Is TCRγ Clonality Assay Useful to Detect Early Celiac Disease?

Abstract

Although histology is considered the gold standard for the diagnosis of celiac disease, the early stages (latent or potential) of this disease are difficult to diagnose, because of the negativity of laboratory tests and the lack of villous atrophy. Thus, markers of early disease are needed. We investigated the possibility to detect latent or potential celiac disease by means of TCRgamma clonality assay in intraepithelial T cells in patients with suspected disease, negative laboratory tests, and an increased number of intraepithelial lymphocytes. Duodenal biopsies were obtained from 35 patients with nonspecific duodenitis (controls), 13 latent or potential celiac disease subjects, 28 well-defined celiac patients, and 8 celiac patients in gluten-free diet. Histologic and immunohistochemical quantification of intraepithelial lymphocytes, as well as TCRgamma clonality assay, were carried out in all subjects by means of standard techniques. Intraepithelial lymphocytes and TCRgamma clonality were significantly increased in potential and defined celiac patients with respect to the controls, even though the increase in TCRgamma clonality was lesser with respect to that of intraepithelial lymphocytes. No significant differences were found concerning this variable between the potential and defined celiac subjects. TCRgamma clonality does not represent a marker of early disease. However, it might be useful to help in distinguishing celiac disease from other causes of nonspecific duodenitis.