New concepts in ulcerative colitis:A thin line between medicine and surgery

Abstract

Although the vermiform appendix was generally regarded to be an evolutionary remnant, a substantial body of evidence has accumulated supporting its role in the development and course of UC. This thesis aims to investigate what the role of the appendix is in IBD, evaluate the natural history of UC, and demonstrate risk factors for postoperative complications after pouch surgery. Clinical studies were systematically reviewed and meta-analysed. The majority of the studies showed a significant inverse association between an appendectomy and the development of UC. Some studies found that previous appendectomy patients had a lower relapse rate, less steroid use and a decreased risk of colectomy. Furthermore, evidence elaborated in this thesis support the idea that a defective function and interaction with gut flora in the appendix play an essential role in the aetiology and probably also in the onset of UC. One third of UC patients with left-sided disease extended proximally during 10 years of follow up. The cumulative colectomy rate did not decrease over time. Anastomotic leakage represents a major early complication after IPAA surgery, which can lead to pouch dysfunction or pouch failure. Long-term disease course and the concurrent combination of steroid and anti-TNF treatment before IPAA surgery were independent risk factors for anastomotic leakage in IBD patients that underwent a proctocolectomy. Being overweight and high ASA score were independent risk factors in patients that underwent a completion proctectomy and IPAA at a later stage. These risk factors enable a tailored approach in patients undergoing IPAA surgery