Targeting the gut layers in Crohn’s disease: mucosal or transmural healing?

ABSTRACT

Introduction

Although the landmark of Crohn’s Disease (CD) is the transmural inflammation, mucosal healing (MH), which is assessed by colonoscopy, is currently the gold standard of CD management. Transmural healing (TH) is a new concept evaluated by cross-sectional imaging (CSI) techniques, such as bowel ultrasound (US), computed tomography enterography (CTE), and magnetic resonance enterography (MRE). Little is known about the clinical significance of persisting mural disease and the predictive value of complete TH.

Areas covered

The authors reviewed the available literature on TH and its meaning as predictor of long-term outcomes in CD, to explore if TH may be a better target compared to MH in CD patients, in terms of disease outcome, such as medication changes, hospitalization, or surgery.

Expert opinion

Some evidence suggests that achieving TH has a predictive value in CD management and correlates with better disease outcome than MH, although existing studies are few and with limitations. A definitive definition of TH is not yet established and the frequency or the preferred modality of TH evaluation remains unclear. Implementing TH in treat-to-target approach may enable stricter disease monitoring with noninvasive methods and finally change the disease course, preventing irreversible bowel damage.

KEYWORDS:

• Bowel ultrasound
• computed tomography enterography
• Crohn’s disease
• magnetic resonance enterography
• mucosal healing
• outcomes
• transmural healing

Article highlights

• TH is a new concept in CD management, evaluated by cross-sectional imaging techniques, such as bowel ultrasound, computed tomography enterography, and magnetic resonance enterography.

• MH is assessed by colonoscopy and is currently the gold standard in treat-to-target therapeutic approach, since it was shown to predict better long-term outcomes, like lower need of steroids, hospitalization, and surgery.

• TH, evaluated by US, MRE or CTE, has a predictive value in CD management and correlates with better disease outcome than MH, although existing studies are few and with limitations.

• Further research is needed to establish the definition of TH and the frequency or the preferred modality of TH evaluation.

• Finally, large prospective controlled studies are needed, before using TH as a goal of management for CD in clinical practice.

Declaration of interest

M Allocca has received funds from the Nikkiso Europe and lecture fees from Janssen, AbbVie, and Pfizer. G Fiorino is a consultant and a member of the advisory boards for MSD, Takeda Pharmaceuticals, AbbVie, Pfizer, Celltrion, Amgen, Sandoz, Samsung, and Jannsen Pharmaceuticals. G Fiorino is a consultant and an advisory board member for MSD, Takeda Pharmaceuticals, AbbVie, Pfizer, Celltrion, Amgen, Sandoz, Samsung, and Janssen Pharmaceuticals. F Furfaro received consulting fees from Amgen, AbbVie, and lecture fees from Janssen pharmaceutical and Pfizer. D Gilardi receives consulting fees from Nikkiso GMHB, Sofar spa, Biofer Spa, and Roche. They also received lecture fees from Johnson and Johnson, Pfizer, and Janssen Pharmaceuticals. L Peyrin-Birolet receives personal fees from Merck, AbbVie, Janssen Pharmaceuticals, Genetech, Mitsubishi, Ferring, Norgine, Tillots, Vifor, Hospira/Pfizer, Celltrion, Takeda, Biogaren, Boehringer-Ingelheim, Lilly, HAC-Pharma, Index Pharmaceuticals, Amgen, Sandoz, Forward Pharma GmbH, Celgene, Biogen, Lycera, and Samsung Biosepsis. S Danese reports personal fees from AbbVie, Ferring, Hospira, Johnson and Johnson, Merck, Millennium Takeda, Mundipharma, Pfizer, Tigenix, UCB Pharma, and Vifor.

The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.