Comparison of ELISA for tissue transglutaminase autoantibodies with antiendomysium antibodies in pediatric and adult patients with celiac disease

Background: Tissue transglutaminase (t-TG) is the main autoantigen recogniz ed by the endomysium antibodies (EMA) observed in patients with celiac dise ase (CD). The aim of the study was to assess an ELISA method for t-TG antib odies (t-TGA) with respect to EMA IF assay in pediatric and adult patients. Methods: t-TGA were analyzed by ELISA in 220 sera samples: 82 patients with biopsy-proven untreated CD (23 adults and 59 children), 14 CD children on gluten-free diet, 18 asymptomatic relatives of CD patients, and 106 age-mat ched control patients with gluten-unrelated gastrointestinal diseases (58 a dults and 48 children). Serum IgA EMA were tested on umbilical cord section s in all patients. Results: The great majority (92.7%) of untreated CD patients (both adults a nd children) were t-TGA positive (values ranging from 20.1 to > 300 AU). No ne of the child control patients and only two out of 58 (3.4%) of the adult s with unrelated gastrointestinal diseases had serum t-TGA positivity; two out of 18 first-degree relatives with biopsy-proved silent CD were t-TGA la s well as EMA) positive. Finally, two out of 14 CD children, assuming a glu ten-free diet, had serum t-TGA las well as EMA). A highly significant corre lation (P <0.001) was observed beween t-TGA concentrations and EMA. t-TGA s howed a sensitivity of 87% and 95%, a specificity of 97% and 100% for adult s and children, respectively. Conclusions: The method is highly sensitive and specific in the diagnosis o f CD and is promising as a tool for routine diagnostic use and population s creening, especially in children.