Immunological diagnosis of childhood coeliac disease: comparison between antigliadin, antireticulin and antiendomysial antibodies.

The immunological markers proposed to supplement intestinal biopsy for the diagnosis of coeliac disease are antigliadin, antireticulin and antiendomysial antibodies. These antibodies have been studied separately or compared as pairs, but no prospective comparison of all three antibodies in childhood coeliac disease exists. Thirty-four confirmed coeliacs were compared with nine non-coeliacs with pathological small intestines, and 32 children with a normal intestinal histology. Sera were examined for IgG- and IgA-antigliadin antibodies (AGA) by ELISA, and for IgA-antireticulin antibodies (ARA) and IgA endomysial antibodies (EMA) by indirect immunofluorescence. In active coeliac disease, IgA-EMA was the most sensitive (97%), while IgA-AGA the least sensitive antibody (52%). The specificity of IgA-AGA, IgG-AGA, IgA-ARA, IgA-EMA was 95%, 92%, 100% and 98%, respectively. Positive predicted values of ARA and EMA were comparable (97-100%), while EMA had the highest negative predicted value (98%). Compared with IgG-AGA, IgA-EMA titres better reflected variations in dietary gluten, and correlated best with intestinal pathology. Compared with AGA and ARA sensitivity, specificity and predictive values, EMA is the most reliable serological marker for the diagnosis of coeliac disease. It reflects dietary changes in gluten and correlates best with intestinal histopathology. Therefore, it should be considered the best of the three serological tests available for childhood coeliac disease.