Difficulty in diagnosing inflammatory bowel disease in the small intestine

Posted by Doctor Mai Vien Phuong - Department of Medical Examination & Internal Medicine - Vinmec Central Park International General Hospital

Inflammatory bowel disease (IBD) represents a group of chronic inflammatory disorders involving the colon, small intestine (SB) and the entire gastrointestinal tract and includes Crohn's disease (Crohn's disease), ulcerative colitis (Crohn's disease), and ulcerative colitis (Crohn's disease). UC) and unclassified entities. Crohn's disease Crohn's disease is an immune-mediated chronic inflammatory disease that usually involves the ileum and terminal colon, but at the time of diagnosis it may be confined to the small intestine, as is seen in about 30% of patients. patients with Crohn's disease, especially younger patients.

Small bowel Crohn's disease alone can be difficult to diagnose and manage for a number of reasons. First, small bowel Crohn's disease alone is more difficult to access with endoscopy, making it easier to miss the diagnosis of small bowel Crohn's disease alone with conventional endoscopy, which contributes to the delay in diagnosis as observed in many patients with Crohn's disease. . Second, small bowel ulcers caused by infections (such as tuberculosis) or medications can sometimes be difficult to distinguish from Crohn's disease. Third, compared with other phenotypes, small bowel Crohn's disease alone is associated with an increased risk of recurrence and serious development. Fourth, small bowel cancer associated with small bowel Crohn's disease is a rare but difficult problem because only a small number of these cases are diagnosed preoperatively and at an early stage. Finally, in the pediatric population, small bowel Crohn's disease alone is of particular clinical relevance because of its negative impact on pubertal growth and development. Therefore, objective evaluation of the SB mucosa is essential in distinguishing Crohn's disease from other bowel diseases for treatment decision making and follow-up planning.
For many years, examining the small intestine has been a challenge because of its anatomical nature, location and relative torture. The advent of cross-sectional imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI), computed tomography of the bowel/gastrointestinal tract, and SB ultrasound, has enhanced pathological assessment. small intestine with high accuracy in assessing whole-mucosal and intraluminal disease, but subtle mucosal changes can still be missed.

Capsule endoscopy (CE) and assistive small bowel endoscopy (assisted small bowel endoscopy) have greatly expanded the diagnostic capabilities of small bowel diseases. Capsule endoscopy provides a noninvasive test for visualization of the entire small intestinal mucosa, which can aid in the diagnosis of small bowel Crohn's disease and monitor response to treatment. The main limitations of Capsule Endoscopy in IBD patients are low specificity, lack of therapeutic potential, and inability to perform biopsies.
Device-assisted small bowel endoscopy allows histological confirmation when other modalities, such as traditional endoscopy, capsule endoscopy and cross-sectional imaging, are inconclusive and permit interventions treatments, such as balloon dilation, intraoral steroid injections, capsule removal, and more recently stenting through the stricture.

Regarding the use of device-assisted small bowel endoscopy for diagnostic purposes in adult patients, recent European Gastroenterology guidelines recommend its use for: (1) Patients with endoscopy normal stomach and colon and suspected Crohn's disease on MRI or capsule endoscopy, if necessary to confirm the diagnosis by endoscopy and histology; and (2) The patient required endoscopic intervention to dilate the small bowel stricture.
According to studies, the diagnostic results of device-assisted small bowel endoscopy in adult patients with suspected Crohn's disease and known Crohn's disease are 27%-79% and 53%-87%, respectively. and higher if indicated for device-assisted small bowel endoscopy based on previous small bowel evaluation that can identify suspected lesions and guide the selection of a pre-oral route for small bowel exploration. or anterior anal canal. Meanwhile, the diagnostic efficiency of device-assisted small bowel endoscopy is strongly reduced when indicated based on non-specific abdominal symptoms alone. Similarly, the agreement rate between imaging and assistive small bowel endoscopy was higher in patients with diagnosed Crohn's disease than in patients with suspected Crohn's disease (75.6% vs. 36.4%). In published studies, a significant impact of assistive small bowel endoscopy on patient management, ranging from 17% to 82%, was reported with persistent clinical improvement. persistence reached 83% after a mean follow-up of 13 months in Mensink et al.'s study.

References
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