unknown for a long time, due to a lack of a validated questionnaire to assess QoL in the NAR patient group. In this study, a validation of the mini-RQLQ questionnaire in NAR patients was performed, followed by an assessment of QoL in NAR patients compared to AR and healthy controls. Secondly, use of medication and treatment satisfaction in AR and NAR was assessed.

METHODS

The study was an observational cohort study in 287 AR and 160 NAR patients. Patients with symptoms of rhinitis were recruited from a tertiary care outpatient clinic of the Otorhinolaryngology Department. Allergic rhinitis (AR) was defined as one or more positive results on skin prick testing and clinically relevant symptoms of rhinitis related to their sensitization. Nonallergic rhinitis (NAR) was defined as clinically relevant symptoms of rhinitis but without positive results on skin prick testing. The mini-RQLQ was successfully validated in this study for NAR patients.

RESULTS

Quality of life (QoL) in NAR patients was equally-and for some aspects even more-impaired compared to AR. More than half of both AR and NAR patients were unsatisfied with treatment.

CONCLUSION

These results demonstrate a significant impairment in both AR and NAR patients in their QoL combined with a low treatment satisfaction, emphasizing the need for adequate treatment, especially in the NAR patient group.