Antibody reactivity against human and guinea pig tissue transglutaminase in children with celiac disease

Background: Highly discriminatory markers for celiac disease are needed to identify children with early mucosal lesions. The purposes of this study we re to evaluate the clinical potential of circulating anti-tissue transgluta minase (tTG) immunoglobulin (Ig)A antibodies in the diagnosis of childhood celiac disease and to investigate the extent of autoreactivity of these ant ibodies. Methods: Included in this retrospective study were samples from 22 children with biopsy-verified celiac disease, 23 control subjects with disease, and 22 healthy control subjects without any known gastrointestinal or inflamma tory disorders. An enzyme-linked immunosorbent assay (ELISA) was used to me asure the serum levels of IgA antibodies specific for human and guinea pig tTGs. All samples were also analyzed for antibodies to gliadin and endomysi um (EMA). Results: The concentrations of IgA specific for human and guinea pig tTGs c on-elated with the small intestinal villous structure and the serum levels of IgA EMA. The tTG ELISAs exhibited a high specificity and sensitivity for detection of untreated celiac disease. The human erythrocyte IgA tTG ELISA had the highest sensitivity (100%) and a specificity of 98%. The IgA EMA m ethod had a sensitivity of 95% and the highest specificity (100%) of all te sts. Conclusions: Our results provide additional support to the concept that ant i-tTG IgA antibodies can be used as a highly discriminatory serologic marke r for celiac disease and that measurements of these autoreactive antibodies may in the future be used as an alternative to the EMA test.