Gastric parietal cell antibodies are associated with glutamic acid decarboxylase-65 antibodies and the HLA DQA1*0501-DQB1*0301 haplotype in Type 1 diabetes mellitus

Aims To assess the prevalence of thyrogastric autoimmunity in relation to age, sex, beta-cell antibody status and HLA DQ haplotypes in Type 1 diabetes mellitus. Methods One hundred and seventy-one patients with Type 1 diabetes mellitus were studied (male/female 86/85: mean age 19 +/- 11 years; duration of diabetes 5 +/- 4 years). Islet cell antibodies (ICA) and parietal cell antibodies (PCA) were measured using indirect immunofluorescence; glutamic acid decarboxylase-65 antibodies (GADA) by radiobinding assay and thyroid peroxidase antibodies (TPO) with an immunoradiometric assay (IRMA). Results The majority of subjects (81.3%) showed one or more autoantibodies. The prevalence rates were: GADA 64,9%, ICA 46.2%, PCA 19.9% and TPO 19.3%, Patients with ICA+ greater than or equal to 3 years after diagnosis had a higher prevalence of GADA (P = 0,03, odds ratio (OR) 2.66) and thyrogastric antibodies (P = 0.05, OR 2.23) than subjects ICA- after 3 years. PCA+ patients were older (P = 0.04), had a higher prevalence of GA.DA (P = 0.005, OR 3.89) and TPO (P = 0.05, OR 2.50) than PCA- subjects. Logistic regression analysis showed that PCA status was determined by the HLA DQB1*0501-DQB1*0301 haplotype (beta = 2.94, P = 0.04) and GADA status (beta = 2,44, P=0.041). Conclusions Thyrogastric antibodies are highly prevalent in Type 1 diabetes mellitus, especially in patients with persisting ICA, Screening for gastric autoimmunity is particularly advised in patients who are positive for GADA and for the HLA DQA1*0501-DQB1*0301 haplotype.