Endoscopic Stent Treatment for Crohn’s Disease

Introduction

Crohn's disease (CD) is an inflammatory disorder that can be classified as stricturing, penetrating and non-stricturing, non-penetrating behavior based on the Montreal Classification. A stricture is an abnormal area of narrowing in the intestinal lumen and develops progressively over years with the growth of fibrotic tissue in a chronic inflammatory background. Stricturing events increase with the disease duration ranging from subtle to complete obstruction and stenosis. It is seen in 30%–35% of patients within 10 years of diagnosis of CD and approximately 70%–80% of patients will eventually require surgery by 20 years. Strictures are considered clinically relevant when there is a significant narrowing of the lumen with prestenotic dilation and obstructive symptoms. Diagnosis is made by imaging studies or endoscopy.

In 80% of the patients with CD, there is endoscopic evidence of recurrence at 1 year. More than 50% of the patients would need a repeat surgery after 15 years. Over 40% have a recurrence of obstructive symptoms after 4 years and probably would require severe surgical procedures in the long term.

Specific treatment is required only for symptomatic strictures irrespective of accompanying dilation on upstream imaging. Currently, the recommended treatment for CD-associated short strictures, less than 4–5 cm, is endoscopic balloon dilation (EBD) in combination with optimum medical therapy for the active luminal disease. It is a safe and effective alternative to surgery with an approximately 2% incidence of severe adverse events such as perforation and an overall success rate ranging from 44% to 67%. However, 50%–75% of patients experience a recurrence of the stricture within 1 year of EBD. In these patients, self-expanding metal stents (SEMS) would be a minimally invasive alternative to the repeat EBD or surgery.

SEMS have so far shown promising results but has also been reported with a high rate of adverse events. Removal of the stent within the first month of deployment is required to avoid intestinal impaction. Biodegradable stents have been recently introduced to overcome these drawbacks. Their initial case reports and case series have been reassuring with acceptable clinical results and no mucosal growth. Some of the results of these studies have been criticized because they included patients naive to EBD.

We will discuss the efficacy and safety of metallic and biodegradable stents and to discuss the types of the stents, their indications, and their clinical utility in CD.