The Colon Wall Thickness Measured Using Transabdominal Ultrasonography Is Useful for Detecting Mucosal Inflammation in Ulcerative Colitis

Application Value of Endoscopic Ultrasonography in Diagnosis and Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease refers to a group of non-specific inflammatory illnesses affecting the gastrointestinal tract. According to pathogenic characteristics, it is divided into Ulcerative colitis and Crohn's disease. The exact cause and pathogenic mechanism of these disorders are not yet fully understood. In addition, there is currently no definitive diagnostic method for inflammatory bowel disease, which mainly depends on clinical symptoms, blood testing, imaging investigations, and endoscopic examination, which includes histology. Endoscopic Ultrasonography is a digestive tract examination technique that combines endoscopy and ultrasound. Compared to conventional endoscopy, it can visualize surface and deep lesions of the gastrointestinal wall, as well as provide information on the characteristics of the surrounding layers and nearby lymph nodes. Due to these advantages, Endoscopic Ultrasonography has played a significant role in the evaluation of inflammatory bowel disease in recent years. Through this work, we aim to identify the applications of this method in the case of patients with inflammatory bowel disease.

Four intestinal ultrasound scores and bowel wall thickness alone correlated well with pediatric ulcerative colitis disease activity

OBJECTIVES

Intestinal ultrasound (IUS) is a noninvasive tool in ulcerative colitis (UC), but scoring systems have mostly been developed for adults, Crohn's disease, and flaring UC. Our aim was to evaluate the performance of bowel wall thickness (BWT) and four IUS scores in pediatric patients with newly diagnosed UC.

METHODS

Patients <18 years old with suspected UC were prospectively enrolled. Baseline IUS was done, and ulcerative colitis intestinal ultrasound score (UC-IUS), Milan criteria, simple pediatric activity ultrasound score (SPAUSS), and Civatelli Index were calculated. Mayo endoscopic segment subscore, pediatric ulcerative colitis activity index (PUCAI), and biomarkers were correlated with IUS using nonparametric and receiver operating characteristic analyses.

RESULTS

Fifty-two patients (56% male, median age 13.9 years, interquartile range [IQR] 11.2-16.3) with 206 colon segments were included. Patients who needed hospitalization (n = 27/52) had significantly worse IUS (BWT and all scores) compared to those not hospitalized. For all patients, IUS scores and BWT significantly correlated with baseline endoscopic, clinical, and biochemical disease activity (p = 0.32-0.67, p < 0.05). BWT (τb = 0.53), UC-IUS (τb = 0.55), and Milan (τb = 0.52) had the strongest endoscopic correlations. For differentiating between endoscopic disease severity, BWT, UC-IUS, and Milan, had the highest areas under the curve (0.89-0.93). Using BWT alone, a thinner cut-off had improved sensitivity while maintaining high specificity: ≥2.5 mm for moderate/severe endoscopic inflammation (sensitivity 66%; specificity 94%) and ≥3.5 mm for severe endoscopic inflammation (sensitivity 92%; specificity 86%).

CONCLUSIONS

BWT and all four IUS scores correlated well with endoscopic, clinical, and biochemical disease activity, and was another useful marker of severity in identifying patients needing hospitalization. Pediatric patients needed a thinner BWT cut-off, which should be accounted for when developing pediatric-specific scores. BWT alone may be just as clinically useful as composite US scores.

Novelties and Perspectives of Intestinal Ultrasound in the Personalised Management of Patients with Inflammatory Bowel Diseases-A Systematic Review

Inflammatory bowel diseases (IBDs) affect over 4.9 million individuals worldwide. Colonoscopy (CS) is the gold-standard technique for diagnosis. The remissive-recurrent pattern of evolution raises the need for non-invasive techniques to monitor disease activity. This review aims to present the advantages of intestinal ultrasound (IUS) in managing IBDs. Our search was conducted on the PubMed, Embase, and Cochrane (CENTRAL) databases, selecting original studies comparing IUS with other imaging and invasive monitoring methods. Our search yielded 8654 results, of which 107 met the inclusion criteria. Increased bowel wall thickness (BWT) and colour Doppler signal (CDS) are discriminative for disease activity. IUS can predict disease outcomes and detect response to treatment or postoperative recurrence. Contrast-enhanced ultrasound (CEUS) and elastography help differentiate fibrotic from inflammatory stenoses. The difficult rectal assessment limits the use of IUS in ulcerative colitis (UC). Transmural healing may develop as a therapeutic target as it is associated with better outcomes. Patients are compliant with this technique, and its results correlate well with CS and other imaging methods. In conclusion, IUS proves to be essential in assessing IBD activity and treatment response, predicting outcomes and detecting complications. CEUS and elastography are researched to improve the diagnostic values of IUS.

Single measurement of bowel wall thickness using intestinal ultrasonography in children with ulcerative colitis

BACKGROUND

Endoscopic monitoring of disease activity in patients with ulcerative colitis (UC) is important. However, frequent colonoscopic examinations are difficult to perform because of their invasiveness, especially in children. Bowel wall thickness (BWT) measurement using intestinal ultrasonography and fecal calprotectin (FC) measurement are useful noninvasive evaluation methods.

METHODS

We retrospectively analyzed BWT and FC levels and evaluated the Mayo endoscopic subscore (MES) using colonoscopy in pediatric patients with UC during the same period. The BWT was evaluated using the maximum BWT (mBWT), which was the maximum value of each colonic BWT; the sum of BWT (sBWT), which was the sum of each colonic BWT; and the sum of the adjusted BWT (saBWT), which was corrected using sBWT.

RESULTS

In 54 procedures from 40 patients, FC, mBWT, sBWT, and saBWT were significantly different between MES 0-1 and MES 2. The agreement between BWT and MES 2 was 193 out of 216 segments (89.4%). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FC were 68.8%, 84.2%, 64.7%, 86.5%, and 79.6% respectively, while those of saBWT were 81.2%, 89.5%, 76.5%, 91.9%, 87.0%, respectively.

CONCLUSIONS

BWT in each colonic segment, particularly saBWT, was more useful than FC for detecting moderate colonic inflammation (MES 2) in pediatric patients with UC. Therefore, intestinal ultrasonography may be helpful in the less invasive management of pediatric patients with UC.

Diagnostic accuracy of bowel ultrasonography in patients with inflammatory bowel disease: a systematic review and meta-analysis

Background

Bowel ultrasonography (BUS) is emerging as a promising noninvasive tool for assessing disease activity in inflammatory bowel disease (IBD) patients. We evaluated the diagnostic accuracy of BUS in IBD patients against the gold standard diagnostic method, standard colonoscopy.

Methods

Major databases were searched from inception to May 2023 for studies on BUS diagnostic accuracy in IBD. Outcomes of interest were pooled sensitivity, specificity, positive (PPV), and negative (NPV) predictive values. Endoscopic confirmation served as ground truth. Standard meta-analysis methods with a random-effects model and I2 statistics were applied. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

Results

Twenty studies (1094 patients) were included in the final analysis. The majority (75%) of studies considered bowel wall thickness >3 mm as abnormal. Endoscopic evaluation was performed between days 3 and 180. The pooled diagnostic accuracy of BUS in IBD was 66% (95% confidence interval [CI] 58-72%; I2=78%), sensitivity was 88.6% (95%CI 85-91%; I2=77%), and specificity 86% (95%CI 81-90%; I2=95%). PPV and NPV were 94% (95%CI 93-96%; I2=25%) and 74% (95%CI 66-80%; I2=95%), respectively. On subgroup analysis, small-intestine contrast-enhanced ultrasonography (SICUS) demonstrated high sensitivity (97%, 95%CI 91-99%; I2=83%), whereas BUS exhibited high specificity (94%, 95%CI 92-96%; I2=0%) and NPV (76%, 95%CI 68-83%; I2=80.9%). Meta-regression revealed a significant relation between side-to-side anastomosis and BUS specificity (P=0.02) and NPV (P=0.004).

Conclusion

The high diagnostic accuracy of BUS in detecting bowel wall inflammation suggests utilizing regular BUS as the primary modality, with subsequent consideration of SICUS if clinically warranted.