Single-balloon Enteroscopy for Evaluation of Small Bowel Crohn Disease Strictures: Peripheral Blood Lymphocytes As a Risk Factor for Strictures

Few reports have focused on single-balloon enteroscopy (SBE) for evaluation of small bowel Crohn disease (CD) strictures. The aim of this study was to analyze the relationships between peripheral blood inflammatory markers and small bowel CD strictures observed by SBE.CD patients who underwent SBE between January 2016 and December 2020 were enrolled. The clinical characteristics and peripheral blood inflammatory markers were collected and analyzed to screen for predictive factors significantly associated with small bowel CD strictures.A total of 221 CD patients underwent SBE. The lymphocyte (LC) counts in peripheral blood were significantly lower in the active group (n=178) than in the inactive group (n=43) according to the simple endoscopic score for CD (SES-CD), P =0.011, and was correlated with the SES-CD ( r =-0.134, P =0.047). The LC levels were significantly lower in the stricture group (n=116) than in the nonstricture group (n=105) based on whether small bowel strictures developed, P =0.000, and LC was a risk factor for strictures in the multivariate analysis [hazard ratio (HR), 2.332; 95% CI, 1.102-4.937; P =0.027]. In the subgroup analysis, LC levels notably decreased after stricture aggravation ( P =0.000). Forty-seven patients who underwent small bowel resection underwent SBE at 6 to 12 months after surgery. The LC level was significantly lower in the postoperative patients with strictures ( P =0.025), and LC (HR, 4.444; 95% CI, 1.265-15.617; P =0.020) was a risk of postoperative strictures by univariate analysis, but the age at diagnosis (HR, 6.462; 95% CI, 1.272-22.560; P =0.022) was an independent risk factor by multivariate analysis.Peripheral blood LC levels were correlated with SES-CD and gradually decreased as the intestinal stricture increased in small bowel CD patients. The LC level was also significantly lower in the postoperative CD patients with strictures. The level of LC was a risk factor for small bowel strictures. These results suggest that peripheral blood LC could be a novel marker of small bowel CD strictures to guide CD diagnosis and therapy.