Inflammatory mesenteric fat detected by Intestinal ultrasound is correlated with poor long-term clinical outcomes in patients with Crohn's disease

Data on the correlation between inflammatory mesenteric fat (i-fat), detected by intestinal ultrasound (IUS), and the prognosis of Crohn's disease (CD) remains limited.To investigate the impact of IUS-detected i-fat on long-term clinical outcomes.We retrospectively enrolled 171 active CD patients who initiated infliximab. Clinical remission (CR), mucosal healing (MH) and transmural healing (TH) were assessed at week-14 and 1 year.Baseline i-fat was detected in 107 patients, while 64 without i-fat. At week-14 and 1 year, patients with i-fat showed lower rates of CR (61.7% vs. 87.5%; 62.3% vs. 86.7%), MH (20.6% vs. 46.9%; 38.6% vs. 65.0%) and TH (10.3% vs. 31.3%; 21.6% vs. 51.7%), compared to those without (all p<0.01). Multivariable analysis revealed that baseline i-fat was a negative predictor for CR (OR=0.212) and MH (OR=0.425) at week-14, and CR (OR=0.340) and TH (OR=0.364) at 1 year (all p<0.05). At week-14, 56 patients with baseline i-fat recovered to without i-fat. Patients with i-fat recovery had higher rates of CR (86.8% vs. 23.1%), MH (58.5% vs. 7.7%) and TH (34.0% vs. 2.6%) at 1 year than those with i-fat at week-14 (all p<0.001).IUS-detected i-fat correlated poor long-term clinical outcomes in CD with infliximab.