Summary

Introduction: Celiac disease (CD) is an autoimmune pathology, which develops at any age in genetically susceptible people, and whose main target organ is the small intestine. The diversity in the forms of presentation currently known implies a permanent challenge for the laboratory, which must offer new, increasingly sensitive and specific techniques, to efficiently detect specific autoantibodies for the diagnosis and follow-up of these patients. Our objective was to evaluate the sensitivity and specificity of a new antigen for the detection of anti-transglutaminase antibodies composed of tissue transglutaminase covalently linked to deamidated gliadin peptides (neo-epitope) in patients with suspected CD, with duodenal biopsy as the gold standard. As a secondary objective, we set out to evaluate the sensitivity and specificity of the conventional antigen, recombinant human transglutaminase, for the same study group. Methodology: A prospective study was carried out, analyzing samples from patients with suspected CD or being monitored for said disease, in which anti-transglutaminase antibodies with neo-epitope antigen and with recombinant human transglutaminase antigen were studied. Sensitivity, specificity, PPV, NPV, and Kappa coefficient of concordance were determined. Results: 56 samples were processed, included in a period of 5 months. The sensitivity (100%) and specificity (92.3%) obtained with the neo-epitope technique, in relation to the biopsy (gold standard), was higher than with the recombinant human transglutaminase technique (88.3% and 78.9% respectively). . The neo-epitope technique provided fewer results in the "zone of indeterminacy." Conclusions: Our results agree with other authors, since neo-epitope detects with greater sensitivity and specificity those patients with different presentation situations and transgressors of the gluten-free diet, who may present negative or weakly positive serology with recombinant human transglutamiasa. The new neo-epitope technique would constitute a better tool for diagnostic research and follow-up in patients with CD.