Meta-Analysis
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 21, 2019; 25(31): 4555-4566
Published online Aug 21, 2019. doi: 10.3748/wjg.v25.i31.4555
Layered enhancement at magnetic resonance enterography in inflammatory bowel disease: A meta-analysis
Davide Bellini, Flaminia Rivosecchi, Nicola Panvini, Marco Rengo, Damiano Caruso, Iacopo Carbone, Riccardo Ferrari, Pasquale Paolantonio, Andrea Laghi
Davide Bellini, Flaminia Rivosecchi, Nicola Panvini, Marco Rengo, Iacopo Carbone, Department of Radiological Sciences, Oncology and Pathology, "Sapienza" University of Rome, I.C.O.T. Hospital, Latina 04100, Italy
Damiano Caruso, Andrea Laghi, Department of Surgical and Medical Sciences and Translational Medicine, “Sapienza”-University of Rome, Sant'Andrea University Hospital, AOU Sant’Andrea, Rome 00189, Italy
Riccardo Ferrari, Department of Emergency Radiology, San Camillo-Forlanini Hospital, Rome 00152, Italy
Pasquale Paolantonio, Department of Radiology, San Giovanni Hospital, Rome 00184, Italy
Author contributions: Bellini D conception and design of the study, acquisition of data, analysis and interpretation of data, drafting the article, critical revision, final approval; Rivosecchi F acquisition of data, analysis and interpretation of data, drafting the article, revising the article, final approval; Panvini N acquisition of data, analysis and interpretation of data, drafting the article, revising the article, final approval; Rengo M analysis and interpretation of data, revising the article, final approval; Caruso D analysis and interpretation of data, revising the article, final approval; Carbone I analysis and interpretation of data, revising the article, final approval; Ferrari R interpretation of data, revising the article, final approval; Paolantonio P interpretation of data, revising the article, final approval; Laghi A conception and design of the study, analysis and interpretation of data, critical revision, final approval.
Conflict-of-interest statement: The authors deny any conflict of interest.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
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/
Corresponding author: Andrea Laghi, MD, Full Professor of Radiology, Department of Surgical and Medical Sciences and Translational Medicine, “Sapienza”-University of Rome, Sant'Andrea University Hospital, AOU Sant’Andrea, Via di Grottarossa, 1035-1039, Rome 00189, Italy. andrea.laghi@uniroma1.it
Telephone: +39-335-8100145 Fax: +39-06-33775610
Received: March 26, 2019
Peer-review started: March 28, 2019
First decision: June 6, 2019
Revised: June 25, 2019
Accepted: July 19, 2019
Article in press: July 19, 2019
Published online: August 21, 2019
Abstract
BACKGROUND

Documentation of disease activity in patients affected by Crohn’s disease (CD) is mandatory in order to manage patients properly. Magnetic resonance imaging (MRI) is considered the reference cross-sectional technique for the assessment of CD activity. Among MRI findings, layered pattern (LP) of contrast enhancement seems to be one of the most significant signs of severe disease activity; however, it has also been associated with chronic disease and mural fibrosis.

AIM

To systematically evaluate the accuracy of LP of contrast enhancement in the diagnosis of active inflammation in patients with CD.

METHODS

In February 2019, we searched the MEDLINE and Cochrane Central Register of Controlled Trials databases for studies evaluating the diagnostic accuracy of LP of contrast enhancement on MRI for the detection of active inflammation in patients with CD. To be included, studies had to use histopathologic analysis (endoscopy or surgery) as the reference standard. Risk of bias and applicability concerns of the included studies were evaluated by using items from the Quality Assessment for Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Pooled sensitivity and specificity were determined using a bivariate random-effect model. Heterogeneity was quantified by using the I2 statistic. Our meta-analysis received no funding, and the review protocol was not published or registered in advance.

RESULTS

Of the 1383 studies identified, five articles were finally selected for quantitative and qualitative synthesis (245 patients, 238 of whom had histopathologically confirmed CD, 144 with active inflammation and 94 with inactive disease). The meta-analysis showed a pooled sensitivity of 49.3% (95%CI: 41%-57.8%; I2: 90.7%) and specificity of 89.1% (95%CI: 81.3%- 94.4%; I2: 48.6%). Pooled PLR and NLR were 3.3 (95%CI: 1.9-5.7; I2: 6.1%) and 0.6 (95%CI: 0.5-0.9; I2 70.5%), respectively. SDOR was 6.8 (95%CI: 2.6-17.6; I2: 27.1%). The summary ROC curve showed an area under the curve (AUC) of 0.82 (SE 0.06; Q* 0.76). High risk of bias and applicability concerns were observed in the domains of patient selection for one included study.

CONCLUSION

LP on contrast-enhanced MRI is a specific finding to rule out active inflammation in patients with CD. Further studies using a prespecified definition of LP on contrast-enhanced MRI are needed to support our findings.

Keywords: Crohn’s disease, Diagnostic imaging, Magnetic resonance imaging, Inflammation, Fibrosis, Sensitivity and specificity, Meta-analysis

Core tip: Magnetic resonance imaging (MRI) plays a critical role in the assessment of Crohn’s disease (CD) activity and severity. Layered pattern (LP) of contrast enhancement is frequently observed in patients with active disease; however, its relevance remains controversial, since it has also been correlated with the presence of mural fibrosis and chronic disease. Our systematic review and meta-analysis showed that LP on contrast-enhanced MRI yields high specificity for active inflammation and can reliably rule out the presence of active disease in patients with CD.