TREM1 and Crohn disease: The results of the current study are consistent with those of both the Personalising Anti-TNF Therapy in Crohn’s disease study of patients with CD [NCT03088449]17 and a small study in 33 children with IBD, in which baseline TREM-1 whole blood gene expression did not predict response to either adalimumab or infliximab.11 However, they contrast with the findings of other studies where TREM-1 appeared to be predictive of clinical and/or endoscopic outcomes in patients with IBD, albeit with opposing signals for low vs high baseline TREM-1 expression levels linked to response.7,8,10