Association of Anti-tissue Transglutaminase Antibody Titers and Duodenal Biopsy Findings in Pediatric Patients of Celiac Disease

Aims & Objectives To ascertain the association of serum anti-tissue transglutaminase (anti-tTG) antibody titers with the severity of duodenal mucosal damage on histology and to predict a possible cut-off value of anti-tTG antibody titers for the diagnosis of Celiac disease. Marsh grading greater than two in conjunction with clinical assessment, which may help avert an invasive endoscopic procedure, especially in medically unfit children. Materials & Methods A retrospective study was designed wherein demographic and laboratory data of children aged less than 12 years with raised anti-tTG antibody titers with available histopathology of duodenal biopsies were extracted from the hospital medical records and reviewed. Results A total of 134 children were included in the study, which showed female preponderance. Histopathological changes, characteristic of Celiac disease, were observed in 116 cases; seven among the rest showed evidence of Giardiasis, and 13 could be considered potential Celiac. Of the 116 patients, 1.7% belonged to Marsh grade I, 5.2% grade II and 8.6%, 26.7%, and 57.7% to grade IIIA, IIIB, and IIIC, respectively. A significant association was found between anti-tTG antibody titers and Marsh grading. The cut-off value of anti-tTG antibody titer levels for diagnosing Celiac disease using receiver operating characteristics (ROC) curve in predicting Marsh greater than two at histology was observed to be 84.6 U/ml with sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 91.7%, 68.4%, 94.2%, and 59%, respectively. Conclusion An anti-tTG antibody titer greater than 10 times the upper limit of normal (>= 84 U/ml) is significantly associated with Marsh grade greater than two. Standard stool microscopy may be used as a simple tool in the workup of all children with raised anti-tTG antibody levels to rule out Giardiasis to avert unnecessary endoscopic evaluation for Celiac disease in such cases.