Graves disease in ulcerative colitis:~The connection between Graves disease and Inflammatory bowel disease is well known in the literature, but thyroid disorders have not been considered extra-intestinal manifestations of ulcerative colitis. In most cases, the diagnosis of thyroid disease has preceded that of Inflammatory bowel disease . Early studies have suggested a relationship between thyroid abnormalities and ulcerative colitis .But it is still uncertain whether the coexistence of Grave's and ulcerative colitis diseases is due to a specific reason or a coincidence.~Concomitant Graves disease and ulcerative colitis; In general, the pathophysiology of ulcerative colitis is associated with theTh2 cytokine phenotype, and there is increased Th2 activity in Graves disease .Therefore, both Graves disease and ulcerative colitis are associated with a Th1/Th2 imbalance, with a dominance of Th2 responses. reported on a 26-year-old female who had a flare-up of ulcerative colitis and hyperthyroidism that was successfully treated with infliximab. In addition, they reported that theTh1/Th2 imbalance was improved 2 weeks after the initiation of infliximab therapy. However, it is still unclear whether Graves disease is an extra intestinal manifestation of ulcerative colitis or not Restricted to ulcerative colitis only, we found OR significantly increased for Grave's disease.~Increasing evidence suggests that Grave's disease (GD), an autoimmune thyroid disease (AITD) that accounts for 60%-80% of hyperthyroidism cases, might be related to the abnormal genetic expressions, imbalance of immune responses, increased Th2 activity and overgrowth of intestinal bacteria. For instance, the prior literature showed that some genetic factors, such as Human leukocytic antigen , PTPN22 and CTLA4, were associated with Graves disease Other studies also observed that hyperthyroidism with autoimmune gastritis is usually accompanied with low acid production that may subsequently lead to an overgrowth of intestinal bacteria Therefore, it is plausible that hyperthyroidism might be one of the potential risk factors for ulcerative colitis, because both ulcerative colitis and hyperthyroidism are polygenic diseases and may share analogous mechanisms Furthermore, genetic pathways and Th2-dominant immunological responses could contribute to the association between ulcerative colitis and hyperthyroidism.
Graves disease in ulcerative colitis:~The connection between Graves disease and Inflammatory bowel disease is well known in the literature, but thyroid disorders have not been considered extra-intestinal manifestations of ulcerative colitis. In most cases, the diagnosis of thyroid disease has preceded that of Inflammatory bowel disease. Early studies have suggested a relationship between thyroid abnormalities and ulcerative colitis . But it is still uncertain whether the coexistence of Grave's and ulcerative colitis diseases is due to a specific reason or a coincidence.