The Usefulness of IgA/IgG DGP/tTG Screen Assay for Celiac Disease Detection among Symptomatic and at Risk Young Children

Background: It has been postulated that IgA anti tissue-transglutaminase (tTG) and anti-endomisium (EMA) antibodies can be false negative in young children.ESPGHAN recommended for seronegative children younger than 2 years old with clinical suspicion of celiac disease to perform duodenal biopsies. Recent studies sugested that the combined assay for IgA/IgG deamidated gliadin peptides (DGP) and tTG can detect celiac disease among seronegative young children. Aim: To assess if the new combined assay with synthetic gliadin derived peptides IgA/IgG-DGP/tTG is useful to detect celiac disease in IgA tTG or EMA seronegative children younger than 2 years old. Methods: The authors screened a lot of children aged 6 months to 2 years old that associated characteristic symptoms/risk factors for gluten enteropathy. 368 children were tested for IgAtTG, EMA and IgA/IgG-tTG/DGP combined assay. All children had normal total IgA concentration and were consuming gluten at the time of enrolment. Children with at least one positive serologic test underwent intestinal biopsy, including seronegative infants, DQ2/DQ8 positive, with clinical suspicion of celiac disease that underwent the 2 biopsies protocol. Results: Celiac disease was diagnosed in 22 children based on histology. 19 children were positive for IgA tTG, 20 were positive for EMA and 21 tested positive for IgA/IgG-DGP/tTG. IgA tTG sensitivity was 86.3%, IgA EMA sensitivity was 91% and IgA/IgG-DGP/tTG sensitivity was 95.4% (p=0.002). Conclusions: The sensitivity of IgA/IgG DGP/tTG assay was significantly higher than that of IgAtTG in celiac patients younger than 2 years old.The better performance of this new combined test can avoid repeated intestinal biopsies in young children with high clinical suspicion of celiac disease but negative tTG/ EMA serology.