While specific blood tests are used to detect the presence of celiac disease, new research indicates that changes in immune function or gastrointestinal health could begin well before tTG blood tests turn up positive.

In a study of 100 children, 50 cases of celiac disease matched against 50 controls, researchers analyzed the presence of IgG antibodies to wheat storage globulin Glo-3A in blood samples taken from birth up to the point of positive tTG in children with celiac disease.

Compared to controls, children with celiac disease had higher levels of Glo-3A at the age when they first tested positive for tTG antibodies (mean age: 4.9 years). However, Glo-3A levels peaked an average 2 years before tTG-positivity; Glo-3A was highest at the mean 2.9 years. At this peak, children with celiac disease still showed higher levels of Glo-3A antibodies than controls. In fact, the levels were higher than those of controls throughout all the years analyzed, according to the study.

Researchers concluded that children with celiac disease have higher cases of elevated Glo-3A levels, even before the condition is detected by tTG testing.