Uselessness of anti-actin antibody in celiac disease screening

BackgroundSerum anti-actin IgA antibodies (AAA) were identified in patients with celiac disease (CD), and a close correlation emerged between the presence of AAA and mucosa damage, but test for AAA found in celiacs have a wide range of sensitivity and specificity values.AimTo compare 1) the sensitivity and specificity of untreated, calcium-chelated and heated sera from 102 celiacs, 52 sick patients and 103 healthy controls in the determination of AAA, and 2) the reliability of AAA with anti-transglutaminase antibodies (anti-tTG) in diagnosing celiac disease and in predicting intestinal damage. The intestinal derived AAA was isolated by using the phage-display library technique.ResultsTreated sera was significantly more sensitive than untreated (p = 0.0001), and showed a significant correlation between AAA and the three degrees (3a, 3b, 3c) of intestinal damage (p = 0.01). Sensitivity and specificity values of anti-tTG assay were higher than the AAA assay, and anti-tTG serum-concentration was only significantly correlated with more severe (3b and 3c) intestinal damage degrees. AAA isolated by phage display showed similar results of serum AAA in immunofluorescence assay.ConclusionsNotwithstanding correlation between AAA and celiac disease, AAA assay, also after treatments, has little to offer in screening for CD compared to the well-established anti-transglutaminase assay.