ESPE Abstracts

Background: Biologic therapy may improve bone health, body composition, and muscle function in children with inflammatory bowel disease but the extent of improvement are unclear.

Objective and hypotheses: To evaluate bone and muscle mass in children with inflammatory bowel disease (IBD) following infliximab (IFX) therapy.

Method: Prospective longitudinal study of 19 children (12M), 17 Crohn’s disease (CD), one ulcerative colitis (UC), one inflammatory bowel disease unclassified (IBDU) of bone evaluation commencing treatment with IFX. Bone and muscle parameters were measured by pQCT at the non-dominant distal radius at 4 and 66% at baseline and 6 months. pQCT parameters for area were adjusted for height.

Results: At baseline 7/19 (37%) had moderate/severe disease activity whereas at 6 months this was 1/19 (5%). Nine children (47%) who were on oral prednisolone at baseline discontinued at 6 months. Seven children (37%) were not on oral prednisolone at baseline and 6 months. One child (5%) who was not on oral prednisolone at baseline was on prednisolone at 6 months whereas two children were on oral prednisolone at baseline and 6 months. For all cohort median volumetric BMD Z was −1.4 (−2.8, −0.4) at baseline and −1.4 (−2.8, −0.4) at 6 months (P=0.64) and muscle area Z score were −1.8 (−4.3, −0.3) and −2.1 (−3.5, −0.5) (P=0.93). Total alkaline phosphatase (U/l) increased from 97 (37, 259) at baseline to 153 (29, 391) at 6 months (P=0.001). In the seven children who were not on oral prednisolone at baseline and 6 months, volumetric BMD Z score were −0.9 (−2.1, 0.0) and −0.7 (−2.2, −0.3) (P=0.79); muscle area Z score were −0.9 (−3.2, −0.3) and −1.0 (−3.3, −0.9) (P=0.79). In the nine children who discontinued oral prednisolone at 6 months, volumetric BMD Z score were −1.2 (−2.8, −0.4) and −1.6 (−2.9, +0.5) (P=0.90); muscle area Z score were −2.5 (−4.3, −0.6) and −2.2 (−2.9, −0.5) (0.44). In the 12 children who showed progression in puberty, volumetric BMD Z score were −1.4 (−2.8, −0.4) and −1.2 (−2.6, 0.5) at baseline and 6 months (P=0.65); muscle area Z score were −1.6 (−3.4, −0.3) and −1.3 (−3.5, −0.5) (P=0.10).

Conclusion: Despite improvement in disease activity, reduction in oral steroid, progression in puberty and increase in plasma alkaline phosphatase following therapy with IFX, muscle bone assessment using pQCT in children with IBD over the short period did not show improvement.