Irritable bowel syndrome (IBS) is a common
functional gastrointestinal disorder. Due to the possible overlap of IBS clinical symptoms with
gluten-related diseases,
food allergies, and autoimmune
gastritis (AIG), the aim of this study was to present the frequency of anti-
tissue transglutaminase 2 (TTG2)
autoantibodies, anti-deamidated
gluten peptide (DGP)
antibodies, specific
immunoglobulin E antibodies (sIgE) to selected food
allergens, and anti-
intrinsic factor (IF)
autoantibodies in adult patients with
diarrhea-predominant IBS (IBS-D). The study involved 244 patients (170 women) aged 18-75 years. The
antibodies were measured with the use of multiparametric immunoassays. Elevated antibody concentrations, irrespective of the class of tested antibody, occurred in 44 patients (17.6%), including 11 patients (4.5%) with positive DGP
antibodies, four patients (1.6%) with TTG2
autoantibodies, six patients (2.5%) with IF
autoantibodies, and 31 patients (12.7%) with sIgE to food
allergens. Sensitization to
gluten, proteins from cow's milk, and
bovine serum albumin was found in 2.1%, 5.3%, and 9.0% of patients, respectively. Our study showed a high percentage of positive results for the tested
antibodies in the IBD-D patients, which indicates the need to perform serological tests for CD,
food allergies, and AIG in this group of patients.