TNF and inflammatory bowel disease: Lyles et al. performed a retrospective analysis of paediatric IBD, comparing proactive and reactive TDM with anti-TNF, and also found lower clinical remission and clinical and biological remission rates in proactive TDM than in our study at the end of the first year, at 59.2% vs. 84.21% and 42.7% vs. 63.16%, respectively [31].