Diagnostic Significance of Positive EmA Antibodies in the Duodenal Culture Medium of Not-Celiac Wheat Sensitivity (NCWS)

The most frequent diseases caused by wheat ingestion are T cell-mediated disorders, i.e. celiac disease and immunoglobulin E (IgE)-mediated allergic reactions. However, besides celiac disease and wheat allergy, there are cases of gluten reactions in which neither autoimmune nor IgE-mediated allergic mechanisms are involved. These are generally defined as GS or Not-celiac wheat sensitivity (NCWS). Typically, NCWS diagnosis is made by exclusion, and an elimination diet and an "open challenge" (i.e., the monitored reintroduction of gluten-containing foods) are most often used to evaluate whether health improves or worsen with the elimination or reintroduction of gluten in the diet, respectively. In some circumstances, it is very difficult to distinguish between NCWS and celiac disease. The presence of positive celiac disease specific serum antibodies (anti-tissue transglutaminase (anti-tTG), and anti-endomysium (EmAs) antibodies) is of paramount importance to pose the diagnosis. However, it is well known that the frequency of a positive serology is dependent by the severity of the intestinal damage. Consequently, patients with less severe histology damage (Marsh 1) can have negative serum antibodies. Previous studies had demonstrated that EmAs are produced by the intestinal lymphocytes and previous data from our group showed that EmAs assay in the culture medium of the intestinal biopsies has higher diagnostic accuracy than serum EmAs in diagnosis. Therefore, the aims of our study are to evaluate the clinical-serologic-histology course of NCWS patients, showing positive EmAs assay in the culture medium of the duodenal biopsies at the time of the first evaluation, and the adherence to a gluten-free diet in NCWS patients after a previous full evaluation and a NCWS diagnosis based on double-blinded placebo-controlled (DBPC) challenge.