Insights in the laboratory diagnosis of celiac disease.

The present report focuses on the diagnosis of celiac disease and its pathogenesis, which depends on a genetic predisposition (HLA DQ2 or DQ8 haplotypes), gluten ingestion and T cell activation, type II transglutaminase (TG2), the autoantigen recognized by the antiendomysial antibody playing a key role. IgA class antibody anti-environmental (gliadin) and endogenous (TG2) antigens are present in the sera of patients with celiac disease. The anti-TG2 antibody has the best available diagnostic accuracy, especially when measured employing second generation ELISA tests, which use the human TG2 antigen, or immunochemiluminescent assay, which is highly sensitive. A diagnosis of celiac disease must always be confirmed by the histological evaluation of multiple duodenal mucosa specimens, and serology is recommended for follow-up controls.