P459 Persistent mesorectal inflammatory activity is associated with complications after proctectomy in Crohn's disease. (16th January 2018)

• Record Type: Journal Article
• Authors: de Groof, E J; van der Meer, J H; Tanis, P J; de Bruyn, J R; van Ruler, O; D'Haens, G R; van den Brink, G R; Bemelman, W A; Wildenberg, M E; Buskens, C J
• Is Part Of: Journal of Crohn's and colitis. Volume 12:Number 1(2018:Jan.)Supplement 1
• Page Start: S336
• Page End: S337
• Publication Date: 2018-01-16
• Subjects: Inflammatory bowel diseases -- Periodicals; 616.344005
• DOI: 10.1093/ecco-jcc/jjx180.586
• Languages: English
• ISSNs: 1873-9946

Abstract

Abstract: Background: Rectal resection in inflammatory bowel disease (IBD) is frequently complicated by disturbed perineal wound healing. Close rectal dissection, where the mesorectum remains in situ, is hypothesised to reduce complications by minimising dead space compared with total mesorectal excision. The aim of this study was to analyse postoperative outcomes of both techniques in ulcerative colitis and Crohn's disease. In addition, immune-activity in mesorectal tissue was assessed. Methods: Perineal complications and healing were retrospectively assessed in a consecutive series of 74 IBD patients undergoing proctectomy using close rectal dissection or total mesorectal excision. Mesorectal tissue of 15 patients was analysed by FACS, immunofluorescence and in situ hybridisation. Based on the combined clinical and in vitro findings, a novel surgical approach for Crohn's patients with disturbed perineal healing after proctectomy was developed and assessed in a prospective case series of eight patients. Results: In Crohn's disease, perineal complications were more frequent after close rectal dissection than after total mesorectal excision (59.5% vs. 17.6%; p = 0.007) with lower healing rates (51.4% vs. 88.2%; p = 0.014). No significant differences were observed in ulcerative colitis. Compared with ulcerative colitis as well as non-IBD controls, the mesorectal tissue of Crohn's disease patients contained enhanced numbers of macrophages with a pro-inflammatory phenotype, including high expression of CD14, production of TNFα and decreased expression of the wound healing associated marker CD206. As these results suggest a pro-inflammatory status of the mesorectum in Crohn's disease, mesorectal excision with omentoplasty was performed in eight patients with persistent presacral abscess after close rectal dissection. This procedure resulted in complete perineal wound closure in six of eight patients and partial closure in the remaining two patients. Evaluation of the mesorectal tissue indeed showed ongoing inflammatory characteristics despite prior removal of the affected bowel in these patients. Conclusions: In Crohn's disease, close rectal dissection resulted in increased numbers of perineal complications, associated with a pro-inflammatory immune status of the mesorectal tissue. Excision of this pro-inflammatory mesenteric tissue resulted in strong improvement in perineal healing rates.