Abstract
Background
Observational data in children and RCT data in adults indicate that methotrexate (MTX) is associated with induction and maintenance of clinical remission in luminal Crohn’s disease, but efficacy in achieving intestinal healing has not been examined.
Aims
To examine the evolution of MRE signs of inflammation in children treated with MTX.
Methods
In this retrospective cohort study, we reviewed paediatric CD patients on maintenance MTX monotherapy for >4 months who underwent serial MREs between July 2010 and October 2015. MREs were reviewed by a radiologist blind to clinical data. Overall inflammatory activity on each MRE was scored as minimal, mild, moderate or severe, informed by the presence of bowel wall thickness, wall enhancement, T2 hyperintensity, comb sign, mesenteric edema, penetrating disease, stricturing, diffusion restriction and motility. The radiologist’s global assessment of change from MRE 1 to MRE 2 was scored as improved, unchanged or worsened. Clinical findings, disease activity (assessed by weighted paediatric CD activity index [wPCDAI]) and surgical history were also extracted from medical records by a clinician blind to MRE results.
Results
Thirty-five patients were included (median age at diagnosis 12 [IQR 11–14] years; 77% male; 60% inflammatory (B1), 17% stricturing (B2), 23% penetrating (B3) disease). Between baseline and follow-up MRE, wPCDAI (median 15 [IQR 7–43] decreased to 8 [IQR 0–18]; p=0.006) and CRP (median 9 [IQR 2–36] decreased to 5 [IQR 5–9]; p=0.013) and 74% (N=26) were in clinical remission (wPCDAI < 12.5) at MRE 2. MRE features that significantly improved from MRE 1 to 2 were comb sign from 63% (N=37) to 38% (N=14) (p=0.02) and penetrating disease from 14% (N=8) to 0 (p=0.03). After a median of 17 months (IQR 13–23), 51% (N=18) of patients improved, 29% (N=10) worsened and 20% (N=7) had no change based on the radiologist’s global assessment. Of the 21 patients with moderate/severe disease at MRE 1, 33% (N=7) had minimal/mild disease by MRE 2. 66% (N=14/21) continued to have moderate/severe disease at MRE 2. Additionally, a further 14% (N=2/14) of those with minimal/mild disease at baseline MRE progressed to moderate/severe disease at MRE 2. Complete details of change between MRE 1 and MRE 2 are displayed in Figure 1.
Conclusions
Despite signs of clinical improvement, many paediatric CD patients on maintenance MTX therapy for >4 months have unchanged or worsened MRE findings. This underscores the need for follow-up imaging in these cases.
Funding Agencies
None