Transrectal Ultrasound in the Diagnosis and Management of Inflammatory Bowel Disease

Background and Study Aims: To aim of the present study was to determine the value of transrectal ultrasonography (TRUS) in the assessment of disease activity in ulcerative colitis patients, and in differentiating between mucosal inflammation and transmural inflammation.

Patients and Methods: TRUS examinations were used to study 30 control individuals and 76 patients with inflammatory bowel disease, including 50 cases of ulcerative colitis and 26 of Crohn's disease. A rigid linear endorectal probe was used to examine the rectal wall.

Results: In the 30 control individuals, the rectal wall showed five layers, with a mean total diameter of 2.6 mm. There were significant differences between patients with quiescent ulcerative colitis, active ulcerative colitis, and control individuals with regard to the total rectal wall thickness (P < 0.001), submucosal thickness (P < 0.001) and mucosal thickness (P < 0.001). UsingCARET cut-off values, differentiation between active ulcerative colitis and remission ulcerative colitis was found to be 100 % specific and 73 % sensitive for submucosal thicknesses. TRUS revealed a 100 % specificity in differentiating between remission ulcerative colitis and control cases based on the total rectal wall thickness, submucosal, and mucosal thicknesses. In the differential diagnosis of active and remission ulcerative colitis, an increase in submucosal wall thickness and the existence of arterial and venous capillary flow in the submucosa were found to be specific and more sensitive than the other parameters. TRUS examination revealed transmural inflammation in 21 of the 26 Crohn's disease patients, and mucosal inflammation in all 50 of the ulcerative colitis patients.

Conclusion: TRUS is a reliable and easy method of assessing ulcerative colitis activity and differentiating between rectal diseases.