Patients with Crohn’s disease commonly develop ileal and less commonly colonic strictures, containing various degrees of inflammation and fibrosis. While predominantly inflammatory strictures may benefit from a medical anti-inflammatory treatment, predominantly fibrotic strictures currently require endoscopic balloon dilation or surgery. Therefore, differentiation of the main components of a stricturing lesion is key for defining the therapeutic management. The role of endoscopy to diagnose the nature of strictures is limited by the superficial inspection of the intestinal mucosa, the lack of depth of mucosal biopsies and by the risk of sampling error due to a heterogeneous distribution of inflammation and fibrosis within a stricturing lesion. These limitations may be in part overcome by cross-sectional imaging techniques such as ultrasound, CT and MRI, allowing for a full thickness evaluation of the bowel wall and associated abnormalities. This systematic literature review provides a comprehensive summary of currently used radiologic definitions of strictures. It discusses, by assessing only manuscripts with histopathology as a gold standard, the accuracy for diagnosis of the respective modalities as well as their capability to characterise strictures in terms of inflammation and fibrosis. Definitions for strictures on cross-sectional imaging are heterogeneous; however, accuracy for stricture diagnosis is very high. Although conventional cross-sectional imaging techniques have been reported to distinguish inflammation from fibrosis and grade their severity, they are not sufficiently accurate for use in routine clinical practice. Finally, we present recent consensus recommendations and highlight experimental techniques that may overcome the limitations of current technologies.

Boras et al. demonstrate that Skap2, via interaction with WASp, regulates actin polymerization and binding of talin-1 and kindlin-3 to the β2 integrin, thereby being indispensable for β2 integrin activation and neutrophil recruitment.

SummaryBackgroundEvidence for endoscopic balloon dilation of small intestinal strictures in Crohn's disease (CD) using balloon‐assisted enteroscopy is scarce.AimTo evaluate endoscopic balloon dilation for the treatment of small intestinal CD strictures using balloon‐assisted enteroscopy.MethodsCitations in Embase, MEDLINE, and Cochrane were systematically reviewed. In a meta‐analysis of 18 studies with 463 patients and 1189 endoscopic balloon dilations, technical success was defined as the ability to dilate a stricture. Individual data were also obtained on 218 patients to identify outcome‐relevant risk factors.ResultsIn the pooled per‐study analysis, technical success rate of endoscopic balloon dilation was 94.9%, resulting in short‐term clinical efficacy in 82.3% of patients. Major complications occurred in 5.3% of patients. During follow‐up, 48.3% of patients reported symptom recurrence, 38.8% were re‐dilated and 27.4% proceeded to surgery. On the per‐patient‐based multivariable analysis, that patients with disease activity in the small intestine had lower short‐term clinical efficacy (odds ratio 0.32; 95% confidence interval 0.14‐0.73, P = 0.007). Patients with concomitant active disease in the small and/or large intestine had an increased risk to proceed toward surgery (hazard ratio 1.85; 95% confidence interval 1.09‐3.13, P = 0.02 and hazard ratio 1.77; 95% confidence interval 1.34‐2.34, P < 0.001).ConclusionsBalloon‐assisted enteroscopy for dilatation of CD‐associated small intestinal strictures has high short‐term technical and clinical efficacy and low complication rates. However, up to two‐thirds of patients need re‐dilation or surgery.

The life expectancy of unresectable hilar cholangiocellular carcinomas (CCCs) is very limited and endoscopic radiofrequency ablation (ERFA) of the biliary tract may prolong survival. Our single-center-study retrospectively analysed all CCC cases, in whom ERFAs of the biliary tract were performed between 2012 and 2017 and compared these to historical control cases who received the standard treatment of sole stent application. ERFA was performed in 32 patients with malignant biliary strictures that were mainly caused by Bismuth III and IV hilar CCCs (66%). 14 of these patients received repeated ERFAs, for an overall performance of 54 ERFAs. Stents were applied after examination of all patients (100%). Adverse events occurred in 18.5% of examinations. Case-control analysis revealed that the survival time of cases with unresectable Bismuth type III and IV hilar CCCs (n = 20) treated with combined ERFA and stent application significantly increased compared to controls (n = 22) treated with sole stent application (342 +/− 57 vs. 221 +/− 26 days; p = 0.046). In conclusion, ERFA therapy significantly prolonged survival in patients with unresectable Bismuth type III and IV hilar CCC. As an effective and safe method, ERFA should be considered as a palliative treatment for all these patients.