Autoimmune Thyroid, Celiac and Addison’s Diseases Related to HLA-DQ Types in Young Patients with Type 1 Diabetes in Belgium

Objective: To define the prevalence of auto antibodies (Ab) to different organs in young patients with type 1 diabetes (type 1DM). Methods: Ab to thyroid, celiac and adrenal disease was analyzed in 831 type 1 DM patients. Results: Hundred twenty-three (14.8%) had positive thyroid Ab. The risk of developing thyroid Ab was increased in girls (HR 2.3; 95% CI 1.6 3.2, p < 0.0001). Thirty-three (3.9%) patients had positive endomysium Ab (3.1% in girls and 3.5% in boys, p = NS). Adrenal Ab was detected in 5 patients. The DQA1*0301-DQB1*0301 haplotype was more prevalent in patients with thyroid Ab (p = 0.0281); DQA1*301-DQB1*302 and DQA1*501-DQB1*201 in patients with endomysium Ab (p = 0.0251 and p < 0.0001). All patients with adrenal Ab were DQA1*301-DQB1*302 positive. Conclusions: Type 1D patients should be screened annually for thyroid autoimmunity and celiac disease. The DQA1*0301-DQB1*0301 haplotype seems to confer susceptibility to thyroid autoimmunity, DQA1*301-DQB1*302 and DQA1*501-DQB1*201 to celiac disease and DQA1*301-DQB1*302 to adrenal autoimmunity.