It's not just the indoor allergen that influences asthma

Il est connu depuis longtemps que l’environnement influence l’asthme par effets des allergènes, des irritants et de la pollution atmosphérique sur l’arbre bronchique. De nouveaux facteurs sont de plus en plus décrits dans l’apparition ou l’aggravation de l’asthme mais peu rechercher en pratique. L’environnement interne domestique ou professionnel, dont lequel nous passons plus de temps peut contribuer à l’apparition ou l’aggravation d’un asthme. Cet environnement est complexe. Il est composé d’allergènes, de produits chimiques, de gaz, d’animaux et de produits électriques. Ces facteurs peuvent majorer l’inflammation bronchique et entrainant ainsi un non contrôle de l’asthme. Par ailleurs, en raison du changement du mode de vie, on est moins exposé au soleil ; Ce qui favorise le déficit en vitamine D, qui va majorer l’inflammation bronchique et le risque d’infections respiratoires. La conséquence sera l’augmentation de la fréquence des exacerbations et du non contrôle de l’asthme. Tout récemment, les chercheurs ont démontré l’implication de tous ces facteurs environnementaux dans la perturbation du microbiome respiratoire nécessaire dans la régulation de l’inflammation bronchique. Mots clés : asthme, environnement interne, produits chimiques, vitamine D, microbiome.

Reliability and Correlation Between Indoor Allergen Concentrations from Vacuumed Surface Samples and Electrostatic Dust Collectors

Objectives Most studies on indoor allergen exposure used vacuumed surface samples for quantification. One alternative is electrostatic dust collectors (EDCs), which sample previously airborne settled dust. The aim of this study was to compare allergen quantification using two different sampling methods, with respect to repeatability, and to determine how well the results agree with one another. Methods Four times a year, measurements were made from samples that were either collected from the vacuuming of surfaces, or from EDCs, from 20 German day-care centers totaling 167 rooms. Overall, 504 vacuumed samples collected from smooth floors, 435 samples from carpets, 291 samples from upholstered furniture and beds, and 605 EDC samples were analyzed using six fluorescence enzyme immunoassays recognizing Fel d 1, Can f 1, Mus m 1, domestic mite (DM), Dermatophagoides pteronyssinus (Dp), and Tyrophagus putrescentiae (Tp) antigens. Variances and correlations among the repeat measurements over the course of the year within each sample type, and the correlations between surface samples and the corresponding EDC samples were calculated. Results Repeat measurements over the year correlated significantly with one another. However, only Fel d 1, Can f 1, and DM in the EDC samples; DM, Dp, Tp, and Fel d 1 in the upholstered furniture samples; and DM in the carpet samples show representative results of single measurements according to their variance ratios (within-room/between-room variance <1). The highest correlation between surface and EDC samples was found for Fel d 1 on the upholstered furniture (r 0.52), followed by Can f 1 on the upholstered furniture and Can f 1 on carpets (r 0.47 and 0.45, respectively). The maximum correlation for mite antigens was between carpet samples and EDC (DM r 0.27, Dp r 0.33). Mus m 1 and Tp antigens for the most part did not correlate to the EDC results. Conclusions Both vacuumed dust from upholstered furniture and EDC samples were suitable for repeatable quantification of several allergens in day-care centers within a year. However, there was little agreement among the different collection methods, especially for Mus m 1 and certain mite antigens. Therefore, the method and location used for collection may greatly influence allergen exposure assessment and study results.