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Background: The heterogeneity and lack of validation of existing severity scores for food allergic reactions limit standardization of case management and research advances. We aimed to develop and validate a severity score for food allergic reactions. Methods: Following a multidisciplinary experts consensus, it was decided to develop a food allergy severity score (FASS) with ordinal (oFASS) and numerical (nFASS) formats. oFASS with 3 and 5 grades were generated through expert consensus, and nFASS by mathematical modeling. Evaluation was performed in the EuroPrevall outpatient clinic cohort (8232 food reactions) by logistic regression with request of emergency care and medications used as outcomes. Discrimination, classification, and calibration were calculated. Bootstrapping internal validation was followed by external validation (logistic regression) in 5 cohorts (3622 food reactions). Correlation of nFASS with the severity classification done by expert allergy clinicians by Best‐Worst Scaling of 32 food reactions was calculated. Results: oFASS and nFASS map consistently, with nFASS having greater granularity. With the outcomes emergency care, adrenaline and critical medical treatment, oFASS and nFASS had a good discrimination (receiver operating characteristic area under the curve [ROC‐AUC]>0.80), classification (sensitivity 0.87–0.92, specificity 0.73–0.78), and calibration. Bootstrapping over ROC‐AUC showed negligible biases (1.0 × 10−6–1.23 × 10−3). In external validation, nFASS performed best with higher ROC‐AUC. nFASS was strongly correlated (R 0.89) to best‐worst scoring of 334 expert clinicians. Conclusion: FASS is a validated and reliable method to measure severity of food allergic reactions. The ordinal and numerical versions that map onto each other are suitable for use by different stakeholders in different settings. [ABSTRACT FROM AUTHOR]

Abstract: The accurate assessment and communication of the severity of acute allergic reactions are important to patients, clinicians, researchers, the food industry, and public health and regulatory authorities. Severity has different meanings to different stakeholders with patients and clinicians rating the significance of particular symptoms very differently. Many severity scoring systems have been generated, most focusing on the severity of reactions following exposure to a limited group of allergens. They are heterogeneous in format, none has used an accepted developmental approach, and none has been validated. Their wide range of outcome formats has led to difficulties with interpretation and application. Therefore, there is a persisting need for an appropriately developed and validated severity scoring system for allergic reactions that work across the range of allergenic triggers and address the needs of different stakeholder groups. We propose a novel approach to develop and then validate a harmonized scoring system for acute allergic reactions, based on a data‐driven method that is informed by clinical and patient experience and other stakeholders’ perspectives. We envisage two formats: (i) a numerical score giving a continuum from mild to severe reactions that are clinically meaningful and are useful for allergy healthcare professionals and researchers, and (ii) a three‐grade‐based ordinal format that is simple enough to be used and understood by other professionals and patients. Testing of reliability and validity of the new approach in a range of settings and populations will allow eventual implementation of a standardized scoring system in clinical studies and routine practice. [ABSTRACT FROM AUTHOR]

Background The European Academy of Allergy and Clinical Immunology ( EAACI) is in the process of developing the EAACI Guidelines on Allergen Immunotherapy ( AIT) for the management of insect venom allergy. To inform this process, we sought to assess the effectiveness, cost-effectiveness and safety of AIT in the management of insect venom allergy. Methods We undertook a systematic review, which involved searching 15 international biomedical databases for published and unpublished evidence. Studies were independently screened and critically appraised using established instruments. Data were descriptively summarized and, where possible, meta-analysed. Results Our searches identified a total of 16 950 potentially eligible studies; of which, 17 satisfied our inclusion criteria. The available evidence was limited both in volume and in quality, but suggested that venom immunotherapy ( VIT) could substantially reduce the risk of subsequent severe systemic sting reactions ( OR = 0.08, 95% CI 0.03-0.26); meta-analysis showed that it also improved disease-specific quality of life (risk difference = 1.41, 95% CI 1.04-1.79). Adverse effects were experienced in both the build-up and maintenance phases, but most were mild with no fatalities being reported. The very limited evidence found on modelling cost-effectiveness suggested that VIT was likely to be cost-effective in those at high risk of repeated systemic sting reactions and/or impaired quality of life. Conclusions The limited available evidence suggested that VIT is effective in reducing severe subsequent systemic sting reactions and in improving disease-specific quality of life. VIT proved to be safe and no fatalities were recorded in the studies included in this review. The cost-effectiveness of VIT needs to be established. [ABSTRACT FROM AUTHOR]

Background A major drawback of oral immunotherapy for food allergy is the possibility of severe side-effects. We assessed both safety and efficacy of a low allergenic hydrolysed egg (HydE) preparation used in a double-blind placebo-controlled randomized study in egg allergic children. Methods In a pilot multicentre study, 29 egg allergic patients (aged 1-5.5 years) were administered daily for 6 months 9 g HydE or placebo in a blinded, randomized manner. Safety was verified by oral food challenge to assess tolerance towards HydE at the start and efficacy by an open oral food challenge ( OFC, primary outcome) at the end. Additionally, changes in basophil activation and specific IgE and IgG4 were assessed. Results All egg allergic patients randomized to HydE ( n = 15) tolerated the full dose at day 1 and received the maintenance dose from the start at home. No statistically significant difference was observed on the final OFC (36% and 21% had a negative OFC in the treatment and placebo groups, respectively). Specific IgG4 levels increased, while both CD203c+ and CD63+ basophils decreased significantly more over time in the treatment than in the placebo group. Conclusions HydE can be regarded as a safe, low allergenic product to use in children allergic to egg. Although not significant, HydE given for 6 months increased numerically the proportion of patients becoming tolerant to egg. HydE induced a modulation of the immune response towards better tolerance. A longer treatment period and/or a higher dose may improve the clinical outcome and should be evaluated. [ABSTRACT FROM AUTHOR]

This document is the result of a consensus on the mechanisms of exercise-induced anaphylaxis (EIAn), an unpredictable and potentially fatal syndrome. A multidisciplinary panel of experts including exercise physiologists, allergists, lung physicians, paediatricians and a biostatistician reached the given consensus. Exercise-induced anaphylaxis (EIAn) describes a rare and potentially fatal syndrome in which anaphylaxis occurs in conjunction with exercise. The pathophysiological mechanisms underlying EIAn have not yet been elucidated although a number of hypotheses have been proposed. This review evaluates the validity of each of the popular theories in relation to exercise physiology and immunology. On the basis of this evidence, it is concluded that proposed mechanisms lack validity, and it is recommended that a global research network is developed with a common approach to the diagnosis and treatment of EIAn in order to gain sufficient power for scientific evaluation. [ABSTRACT FROM AUTHOR]

Background Perioperative allergic reactions to chlorhexidine are often severe and easily overlooked. Although rare, the prevalence remains unknown. Correct diagnosis is crucial, but no validated provocation model exists, and other diagnostic tests have never been evaluated. The aims were to estimate (i) the prevalence of chlorhexidine allergy in perioperative allergy and (ii) the specificity and sensitivity for diagnostic tests for chlorhexidine allergy. Methods We included all patients investigated for suspected perioperative allergic reactions in the Danish Anaesthesia Allergy Centre during 2004-2012. The following tests were performed: specific Ig E ( Immunocap®; Phadia AB, Sweden), histamine release test ( HR) ( RefLab Ap S, Denmark), skin prick test ( SPT) and intradermal test ( IDT). Positivity criteria were as follows: specific Ig E >0.35 k UA/l; HR class 1-12; SPT mean wheal diameter ≥3 mm; IDT mean wheal diameter ≥ twice the diameter of negative control. Chlorhexidine allergy was post hoc defined as a relevant clinical reaction to chlorhexidine combined with two or more positive tests. Based on this definition, sensitivity and specificity were estimated for each test. Results In total, 22 of 228 patients (9.6%) met the definition of allergy to chlorhexidine. Estimated sensitivity and specificity were as follows: specific Ig E (sensitivity 100% and specificity 97%), HR (sensitivity 55% and specificity 99%), SPT (sensitivity 95% and specificity 97%) and IDT (sensitivity 68% and specificity 100%). Conclusions In patients investigated for suspected perioperative allergic reactions, 9.6% were diagnosed with allergy to chlorhexidine. Using our definition of chlorhexidine allergy, the highest combined estimated sensitivity and specificity was found for specific IgE and SPT. [ABSTRACT FROM AUTHOR]

Nine cases of diclofenac hypersensitivity recorded by the Allergy Vigilance Network in France from 2002 to 2012 were studied. Data from history, symptoms, skin tests, basophil activation tests, and oral challenge ( OC) were recorded. Grade 3 severe anaphylactic reactions occurred in seven cases of nine. IgE-dependent anaphylaxis was confirmed in six cases: positive intradermal tests ( n = 4), a syndromic reaction during skin tests ( n = 1), and one case with grade 1 reaction and negative skin tests had an anaphylactic shock to the OC. A nonimmune reaction was suspected in one case. An IgE-dependent mechanism may be the predominant cause of adverse reactions to diclofenac. Allergy skin tests must be carried out sequentially at the recommended concentrations. BATs may be helpful because they can support the diagnosis of anaphylaxis. Given the risks of a direct challenge to diclofenac, OC to aspirin should be performed first to exclude a nonimmunologic hypersensitivity to NSAIDs. Tests for specific IgEs to most frequently used NSAIDs such as diclofenac and ibuprofen are urgently needed. [ABSTRACT FROM AUTHOR]

The author discusses the research "Standardized testing with chlorhexidine in perioperative allergy ? A large single centre evaluation" by M.S. Opstrup and colleagues, present within the issue. Topics discussed include analysis of patients with perioperative anaphylaxis by the Danish Anaesthesia Allergy Center (DAAC), the drugs and substances responsible for perioperative anaphylaxis, and the difficulty iin confirming allergy in the perioperative setting without a provocation test.