Derek Chu

MethodsWe analyzed all consecutive OFCs done at one tertiary hospital and nine community clinics between January 1, 2018 to December 30, 2022. Eligible patients underwent an OFC to a single food allergen. Local ethics boards approved the study. We report preliminary findings of a subsample of participants.ResultsOf 450 out of 3380 total patients identified from 9 out of the 10 study sites, age was bimodally distributed with 314 children (less than 18 years old) being a mean (SD) age of 6.37 (5.45) years and 136 adults being 42.29 (17.70) years old. The most common food challenged were peanuts in children (n= 57, 18%) and shrimp in adults (n= 20, 15%). 18%(n= 80) of all participants reacted during their OFC. 29 required oral antihistamines meanwhile 4 required epinephrine administration. No serious adverse events occurred.ConclusionsIn this preliminary subsample of the overall cohort, 4 out of 5 …

This practice parameter update focuses on 7 areas in which there are new evidence and new recommendations. Diagnostic criteria for anaphylaxis have been revised, and patterns of anaphylaxis are defined. Measurement of serum tryptase is important for diagnosis of anaphylaxis and to identify underlying mast cell disorders. In infants and toddlers, age-specific symptoms may differ from older children and adults, patient age is not correlated with reaction severity, and anaphylaxis is unlikely to be the initial reaction to an allergen on first exposure. Different community settings for anaphylaxis require specific measures for prevention and treatment of anaphylaxis. Optimal prescribing and use of epinephrine autoinjector devices require specific counseling and training of patients and caregivers, including when and how to administer the epinephrine autoinjector and whether and when to call 911. If epinephrine is used …

Disparities in environmental and social determinants of health (DOH) are associated with morbidity in atopic dermatitis (AD). The socioecological model (SEM) is a framework that can be applied to better understand how such DOH impacts patients with AD. We include a case scenario of a remote Indigenous patient reflective of real-world situations of living with AD and examine relevant impact, gaps in knowledge, and further research needs. This review highlights a variety of social and environmental exposures as important DOH which must be addressed to achieve optimal management in AD. The “rainbow model” is a modified framework to help illustrate how complex environmental and social forces impact both AD presentation and therapeutic success. However, practical applications and outcome metrics for health promotion are limited. An inter- and transdisciplinary approach is paramount to address the …

BackgroundShort courses of adjunctive systemic corticosteroids are commonly used to treat acute urticaria and chronic urticaria flares (both with or without mast cell-mediated angioedema), but their benefits and harms are unclear.ObjectiveTo evaluate the efficacy and safety of treating acute urticaria or chronic urticaria flares with versus without systemic corticosteroids.MethodsWe searched MEDLINE, EMBASE, CENTRAL, CNKI, VIP, Wanfang, and CBM databases from inception to July 8, 2023 for randomized controlled trials of treating urticaria with versus without systemic corticosteroids. Paired reviewers independently screened records, extracted data, and appraised risk of bias with the Cochrane 2.0 tool. We did random effects meta-analyses of urticaria activity, itch severity and adverse events. We assessed certainty of the evidence using the GRADE approach.ResultsWe identified 12 randomized trials enrolling …

MethodsWe systematically identified randomized controlled trials addressing topical treatments for AD from MEDLINE, EMBASE, CENTRAL, CINAHL, LILACS, ICTRP, and GREAT to July 8, 2023. We excluded split-body trials. We performed Bayesian random-effects network meta-analyses on AD severity, itch severity, sleep disturbance, AD-related quality of life, AD exacerbations, and harms. We used GRADE to rate certainty of evidence. A multidisciplinary panel including patient partners determined thresholds for patient-important benefits and harms.ResultsWe analyzed 235 trials enrolling 46,315 patients (pediatrics and adults) and evaluated 69 unique interventions over a median 4 weeks for induction and 16 weeks for maintenance (overall range 1–156). To gain AD control, pimecrolimus improved the most outcomes, while tacrolimus, moderatepotency corticosteroids, delgocitinib, and ruxolitinib had …

BackgroundEgg is the third most common food allergy in children; however, data on pediatric egg-induced anaphylaxis are sparse.ObjectiveTo describe the clinical characteristics, management, and outcomes of pediatric egg-induced anaphylaxis.MethodsChildren presenting with anaphylaxis were recruited from 13 emergency departments as part of the Cross-Canada Anaphylaxis Registry, from which data on anaphylaxis triggered by egg were extracted. Multivariate logistic regression was used to determine factors associated with prehospital epinephrine autoinjector (EAI) use and to compare anaphylaxis triggered by egg with other triggers of food-induced anaphylaxis (FIA).ResultsWe recruited 302 children with egg-induced anaphylaxis. The mean age was 2.6 years (SD = 3.6), and 55.3% were male. Only 39.4% had previously been diagnosed with an egg allergy. Prehospital EAI use was 32.1%, but this was …

BackgroundGuidance addressing atopic dermatitis (AD) management, last issued in 2012 by the American Academy of Allergy, Asthma and Immunology/American College of Allergy, Asthma and Immunology Joint Task Force, requires updating as a result of new treatments and improved guideline and evidence synthesis methodology.ObjectiveTo produce evidence-based guidelines that support patients, clinicians, and other decision-makers in the optimal treatment of AD.MethodsA multidisciplinary guideline panel consisting of patients and caregivers, AD experts (dermatology and allergy/immunology), primary care practitioners (family medicine, pediatrics, internal medicine), and allied health professionals (psychology, pharmacy, nursing) convened, prioritized equity, diversity, and inclusiveness, and implemented management strategies to minimize influence of conflicts of interest. The Evidence in Allergy Group …

Asthma, rhinitis, and atopic dermatitis (AD) are interrelated clinical phenotypes that partly overlap in the human interactome. The concept of “one‐airway‐one‐disease,” coined over 20 years ago, is a simplistic approach of the links between upper‐ and lower‐airway allergic diseases. With new data, it is time to reassess the concept. This article reviews (i) the clinical observations that led to Allergic Rhinitis and its Impact on Asthma (ARIA), (ii) new insights into polysensitization and multimorbidity, (iii) advances in mHealth for novel phenotype definitions, (iv) confirmation in canonical epidemiologic studies, (v) genomic findings, (vi) treatment approaches, and (vii) novel concepts on the onset of rhinitis and multimorbidity. One recent concept, bringing together upper‐ and lower‐airway allergic diseases with skin, gut, and neuropsychiatric multimorbidities, is the “Epithelial Barrier Hypothesis.” This review determined …

Background Mixed and non‐IgE‐mediated food allergy is a subset of immune‐mediated adverse food reactions that can impose a major burden on the quality of life of affected patients and their families. Clinical trials to study these diseases are reliant upon consistent and valid outcome measures that are relevant to both patients and clinicians, but the degree to which such stringent outcome reporting takes place is poorly studied. Objective As part of the Core Outcome Measures for Food Allergy (COMFA) project, we identified outcomes reported in randomized clinical trials (RCT) of treatments for mixed or non‐IgE‐mediated food allergy. Design In this systematic review, we searched the Ovid, MEDLINE and Embase databases for RCTs in children or adults investigating treatments for food protein‐induced enterocolitis syndrome, food protein‐induced allergic proctocolitis, food protein‐induced enteropathy and …

Background: Gefapixant represents an emerging therapy for patients with RCC/UCC.Objectives: We aimed to evaluate the efficacy and safety of gefapixant for treatment of adults with RCC/UCC.Methods: We searched MEDLINE, EMBASE, CENTRAL, and the Web of Science from Nov 2014 to Dec 2022 for randomized controlled trials (RCTs). We included both parallel and crossover RCTs that compared, in patients with RCC/UCC, either gefapixant with placebo, or two or more doses of gefapixant with or without placebo. Pairs of independent reviewers screened abstracts and full texts of potentially eligible articles. After duplicate data extraction, we conducted frequentist random-effects dose-response meta-analyses. We assessed risk of bias among included studies using a revision of the Cochrane Risk of Bias 2.0 tool, and the certainty of evidence using GRADE.Results: We identified 10 RCTs including 2608 …

The European Academy of Allergy and Clinical Immunology (EAACI) is updating the Guidelines on Food Allergy Diagnosis. We aimed to undertake a systematic review of the literature with meta‐analyses to assess the accuracy of diagnostic tests for IgE‐mediated food allergy. We searched three databases (Cochrane CENTRAL (Trials), MEDLINE (OVID) and Embase (OVID)) for diagnostic test accuracy studies published between 1 October 2012 and 30 June 2021 according to a previously published protocol (CRD42021259186). We independently screened abstracts, extracted data from full texts and assessed risk of bias with QUADRAS 2 tool in duplicate. Meta‐analyses were undertaken for food‐test combinations for which three or more studies were available. A total of 149 studies comprising 24,489 patients met the inclusion criteria and they were generally heterogeneous. 60.4% of studies were in children …

BackgroundAtopic dermatitis (AD) is a common skin condition with multiple topical treatment options, but uncertain comparative effects. ObjectiveWe sought to systematically synthesize the benefits and harms of AD prescription topical treatments. MethodsFor the 2023 American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma, and Immunology Joint Task Force on Practice Parameters AD guidelines, we searched MEDLINE, EMBASE, CENTRAL, CINAHL, LILACS, ICTRP, and GREAT databases to September 5, 2022, for randomized trials addressing AD topical treatments. Paired reviewers independently screened records, extracted data, and assessed risk of bias. Random-effects network meta-analyses addressed AD severity, itch, sleep, AD-related quality of life, flares, and harms. The Grading of Recommendations Assessment, Development and Evaluation approach informed certainty of evidence ratings. We classified topical corticosteroids (TCS) using 7 groups—group 1 being most potent. This review is registered in the Open Science Framework (https://osf.io/q5m6s). ResultsThe 219 included trials (43,123 patients) evaluated 68 interventions. With high-certainty evidence, pimecrolimus improved 6 of 7 outcomes—among the best for 2; high-dose tacrolimus (0.1%) improved 5—among the best for 2; low-dose tacrolimus (0.03%) improved 5—among the best for 1. With moderate- to high-certainty evidence, group 5 TCS improved 6—among the best for 3; group 4 TCS and delgocitinib improved 4—among the best for 2; ruxolitinib improved 4—among the best for 1; group 1 TCS improved 3—among the best …

Staphylococcus aureus is a known trigger and cause of infectious complications in atopic dermatitis (AD). Various antiseptics have been used in an attempt to decrease the burden of S. aureus in AD. In this Commentary, we present the evidence for and against some of the commonly used antiseptics in clinical and research settings. These agents remain attractive as an adjunct therapy for AD owing to their relative low cost and potential benefits of reducing S. aureus. Although a number of studies have evaluated the use of dilute bleach, its mechanisms remain controversial. A higher concentration of bleach than the commonly used 0.005% is likely needed for its anti–S. aureus effect. Silver-coated textiles have demonstrated anti–S. aureus effects in various studies; however, their efficacy and side effects in AD remain to be confirmed. Other antiseptics including chlorhexidine, triclosan, and triclocarban are also …

MethodsChildren under 18 years of age presenting with wheat-induced anaphylaxis to seven EDs between 2011 and 2021 were enrolled in the Cross-Canada Anaphylaxis REgistry (C-CARE). A standardized recruitment form provided information on symptoms, triggers, comorbidities, and anaphylaxis management. Multivariate logistic regression was performed to identify factors associated with pre-ED epinephrine use.ResultsAmong N= 113 cases of wheat-induced anaphylaxis, bread was the most common trigger (20.4%; 23/113), followed by pasta and cereal. The median age was 5.4 (Interquartile range: 1.7, 9.0) years, and 64.6% were males. 15.0% were severe reactions (including cyanosis, desaturation, or cardiorespiratory collapse). Mucocutaneous symptoms, notably pruritus, urticaria, and angioedema, were most common (71.7%, 44.3%, and 39.8%, respectively). 52.2% occurred at home, 20.4% at school …

Background and aimsWith an increasing number of Clinical Practice Guidelines (CPGs) addressing primary prevention of food allergy and atopic dermatitis, it is timely to undertake a comprehensive assessment of the quality and consistency of recommendations and evaluation of their implementability in different geographical settings.MethodsWe systematically reviewed CPGs from 8 international databases and extensive website searches. Seven reviewers screened records in any language and then used the AGREE II and AGREE REX instruments to critically appraise CPGs published between January 2011 and April 2022.ResultsOur search identified 2138 relevant articles, of which 30 CPGs were eventually included. Eight (27%) CPGs were shortlisted based on our predefined quality criteria of achieving scores >70% in the “Scope and Purpose” and “Rigour of Development” domains of the AGREE II …

BackgroundEpinephrine is the first-line treatment for anaphylaxis but is often replaced with antihistamines or corticosteroids. Delayed epinephrine administration is a risk factor for fatal anaphylaxis. Convincing data on the role of antihistamines and corticosteroids in anaphylaxis management are sparse.ObjectiveTo establish the impact of prehospital treatment with epinephrine, antihistamines, and/or corticosteroids on anaphylaxis management.MethodsPatients presenting with anaphylaxis were recruited prospectively and retrospectively in 10 Canadian and 1 Israeli emergency departments (EDs) between April 2011 and August 2022, as part of the Cross-Canada Anaphylaxis REgistry. Data on anaphylaxis cases were collected using a standardized form.Primary outcomes were uncontrolled reactions (>2 doses of epinephrine in ED), no prehospital epinephrine use, use of intravenous fluids in ED, and hospital …

Assessing the certainty of evidence from network meta-analyses using the GRADE (grading of recommendations, assessment, development, and evaluations) approach requires not only a thorough understanding of the methods but also substantial workload for raters. This article describes how implementing practical strategies (including rule setting and automation) can facilitate efficient application of the GRADE approach to rating certainty of evidence in network meta-analyses while maintaining rigor. This article describes a stepwise strategy for proceeding through the process, including assessment of the certainty of direct, indirect, and NMA estimates; developing directions for each step in the process; implementation of rules to improve robustness of information appraisal to reduce workload; and alternatives for automation of some of the required steps. The presented approach includes a detailed description of …

Cow's milk allergy is rare in exclusively breastfed infants. To support the continuation of breastfeeding an infant after diagnosis with a cow's milk allergy, it is critical to examine the evidence for and against any form of cow's milk elimination diet for lactating mothers. In this narrative review, we highlight the lack of high-quality evidence, hence subsequent controversy, regarding whether the minuscule quantities of cow's milk proteins detectable in human milk cause infant cow's milk allergy symptoms. Current clinical practice recommendations advise a 2–4 week trial of maternal cow's milk dietary elimination for: a) IgE-mediated cow's milk allergy only if the infant is symptomatic on breastfeeding alone; b) non-IgE-mediated associated symptoms only if the history and examination strongly suggest cow's milk allergy; and c) infants with moderate to severe eczema/atopic dermatitis, unresponsive to topical steroids and …

ImportanceGefapixant represents an emerging therapy for patients with refractory or unexplained chronic cough.ObjectiveTo evaluate the efficacy and tolerability of gefapixant for the treatment of adults with refractory or unexplained chronic cough.Data SourcesMEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Web of Science from November 2014 to July 2023.Study SelectionTwo reviewers independently screened for parallel and crossover randomized clinical trials (RCTs) that compared, in patients with refractory or unexplained chronic cough, either gefapixant with placebo, or 2 or more doses of gefapixant with or without placebo.Data Extraction and SynthesisTwo reviewers independently extracted data. A frequentist random-effects dose-response meta-analysis or pairwise meta-analysis was used for each outcome. The GRADE (Grading of Recommendations, Assessment, Development …

MethodsWe systematically identified randomized controlled trials (RCT), comparative, and non-comparative non-randomized studies (NRS) from inception to June 6, 2022, from MEDLINE, EMBASE, GREAT, LILACS, ICTRP, FDA, EMA, company registers, and relevant citations. We included studies in any language addressing the risk of cancer in patients with AD exposed to TCIs for greater than 3 weeks. We excluded split-body studies. We conducted a random-effects Bayesian meta-analysis and used GRADE to rate the certainty of evidence. A multidisciplinary panel including patient partners determined thresholds for important risks.ResultsWe analyzed 121 studies (52 RCTs, 69 NRS) including 3.4 million patients followed for a mean of 11 months (range 0.7–150). The absolute risk of any cancer with TCI exposure was neither different from controls (absolute risk: 4.70 per 1000 with TCI versus 4.56 per 1000 …