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Copyright of Revue Francaise d'Allergologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue Francaise d'Allergologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue Francaise d'Allergologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue Francaise d'Allergologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Peanut allergy diagnosis relies on various tests including the oral food challenge (OFC), which is potentially associated with severe symptoms such as anaphylaxis. An alternative has emerged, the basophil activation test (BAT), which allows to determine the basophil allergen threshold sensitivity in vitro. We aimed to determine the discriminative ability of BAT between, first, OFC reactive and non-reactive patient, and secondly low or high cumulative dose-reactive patients in comparison with other diagnostic tools for peanut allergy. The ability of BAT to discriminate patient with mild or severe OFC clinical reactions was also evaluated. We performed a prospective study, from February 2018 to October 2020, evaluating in 79 peanut allergic children the basophils allergen reactivity (CDmax) and the basophils allergen sensitivity [CDsens or area under the curve (AUC)] in BAT (CD63+ or CD203c+) as well as specific IgE level and skin prick-test in relation to OFC performed the same day. Based on ROC curve analyses, optimal cutoff of CDmax, CDsens and AUC to peanut and Ara h 2 were defined by the Youden index. Among the 79 children included, ROC curve analysis showed that f13- or Ara h 2-CDmax and AUC appeared to be the best markers associated with reactivity on OFC. We defined positive cutoff [i.e. Closet to 100% positive predictive value (PPV)] and demonstrated that 21% of the OFC could have been avoided. Also, by discriminating peanut-reactive patients according to low (< 200 mg) or high (> 200 mg) cumulative dose of peanut proteins in OFC [corresponding to effective dose 50 (ED50)], basophils allergen sensitivity monitored with AUC to f13 and Ara h 2 were the best biomarkers predicting cumulative dose with 92% and 88% specificity and 88% and 91% sensitivity, respectively. BAT to f13 and Ara h 2 may be a useful diagnostic tool to predict the allergic status and could reduce dangerous OFC. Then, BAT may be useful for risk assessment of clinical reactions during OFC and could significantly improve management by integrating a personalized approach. [ABSTRACT FROM AUTHOR]

Copyright of Societes is the property of De Boeck Universite and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue Francaise d'Allergologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: In order to control their release, drugs are encapsulated into systems which are expected to provide a certain site with a predetermined amount of drug over a well-defined period of time. Here we report on a multi-component drug delivery biomaterial that consists of a hydrogel matrix in which drug-loaded biodegradable microcarriers are dispersed, and whose potential applications could be found in the design of implantable devices with long-term activity, as required by contraceptive and hormone replacement treatments. The release profile of the drug can actually be tuned by the complex interplay of several release mechanisms, including the permeability and eventually the degradation rate of the microcarriers and the diffusion through the hydrogel. The hydrogel consisted of 2-hydroxyethyl methacrylate cross-linked by ethylene glycol dimethacrylate. The microcarriers were biodegradable poly-ε-caprolactone (PCL) microspheres in which active molecules, such as levonorgestrel (LNG), were encapsulated. The hydrogels were characterized by water swelling, thermal properties, LNG diffusion through drug-free and drug-depleted hydrogel membranes and LNG release from devices with drug dispersed in the hydrogel. The PCL microspheres were observed by scanning electron microscopy; their size distribution, LNG loading and release were also investigated. The hydrogel-microsphere assemblies were characterized in terms of the distribution of the microspheres within the hydrogel, water swelling and the release of the encapsulated molecules. The developed device, due to its composite structure, has the ability to combine several release mechanisms, leading to drug release obeying zero-order kinetics for most of the time. [Copyright &y& Elsevier]

Copyright of Revue Francaise d'Allergologie is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Résumé Les allergies aux médicaments concernent environ 7 % de la population et pourtant les mécanismes physiopathologiques sont encore mal connus. Ici sont résumés les principaux mécanismes de présentation de l’antigène au système immunitaire adaptatif. Drugs allergies affect more than 7 % of the population and yet the pathophysiological mechanisms are still poorly known. Herein, we summarize the main mechanisms of antigen presentation to the adaptive immune system. [ABSTRACT FROM AUTHOR]

Introduction La détection et la quantification des immunoglobulines (Ig) E spécifiques d’allergène est une étape importante du diagnostic et du suivi en allergologie. Elle est soumise actuellement, au même titre que l’ensemble des examens de biologie médicale, à l’obligation d’accréditation selon la norme internationale EN ISO 15189. Le réseau des biologistes de l’allergie AllergoBioNet propose une procédure d’accréditation du dosage des IgE spécifiques d’allergène fondée sur le principe de l’analyte unique utilisant une courbe de calibration commune. Cette stratégie génère un surcoût raisonnable compte tenu de la diversité des allergènes. Méthodes La validation de méthode selon la norme EN ISO 15189 a été réalisée pour la détermination des IgE spécifiques d’allergène avec la méthode immunofluoroenzymatique ImmunoCAP ® (Thermo Fisher Scientific, Phadia). Résultats Les données ont été produites par 25 laboratoires de CH et CHU français. Au total, les IgE spécifiques de 29 allergènes incluant des mélanges, des extraits et des composants moléculaires ont été analysées pour des concentrations comprises entre 0,1 et 100 kUA/L. Discussion Les performances analytiques (répétabilité, reproductibilité et justesse) du dosage des IgE spécifiques respectent les critères de validation de méthode attendus pour les examens de laboratoire automatisés et sont comparables quelles que soient la spécificité allergénique testée, la concentration sérique des IgE ou le laboratoire exécutant l’analyse. Conclusion Le dosage des IgE spécifiques d’allergène par la méthode immunofluoroenzymatique ImmunoCAP ® présente des performances analytiques permettant de satisfaire aux exigences de la norme EN ISO 15189 et d’assurer aux prescripteurs et aux patients la fiabilité des résultats fournis, via une stratégie d’accréditation « analyte unique ». La procédure d’accréditation validée par notre étude permet d’éviter un surcoût en réactifs estimé à un demi-million d’euros par automate. [ABSTRACT FROM AUTHOR]

Introduction Le syndrome hémolytique urémique atypique (SHUa) lié à un anticorps anti-facteur H (FH) est décrit essentiellement chez les enfants et adolescents. Moins de 10 cas sont rapportés chez l’adulte. Nous rapportons un cas traité par plasmaphérèses et rituximab. Patients et méthodes Un homme de 27 ans est hospitalisé pour une insuffisance rénale aiguë. À l’admission, les examens biologiques montrent : – une microangiopathie thrombotique avec anémie (7,3 g/dL) hémolytique (haptoglobine < 0,08 g/dL), thrombopénie (21 G/L) ; – une créatinine sérique à 242 μmol/L avec une hématurie microscopique et une protéinurie néphrotique. L’exploration du complément montre un C3 abaissé à 543 mg/L et un facteur B à 72 mg/L. Les anticorps anti-facteur H étaient positifs à 8200 UA (N < 100 unité arbitraires UA). La recherche de shigatoxin est négative. L’activité d’ADAMTS 13 est normale. Le traitement a consisté en : – plasmaphérèse quotidienne de j1 à j36 ; – corticothérapie (1 mg/kg/j) à dose décroissante (j5–M9) ; – 4 cures de rituximab (375 mg/m 2 ) à j5, 7, 13 et 17. Ce traitement a permis la négativation des anticorps anti-FH (j31), la normalisation de la créatinine, des plaquettes. Les anticorps anti-FH ont été positifs à j56 à 200 UA dans les suites d’une gastro-entérite. Une nouvelle injection de rituximab a été réalisée permettant sa négativation. À 17 mois du diagnostic, la créatinine sérique est de 87,5 μmol/L, plaquettes 189 G/L. Discussion et conclusion La prise en charge du SHUa par anti-facteur H nécessite des échanges plasmatiques et un traitement immunosuppresseur. Plusieurs traitements ont été proposés en dehors de l’éculizimab : cyclophosphamide, azathioprine, et rituximab. Ce dernier a été peu évalué mais a permis d’arrêter la plasmaphérèse dans un cas, et pourrait éviter les récidives en cas de transplantation rénale. L’association rituximab, corticoïdes et plasmaphérèse a permis la guérison de ce patient. En résumé, cette observation montre : – l’intérêt de la détection rapide des anti-facteur H même chez l’adulte ; – l’efficacité du rituximab en association aux plasmaphérèses. [ABSTRACT FROM AUTHOR]