Comparison Between Bowel Ultrasound-based Treat to Target Versus Routine Treat to Target Strategies in Ulcerative Colitis

UC (UC) is a chronic, relapsing and destructive inflammatory disorder of the colon which can lead to organ damage and impair quality of life.

Consensus guidelines recommend to go beyond resolution of clinical symptoms and achieve endoscopic remission. This long-term treatment goal in UC is commonly defined by a Mayo endoscopic subscore < 13, and is associated with prolonged clinical remission, lower rates of hospitalization and lower rates of colectomy. However, colonoscopy is an invasive and expensive procedure, unpleasant to patients, not without risks, especially during severe flares. Moreover, CS is time-consuming and expensive for the Healthcare System.

Clinical symptoms correlate well with endoscopic findings, and their improvement together to normalization of FC, are currently considered the short-term and intermediate-term targets to achieve. However, while asymptomatic patients with FC < 50 mcg/g have < 5% probability to have endoscopic lesions, and conversely patients with evident rectal bleeding and persistent increased stool frequency (> 3 stools above baseline) with FC > 250 mcg/g have less than 5% chance to have endoscopic remission, in patients in the intermediate scenarios with stool frequency score (SFS) 2 or 3 or rectal bleeding score (RBS) > 0, with FC values between 50 and 250 mcg/g, the uncertainty increases and CS should not be avoided.

Bowel US is a well-tolerated, non-invasive, patient friendly, cheap, easy-to-use tool to manage UC patients in clinical practice8. In addition, its ability to be performed as point-of-care bowel US may drastically change frequency of the assessment of treatment response, speeding the clinical decision-making process9. Recently, the investigators developed and externally validated non-invasive ultrasonography based criteria [Milan ultrasound criteria (MUC)] to assess and grade endoscopic activity in UC10,11. The investigators also confirmed that a MUC score > 6.2 is a valid cut-off to discriminate endoscopic activity, defined by a Mayo endoscopic subscore > 1 Bowel US is a well-tolerated, non-invasive, patient friendly, cheap, easy-to-use tool to manage UC patients in clinical practice. In addition, its ability to be performed as point-of-care bowel US may drastically change frequency of the assessment of treatment response, speeding the clinical decision-making process. Recently, the investigators developed and externally validated non-invasive ultrasonography based criteria [Milan ultrasound criteria (MUC)] to assess and grade endoscopic activity in UC14,15. The investigators also confirmed that a MUC score > 6.2 is a valid cut-off to discriminate endoscopic activity, defined by a Mayo endoscopic subscore > 1.