COVID-19 and celiac disease: A pathogenetic hypothesis for a celiac outbreak

No COVID-19 pandemic impact on incidence and clinical presentation of celiac disease in Italian children

AIM

We aimed to evaluate the impact of Coronavirus Disease-19 (COVID-19) pandemic on the incidence and clinical presentation of celiac disease (CD) in children.

METHODS

The diagnoses of CD were compared between the COVID-19 pandemic (from April 2020 to March 2022) and the pre-pandemic period (from April 2018 to March 2020) in three Italian Paediatric Gastroenterology centres (Varese, Como, Catanzaro). Electronic patient records were reviewed and additional information were collected through parental interview. The diagnosis of CD was made according to ESPGHAN criteria. SARS-CoV-2 infection was diagnosed based on pre-vaccination positive serum antibodies or nasopharyngeal swabs. Z test and chi-square were used for statistical analysis.

RESULTS

The overall number of paediatric diagnosis of CD did not differ between the two years pre-pandemic and pandemic periods (177 and 172 cases) in the three Italian participating centres. Clinical presentation of CD was also similar throughout the study periods. SARS-CoV-2 infection has been documented in 10.6% of children but only in 5.8% of these occurred before CD diagnosis.

CONCLUSION

Different to what reported for other autoimmune diseases, the incidence and presenting symptoms of CD in our paediatric population did not change during the COVID-19 pandemic compared to the previous 2 years.

HLA-DQ2/8 and COVID-19 in Celiac Disease: Boon or Bane

The SARS-CoV-2 pandemic continues to pose a global threat. While its virulence has subsided, it has persisted due to the continual emergence of new mutations. Although many high-risk conditions related to COVID-19 have been identified, the understanding of protective factors remains limited. Intriguingly, epidemiological evidence suggests a low incidence of COVID-19-infected CD patients. The present study explores whether their genetic background, namely, the associated HLA-DQs, offers protection against severe COVID-19 outcomes. We hypothesize that the HLA-DQ2/8 alleles may shield CD patients from SARS-CoV-2 and its subsequent effects, possibly due to memory CD4 T cells primed by previous exposure to human-associated common cold coronaviruses (CCC) and higher affinity to those allele's groove. In this context, we examined potential cross-reactivity between SARS-CoV-2 epitopes and human-associated CCC and assessed the binding affinity (BA) of these epitopes to HLA-DQ2/8. Using computational methods, we analyzed sequence similarity between SARS-CoV-2 and four distinct CCC. Of 924 unique immunodominant 15-mer epitopes with at least 67% identity, 37 exhibited significant BA to HLA-DQ2/8, suggesting a protective effect. We present various mechanisms that might explain the protective role of HLA-DQ2/8 in COVID-19-afflicted CD patients. If substantiated, these insights could enhance our understanding of the gene-environment enigma and viral-host relationship, guiding potential therapeutic innovations against the ongoing SARS-CoV-2 pandemic.

Investigating the Relationship Between COVID-19 and Celiac Disease. A Dual Research Approach

Background

Most evidence on the coronavirus disease 2019 (COVID-19) pandemic, has been obtained from web- or telephone-based surveys. In particular, few laboratory data, often incomplete, have been reported on the frequency of COVID-19-related serology at celiac disease (CD) diagnosis or on the effects of COVID-19 on the development of CD-specific autoimmunity.

Objectives

The objective of this retrospective cross-sectional case/control study was to: (1) evaluate the frequency of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in 78 children and adolescents at CD diagnosis (CD, 44 females, median age 7.4 years); (2) evaluate the frequency of IgA-anti-transglutaminase antibodies (IgA-tTGAbs) in 97 nonceliac patients (50 females, median age 9.0 years) who contracted SARS-CoV-2 infection during the pandemic (February-April 2021). As a control (CTRL) group, we analyzed 141 healthy subjects (79 females, median age 9.8 years) enrolled during the pandemic.

Methods

SARS-CoV-2 IgM- and IgG-antibodies were detected by chemiluminescent microparticle immunoassays. IgA-tTGAbs were detected by a fluid-phase radioimmunoassay.

Results

Six out of 78 (7.7%) CD patients tested positive for SARS-CoV-2Abs, with a frequency not significantly different from CTRL subjects (9.2%). None of the 97 nonceliac COVID-19 patients tested positive for IgA-tTG antibodies.

Conclusion

These 2 distinct research approaches showed (1) similar frequencies of SARS-CoV-2 immunoreactivities in CD patients and CTRL subjects and, (2) no ability of SARS-CoV-2 to induce a CD-specific immune response, at least in the 3-4 months following SARS-CoV-2 infection.

Viruses and celiac disease: what do we know ?

The aim of this review is to provide a comprehensive overview about the link between viruses and celiac disease. A systematic search on PubMed, Embase, and Scopus was conducted on March 07, 2023. The reviewers independently selected the articles and chose which articles to include. The review is a textual systemic review, and all relevant articles were included based on title and abstract. If there was a disagreement between the reviewers, they came to a consensus during deliberation sessions. A total of 178 articles were selected for the review and read in full; only part of them was retained. We found studies between celiac disease and 12 different viruses. Some of the studies were done only on small groups. Most studies were on pediatric population. Evidence for an association was found with several viruses (trigger or protective). It seems that only a part of the viruses could induce the disease. Several points are important to keep in mind: firstly, simple mimicry or that the virus induces a high level of TGA is not sufficient to promote the disease. Secondly, inflammatory background is necessary to induce CD with virus. Thirdly, IFN type 1 seems to have an important role. Some of the viruses are potential or known triggers like enteroviruses, rotaviruses, reoviruses, and influenza. Further studies are needed to better understand the role of viruses in celiac disease to better treat and prevent the disease.

Previous SARS-CoV-2 Infection Is Not Associated With Increased Celiac Disease Autoimmunity in Children and Adolescents

INTRODUCTION

Recent reports suggest severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections may increase the risk of celiac disease autoimmunity. This study aims to evaluate potential associations between coronavirus disease 2019 infection and tissue transglutaminase autoantibodies (TGA) immunoglobulin A.

METHODS

From 2020 to 2021, cross-sectional screening for SARS-CoV-2 antibodies and TGA was offered to 4,717 children in Colorado through the Autoimmunity Screening for Kids study. Multivariable logistic regression assessed association between previous SARS-CoV-2 infection and TGA positivity.

RESULTS

Previous SARS-CoV-2 infection was not associated with TGA positivity (odds ratio 1.02, 95% confidence interval 0.63-1.59; P = 0.95).

DISCUSSION

In this large-scale analysis, previous SARS-CoV-2 infection was not associated with celiac disease autoimmunity in Colorado children.

COVID-19 infection: a possible induction factor for development of autoimmune diseases?

Following the global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the importance of investigation of the pathogenesis and immunological characteristics of COVID-19 became quite clear. Currently, there are reports indicating that COVID-19 is able to induce autoimmune responses. Abnormal immune reactions are a cornerstone in the pathogenicity of both conditions. Detection of autoantibodies in COVID-19 patients may suggest a link between COVID-19 and autoimmunity. In this study, we focused on the similarities and possible differences between COVID-19 and autoimmune disorders to explore the relationship between them. Comparing the pathogenicity of SARS-CoV-2 infection with autoimmune conditions revealed significant immunological properties of COVID-19 including the presence of several autoantibodies, autoimmunity-related cytokines, and cellular activities that could be useful in future clinical studies aiming at managing this pandemic.

Coronavirus disease 2019 and gastrointestinal disorders in children

During the past 3 years, the coronavirus disease 2019 (COVID-19) pandemic has had a great impact on people all over the world. However, it has become evident that disease manifestations and severity differ across age groups. Most children have a milder disease course than adults but possibly more pronounced gastrointestinal (GI) symptoms. Given the child's developing immune system, the impact of COVID-19 on disease development may differ compared to adults. This study reviews the potential bi-directional relationship between COVID-19 and GI diseases in children, focusing on common pediatric conditions such as functional GI disorders (FGID), celiac disease (CeD), and inflammatory bowel disease (IBD). Children with GI diseases, in general, and CeD and IBD, in particular, do not seem to have an increased risk of severe COVID-19, including risks of hospitalization, critical care need, and death. While infections are considered candidate environmental factors in both CeD and IBD pathogenesis, and specific infectious agents are known triggers for FGID, there is still not sufficient evidence to implicate COVID-19 in the development of either of these diseases. However, given the scarcity of data and the possible latency period between environmental triggers and disease development, future investigations in this field are warranted.

The risk for celiac disease after Covid-19 infection

BACKGROUND

Celiac disease (CD) is an autoimmune disease leading to gastrointestinal symptoms and mineral deficiencies. The pathogenetic mechanisms, besides the clear HLA association, are elusive. Among environmental factors infections have been proposed. Covid-19 infection results in a systemic inflammatory response that often also involves the gastrointestinal tract. The aim of the present study was to investigate whether Covid-19 infection could increase the risk for CD.

PATIENTS AND METHODS

All patients, both children and adults, in the county Skåne (1.4 million citizens) in southern Sweden with newly diagnosed biopsy- or serology-verified CD or a positive tissue transglutaminase antibody test (tTG-ab) during 2016-2021 were identified from registries at the Departments of Pathology and Immunology, respectively. Patients with a positive Covid-19 PCR or antigen test in 2020 and 2021 were identified from the Public Health Agency of Sweden.

RESULTS

During the Covid-19 pandemic (March 2020 - December 2021), there were 201 050 cases of Covid-19 and 568 patients with biopsy- or serology-verified CD or a first-time positive tTG-ab tests, of which 35 patients had been infected with Covid-19 before CD. The incidence of verified CD and tTG-ab positivity was lower in comparison to before the pandemic (May 2018 - February 2020; 22.5 vs. 25.5 cases per 100 000 person-years, respectively, incidence rate difference (IRD) -3.0, 95% CI -5.7 - -0.3, p = 0.028). The incidence of verified CD and tTG-ab positivity in patients with and without prior Covid-19 infection was 21.1 and 22.4 cases per 100 000 person-years, respectively (IRD - 1.3, 95% CI -8.5-5.9, p = 0.75).

CONCLUSIONS

Our results indicate that Covid-19 is not a risk factor for CD development. While gastrointestinal infections seem to be an important part of the CD pathogenesis, respiratory infections probably are of less relevance.

COVID-19 and celiac disease: a review

The aim of this review is to broadly cover how the COVID-19 pandemic has affected individuals with celiac disease, including perceived risk, risk of contraction or severe infection, considerations regarding vaccination, access to gluten-free food during the pandemic, and possible long-term changes to the practice of celiac disease management spurred by the pandemic. While initially there was increased perceived risk about COVID-19 in the celiac disease population, studies have found that individuals with celiac disease are not at an increased risk of contracting or having a severe course compared to the general population. There is not yet evidence that COVID-19 infection will lead to an increase in celiac disease incidence, though more research on this topic with longer-term follow-up is necessary to make this determination. Limited access to in-person visits led to an increase in telemedicine, which was adopted swiftly by this patient population and may offer improved access in the long term. In summary, individuals with celiac disease do not appear to be at an increased risk of contracting COVID-19 or having a more severe disease course.

Coronavirus disease 2019 (COVID-19) in pediatric patients with autoimmune disorders

Coronavirus disease 2019 (COVID-19) infection in pediatric patients with autoimmune disorders is an area of particular concern since autoimmune diseases can increase the risk of complications from the virus. However, as the infection rates were significantly higher in adults compared to children, this at-risk group of children was relatively underrepresented in COVID-19 research. The underlying inflammatory basis of autoimmune diseases and medications that affect the immune system, such as corticosteroids, could increase the risk of severe infection in this group of patients. COVID-19 could reportedly lead to a variety of alterations in the immune system. These alterations are plausibly dependent on the underlying immune-mediated diseases or prior use of immunomodulatory drugs. Patients administrating immunomodulatory agents, especially those with severe immune system dysregulation, can experience severe symptoms of COVID-19. Nonetheless, receiving immunosuppressive medications can benefit patients by preventing cytokine storm syndromes and lung tissue damage, threatening outcomes of COVID-19.

CONCLUSION

In this review, we sought to evaluate the currently available literature on the impact of autoimmune disease and its related therapeutic approaches on the COVID-19 infection course of disease in children and reflect on the gaps in the evidence and the need for further research in this field.

WHAT IS KNOWN

• The majority of children infected with COVID-19 demonstrate mild to moderate clinical manifestations compared to adults, whereas those children with pre-existing autoimmune conditions are at a greater risk for severe symptoms. •There is currently limited understanding of the pathophysiology and clinical outcomes of COVID-19 in pediatric patients with autoimmune disorders due to scattered reports and inadequate evidence.

WHAT IS NEW

• Generally, children with autoimmune disorders have more unfavorable outcomes than healthy children; yet, the severity is not extreme, and is highly dependent on their autoimmune disease type and severity, as well as the medication they are taking.

The Impact of COVID-19 Infection on Miscellaneous Inflammatory Disorders of the Gastrointestinal Tract

The novel coronavirus pandemic of COVID-19 has emerged as a highly significant recent threat to global health with about 600,000,000 known infections and more than 6,450,000 deaths worldwide since its emergence in late 2019. COVID-19 symptoms are predominantly respiratory, with mortality largely related to pulmonary manifestations, but the virus also potentially infects all parts of the gastrointestinal tract with related symptoms and manifestations that affect patient treatment and outcome. COVID-19 can directly infect the gastrointestinal tract because of the presence of widespread angiotensin-converting enzyme 2 receptors in the stomach and small intestine that can cause local COVID-19 infection and associated inflammation. This work reviews the pathopysiology, clinical manifestations, workup, and treatment of miscellaneous inflammatory disorders of the gastrointestinal tract other than inflammatory bowel disease.

Prevalence and clinical outcomes of COVID-19 in patients with pre-existing celiac disease: A systematic review and meta-analysis

There is a scarcity of scientific evidence addressing the outcomes of COVID-19 in celiac disease (CD) patients. This systematic review and meta-analysis aimed to evaluate the correlation between pre-existing CD and COVID-19. A rigorous literature search was conducted using multiple databases. All eligible observational studies were included from around the globe. The random effect model calculated the pooled prevalence and associated 95% confidence intervals (CI). Mantel-Haenszel odds ratios were produced to report the overall effect size using random effect models for severity and mortality outcomes. Funnel plots, Egger regression tests, and Begg-Mazumdar's rank correlation test were used to appraise publication bias. Data from 11 articles consisting of 44,378 CD patients were obtained. Overall pooled random-effects estimate of SARS-CoV-2 infection in CD patients was 4.25% (95% CI, I²  = 98%). Our findings also indicated that pre-existing CD was not associated with an increased risk of hospitalisation with COVID-19 illness (OR = 1.04, 95% CI 0.87-1.24, I²  = 0%) and mortality due to illness (OR = 0.92, 95% CI 0.56-1.5, I²  = 45%) compared with patients without pre-existing CD. No significant publication bias was evident in the meta-analysis. The preliminary data from our analysis suggest that SARS-CoV-2 infection in patients with pre-existing CD is not associated with an increased risk of hospitalisation or mortality. Additional studies are required to overcome the restrictions of the limited data available at present.

Celiac Disease and Targeting the Molecular Mechanisms of Autoimmunity in COVID Pandemic

Celiac disease (CD) comprises over 1% of the world’s population and is a chronic multisystem immune-mediated condition manifested by digestive and/or extradigestive symptoms caused by food intake of gluten. This review looked at the risk of children diagnosed with CD developing SARS-CoV-2 infection and possible severe forms of COVID-19. A better understanding of the interaction and effects of SARS-CoV-2 infection in CD is very important, as is the role of environmental and genetic factors, but especially the molecular mechanisms involved in modulating intestinal permeability with impact on autoimmunity. CD inspired the testing of a zonulin antagonist for the fulminant form of multisystem inflammatory syndrome in children (MIS-C) and paved the way for the discovery of new molecules to regulate the small intestine barrier function and immune responses. Original published works on COVID-19 and CD, new data and points of view have been analyzed because this dangerous virus SARS-CoV-2 is still here and yet influencing our lives. Medical science continues to focus on all uncertainties triggered by SARS-CoV-2 infection and its consequences, including in CD. Although the COVID-19 pandemic seems to be gradually extinguishing, there is a wealth of information and knowledge gained over the last two years and important life lessons to analyze, as well as relevant conclusions to be drawn to deal with future pandemics. Zonulin is being studied extensively in immunoengineering as an adjuvant to improving the absorption of new drugs and oral vaccines.

Celiac Disease and Targeting the Molecular Mechanisms of Autoimmunity in COVID Pandemic

Celiac disease (CD) comprises over 1% of the world's population and is a chronic multisystem immune-mediated condition manifested by digestive and/or extradigestive symptoms caused by food intake of gluten. This review looked at the risk of children diagnosed with CD developing SARS-CoV-2 infection and possible severe forms of COVID-19. A better understanding of the interaction and effects of SARS-CoV-2 infection in CD is very important, as is the role of environmental and genetic factors, but especially the molecular mechanisms involved in modulating intestinal permeability with impact on autoimmunity. CD inspired the testing of a zonulin antagonist for the fulminant form of multisystem inflammatory syndrome in children (MIS-C) and paved the way for the discovery of new molecules to regulate the small intestine barrier function and immune responses. Original published works on COVID-19 and CD, new data and points of view have been analyzed because this dangerous virus SARS-CoV-2 is still here and yet influencing our lives. Medical science continues to focus on all uncertainties triggered by SARS-CoV-2 infection and its consequences, including in CD. Although the COVID-19 pandemic seems to be gradually extinguishing, there is a wealth of information and knowledge gained over the last two years and important life lessons to analyze, as well as relevant conclusions to be drawn to deal with future pandemics. Zonulin is being studied extensively in immunoengineering as an adjuvant to improving the absorption of new drugs and oral vaccines.

New-onset celiac disease in children during COVID-19 pandemic

Aim

We aimed to analyse the influence of the COVID‐19 pandemic on the frequency and clinical presentation of celiac disease.

Methods

The study included the patients with celiac disease since January 2008. They were divided into 2 groups (diagnosed in pre‐pandemic [January 2008 and February 2020] [n = 148] and in pandemic period [March 2020 and June 2021] [n = 47]). Clinical and histological findings were compared between groups. Additionally, data about severe acute respiratory syndrome coronavirus 2 infection were obtained in subgroup patients (n = 22) with celiac disease diagnosed during pandemic period.

Results

The number of patients per year (12.1–37.6) and the percentage of patients who were diagnosed with celiac disease/total endoscopy were increased during the pandemic period (2.2% vs. 10%, p < 0.00001). The association of celiac disease with type 1 diabetes mellitus was significantly high in pandemic period (4% vs. 17%, p = 0.002). Frequency of moderate‐severe mucosal lesions was low in pandemic period (42.4% vs. 81.7%, p = 0.0001). Clinical and laboratory markers for the past severe acute respiratory syndrome coronavirus 2 infection were found in 36.3% of patients diagnosed during the pandemic period.

Conclusion

It seems that the frequency of celiac disease and its association with type 1 diabetes mellitus is increased during the COVID‐19 pandemic in children.