Coeliac disease (CD) is an immune-mediated enteropathy triggered by dietary gluten in genetically susceptible individuals and is more common in children with type 1 diabetes (T1D) and their relatives than in the general population. The Environmental Determinants of Islet Autoimmunity (ENDIA) Study is a prospective Australian pregnancy-to-childhood cohort of children with a first-degree relative with T1D. We describe CD autoimmunity (CDA) and CD in ENDIA children, including serology, diagnostic pathways, HLA genotypes, and overlap with islet autoimmunity (IA).
ENDIA enrolled unborn children or infants younger than 6 months with a first-degree relative with T1D. Participants were followed from pregnancy or infancy until 10 years, T1D diagnosis, or withdrawal. CDA was defined as at least two positive tissue transglutaminase antibody results collected at least 3 months apart. CD was defined as biopsy-proven disease (Marsh score ≥2) or fulfilment of ESPGHAN no-biopsy criteria. Children with persistent CDA and negative biopsy, with ongoing gluten consumption were classified as potential CD. Descriptive analyses were used.
The cohort comprised 1,473 children born between 2012-2020 (median age 8.9 years; range 6.1-13.7). Of the 1,270 children who underwent coeliac serology testing (86.2% of cohort), 205 (13.9%) had at least one positive coeliac serology result (tissue transglutaminase and/or deamidated gliadin peptide antibodies) or CD. CD was diagnosed in 70 children, including 55 biopsy-confirmed cases and 15 meeting ESPGHAN criteria. A further 29 children met the definition for CDA and 3 for potential CD, giving 102 children with CD, CDA, or potential CD. Preliminary HLA analyses showed enrichment of HLA-DQ2-associated DR3 haplotypes among children with CD (80%). Eighteen children had both T1D/IA and CD/CDA.
ENDIA provides a unique resource for studying the development of CDA and CD in children at increased autoimmune risk and will support investigation of early-life determinants of CD and its overlap with IA and T1D.