Background: High diagnostic accuracy is reported for magnetic resonance enterography (MRE) in Crohn’s disease (CD), but few studies have evaluated its role in abdominal fistulae. The primary aim of this study was to assess the reliability of MRE in the identification of internal fistulae in CD.
Methods: One hundred and eighty-six patients with moderate CD (CD Activity Index : 250–400) were prospectively selected from the inflammatory bowel disease clinic of Parma University Hospital. Eligible patients had already undergone nutritional screening, pancolonoscopy, and computed tomography enterography (CTE) in the month before enrollment. MRE was performed according to the study protocol. Additional fluoroscopic contrast-enhanced studies or surgical evaluation were used for discordance between CTE and MRE results. A consensus committee resolved equivocal findings. Surgical findings and/or fluoroscopic contrast-enhanced studies together with the clinical data were considered the composite “reference standard” to which the results of MRE were compared.
Results: MRE identified 22 internal fistulae in 21 patients (11%), of whom 4 (19%) also had perianal fistulae and found 7 abscesses (33%). Forty-one (22%) additional patients with perianal fistulae were identified. Thirteen patients (57%) with internal fistulae required enteral nutrition support. No statistically significant differences were found between MRE and CTE in fistula detection. There was also no significant difference between MRE and the composite diagnosis in those who underwent surgery (n = 8) and/or contrast-enhanced studies (n = 7).
Conclusions: CTE and MRE accurately detect internal fistulae in CD. MRE is preferable because it avoids radiation. Reliable identification of internal fistulae by MRE should permit earlier and improved treatment.
Article first published online 11 June 2013
*Department of Gastroenterology, University College London Hospitals, London, United Kingdom;
†Department of Gastroenterology,
‡Department of Radiology, and
§Department of Surgical Science, General Surgery and Organ Transplantation, University of Parma, Parma, Italy;
‖Department of Radiology, University College London Hospitals, London, United Kingdom;
¶Molecular and Nutritional Epidemiology Unit, Institute for Study and Prevention in Oncology, Florence, Italy; and
**Department of Radiology, Erasmus Medical Centre, Rotterdam, the Netherlands.
Reprints: Alastair Forbes, MD, Centre for Gastroenterology and Clinical Nutrition, Rockefeller Building, University College London, Gower Street, London WC1E 6BT, United Kingdom (e-mail: firstname.lastname@example.org).
Supported by the Comprehensive Biomedical Research Centre at UCL and UCH from the United Kingdom National Institute for Health Research.
The authors have no conflicts of interest to disclose.
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Received October 19, 2012
Accepted February 25, 2013