Predictors of infliximab refractory intestinal Behçet's syndrome: A retrospective cohort study from the Shanghai Behçet's syndrome database

Objectives: This retrospective cohort study aimed to find out predictors and early biomarkers of Infliximab (IFX) refractory intestinal Behçet's syndrome (intestinal BS).

Methods: We collected the baseline clinical characteristics, laboratory parameters, and concomitant therapies of intestinal BS patients treated by IFX from the Shanghai Behçet's syndrome database. After 1 year IFX therapy, intestinal BS patients with non-mucosal healing (NMH, intestinal ulcers detected by colonoscopy) and/or no clinical remission [NCR, scores of the disease activity index for intestinal Behçet's disease (DAIBD) ≥20] were defined as IFX refractory intestinal BS. Multivariate logistic regression analysis was performed to evaluate the predictors for NMH and NCR in IFX refractory intestinal BS.

Results: In 85 intestinal BS patients, NMH was identified in 29 (34.12%) patients, and NCR was confirmed in 20 (23.53%) patients. Erythrocyte sedimentation rate (ESR; ≥24 mm/h) and free triiodothyronine (fT3; ≤3.3pmol/L) were the independent risk factors of NMH in IFX refractory intestinal BS. Drinking alcohol and the fT3/free thyroxine ratio (fT3/fT4; ≤0.24) were independent risk factors, and thalidomide was an independent protective factor, for NCR in intestinal BS patients treated by IFX.

Conclusion: This study may be applicable for adjusting the therapeutic strategy and sidestepping unnecessary exposure to IFX in intestinal BS patients. Routine assessments of ESR, fT3, and fT3/fT4 ratio are helpful to identify high-risk individuals of IFX refractory intestinal BS. Thalidomide is suggested to be a concomitant therapy with IFX for intestinal BS patients.