Early Intestinal Ultrasound Assessment Predicts Therapy Response: An Easy Tool for Clinical Decision-Making

Transmural healing (TH) has emerged as a therapeutic target in Crohn's disease (CD), providing a more comprehensive indicator of deep remission than mucosal healing alone. Intestinal ultrasound (IUS) is a noninvasive method for assessing TH, but its prognostic value remains insufficiently defined.

The aim of this prospective study was to evaluate whether early improvement in IUS parameters during biological therapy could predict TH at 12 months.

This is a prospective multicenter study enrolling CD patients initiating biological therapies. IUS and Doppler parameters were assessed at baseline, 3 months, and 12 months. Delta (Δ) represented the variation in ultrasound measurements between baseline and 3 months. TH was defined as normalization of bowel wall features and absence of hypervascularization.

A total of 142 CD patients were included. At 12 months, the TH rate was 19%, the IUS response rate was 44%. Patients achieving TH showed a significantly greater ΔBWT than nonresponders (P = .0004). On ROC analysis, a ΔBWT reduction of 1.25 mm predicted TH with 73% sensitivity and 61% specificity. IUS responders had a significantly greater ΔBWT than nonresponders (P < .0001), with the same threshold predicting response with 83% sensitivity and 57% specificity. Notably, the combination of ΔBWT and Limberg score improvement was strongly associated with both TH (OR 13.26; P < .0001) and IUS response (OR 20.9; P < .0001) at 12 months.

Early reduction in BWT, especially when combined with Limberg score, is a strong predictor of TH and IUS response at 12 months, supporting the use of early IUS monitoring in clinical practice.