P197. Magnetic resonance enterography for the assessment of Crohn's disease: changing imaging paradigms?
K.L. White1, S. Soteriadou1, K. McWhirter1, R. Filobbos2, J.K. Limdi1, 1Pennine Acute Hospitals, Gastroenterology, Manchester, United Kingdom, 2Pennine Acute Hospitals, Radiology, Manchester, United Kingdom
Advances in therapy and definitions of inflammatory bowel disease (IBD) control have led to increasing reliance on imaging. Awareness of effects of ionizing radiation has placed emphasis on radiation-free imaging. We assessed the role of magnetic resonance enterography (MRE) in small bowel Crohn's disease (CD).
We conducted a retrospective review of 701 MRE studies between 2009 and 2012 at our institution. Clinical data (demographics, disease characteristics and therapy) were obtained from electronic record review. Inflammatory markers, radiological tests and ileocolonoscopy within 90 days of MRE were recorded. MRE reports were recorded using accepted activity criteria – small bowel dilatation, stenosis, wall thickening, enhancement, mucosal irregularity, mesenteric inflammation, hypervascularity, lymph node enlargement, abscesses, fistulation and extraintestinal features.
Of 336 patients with IBD, 293 had CD (174 of these female; mean age 35; range 16–71) and median disease follow up 4 years (range 0–39).
Abnormalities were noted in 212 scans; 115 had active non-stricturing, 88 active stricturing and 9 fibrostenotic disease. Within active groups, there were 18 fistulae and 8 abscesses in 20 patients. Ileo-colonoscopy was performed in 50 patients with active non-stricturing disease with 41/50 showing active colitis and raised CRP in 46/102. Treatment was increased in 59% of the active non-stricturing group, 20/68 to azathioprine, 20/68 to infliximab, 7/68 to surgery, 12/68 had 5-ASA with no change in 41%, of whom 8/20 had normal ileo-colonoscopy and 37/44 normal CRP.
In 50% of active stricturing group, treatment was increased to azathioprine in 9, biologics (25) and 14 to surgery. Thirty-two of 63 patients in the group had an elevated CRP and 19/28 active colitis at ileo-colonoscopy.
Of 80 normal MRE, treatment was unchanged in 96%; with normal CRP in 57/73 and ileo-colonoscopy in 14/30.
Of 9 fibrostenotic subjects, eight had normal CRP and 4 had mild colitis at colonoscopy. Two had surgery and 4 had no change as MRE showed improved appearances (2 commenced steroids and 1 changed to adalimumab). In the abscess/fistula group 3 had surgery, 6 had infliximab (fistula), 1 had adalimumab (fistula) and 2 were treated with antibiotics.
The choice of small bowel investigation will be driven by the clinical question, available expertise and economic factors. MRE aids assessment of CD, identifying patients with active disease for meaningful treatment escalation.