Clinical application of immunological markers as monitoring tests in celiac disease

The aim of this study was to investigate anti-gliadin (IgA-AGA and IgG-AGA), endomysial (IgA-EmA), and anti-reticulin (Ig-ARA) antibodies for monitoring celiac disease (CD) patients while on gluten-free and gluten-containing diets. Sera from 30 confirmed CD patients (13 boys, 17 girls), 1-24 years old, were examined for antibodies using ELISA (AGA) and Immunofluorescence (EmA, ARA) at 1, 3, 6, 9, and 12 months following institution of gluten-free diet and also at 3 and 6 months after challenge with gluten. One month following the exclusion of gluten from the diet, most antibodies are still positive. Twenty-three to 43% of antibodies remained positive by the end of the third month. At 6 and 9 months, 17% and 10% were positive, respectively. At 12 months no positive antibodies were detected. After gluten challenge, positive IgA-AGA and IgA-EmA titers were already demonstrated at 3 months (90% and 86%, respectively), while Ig-ARA titers showed a slow increase. Finally IgG-AGA responded with a slow decrease of titers to gluten-free diet levels and a fast increase upon provocation. The morphology of the intestine at diagnosis and during the periods of gluten-free diet and gluten challenge corresponds with the antibody titers. On the basis of these results, immunological markers may be applied to follow-up CD patients. IgA-AGA and IgA-EMA appear to be the most sensitive to dietary changes in gluten and correlate best with intestinal mucosal morphology.