Introduction: Celiac disease (CD) remains one of the few autoimmune disorders in which diagnostic screening still relies on a single serological biomarker, anti-tissue transglutaminase (tTG) antibodies. We hypothesized that incorporating neo-epitope biomarkers into a multiplex assay would improve diagnostic performance and support biopsy-sparing diagnosis in pediatric celiac disease.
Aim: To determine whether multiplex neo-epitope serology outperforms conventional anti-tTG testing and supports biopsy-sparing diagnosis in pediatric CD.
Methods: A total of 100 children (mean age 10.7 ± 4.5 years), including 71 patients with CD diagnosed according to ESPGHAN criteria and 29 non-celiac controls, were analyzed using the AESKUBLOTS® Gluten Related Disorders (GRD) multiparametric immunoblot. IgA antibodies against conventional celiac disease antigens, neo-epitopes (tTG-neo and mTG-neo), and total IgA were measured. Diagnostic performance was assessed by ROC analysis and correlation with EMA endpoint titers.
Results: Among all biomarkers, tTG-neo IgA demonstrated the highest diagnostic accuracy, with 91.4% sensitivity, 100% specificity, and an AUC of 0.957, outperforming conventional anti-tTG IgA (79.3% sensitivity, 97.6% specificity, AUC 0.885). mTG-neo IgA achieved 75.9% sensitivity, 100% specificity, and an AUC of 0.879. Both neo-epitope antibodies showed a strong correlation with EMA endpoint titers (r² > 0.75, p < 0.001). Simultaneous measurement of total IgA identified IgA deficiency in 7% of patients.
Discussion: Multiplex assessment of conventional and neo-epitope biomarkers improved diagnostic performance while simultaneously identifying IgA deficiency. The strong association with EMA titers supports their role in strengthening serology-based diagnosis.
Conclusion: Our findings support a shift from single-marker testing toward multiparametric serology in pediatric CD. Incorporating neo-epitope biomarkers improves diagnostic accuracy, enables simultaneous identification of IgA deficiency, and may strengthen biopsy-sparing diagnostic strategies in accordance with current ESPGHAN recommendations. As in most autoimmune diseases, assessing multiple disease-relevant antibody specificities rather than relying on a single biomarker may represent the next step in the evolution ofCD serology.