These diseases may concur with Hashimoto's thyroiditis (HT), the most common cause of hypothyroidism, in polyglandular autoimmune syndrome type III b (26), since Hashimoto's thyroiditis and Crohn disease are CD4+T helper (Th) 1-polarized (27–30) disorders, while UC is an atypical Th2-polarized disease (27). This evidence concerns the gene CD4 and Hashimoto thyroiditis.