Immunoglobulin A antigliadin antibodies in jejunal juice: markers of severe intestinal damage in coeliac children.

Antibodies to gliadin (AGA), detected in jejunal juice by immunofluorescence and enzyme-linked immunosorbent assay, have been found in 13 of 15 (87%) children with untreated coeliac disease. Jejunal AGA were also positive in 6 of the 9 (67%) coeliac children on gluten challenge, while they were consistently negative in coeliac children on a gluten-free diet and in controls. Jejunal AGA were always of immunoglobulin A (IgA) class, associated with IgM in some cases. Moreover, the presence of IgA AGA in jejunal juice was strictly related to the severity of intestinal damage. These data suggest that IgA AGA, detected in jejunal juice are synthesized from gut mucosa and are markers of its abnormal function. Like AGA, antibodies to milk and egg proteins were only found in jejunal juice of coeliac patients with flat intestinal mucosa, but their prevalence was significantly lower than that of AGA.