Inflammatory bowel disease is a condition caused by gastrointestinal immune system dysregulation and affected by both genetic and environmental factors. Differences in intestinal bacteria exist between IBD patients and healthy controls, but the role of intestinal bacteria in the development and treatment of IBD remains largely unknown. Fecal microbiota transplantation (FMT) is the transfer of gastrointestinal bacteria from a healthy donor to a patient with altered microbial diversity with the intent of restoring a normal bacterial balance. Most studies focus on its use in treating Clostridium difficile (CDI), an infection characterized by dysbiosis. Given the role of dysbiosis in IBD, the investigators hypothesize that FMT may be beneficial in IBD. The purpose of this study is to prospectively examine the safety of FMT in the management of ulcerative colitis (UC).

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) with significant morbidity and mortality. Current therapies remain limited by side effects and loss of response over time, and there is an ongoing need for new therapies. Fecal microbiota transplantation (FMT), which has proven to be safe and effective in the management of Clostridium difficile infection (CDI) has been proposed as a therapy for UC. There have been studies examining the role of FMT in UC, but they have shown mixed results, and have not examined the underlying immunologic and microbial changes to explain how and why FMT works from specific donors and in certain recipients. Furthermore, no studies have examined the long-term safety of FMT in patients with UC. This proposal aims to examine: (a) the short- and long-term safety of FMT in patients with UC, (b) the efficacy of FMT as a therapy for mild-moderate UC, and (c) the microbial and immunologic changes that occur after FMT, to help understand how and why it works in this group of patients.

Inclusion Criteria:

• Patients with biopsy proven ulcerative colitis (UC), including those with inadequately controlled UC (flare) as defined by failure of standard medical therapy, steroid-dependence, and/or need for escalation of medical care as determined by severity index (Mayo Score), endoscopic or histologic study, and/or medical provider
• Have active disease, defined with a Mayo Score > 3 and Mayo endoscopic subscore >1
• Subjects whom the investigator believes can and will comply with the requirements of the protocol
• Able to provide informed written consent.

Exclusion Criteria:

• Biopsy-proven Crohn's disease or indeterminate colitis
• Acute abdomen or other clinical emergencies requiring emergent management (for example: stricture, bowel obstruction, perforation and/or abscess)
• Primary sclerosing cholangitis (PSC)
• Pregnancy
• Concurrent Clostridium difficile infection or other known infection
• Prior history of fecal microbiota transplantation
• Other causes of diarrhea, including but not limited to tube feeds and medications (for example, kayaxelate, metformin, lactulose, laxatives, magnesium)
• Major congenital defects
• Subjects with recent malignancy in the last 5 years, excluding non-melanoma skin malignancies
• Anaphylactic reactions to any foods
• Any antibiotic use within the last 3 months
• Subject having any other condition that, in the opinion of the investigator, would jeopardize the safety or rights of the participant participating in the study, would make it unlikely for the participant to complete the study, or would confound the study