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...

Introduction: Anaphylaxis is an acute life-threatening allergy, most commonly provoked by food, venom, or drugs. There is limited data regarding differences in symptomatology between anaphylaxis provoked by different triggers. This study aimed to assess sociodemographic characteristics, clinical symptoms, and management of anaphylaxis, according to...

This European Academy of Allergy and Clinical Immunology (EAACI) guideline provides recommendations for the management of IgE‐mediated food allergy and was developed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. Following the confirmation of IgE‐mediated food allergy diagnosis, allergen avoidance an...

Importance The optimal inhaled reliever therapy for asthma remains unclear. Objective To compare short-acting β agonists (SABA) alone with SABA combined with inhaled corticosteroids (ICS) and with the fast-onset, long-acting β agonist formoterol combined with ICS for asthma. Data Sources The MEDLINE, Embase, and CENTRAL databases were searched fr...

Background Patients known for anaphylaxis are advised to always carry 2 epinephrine auto-injectors (EAI) with them. With epinephrine being the first-line treatment for anaphylaxis, current guidelines recommend prompt EAI administration, followed by observation in the emergency department (ED) for 4 hours. Data supporting transfer to the ED in all c...

Background Precautionary Allergen (“may contain”) Labelling (PAL) is used by industry to communicate potential risk to food-allergic individuals posed by unintended allergen presence (UAP). In 2014, the World Allergy Organization (WAO) highlighted that PAL use was increasing, but often applied inconsistently and without regulation — which reduces i...

Objective Eczema is the most burdensome skin condition worldwide and topical anti‐inflammatory treatments are commonly used to control symptoms. The relative effectiveness and safety of different topical anti‐inflammatory treatments is uncertain. Design Network meta‐analysis performed within a Cochrane systematic review to compare and statisticall...

Background Cow's milk allergy (CMA) is the most complex and common food allergy in infants. Elimination of cow's milk from the diet and replacement with a specialized formula for infants with cow's milk allergy who cannot be breastfed is an established approach to minimize the risk of severe allergic reactions while avoiding nutritional deficiencie...

Background: Eczema (atopic dermatitis) is the most burdensome skin condition worldwide and cannot currently be prevented or cured. Topical anti-inflammatory treatments are used to control eczema symptoms, but there is uncertainty about the relative effectiveness and safety of different topical anti-inflammatory treatments. Objectives: To compare...

Cow's milk allergy (CMA) is one of the most common presentations of food allergy in early childhood. Management of CMA involves individualized avoidance of cow's milk and other mammalian milk and foods containing these. Optimal elimination of cow's milk avoidance includes: label reading; information about safe and nutritious substitute foods; appro...

This Viewpoint discusses the updated guidelines from the American Academy of Allergy, Asthma, and Immunology (AAAAI)/American College of Allergy, Asthma and Immunology (ACAAI) Joint Task Force on atopic dermatitis (eczema) management.

Background Cow's milk allergy (CMA) is the most common food allergy in infants. The replacement with specialized formulas is an established clinical approach to ensure adequate growth and minimize the risk of severe allergic reactions when breastfeeding is not possible. Still, given the availability of multiple options, such as extensively hydrolyz...

Background IgE‐mediated food allergy (FA) is a global health concern with substantial individual and societal implications. While diverse intervention strategies have been researched, inconsistencies in reported outcomes limit evaluations of FA treatments. To streamline evaluations and promote consistent reporting, the Core Outcome Measures for Foo...

Background: IgE-mediated food allergy (FA) is a global health concern with substantial individual and societal implications. While diverse intervention strategies have been researched, inconsistencies in reported outcomes limit evaluations of FA treatments. To streamline evaluations and promote consistent reporting, the Core Outcome Measures for Fo...

Background: IgE-mediated food allergy (FA) is a global health concern with substantial individual and societal implications. While diverse intervention strategies have been researched, inconsistencies in reported outcomes limit evaluations of FA treatments. To streamline evaluations and promote consistent reporting, the Core Outcome Measures for...

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 Emba...

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,...

Background Breastfeeding has long been associated with numerous benefits for both mothers and infants. While some observational studies have explored the relationship between breastfeeding and mental health outcomes in mothers and children, a systematic review of the available evidence is lacking. The purpose of this study is to systematically eval...

This European Academy of Allergy and Clinical Immunology guideline provides recommendations for diagnosing IgE‐mediated food allergy and was developed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. Food allergy diagnosis starts with an allergy‐focused clinical history followed by tests to determine I...

Importance: Gefapixant represents an emerging therapy for patients with refractory or unexplained chronic cough. Objective: To evaluate the efficacy and tolerability of gefapixant for the treatment of adults with refractory or unexplained chronic cough. Data sources: MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Web of S...

Background: Atopic dermatitis (AD) is an inflammatory skin condition with multiple systemic treatments and uncertainty regarding their comparative impact on AD outcomes. Objective: We systematic synthesized the benefits and harms of AD systemic treatments. Methods: For the 2023 AAAAI/ACAAI JTFPP AD guidelines, we searched MEDLINE, EMBASE, CENT...

Background: Atopic dermatitis (AD) is a common skin condition with multiple topical treatment options, but uncertain comparative effects. Objectives: We systematically synthesized the benefits and harms of AD prescription topical treatments. Methods: For the 2023 AAAAI/ACAAI JTFPP AD guidelines, we searched MEDLINE, EMBASE, CENTRAL, CINAHL, LI...

Background: Epinephrine 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 is sparse. Objective: To establish the impact of p...

This rapid systematic review of evidence asks whether (i) wearing a face mask, (ii) one type of mask over another and (iii) mandatory mask policies can reduce the transmission of SARS-CoV-2 infection, either in community-based or healthcare settings. A search of studies published 1 January 2020–27 January 2023 yielded 5185 unique records. Due to a...

The Coronavirus Disease 2019 (COVID-19) pandemic has evolved over the past 3+ years, and strategies to prevent illness and treat infection have changed over time. As COVID-19 transitions from a pandemic to endemic infection, widespread non-pharmaceutical interventions such as mask mandates and governmental policies requiring social distancing have...

Background: The European Academy of Allergy and Clinical Immunology’s (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. Methods : We searched three databases (Cochrane CENTRAL (Trials),...

This guidance updates 2021 GRADE recomendations regarding immediate allergic reactions following COVID-19 vaccines and addresses re-vaccinating individuals with 1st dose allergic reactions and allergy testing to determine re-vaccination outcomes. Recent meta-analyses assessed the incidence of severe allergic reactions to initial COVID-19 vaccinatio...

Objective: This article describes considerations for addressing intransitivity when assessing the certainty of the evidence from network meta-analysis (NMA) using the GRADE approach. Intransitivity is induced by effect modification, i.e., when the magnitude of the effect between an intervention and outcome differs depending on the level of another...

We aimed to assess the impact of allocation concealment and blinding on the results of coronavirus disease 2019 (COVID-19) trials, using the World Health Organization COVID-19 database (to February 2022). We identified 488 randomized trials comparing drug therapeutics with placebo or standard care in patients with COVID-19. We performed random-effe...

Background and aims: With 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. Methods: We...

Biomarkers for the diagnosis, treatment and follow-up of patients with rhinitis and/or asthma are urgently needed. Although some biologic biomarkers exist in specialist care for asthma, they cannot be largely used in primary care. There are no validated biomarkers in rhinitis or allergen immunotherapy (AIT) that can be used in clinical practice. Th...

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 re...

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, bu...

Atopic dermatitis affects millions worldwide and is effectively managed by topical treatments, including topical calcineurin inhibitors, pimecrolimus and tacrolimus. In 2005 and 2011, the FDA released reviews associating topical calcineurin inhibitors with a theoretical cancer risk, albeit an uncertain association. We systematically reviewed the ri...

Importance Patient values and preferences can inform atopic dermatitis (AD) care. Systematic summaries of evidence addressing patient values and preferences have not previously been available. Objective To inform American Academy of Allergy, Asthma & Immunology (AAAAI)/American College of Allergy, Asthma and Immunology (ACAAI) Joint Task Force on...

Staphylococcus aureus (S. 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 a...

Background Anaphylaxis is an acute systemic and potentially fatal allergic reaction. In this study, we evaluated trends in yearly rates of anaphylaxis in a pediatric Emergency Department (ED) in Montreal, Canada. Methods A prospective and retrospective recruitment process was used to find families of children who had presented with anaphylaxis at...

MASK‐air®, a validated mHealth app (Medical Device regulation Class IIa) has enabled large observational implementation studies in over 58,000 people with allergic rhinitis and/or asthma. It can help to address unmet patient needs in rhinitis and asthma care. MASK‐air® is a Good Practice of DG Santé on digitally‐enabled, patient‐centred care. It is...

Objective To determine the efficacy and safety of awake prone positioning versus usual care in non-intubated adults with hypoxemic respiratory failure due to covid-19. Design Systematic review with frequentist and bayesian meta-analyses. Study eligibility Randomized trials comparing awake prone positioning versus usual care in adults with covid-1...

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease worldwide. AD begins before age five in 90% of cases and is associated with the development of comorbid conditions such as infections, environmental allergies, food allergies, asthma, anxiety/depression, and abnormalities in sleep, growth, and development. While personal ex...

For persons with immediate allergic reactions to mRNA COVID‐19 vaccines, skin testing (ST) to the vaccine/excipients (polyethylene glycol[PEG] and polysorbate 80 [PS]) has been recommended, but has unknown accuracy. To assess vaccine/excipient ST accuracy in predicting all‐severity immediate allergic reactions upon re‐vaccination, systematic review...

Introduction Data from mHealth apps can provide valuable information on rhinitis control and treatment patterns. However, in MASK‐air®, these data have only been analyzed cross‐sectionally, without considering the changes of symptoms over time. We analyzed data from MASK‐air® longitudinally, clustering weeks according to reported rhinitis symptoms....

Digital health is an umbrella term which encompasses eHealth and benefits from areas such as advanced computer sciences. eHealth includes mHealth apps, which offer the potential to redesign aspects of healthcare delivery. The capacity of apps to collect large amounts of longitudinal, real‐time, real‐world data enables the progression of biomedical...

These evidence-based guidelines support patients, clinicians, and other stakeholders in decisions about the use of intranasal corticosteroids (INCS), biologics, and aspirin therapy after desensitization (ATAD) for the management of chronic rhinosinusitis with nasal polyposis (CRSwNP). It is important to note that the current evidence on surgery for...

Background Atopic dermatitis is a prevalent condition in children and can be effectively managed with medications such as topical calcineurin inhibitors (pimecrolimus or tacrolimus). A key unresolved safety concern is whether use of topical calcineurin inhibitors is associated with cancer. We systematically reviewed the risk of cancer in patients w...

Introduction Atopic dermatitis (AD) affects millions worldwide and is effectively managed by topical treatments, including the topical calcineurin inhibitors (TCIs), pimecrolimus and tacrolimus. In 2005 and 2011, the FDA released reviews associating TCIs with theoretical cancer risk, albeit with uncertainty. We systematically reviewed the cancer ri...