Serological Update on Celiac Disease Diagnostics in Adults

Celiac disease (CD) is an inflammatory disorder of the small intestines which serological diagnosis has come to the forefront with the development of the immunological testing. We aimed to explore the performance characteristics of a panel of serological tests in patients with CD. We assessed the serum levels of anti-tissue transglutaminase (anti-tTG), anti-deamidated gliadin peptides (anti-DGP), anti-actin (AAA), anti-gliadin antibodies (AGA) and cytokine IL-17A by performing ELISA; and anti-tTG, AGA and anti-Saccharomyces cerevisiae antibodies (ASCA) by immunoblot in 35 newly diagnosed adult patients with biopsy-proven CD and 25 age- and sex-matched healthy persons. The average serum levels of anti-tTG, anti-DGP, AGA, AAA, and ASCA were at significantly higher levels in patients with CD compared to healthy persons (p<0.001). We also observed that the serum level of IL-17A was about 70 times higher in CD patients than in the healthy persons (p=0.027). Anti-DGP antibodies showed highest diagnostic sensitivity (100%), followed by AGA and anti-tTG antibodies within the CD group. ROC curve analysis revealed the excellent performance of anti-DGP, anti-tTG, and AGA in the diagnosis of CD patients (AUC 1.000, 0.994, 0.992 respectively, p<0.001). Although the diagnosis of CD relays on biopsy, immunological serological testing could be employed with advantages in diagnosis and monitoring of CD patients.