Description of the condition
Crohn’s disease (CD) is a chronic inflammatory disease of the GI tract of unknown cause. The course of CD is characterized by periods of remissions and relapses. Traditionally, treatment has been aimed at inducing and maintaining remission of symptoms. With the recent recognition of mucosal healing as an important outcome, treatment is now focused on reducing intestinal inflammation, preventing complications, and decreasing the need for surgery. Despite modern immunosuppressive regimens many patients require treatment for stricturing disease (Himal 1981; Rutgeerts 1990; Hanauer 2004; Louis 2012).
Stricture formation defined as a constant, localized narrowing of the large or small bowel, is a common complication of CD. Strictures are often only a few centimetres in length but may be considerably longer. No drug therapy currently exists to treat fibrotic strictures. Accordingly, they usually require surgical resection or strictureplasty. However, surgery does not cure Crohn's disease. Within one year of surgical resection of all visible disease, the endoscopic recurrence rate may be as high as 90% (Rutgeerts 1984; Tytgat 1988; Olaison 1992; Borley 2002; Onali 2009). Repeated operations carry the risk of both important mortality and morbidity such as short-bowel syndrome.
Description of the intervention
Endoscopic treatment of strictures, such as balloon dilatation and stent placement have been used as an alternative to surgery (Williams 1991; Foster 2008; Despott 2009; Stiencker 2009; Thienpont 2010). These techniques can be used on their own or in conjunction with adjunctive medical therapies such as injection of corticosteroids. Endoscopic balloon dilatation (EBD) is performed during a regular endoscopic procedure (i.e. colonoscopy, gastroscopy, push-enteroscopy, double- or single-balloon enteroscopy) using a balloon catheter of up to 25 mm in diameter (Pohl 2007; Hirai 2010). The balloon is filled with water under visual control, and insufflated by a multi-step inflation with usually two minutes of inflation time at the maximal diameter (12 to 25 mm). Passage of the endoscope through the dilated stricture is then attempted. An additional dilatation with inflation of the balloon is performed if the first dilatation does not allow the passage of the endoscope through the strictured area. In some instances stents including self-expandable metallic stents (SEMS) are inserted endoscopically. Adjunctive techniques such as local injections of corticosteroids or balloon dilatation may be also used before or during the SEMS placement.
How the intervention might work
Balloon dilatation mechanically disrupts scar tissue and increases the luminal diameter. Adjunctive anti-inflammatory therapy such as intramural injection of corticosteroids is intended to blunt an inflammatory response to the tissue injury that results from dilatation and prevent re-stricturing. Although the available data indicate that endoscopic treatment relieves obstructive symptoms resulting from strictures very few randomized controlled trials (RCTs) exist (Williams 1991; Couckuyt 1995; Karstensen 2012).
The technical success rate of endoscopic intervention in Crohn's disease patients with strictures is reported as 84 to 100% while the long-term success rate based on relief of obstructive symptoms varies from 41 to 100% (Couckuyt 1995; Thomas-Gibson 2003; Singh 2005; Lavy 2007; Mueller 2010). Most of the patients who are described in these studies (up to 100%) have previously undergone surgery (Sabate 2003; Thomas-Gibson 2003; Nomura 2006; Scimeca 2011; Nanda 2012). Patients who undergo endoscopic treatment may have quiescent disease or active inflammation. Most strictures are located at the area of anastomoses. Major complications such as perforation (requiring surgery) or bleeding (requiring surgery or blood transfusion) occur in 2 to 5% of cases (Ferlitsch 2006; Stiencker 2009; Gustavsson 2012; Karstensen 2012). No deaths have been reported in the literature. Although the results of endoscopic treatment are encouraging, surgery is eventually required in up to 38% of patients because of persistent obstructive symptoms. However, multiple studies (Blomberg 1991; Williams 1991; Hoffmann 2008; Stiencker 2009; Karstensen 2012; Nanda 2012) have reported long-term benefit after endoscopic intervention in at least two thirds of patients with Crohn's strictures. Active inflammation at the site of the stricture and medical treatment during or following endoscopic treatment does not affect long-term outcomes of endoscopic treatment (East 2007; Thienpont 2010; Nanda 2012). The long-term data on efficacy of intralesional steroid injection after EBD in Crohn's disease with stricture are inconsistent (Ramboer 1995; Lavy 2007; East 2007; Di Nardo 2010). All studies that have been reported in the literature conclude that endoscopic therapy of strictures is an effective and safe alternative to surgery.
Why it is important to do this review
The development of a stricture in a patient with Crohn's disease is an important complication that can negatively affect quality of life. It is estimated that approximately 50% of patients with Crohn's disease affecting the ileum have stricturing disease. Bowel obstruction due to stricture may result in perforation, sepsis and death. Most patients with stricturing Crohn's disease will require surgery, usually within 7 to 10 years of diagnosis. Some patients will require multiple surgeries. A preliminary review of the literature shows that endoscopic treatment of Crohn's disease strictures may relieve symptoms without the need for surgery. Therefore, endoscopic treatment may have a substantial benefit. A systematic review of the literature is warranted to define the efficacy and safety of endoscopic interventions (i.e. balloon dilatation, intramural corticosteroid injection and stent placement) for the management of Crohn's disease strictures in comparison to surgical therapy (i.e. strictureplasty or small bowel resection).