Editorial
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 14, 2017; 23(34): 6197-6200
Published online Sep 14, 2017. doi: 10.3748/wjg.v23.i34.6197
Defining and predicting deep remission in patients with perianal fistulizing Crohn’s disease on anti-tumor necrosis factor therapy
Konstantinos Papamichael, Adam S Cheifetz
Konstantinos Papamichael, Adam S Cheifetz, Center for Inflammatory Bowel Diseases, Division of Gastroenterology, Beth-Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
Author contributions: Papamichael K wrote the manuscript; Cheifetz AS contributed to the manuscript critical revision; all authors approved the final version of the article.
Conflict-of-interest statement: Papamichael K has nothing to disclose; Cheifetz AS has received consultancy fees from AbbVie, Janssen, Takeda, Ferring, AMAG, Miraca and Pfizer.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Konstantinos Papamichael, MD, PhD, FEBGH, Center for Inflammatory Bowel Diseases, Division of Gastroenterology, Beth-Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Ave., Boston, MA 02215, United States. kpapamic@bidmc.harvard.edu
Telephone: +1-617-6672802 Fax: +1-617-6675826
Received: July 28, 2017
Peer-review started: July 28, 2017
First decision: August 10, 2017
Revised: August 16, 2017
Accepted: September 5, 2017
Article in press: September 5, 2017
Published online: September 14, 2017
Abstract

Perianal fistulas can occur to up to one-third of patients with Crohn’s disease (CD) leading to significant disabling disease and morbidity. Fistulising perianal CD treatment often necessitates a combined pharmacological and surgical approach. Anti-tumor necrosis factor (anti-TNF) therapy, particularly infliximab, has been shown to be very effective for both perianal and internal fistulising CD. Nevertheless, current data suggest that sustained remission and long-term complete fistula healing can be achieved in only 30% to 50% of patients. Moreover, these percentages refer mostly to clinical rather than deep remission, defined as endoscopic and radiologic remission, which is quickly emerging as the preferred goal of therapy. Unfortunately, the therapeutic options for perianal fistulising CD are still limited. As such, it would be of great value to be able to predict, and more importantly, prevent treatment failure in these patients by early and continued optimization of anti-TNF therapy. Similar to ulcerative colitis and luminal CD, recent data demonstrate that higher infliximab concentrations are associated with better clinical outcomes in patients with perianal fistulising CD. This suggests that therapeutic drug monitoring and a treat-to-trough therapeutic approach may emerge as the new standard of care for optimizing anti-TNF therapy in patients with perianal fistulising CD.

Keywords: Inflammatory bowel disease, Infliximab, Adalimumab, Magnetic resonance imaging, Drug monitoring, Fistula healing

Core tip: Defining and predicting deep remission is important to guide the management of patients with perianal fistulizing Crohn’s disease (CD). Deep remission, defined as complete fistula healing based on objective endoscopic and radiologic findings, should be the goal of care in the treatment of patients with perianal CD. Currently, anti-tumor necrosis factor (anti-TNF) are the standard of care for perianal CD, but long-term outcomes are disappointing. Data suggests that higher infliximab concentrations are associated with better clinical outcomes in patients with perianal fistulising CD and thus therapeutic drug monitoring may be a valid therapeutic strategy for optimizing anti-TNF therapy towards improved objective outcomes and deep remission.