Terminal Ileum Intubation: A New Standard for Colonoscopy

A recent systematic review has concluded that terminal ileum intubation should be adopted as standard practice during colonoscopy for all patients, with biopsies recommended under specific conditions. The review aimed to address a lack of consensus regarding when to perform ileoscopy and biopsy, identifying terminal ileum intubation as crucial for a complete diagnostic process.

Background

Prior to this review, there was no definitive consensus regarding the routine performance of terminal ileum (TI) intubation and subsequent biopsy during colonoscopy procedures. Terminal ileum intubation is a step often undertaken to assess the ileum and collect biopsies for diagnostic purposes.

Methodology

A systematic review was conducted to evaluate the necessity of routine terminal ileum intubation and biopsy. Searches were performed across PubMed, EMBASE, Cochrane Library, and Science Citation Index (via Web of Science). The studies included in the analysis were published between January 1, 1971, and October 1, 2025, and reported on terminal ileum intubation and biopsy during colonoscopy. Case reports, letters, reviews, and animal studies were excluded.

The primary outcomes assessed by the review included:

• The diagnostic yield of terminal ileum intubation.
• The rate at which terminal ileum intubation necessitated a change in patient management.

Key Findings

The analysis encompassed 36 studies that met the inclusion criteria, providing robust data on terminal ileum intubation. The review's findings indicated:

• Diagnostic Yield and Management Changes: Both the subtotal diagnostic yield and the rate of necessary management changes were found to be higher in selected patient groups compared to unselected patients.

  • Subtotal diagnostic yield: 5.1% in selected patients versus 2.5% in unselected patients.
  • Rate of necessary management changes: 1.5% in selected patients versus 0.4% in unselected patients.

• Indications with Higher Diagnostic Yield: Diagnostic yield was significantly more frequent for specific conditions, highlighting targeted assessment benefits:

  • Inflammatory Bowel Disease (IBD): 26.7%
  • Anemia: 16.1%
  • Abdominal pain: 14.9%
  • Chronic diarrhea: 12.4%
  • Other indications: 3.2%

• Ileal Histopathology with Normal Endoscopic Appearance: The yield of ileal histopathology, even when the endoscopic appearance was normal, was found to be low, recording 3.5% in unselected patients and 2.4% in selected patients.

Recommendations

Based on these findings, the systematic review identified terminal ileum intubation as the "gold standard" for completing a colonoscopy and considered it essential in the diagnostic process.

The study recommended the following practices:

• Terminal ileum intubation should be adopted as standard practice and attempted in all patients undergoing colonoscopy, accompanied by photodocumentation.
• Biopsies should be obtained in cases presenting with abnormal mucosal findings or specific "red-flag" symptoms, including diarrhea, suspected Inflammatory Bowel Disease (IBD), abdominal pain, or anemia.