New developments in serodiagnosis of childhood celiac disease: assay of antibodies against deamidated gliadin.

Antibodies to deamidated gliadin present a new tool in the diagnosis of celiac disease (CD). In children, the ELISA for the determination of IgG antibodies to (deamidated) gliadin-analogous fusion peptides (GAF3X) has a superior performance compared to the ELISA for the determination of antibodies against native gliadin and is comparable to assays for IgA antibodies against tissue transglutaminase (IgA-anti-tTG). The combined investigation of IgG antibodies to GAF3X (IgG-anti-GAF3X) and IgA-anti-tTG significantly increases the fraction of children definitely identified as either CD or non-CD patients. The new IgG-anti-GAF3X ELISA was also able to detect CD in three cases of IgA deficiency and in two cases of latent CD and was also useful in the diagnosis of children younger than 2 years of age.