Bowel wall thickness (BWT) as detected by intestinal ultrasound is an important predictor for endoscopy-detected treatment response among patients with ulcerative colitis (UC), according to study findings published in Gastroenterology.
Patients (N=30) with moderate to severe UC who were starting tofacitinib treatment were enrolled at the Amsterdam University Medical Center from 2018 to 2020 for the longitudinal prospective study. Data collected by intestinal ultrasound at baseline and week 8 of therapy were compared with endoscopy findings. Remission was defined as an endoscopic Mayo score (EMS) of 0, improvement as EMS of 1 or lower, and response as a decrease in an EMS score of 1 or higher.
The patient population comprised 60% women; had a median age of 35.5 (IQR, 27-53) years; had a median UC disease duration of 78 (IQR, 56-135) months previously; 57% had left-sided UC; 50% were using concomitant corticosteroids; 33% were using aminosalicates; 30% were biological therapy-naïve; and simple clinical colitis activity index (SCCAI) score was 9.50 (IQR, 6.50-11) points at baseline.
At week 8, 11% of patients had complete endoscopic remission, 23% histological remission, and 55% treatment response.
Correlations between BWT and EMS were observed in the sigmoid colon (r, 0.73; P <.0001) and descending colon (r, 0.76; P <.0001), BWT and ulcerative colitis endoscopic index of severity (UCEIS) in the sigmoid colon (r, 0.73; P <.0001) and descending colon (r, 0.74; P <.0001), and BWT and Robarts Histopathology Index (RHI) in the sigmoid colon (r, 0.49; P =.002).
Among patients with endoscopic improvement, median BWT in the sigmoid colon was significantly lower at week 8 (median, 1.8 vs 4.5 mm; P <.0001) compared with patients who did not have improvement, respectively. Similar trends were observed for the cohort in remission and with treatment response.
An area under the receiver operating characteristic curve (AUROC) analysis found a BWT cutoff for predicting endoscopic remission of 2.8 mm in the sigmoid colon (AUROC, 0.87; sensitivity, 73%; specificity, 100%; P =.006). A cutoff of 3.9 mm predicted endoscopic improvement (AUROC, 0.92; sensitivity, 81%; specificity, 100%; P <.0001) and a BWT decrease of 32% predicted endoscopic response (AUROC, 0.87; sensitivity, 71%; specificity, 90%; P =.002).
In the sigmoid colon, a BWT of more than 2.8 mm associated with no endoscopic remission (odds ratio [OR], 2.0; P =.002), of more than 3.9 mm with no endoscopic improvement (OR, 5.00; P <.0001), and a decrease of 32% with endoscopic response (OR, 21.60; P =.009).
Study limitations include using only one mode of action in the cohort, which may not be generalizable to other anti-inflammatory drugs; assessing endoscopic treatment response at the early time period of 8 weeks; and the inability to test multiple intestinal ultrasound parameters.
“We have demonstrated that IUS [intestinal ultrasound], and in particular BWT as a single most important parameter, is highly accurate in identifying segmental endoscopic remission, endoscopic improvement and response when compared to globally utilized endoscopic scoring indices, and it is even able to detect microscopic treatment response in patients [with] UC,” the study authors noted.
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
de Voogd F, van Wassenaer EA, Mookhoek A, et al. Intestinal ultrasound is accurate to determine endoscopic response and remission in patients with moderate to severe ulcerative colitis: a longitudinal prospective cohort study. Gastroenterology. Published online August 24, 2022. doi:10.1053/j.gastro.2022.08.038