Clinical Features and Therapeutic Outcomes of Post-colectomy Enteritis with Ulcerative Colitis

Objectives: Few reports are available on post-colectomy enteritis (PCE) with ulcerative colitis (UC), which can be severe and sometimes fatal. The clinical characteristics are unclear, and treatment and diagnosis protocols have not been established. We aimed to investigate the incidence, clinical characteristics, diagnostic criteria, and therapeutic outcomes of PCE in this study. Methods: Patients with UC who underwent colectomy between April 2010 and December 2019 were included in this study. We retrospectively analyzed patients who developed PCE and excluded patients with other forms of enteritis. Results: We performed 829 colectomies because of a preoperative diagnosis of UC. Eleven and four patients were diagnosed with Crohn's disease and indeterminate colitis after surgery, respectively; 22 patients developed enteritis in the perioperative period. We excluded six patients with backwash ileitis, five with prepouch ileitis, three with infectious enteritis, and one with ischemic enteritis. In total, 7/814 (0.8%) patients developed PCE. All patients with PCE had pancolitis. PCE was observed a median of 33 (12-248) days after surgery. Endoscopy showed friable and granular mucosa. The extent of disease included various types such as pan-enteritis with diffuse type, pan-enteritis and mild inflammation in the middle ileum, and only ileitis. Gastroduodenitis-associated UC developed in 6/7 cases. All patients improved with tumor necrosis factor alpha (TNFα) antagonists even if TNFα antagonists had not been effective for colitis. Conclusions: PCE was rare. The mucosal endoscopic findings were similar to those of UC, and the extent of disease varied. TNFα antagonist administration for PCE was effective.