Coeliac disease: Antibodies and adherence to diet.

MOTTA, ESTELA; CHISARI, ANDREA; GARCÍA, VIRGINA; GADEA, HORACIO; DOVAO, ROCÍO; DI MAURO, PAULA; ZIALLORENZO, PAULA

Buenos Aires

Congreso; LXIII Annual Meeting of the Argentinean Society for Immunology, IV Meeting of LASID (Latin American Society for Immunodeficiencies; 2015

Sociedad argentina de inmunologia

Coeliac disease (CD) is caused by gluten ingestion in a subset of genetically predisposed individuals, necessitating strict life-long exclusion of dietary gluten. The adherence to a gluten free diet (GFD) has been estimated to be between 45?80%. Despite the proven benefits of the GFD, it can be exceedingly difficult to completely avoid gluten-containing foods. Monitoring of adherence to GFD should be based on a combination of history and serology (IgA TTG or IgA, IgG DGP antibodies). The aims of this study were to determine the factors that may influence the adherence to GFD and to study the role of antibodies in assessing adherence to the gluten-free diet in our population. Methods: Adults (>18 years old) diagnosed with biopsy confirmed CD for longer than one year participated in this study. All participants enrolled in the study by signing the approved informed consent form followed by completion of a factors questionnaire (FQ) and had blood drawn for IgA and IgG anti tissue transglutaminase (tTG) antibody titer and immunoglobulin A (IgA) level. Analysis of tTG titers was done by enzyme linked immunosorbent assay (ELISA) with recombinant human antigen (INOVA Quanta Lite human-tTG IgA and IgG, San Diego, USA; sensitivity 97%, specificity 99%). IgA was analyzed by radial immunodifusion. Results: Thirty three patients participated in this study, the mean age was 46. 85 +/-16.04 years; and 97% were women. The study population was found to adhere well to a GFD, with 72.7% being rated as high adherent (participant eats gluten fewer than one or three times per year or eats gluten one time per month) and the self reporting scoring indicated that 84 % adhere correctly to DLG. In this population, 59.4 % of the participant had adhered to GFD for 1 and 5 years and only 15.6 % had adhered for more than 10 years. After one year of GFD, IgA tTG antibodies were poor predictor of dietary transgressions (RR: 1.91, 95 % CI:0.72-5.09)and after five years of GFD these antibodies were regular predictors of dietary transgressions as well (RR: 2.45, 95% CI:0.48-12.46; 90% CI: 1.05-12.82). Conclusions: In our adult CD patients on a GFD, IgA-tTG-ab are poor predictors of dietary transgressions. The longer was the adherence to the diet, the better the role of antibodies as predictors of high adherence to GFD.