Ulcerative colitis (UC) is a subtype of inflammatory bowel disease (IBD) that causes relapsing and remitting inflammation in the colon and rectum. Numerous treatment options are available for patients with UC including biologics and small molecule inhibitors that target the immune system. Although these therapies have dramatically improved options for patients with IBD, there remains a modest ceiling for their overall efficacy. Currently there are no biomarkers that can guide treatment decisions in patients with UC.