Background of Different Phenotypes of Coeliac Disease

Study Overview
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Brief Summary
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The main purpose of this study is to investigate genetic, serological, immunological and microbiata diversities between different coeliac disease phenotypes and to discover applicable prognostic markers for specific phenotypes.

Detailed Description
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The recognition of clinical heterogeneity has expanded the understanding of coeliac disease, but the factors contributing to this diversity remain unclear. Moreover, since coeliac disease is highly heterogeneous, there is a need for more individualized follow-up and support and implementation of more personalized follow-up guidelines. In this study coeliac disease and dermatitis herpetiformis patients and healthy controls will be recruited. Genetic, clinical, immunological, micobiata and novel biomedical markers are compared between coeliac disease phenotypes and also controls and their prognostic value is assessed.

Official Title
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Genetic and Biological Background and Follow-up of Different Phenotypes of Coeliac Disease

Conditions
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Celiac Disease, Dermatitis Herpetiformis

Intervention / Treatment
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* Genetic: Genetic predisposition


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Cohorts 1 and 2: coeliac disease or dermatitis herpetiformis diagnosis Cohort 3: friend or non-related family member of coeliac disease or dermatitis herpetiformis patient Exclusion Criteria: Cohorts 1-3: Age <18 years Cohorts 1 and 2: coeliac disease or dermatitis herpetiformis diagnosis not confirmed Cohort 3: coeliac disease or dermatitis herpetiformis diagnosis

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Coeliac disease patients<br>Adult (18 years or over) patients with previous coeliac disease or dermatitis herpetiformis diagnosis | Genetic: Genetic predisposition<br>* Assessment of genetic predisposition to various celiac disease phenotypes. No intervention.<br>|
| Healthy controls<br>500 adult (18 years or over) friends or non-related family members of coeliac disease or dermatitis herpetiformis patients participating in the study, no previous coeliac disease or dermatitis herpetiformis diagnosis. In addition 1000 controls will be included from Biobank | Genetic: Genetic predisposition<br>* Assessment of genetic predisposition to various celiac disease phenotypes. No intervention.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Non-HLA variant association | phenotype specific non-HLA variants | baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| serum transglutaminase antibodies | Levels of serum antibodies against transglutaminase | baseline | 
| microbiata | skin and intestinal microbiata findings | baseline | 
| quality of life measure | PGWB questionnaire (22-items with values 1-6, total score range 22-132, a higher score indicating better quality of life) | baseline | 
| gastrointestinal symptoms | GSRS-questionnaire (15 items with values 1-7, total score 1-7 as a mean value of all scores, higher score indicating more severe symptoms) | baseline | 
| dietary adherence | strictness of gluten-free diet (GIP-test) | baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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coeliac disease, dermatitis herpetiformis, gluten-free diet, transglutaminase, microbiata