[Utility of abdominal ultrasonography in the management of ulcerative colitis:proposal of a new scoring system].

Abstract

In the management of ulcerative colitis (UC), colonoscopy (CS) is considered essential for diagnosis;however, its invasiveness poses a challenge. Conversely, recent advancements in ultrasound diagnostic devices have improved imaging quality for the digestive tract, rendering them valuable in UC management. Therefore, this study aimed to elucidate the correlation between abdominal ultrasonography (AUS) and CS in assessing UC activity. The indices adopted for UC evaluation using AUS were as follows:1) bowel wall stratification, 2) bowel wall thickness, 3) bowel wall flow at power Doppler, 4) presence of increased brightness of inflammatory fat, and 5) presence of mesenteric lymph node swelling greater than 5mm. Subsequently, we developed a new AUS index for UC, termed the UCUS score, which comprises the aforementioned five indices. Finally, we compared the UCUS score with representative endoscopic indices, the Mayo endoscopic sub-score, and the Ulcerative Colitis Endoscopic Index of Severity. The results demonstrated that our proposed UCUS score better reflected disease activity than individual items assessed separately. ROC curve analysis revealed a UCUS score cutoff of 3 points. Therefore, a UCUS score of ≥3 points indicates the need for further examination with CS. Conversely, a score below 3 points suggests low disease activity, and in situations when evaluating treatment effectiveness, AUS could potentially substitute for CS. We believe that the UCUS score is an important source of information to understand the patient's condition and to motivate the patient to undergo endoscopy.