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Résumé La prise en charge des réactions anaphylactiques périopératoires répond à des recommandations spécifiques élaborées sous l’égide de la SFAR et de la SFA et révisées en 2011. En France, l’incidence des réactions anaphylactiques d’origine allergique est estimée à 100,6 [76,2–125,3]/million d’anesthésies dans la population générale. Chez l’adulte, les substances les plus fréquemment incriminées sont les curares, suivis des antibiotiques et des colorants. Les réactions au latex sont en nette régression. La majorité des réactions apparaît dans les minutes suivant l’injection intraveineuse des produits. Lorsque la symptomatologie est d’apparition plus tardive, au cours de la période d’entretien de l’anesthésie, une allergie au latex, à un colorant, un antiseptique ou aux produits de remplissage doit être évoquée. L’expression clinique d’une réaction anaphylactique est de gravité variable. Les signes cliniques initiaux les plus fréquemment rapportés sont l’absence de pouls, un érythème, une difficulté de ventilation, une désaturation ou une baisse de la pression télé-expiratoire de CO 2 . Les signes cutanés peuvent parfois être absents. Le diagnostic du mécanisme de la réaction repose sur le dosage des médiateurs (tryptase, histamine), au moment de la réaction. En cas d’allergie, l’identification de l’agent responsable se fait par la mise en évidence d’IgE spécifiques au moment de la réaction ou à distance et sur la réalisation de tests cutanés 6 semaines après la réaction. Le traitement repose sur l’interruption de l’administration de l’allergène lorsqu’elle est possible, sur la prescription d’adrénaline à dose titrée en fonction de la gravité clinique et de la réponse au traitement et sur le remplissage vasculaire. Anaphylactic reactions occurring during the perioperative period should be investigated and treated in compliance with the guidelines published by the SFAR and the SFA in 2011. In France, the estimated incidence of allergic reactions is 100.6 [76.2–125.3]/million procedures. In adults, the most frequently incriminated substances are neuromuscular blocking agents, followed by antibiotics and dyes. In most cases, clinical symptoms occur within minutes of intravenous administration of treatments. When symptoms are delayed and occur during the surgical procedure, a reaction involving latex, a vital dye, an antiseptic or a volume-expansion fluid should be suspected. Reaction severity may vary. The most frequently reported initial symptoms are pulselessness, erythema, increased airway pressure, desaturation and decreased end-tidal CO 2 . Clinical symptoms may occur as an isolated condition, making proper diagnosis difficult. Identification of the reaction mechanism relies on determination of mediators (tryptase, histamine) at the time of the reaction. In the event of an allergic reaction, the causative drug may be identified by the detection of specific IgE using immunoassays or by skin tests performed 6 weeks after the reaction. Treatment is based on suspension of allergen administration, on administration of epinephrine carefully titrated as a function of the severity of symptoms and on volume expansion. [ABSTRACT FROM AUTHOR]

Background: Kiwifruit is a common cause of food allergy. Symptoms range from mild to anaphylactic reactions. Objective: We sought to elucidate geographic differences across Europe regarding clinical patterns and sensitization to kiwifruit allergens. Factors associated with the severity of kiwifruit allergy were identified, and the diagnostic performance of specific kiwifruit allergens was investigated. Methods: This study was part of EuroPrevall, a multicenter European study investigating several aspects of food allergy. Three hundred eleven patients with kiwifruit allergy from 12 countries representing 4 climatic regions were included. Specific IgE to 6 allergens (Act d 1, Act d 2, Act d 5, Act d 8, Act d 9, and Act d 10) and kiwifruit extract were tested by using ImmunoCAP. Results: Patients from Iceland were mainly sensitized to Act d 1 (32%), those from western/central and eastern Europe were mainly sensitized to Act d 8 (pathogenesis-related class 10 protein, 58% and 44%, respectively), and those from southern Europe were mainly sensitized to Act d 9 (profilin, 31%) and Act d 10 (nonspecific lipid transfer protein, 22%). Sensitization to Act d 1 and living in Iceland were independently and significantly associated with severe kiwifruit allergy (odds ratio, 3.98 [P = .003] and 5.60 [P < .001], respectively). Using a panel of 6 kiwifruit allergens in ImmunoCAP increased the diagnostic sensitivity to 65% compared with 20% for skin prick tests and 46% ImmunoCAP using kiwi extract. Conclusion: Kiwifruit allergen sensitization patterns differ across Europe. The use of specific kiwifruit allergens improved the diagnostic performance compared with kiwifruit extract. Sensitization to Act d 1 and living in Iceland are strong risk factors for severe kiwifruit allergy. [ABSTRACT FROM AUTHOR]

Background: Anaphylactic reactions caused by bites of the European pigeon tick Argas reflexus are repeatedly reported. This soft-backed tick is a parasite of wild pigeons colonizing urban buildings and houses. Occasionally the ticks can bite human beings, inducing anaphylactic reactions in sensitized patients. Objective: Our aim was to characterize the major allergen implicated in a series of anaphylactic reactions caused by Argas bites and to produce the allergen as recombinant protein for diagnostic purposes. Methods: Protein extracts were prepared from whole A reflexus bodies, and IgE immunoblots were performed with sera from 13 patients who had an anaphylactic reaction with pigeon tick bites. A cDNA expression library was constructed from whole ticks and screened with a polyclonal rabbit antiserum raised against the major allergen. Results: The cDNA coding for the dominant allergen Arg r 1 could be isolated. It encodes a protein belonging to the lipocalin family. Allergenicity of the recombinant Arg r 1 was confirmed by immunoblot, ELISA, and intradermal skin tests. Conclusion: The dominant allergen of A reflexus has been isolated and the corresponding cDNA cloned. The recombinant protein, a lipocalin, was expressed in Escherichia coli and was shown to be immunoreactive in vitro and in vivo. Recombinant Arg r 1 was used as a diagnostic tool in a series of anaphylactic reactions caused by pigeon tick bites. [ABSTRACT FROM AUTHOR]