Derek Chu

McMaster University | McMaster · Department of Medicine

Background Allergen exposure at lung and gut mucosae can lead to aberrant TH2 immunity and allergic disease. The epithelium-associated cytokines thymic stromal lymphopoietin (TSLP), IL-25, and IL-33 are suggested to be important for the initiation of these responses. Objective We sought to investigate the contributions of TSLP, IL-25, and IL-33 in...

Determining the cellular and molecular phenotypes of inflammation in asthma can identify patient populations that may best benefit from targeted therapies. Although elevated IL-6 and polymorphisms in IL-6 signalling are associated with lung dysfunction in asthma, it remains unknown if elevated IL-6 levels are associated with a specific cellular inf...

Background A number of food allergies (e.g. fish, shellfish, nuts) are lifelong, without any disease-transforming therapies and unclear in their underlying immunology. Clinical manifestations of food allergy are largely mediated by IgE. Although persistent IgE titres have conventionally been attributed to long-lived IgE+ plasma cells (PCs), this h...

Background: Supplemental oxygen is often administered liberally to acutely ill adults, but the credibility of the evidence for this practice is unclear. We systematically reviewed the efficacy and safety of liberal versus conservative oxygen therapy in acutely ill adults. Methods: In the Improving Oxygen Therapy in Acute-illness (IOTA) systematic r...

Background: Oral immunotherapy is an emerging experimental treatment for peanut allergy, but its benefits and harms are unclear. We systematically reviewed the efficacy and safety of oral immunotherapy versus allergen avoidance or placebo (no oral immunotherapy) for peanut allergy. Methods: In the Peanut Allergen immunotherapy, Clarifying the Evide...

Background Sesame can cause severe allergic reactions and is a priority allergen in Canada. Objective Our primary objective was to assess clinical characteristics and management of pediatric sesame-induced anaphylaxis and identify factors associated with epinephrine treatment. Methods Between 2011-2021, children with sesame-induced anaphylaxis pr...

Background: Different treatments exist for allergic rhinitis (AR), including pharmacotherapy and allergen immunotherapy (AIT), but they have not been compared using direct patient data (i.e., "real-world data"). Objective: To compare AR pharmacological treatments on (i) daily symptoms, (ii) frequency of use in co-medication, (iii) visual analogu...

Background Current forms of peanut oral immunotherapy (OIT) are associated with side effects and there is a lack of evidence addressing how to mitigate them. Objective To determine whether premedication with desloratadine and ranitidine results in fewer side effects during peanut OIT/desensitization. Methods 43 patients with peanut allergy (mean...

Objectives To evaluate the development and quality of actionable statements that qualify as good practice statements (GPS) reported in COVID-19 guidelines. Design and setting Systematic review . We searched MEDLINE, MedSci, China National Knowledge Infrastructure (CNKI), databases of Grading of Recommendations Assessment, Development and Evaluatio...

An evidence-based approach is considered the gold standard for health decision-making. Sometimes, a guideline panel might judge the certainty that the desirable effects of an intervention clearly outweigh its undesirable effects as high, but the body of supportive evidence is indirect. In such cases, the application of the Grading of Recommendation...

Background The prevalence of cow's milk allergy (CMA) is approximately 2–4.5% in infants and less than 0.5% in adults. Most children outgrow cow's milk allergy in early childhood, particularly that to the baked milk products. Immunotherapy with unheated cow's milk has been used as a treatment option for those who have not yet outgrown CMA, but the...

Background: Co-medication is common among patients with allergic rhinitis (AR), but its dimension and patterns are unknown. This is particularly relevant since AR is understood differently across European countries, as reflected by rhinitis-related search patterns in Google Trends. This study aims to assess AR co-medication and its regional patter...

Background: To summarise specific adverse effects of remdesivir, hydroxychloroquine and lopinavir/ritonavir in patients with COVID-19. Methods: We searched 32 databases through 27 October 2020. We included randomised trials comparing any of the drugs of interest to placebo or standard care, or against each other. We conducted fixed-effects pairw...

Background: Evidence regarding the effectiveness of allergen immunotherapy (AIT) on allergic rhinitis has been provided mostly by randomised controlled trials, with little data from real-life studies. Objective: To compare the reported control of allergic rhinitis symptoms in three groups of users of the MASK-air® app: those receiving sublingual...

Background: Bleach bathing is frequently recommended to treat atopic dermatitis (AD), but its efficacy and safety is uncertain. Objective: Systematically synthesize randomized controlled trials (RCTs) addressing bleach baths for AD. Methods: We searched MEDLINE, EMBASE, CENTRAL, GREAT from inception to December 29, 2021, for RCTs assigning patients...

Importance: Vaccination against SARS-CoV-2 is a highly effective strategy to prevent infection and severe COVID-19 outcomes. The best strategy for a second dose of vaccine among persons who had an immediate allergic reaction to their first SARS CoV-2 vaccination is unclear. Objective: To assess the risk of severe immediate allergic reactions (eg...

Since the World Allergy Organization (WAO) Diagnosis and Rationale against Cow's Milk Allergy (DRACMA) Guidelines were published 10 years ago, new evidence has accumulated about the diagnosis, therapy, and specific immunotherapy for cow's milk allergy (CMA). For this reason, WAO has felt the need to update the guidelines. We introduce here this upd...

Background There are a lack of data on seafood-induced anaphylaxis in children in Canada. Objective We aimed to assess the rate, clinical features, and management of seafood-induced anaphylaxis in children presenting to emergency departments across Canada. Methods Children with anaphylaxis were recruited at six emergency departments between 2011...

Aspirin-exacerbated respiratory disease (AERD) can be a frustratingly complex syndrome to treat. Until recently, standard medical and surgical therapies for patients’ asthma and chronic rhinosinusitis with nasal polyposis (CRSwNP) were the primary treatment modalities available, combined with either complete avoidance of all aspirin and non-steroid...

Background: The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of updating the guidelines on the diagnosis and management of food allergy. The existing guidelines are based on a systematic review of the literature until 30 September 2012. Therefore, a new systematic review must be undertaken to inform the new guideli...

Background: Bariatric surgery likely impairs the absorption of direct oral anticoagulants (DOACs). The optimal DOAC after bariatric surgery is unclear. Aims: To report on the safety and pharmacokinetics of DOACs after bariatric surgery in adults. Methods: We systematically searched MEDLINE, EMBASE, Cochrane Library, CINAHL and ClinicalTrials.gov fr...

Optimal evidence-based clinical practice requires systematic summaries of the best available evidence, including ratings of the quality of that evidence, and is facilitated by the availability of trustworthy guidelines. In this review, we describe the GRADE approach to rating quality of evidence and moving from evidence to recommendations using exa...

Objective To evaluate the efficacy and safety of antiviral antibody therapies and blood products for the treatment of novel coronavirus disease 2019 (covid-19). Design Living systematic review and network meta-analysis, with pairwise meta-analysis for outcomes with insufficient data. Data sources WHO covid-19 database, a comprehensive multilingua...

Background: Chronic rhinosinusitis with nasal polyposis (CRSwNP) is an inflammatory condition of the upper airways. Optimal management is unclear. Objective: To compare the effects of monoclonal antibodies and ASA desensitization (ASA-D) for treatment of CRSwNP. Methods: We searched MEDLINE, EMBASE, CENTRAL, ICTRP, FDA and EMA databases from i...

Objectives: To propose a taxonomy and framework that identifies and presents actionable statements in guidelines. Study design and setting: We took an iterative approach reviewing case studies of guidelines produced by the World Health Organization and the American Society of Hematology to develop an initial conceptual framework. We then tested...

Background There are a lack of disease-modifying treatments for peanut allergy, which is lifelong in most instances. Oral immunotherapy has remained at the forefront of prospective treatments, though its efficacy is consistently undermined by the risk of adverse reactions and meager sustained effects. Aim This review discusses the current state of...

Objective This article describes GRADE guidance for assessing imprecision when rating the certainty of the evidence from network meta-analysis. Study design and setting A project group within the GRADE working group conducted iterative discussions, computer simulations, and presentations at GRADE working group meetings to produce and obtain approv...

Food allergies are antigen-driven diseases that can lead to IgE-mediated reactions of immediate hypersensitivity (eg. anaphylaxis triggered by a single food), or non-IgE reactions of delayed hypersensitivity such as eosinophilic esophagitis (EoE; eg. inability to eat multiple foods manifesting as abdominal pain, choking, dysphagia, vomiting, reflux...

Network meta‐analyses (NMAs) simultaneously estimate effects of multiple possible treatment options for a given clinical presentation. For allergists to benefit optimally from NMAs they must understand the process and be able to interpret the results. Through a worked example published in Pediatric Allergy and Immunology, we summarize how to identi...

Concerns for anaphylaxis may hamper SARS-CoV-2 immunization efforts. We convened a multi-disciplinary group of international experts in anaphylaxis comprised of allergy, infectious disease, emergency medicine, and front-line clinicians to systematically develop recommendations regarding SARS-CoV-2 vaccine immediate allergic reactions. Medline, EMBA...

Allergen immunotherapy (AIT), the gradually increasing repeated administration of high doses of allergens to allergic patients, offers the potential for immune tolerance against reactions to the natural exposures to specific allergens. AIT may lead to the long-lasting remission of allergic symptoms and is the only disease-modifying intervention in...

Background Observational comparative effectiveness studies in allergen immunotherapy (AIT) represent an important evidence source answering research questions that can be challenging to obtain from randomized controlled trials (RCTs), such as long-term benefits of AIT, the effects on asthma prevention and the onset of new allergen sensitizations. H...

Importance The benefits and harms of adding long-acting muscarinic antagonists (LAMAs) to inhaled corticosteroids (ICS) and long-acting β2-agonists (LABAs) for moderate to severe asthma remain unclear. Objective To systematically synthesize the outcomes and adverse events associated with triple therapy (ICS, LABA, and LAMA) vs dual therapy (ICS pl...

Food allergy management in child care centers and schools is a controversial topic, for which evidence-based guidance is needed. Following the Grading of Recommendations Assessment, Development, and Evaluation approach, we conducted systematic literature reviews of the anticipated health effects of selected interventions for managing food allergy i...

Objective: To determine and compare the effects of drug prophylaxis on SARS-CoV-2 infection and covid-19. Design: Living systematic review and network meta-analysis. Data sources: World Health Organization covid-19 database, a comprehensive multilingual source of global covid-19 literature to 25 March 2021, and six additional Chinese databases...

Older adults, especially men and/or those with diabetes, hypertension and/or obesity, are prone to severe COVID‐19. In some countries, older adults, particularly those residing in nursing homes, have been prioritised to receive COVID‐19 vaccines due to high risk of death. In very rare instances,the COVID‐19 vaccines can induce anaphylaxis, and the...

Background Although there are many asymptomatic patients, one of the problems of COVID‐19 is early recognition of the disease. COVID‐19 symptoms are polymorphic and may include upper respiratory symptoms. However, COVID‐19 symptoms may be mistaken withthe common cold or allergic rhinitis. An ARIA‐EAACI study group attempted to differentiate upper r...

Background Data are sparse regarding clinical characteristics and management of fruit-induced anaphylaxis Objective To assess clinical characteristics and management of patients with fruit-induced anaphylaxis and determine factors associated with severe reactions and epinephrine use. Methods Over 9 years, children and adults presenting with anaph...

Objective To determine and compare the effects of drug prophylaxis on severe acute respiratory syndrome coronavirus virus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (covid-19). Design Living systematic review and network meta-analysis. Data sources WHO covid-19 database, a comprehensive multilingual source of global covid-19 literature t...

Background: Although there is a considerable body of knowledge about allergen immunotherapy (AIT), there is a lack of data on the reliability of real-world evidence (RWE) in AIT, and consequently, a lack of information on how AIT effectively works in real life. Methods: To address the current unmet need for an appraisal of the quality of RWE in...

In 2 randomized studies addressing peanut allergy (Canada-Food Allergy Risk Management 1 [NCT01812798] and Peanut Immunotherapy Starting in Canada, Evaluation and DiScovery [NCT0 1601522]), we quantified peanut allergen thresholds to food challenge using Bayesian stacked model averaging to inform policy and clinical practice. About 50% of patients...

Although there is a considerable body of knowledge about allergen immunotherapy (AIT), there is a lack of data on the reliability of real-world evidence (RWE) in AIT and consequently, a lack of information on how AIT effectively works in real life. To address the current unmet need for an appraisal of the quality of RWE in AIT, the European Academy...

The rapidly unfolding Coronavirus Disease of 2019 (COVID-19) pandemic and an ever-increasing volume of relevant literature presents considerable strain for decision makers. Those decision makers are interested in information not only about benefits and harms of interventions but also contextual information such as people’s values and preferences, c...

Background: IgE production against innocuous food antigens can result in anaphylaxis, a severe life-threatening consequence of allergic reactions. The maintenance of IgE immunity is primarily facilitated by IgG + memory B cells (MBCs), as IgE + MBCs and IgE + plasma cells are extremely scarce and short-lived, respectively. Objective:To investigate...

Introduction In an attempt to improve outcomes for patients with coronavirus disease 19 (COVID-19), several drugs, such as remdesivir, hydroxychloroquine (with or without azithromycin), and lopinavir/ritonavir, have been evaluated for treatment. While much attention focuses on potential benefits of these drugs, this must be weighed against their ad...

An amendment to this paper has been published and can be accessed via the original article.

Objective: To propose an approach for developing trustworthy recommendations as part of urgent responses (1-2 weeks) in the clinical, public health, and health systems fields. Study design and setting: We conducted a review of the literature, outlined a draft approach, refined the concept through iterative discussions, a workshop by the GRADE Rapi...

Background: It is not established whether the risk of anaphylaxis induced by peanuts or tree nuts in children increases at specific times of the year. We aimed to evaluate the risk of peanut-and tree-nut-induced anaphylaxis during certain cultural holidays in Canadian children. Methods: We collected data on confirmed pediatric cases of anaphylax...

Large differences in COVID‐19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbag...

Given the burden of disease and the consequences of a diagnosis of peanut allergy, it is important that peanut allergy be accurately diagnosed so that an appropriate treatment plan can be developed. However, a test that indicates there is peanut sensitization present (e.g., a “positive” test) is not always associated with clinical reactivity. This...

Objective To compare the effects of treatments for coronavirus disease 2019 (covid-19). Design Living systematic review and network meta-analysis. Data sources US Centers for Disease Control and Prevention COVID-19 Research Articles Downloadable Database, which includes 25 electronic databases and six additional Chinese databases to 20 July 2020....

Digital anamorphosis is used to define a distorted image of health and care that may be viewed correctly using digital tools and strategies. MASK digital anamorphosis represents the process used by MASK to develop the digital transformation of health and care in rhinitis.It strengthens the ARIA change management strategy in the prevention and manag...

Severe asthma imposes a significant burden on patients, families and healthcare systems. Management is difficult, due to disease heterogeneity, comorbidities, complexity in care pathways and differences between national or regional healthcare systems. Better understanding of the mechanisms has enabled a stratified approach to the management of seve...

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19 and is spread person-to-person through close contact. We aimed to investigate the effects of physical distance, face masks, and eye protection on virus transmission in health-care and non-health-care (eg, community) settings. Methods We did a systematic review...

Background: Mechanical ventilation is used to treat respiratory failure in coronavirus disease 2019 (COVID-19). Purpose: To review multiple streams of evidence regarding the benefits and harms of ventilation techniques for coronavirus infections, including that causing COVID-19. (PROSPERO registration: CRD42020178187). Data sources: 21 standar...

Introduction Proper strategies to minimise the risk of infection in individuals handling the bodies of deceased persons infected with 2019 novel coronavirus (2019-nCoV) are urgently needed. The objective of this study was to systematically review the literature to scope and assess the effects of specific strategies for the management of the bodies....

Introduction: There are few large-scale studies assessing the true risk of epinephrine use during anaphylaxis in adults. We aimed to assess the demographics, clinical characteristics, and secondary effects of epinephrine treatment and to determine factors associated with major and minor secondary effects associated with epinephrine use among adults...

IgE production against innocuous antigens can lead to life-threatening reactions such as anaphylaxis. While IgE levels drastically decline with strict allergen avoidance, the ability to regenerate IgE can persist for a lifetime, as is the case for peanut allergy. The mechanism by which IgE regenerates remains unresolved. A novel culture system and...