Kono-S anastomosis for Crohn's disease: narrative - a video vignette

The role of Kono-S anastomosis and mesenteric resection in reducing recurrence after surgery for Crohn's disease: a systematic review

AIM

Recurrence after surgery for Crohn's disease is common. Anastomotic configuration may influence recurrence and the mesentery may be key. Recently the Kono-S anastomosis and radical mesenteric excision have been proposed as methods of reducing recurrence. We analysed the literature pertaining to these novel techniques.

METHOD

We searched MEDLINE, Embase and the Cochrane Library for, and selected, studies evaluating Kono-S anastomosis and/or radical mesenteric excision in Crohn's disease. We assessed methodological quality and risk of bias using the Cochrane risk of bias tool for randomized controlled trials and the Joanna Briggs Institute tool for nonrandomized trials. A narrative synthesis was used to summarize the findings.

RESULTS

Nine studies (896 patients) were identified. Apart from one randomized controlled trial with a low risk of bias the overall level of evidence was poor (Grade IV). The Kono-S anastomosis was associated with a lower incidence of endoscopic and surgical recurrence (0%-3.4% vs 15%-24.4% respectively). Complications, particularly anastomotic leak rate, were also lower (1.8% vs 9.3% respectively). Evidence from a single poor quality study suggested that mesenteric excision may reduce surgical recurrence rates compared with mesentery preservation.

CONCLUSION

The existing literature suggests that the Kono-S anastomosis is safe and may reduce endoscopic and surgical recurrence, but level of evidence is mainly poor. One element of the Kono-S technique, preservation of the mesentery, may be detrimental to recurrence. Further, higher quality, studies are required to investigate these techniques. Such studies should consider the impact of the degree of mesenteric resection in addition to the anastomosis on disease recurrence.

Kono-S Anastomosis for Surgical Prophylaxis of Anastomotic Recurrence in Crohn's Disease: an International Multicenter Study

INTRODUCTION

The Kono-S (antimesenteric functional end-to-end handsewn) anastomosis has been used for Crohn's disease in Japan and the USA since 2003 and 2010, respectively. This technique was designed to reduce the risk of anastomotic surgical recurrence. This study reviews the outcomes a decade after the introduction of the Kono-S anastomosis to clinical practice.

METHODS

This study was conducted at five hospitals (four in Japan and one in the USA). A total of 187 patients in Japan (144 patients, group J) and the USA (43 patients, group US) who underwent Kono-S anastomosis for Crohn's disease between September 2003 and September 2011 were included.

RESULTS

With a median follow-up of 65 months, two surgical anastomotic recurrences have occurred in group J. Kaplan-Meier analysis showed that 5 and 10 years surgical recurrence-free survival rate was 98.6% in group J. No surgical anastomotic recurrences have been detected in group US with a median follow-up of 32 months. The Kono-S anastomosis was technically feasible and performed in all patients.

CONCLUSION

The Kono-S anastomosis appears to be safe and effective in reducing the risk of surgical recurrence in Crohn's disease.