Impact of the Ileal Microbiota on Surgical Site Infections in Crohn’s Disease: A Nationwide Prospective Cohort
Authors: Julien Clément , Anakok Emré , Treton Xavier , Nachury Maria , Nancey Stéphane , Buisson Anthony , Fumery Mathurin , Filippi Jérôme , Maggiori Léon , Panis Yves , Zerbib Philippe , François Yves , Dubois Anne , Sabbagh Charles , Rahili Amine , Seksik Philippe , Allez Matthieu , Lefevre Jérémie H ,   REMIND Study Group Investigators, Cattan Pierre , Chirica Mircea , Munoz-Bongrand Nicolas , Corte Hélène , Beaupel Nathan , Catry Jonathan , Gornet Jean-Marc , Baudry Clotilde , Lourenco Nelson , Maillet Mariane , Tran-Minh My-Linh , Chardiny Victor , Bonnet Joelle , Chedouba Leila , Nisard Andrée , Beaugerie Laurent , Bourrier Anne , Nion-Larmurier Isabelle , Kirchgesner Julien , Landman Cécilia , Quevrain Elodie , Brot Loic , Chafai Najim , Parc Yann , Debove Clothilde , Svreck Magali , Vincent Camille , Guedj Nathalie , Ferron Marianne , Bouhnik Yoram , Corcos Olivier , Stefanescu Carmen , Khabil Sarah , Marteau Philippe , Dray Xavier , Chaput Ulrika , Bommelaer Gilles , Goutte Marion , Denizot Jérémie , Barnich Nicolas , Coban Dilek , Desreumaux Pierre , Pariente Benjamin , Sommeville Coralie , Dupas Jean-Louis , Loreau Julien , Brazier Franck , Chatelain Denis , Attencourt Christophe , Leconte Martine , Boschetti Gilles , Flourié Bernard , Cotte Eddy , Charlois Anne-Laure , Falgon Peggy , Hadjisavvas Helena , Moussata Driffa , Chauvenet Marion , Boyer Sarah , Hebuterne Xavier , Arab Nadia , Barhoumi Raja , Hofmann Paul , Le Corff Sylvain , Bonnet Anna , Beyer-Berjot Laura , Sokol Harry 
Published: February 2022

Abstract

Background and Aims
Surgery is performed in 50–70% of Crohn’s disease [CD] patients, and its main risk is surgical site infection [SSI]. The microbiota has been extensively assessed in CD but not as a potential risk factor for septic morbidity. The objective of this study was to assess the impact of the gut microbiota on SSI in CD.

Methods
We used the multicentric REMIND prospective cohort to identify all patients who experienced SSI after ileocolonic resection for CD, defined as any postoperative local septic complication within 90 days after surgery: wound abscess, intra-abdominal collection, anastomotic leakage or enterocutaneous fistula. The mucosa-associated microbiota of the ileal resection specimen was analysed by 16S gene sequencing in 149 patients. The variable selection and prediction were performed with random forests [R package VSURF] on clinical and microbiotal data. The criterion of performance that we considered was the area under the Receiver Operating Characteristic [ROC] curve [AUC].

Results
SSI occurred in 24 patients [16.1%], including 15 patients [10.1%] with major morbidity. There were no significant differences between patients with or without SSI regarding alpha and beta diversity. The top selected variables for the prediction of SSI were all microbiota-related. The maximum AUC [0.796] was obtained with a model including 14 genera, but an AUC of 0.78 had already been obtained with a model including only six genera [Hungatella, Epulopiscium, Fusobacterium, Ruminococcaceae_ucg_009, Actinomyces and Ralstonia].

Conclusion
The gut microbiota has the potential to predict SSI after ileocolonic resection for CD. It might play a role in this frequent postoperative complication.