Correlation of Tissue Transglutaminase Antibody Level with Histopathological Changes in Duodenum of Paediatric Patients with Celiac Disease

Background: Celiac disease causes intestinal damage triggered by gluten in genetically predisposed children. Anti-tissue transglutaminase (anti-tTG) antibodies aid diagnosis, but their link to mucosal damage severity needs clarification. Objective: To correlate anti-tTG antibody titers with the severity of duodenal mucosal damage, as assessed by Marsh grading, in pediatric patients with celiac disease. Methods: This cross-sectional study included 40 pediatric patients (aged 1–18 years) with confirmed CD at a tertiary care center in Haryana, India. Data on clinical features, anti-tTG antibody levels, and duodenal biopsy findings (Marsh classification) were collected. Anti-tTG was measured by ELISA, with >18 U/mL considered positive. Statistical analysis involved ANOVA, Chi-square tests, and ROC curve analysis to determine the optimal anti-tTG cut-off for predicting severe mucosal damage. Results: Marsh grade III lesions were observed in 82.5% of patients, with 47.5% showing complete villous atrophy (IIIc). Anti-tTG titers varied significantly across Marsh grades (p < 0.001). An anti-tTG cut-off of 84 U/mL predicted Marsh grade III with 84.8% sensitivity, 85.7% specificity, and 85.0% overall diagnostic accuracy. Patients with titers ≥84 U/mL were 33.6 times more likely to have severe mucosal damage (p = 0.003). Conclusion: High anti-tTG levels strongly indicate severe intestinal injury, supporting their use in diagnosis and potentially reducing biopsy need in children.