Anti-transglutaminase autoantibodies in saliva. Usefulness of the radioimmunological test in coeliac children and adolescents: A multicenter study

Background: In a large series of six to eight years primary school-children, radioimmunological assay (RIA) for IgA anti-transglutaminase (TG2) in saliva has been demonstrated to be a sensitive screening method for coeliac disease (CD) (Nenna R et al., JPGN 2013).Objective: Our aims were to evaluate the sensibility and specificity of IgA TG2 RIA on saliva in children and adolescents at CD diagnosis.Patients and methods: Over the period November 2011–May 2013, 85 CD children and adolescents (22 males, age range 1–18 years, median 7.92 years) on a gluten-containing diet, positive to serum IgA TG2RIA and/or ELISA, underwent a saliva collection to assay IgA TG2 by RIA. Moreover, 35 gastroenterological controls (GC) (18 males, age range 4–15 years, median 10 years) were enrolled.Results: 68 out of 85 biopsy-proved CD children and adolescents (80.0%) showed high IgA TG2 RIA index in saliva. Particularly, six out of 10 children aged below 5 years (60.0%), 39 out of 41 aged from 5 to 9 years (95.1%) and 26 out of 34 children and adolescents aged more than 9 years (76.5%) showed high TG2 Ab-Index. All GC were IgA TG2 negative.Conclusions: The results of this preliminary report confirm a good sensitivity of the salivary test in primary school-children aged 5–9 years, while in younger, as well as older children and adolescents, blood tests show higher performance. In the small series the specificity of the test was good both in children and in adolescents. Background: In a large series of six to eight years primary school-children, radioimmunological assay (RIA) for IgA anti-transglutaminase (TG2) in saliva has been demonstrated to be a sensitive screening method for coeliac disease (CD) (Nenna R et al., JPGN 2013). Objective: Our aims were to evaluate the sensibility and specificity of IgA TG2 RIA on saliva in children and adolescents at CD diagnosis. Patients and methods: Over the period November 2011–May 2013, 85 CD children and adolescents (22 males, age range 1–18 years, median 7.92 years) on a gluten-containing diet, positive to serum IgA TG2RIA and/or ELISA, underwent a saliva collection to assay IgA TG2 by RIA. Moreover, 35 gastroenterological controls (GC) (18 males, age range 4–15 years, median 10 years) were enrolled. Results: 68 out of 85 biopsy-proved CD children and adolescents (80.0%) showed high IgA TG2 RIA index in saliva. Particularly, six out of 10 children aged below 5 years (60.0%), 39 out of 41 aged from 5 to 9 years (95.1%) and 26 out of 34 children and adolescents aged more than 9 years (76.5%) showed high TG2 Ab-Index. All GC were IgA TG2 negative. Conclusions: The results of this preliminary report confirm a good sensitivity of the salivary test in primary school-children aged 5–9 years, while in younger, as well as older children and adolescents, blood tests show higher performance. In the small series the specificity of the test was good both in children and in adolescents.