Magnetic resonance enterographic predictors of one-year outcome in ileal and ileocolonic Crohn's disease treated with anti-tumor necrosis factor antibodies

Abstract

The aim of the study was to assess the role of magnetic resonance enterography (MRE) in predicting one-year efficacy of anti-tumor necrosis factor antibodies--infliximab (IFX), adalimumab (ADA) in Crohn's disease (CD) patients primarily responding to therapy. We performed retrospective analysis among 61 CD patients who had undergone a successful IFX/ADA induction therapy and were treated with maintenance doses. All patients underwent MRE at week 0. We assessed which MRE features were predictive for steroid-free remission at week 52, and which were associated with a secondary loss of response. 44 patients were in steroid-free remission at week 52, 17--were secondary non-responders. The ROC curve showed that bowel thickening with contrast enhancement analyzed together at week 0 were associated with steroid-free remission at week 52 (p = 0.01; AUC 0.67). Bowel stenosis with or without prestenotic dilatation [OR 5.8 (95% CI 1.4-25) and 2.4 (95% CI 1.2 - 5) respectively; p = 0.01] and the presence of intra-abdominal fistulas [OR 1.4 (95% CI 1.1-2); p=0.004] were related to secondary non-response. A high baseline inflammatory activity detected by MRE predicts one-year response in CD after IFX/ADA. In case of bowel stenosis, intra-abdominal fistulas, other therapeutic options should be considered.

Figure 1

Receiver operator characteristic (ROC) curve showing that the score assessing bowel inflammatory thickening with contrast enhancement in the baseline magnetic resonance enterography (range 0 – 4 points) was predictive for long-term steroid-free remission at week 52 in Crohn’s disease patients treated with anti-TNF antibodies. An optimal cut-off point was ≥ 3, and it allowed to predict with 67% (confidence interval: 52 – 81%) sensitivity and 65% (confidence interval: 39 – 86%) specificity achievement of the primary therapeutic end point of the study (p = 0.01; area under the curve 0.67).

Figure 2

Magnetic resonance enterography images illustrating an example of a response to one-year anti-tumor necrosis factor (anti-TNF) therapy in a patient with Crohn’s disease: (a) Week 0 - before anti-TNF therapy. T2-weighted sequence demonstrating thickening of a bowel wall (white arrows) without stenosis of the bowel lumen. (b) Week 0 - before anti-TNF therapy. Dynamic contrast enhanced T1-volume interpolated gradient-echo sequence demonstrating thickening of a bowel wall with enhancing in the various layers of the wall - hyperintense signal corresponding to edema in acute inflammation (white arrows). (c) Week 52. T2-weighted sequence demonstrating decrease of thickening of the bowel wall (white arrows) after one-year anti-TNF therapy. (d) Week 52. Dynamic contrast enhanced T1-volume interpolated gradient-echo sequence demonstrating decrease of thickening of the bowel wall with moderate enhancement typical for moderate activity of inflammation (white arrows) - after one-year anti-TNF therapy.

Figure 3

Magnetic resonance enterography images illustrating an example of a non-response to one-year anti-tumor necrosis factor (anti-TNF) therapy in a patient with Crohn’s disease: (a) Week 0 - before anti-TNF therapy. T2-weighted sequence demonstrating thickening of a bowel wall (white arrows) with stenosis of the bowel lumen with prestenotic dilatation (asterisk). (b) Week 0 - before anti-TNF therapy. Dynamic contrast enhanced T1-volume interpolated gradient-echo sequence demonstrating thickening of a bowel wall with enhancing in the various layers of the wall - hyperintense signal corresponding to edema in acute inflammation and dilatation of lumen (white arrows). (c) Week 52. T2-weighted sequence demonstrating increase of thickening of the bowel wall (white arrow) with stenosis of lumen and prestenotic dilatation (asterisk) after one-year anti-TNF therapy. (d) Week 52. Dynamic contrast enhanced T1-volume interpolated gradient-echo sequence demonstrating increase of thickening of the bowel wall with enhancement typical for activity of inflammation (white arrows) – after one-year anti-TNF therapy.