Do We Need Activity Scores or Simply Clear Criteria for Intestinal Ultrasound in Ulcerative Colitis?

Insights into the role of gastrointestinal ultrasound in ulcerative colitis

Endoscopic evaluation with histological sampling is the gold standard for the diagnosis and follow-up of patients with inflammatory bowel disease (IBD), but in the past few years, gastrointestinal ultrasound (GIUS) has been gaining ground. Due to the transmural nature of inflammation in Crohn's disease, GIUS has been mainly applied in this context. However, GIUS is now being reported to be accurate also for ulcerative colitis (UC). This review summarizes current knowledge on the use of GIUS in UC, with a focus on clinical practice. The review covers topics such as GIUS parameters, especially bowel wall thickness; the use of GIUS in assessing disease extent and in monitoring disease activity; GIUS indexes and scores; and the combination of GIUS with transperineal ultrasound for a better assessment of the rectum. With the always growing body of evidence supporting the accuracy of GIUS in UC, this diagnostic imaging modality can be expected to play a bigger role in disease flare evaluation, early treatment monitoring, and acute severe disease management.

A Reliability Study: Strong Inter-Observer Agreement of an Expert Panel for Intestinal Ultrasound in Ulcerative Colitis

BACKGROUND

Intestinal ultrasound [IUS] is a promising and non-invasive cross-sectional imaging modality in the diagnosis and monitoring of ulcerative colitis [UC]. Unlike endoscopy, where standardized scoring for evaluation of disease activity is widely used, scoring for UC with IUS is currently unavailable. Therefore, we conducted a study to assess the reliability of IUS in UC among expert sonographists in order to identify robust parameters.

METHODS

Thirty patients with both clinically active [25] and quiescent [five] UC were included. Six expert sonographers first agreed upon key IUS parameters and grading, including bowel wall thickness [BWT], colour Doppler signal [CDS], inflammatory fat [i-fat], loss of bowel wall stratification [BWS], loss of haustrations and presence of lymph nodes. Thirty video-recorded cases were blindly reviewed.

RESULTS

Inter-observer agreement was almost perfect for BWT (intra-class correlation coefficient [ICC]: 0.96) and substantial for CDS [κ = 0.63]. Agreement was moderate for presence of lymph nodes [κ = 0.41] and fair for presence of i-fat [κ = 0.36], BWS [κ = 0.24] and loss of haustrations [κ = 0.26]. Furthermore, there was substantial agreement for presence of disease activity on IUS [κ = 0.77] and almost perfect agreement for disease severity [ICC: 0.93]. Most individual parameters showed a strong association with IUS disease activity as measured by the six readers.

CONCLUSION

IUS is a reliable imaging modality to assess disease activity and severity in UC. Important individual parameters such as BWT and CDS are reliable and could be incorporated in a future UC scoring index. Standardized acquisition and assessment of UC utilizing IUS with established reliability is important to expand the use of IUS globally.

Intestinal ultrasound for monitoring therapeutic response in patients with ulcerative colitis: results from the TRUST&UC study

OBJECTIVE

Prospective evaluation of intestinal ultrasound (IUS) for disease monitoring of patients with ulcerative colitis (UC) in routine medical practice.

DESIGN

TRansabdominal Ultrasonography of the bowel in Subjects with IBD To monitor disease activity with UC (TRUST&UC) was a prospective, observational study at 42 German inflammatory bowel disease-specialised centres representing different care levels. Patients with a diagnosis of a proctosigmoiditis, left-sided colitis or pancolitis currently in clinical relapse (defined as Short Clinical Colitis Activity Index ≥5) were enrolled consecutively. Disease activity and vascularisation within the affected bowel wall areas were assessed by duplex/Colour Doppler ultrasonography.

RESULTS

At baseline, 88.5% (n=224) of the patients had an increased bowel wall thickness (BWT) in the descending or sigmoid colon. Even within the first 2 weeks of the study, the percentage of patients with an increased BWT in the sigmoid or descending colon decreased significantly (sigmoid colon 89.3%-38.6%; descending colon 83.0%-42.9%; p<0.001 each) and remained low at week 6 and 12 (sigmoid colon 35.4% and 32.0%; descending colon 43.4% and 37.6%; p<0.001 each). Normalisation of BWT and clinical response after 12 weeks of treatment showed a high correlation (90.5% of patients with normalised BWT had symptomatic response vs 9.5% without symptomatic response; p<0.001).

CONCLUSIONS

IUS may be preferred in general practice in a point-of-care setting for monitoring the disease course and for assessing short-term treatment response. Our findings give rise to the assumption that monitoring BWT alone has the potential to predict the therapeutic response, which has to be verified in future studies.

Bowel Ultrasound Scan Predicts Corticosteroid Failure in Children With Acute Severe Colitis

BACKGROUND AND OBJECTIVE

Acute severe colitis (ASC) is a potentially life-threatening event. Optimal timing for second-line treatment in children is mainly based on the clinical score Pediatric Ulcerative Colitis Activity Index. The aim of our study was to evaluate the potential role of bowel ultrasound scan (BUS) in predicting the need of second-line therapy in ASC.

METHODS

Patients younger than 18 years admitted to a single tertiary referral center with ASC were included. We retrospectively reviewed medical records collecting clinical and BUS data. Colonic wall thickness (CWT), loss of colonic wall stratification (CWS), presence of hyperechoic lymph nodes, and colonic wall flow evaluated at power Doppler were assessed at BUS performed within the third day of hospitalization.

RESULTS

Sixty-nine ASC episodes from 52 different patients were identified. CWT showed significantly higher values in patients who required second-line therapy (5.14 vs 3.69 mm; P < 0.001). Loss of CWS was present in 17 of 36 (47.2%) of steroid-resistant ASC versus only 1 of 33 of those responding to intravenous corticosteroids (P < 0.001, sensitivity = 47%, specificity = 97%). Using a receiver operating characteristic curve, a cut-off of 3.4 mm was individuated for CWT to predict steroid treatment failure, showing a sensitivity of 92% and a specificity of 52%. The multivariable binary logistic regression analysis identified thickened colonic wall (CWT >3.4 mm) and loss of CWS as independent predictors of steroid resistance.

CONCLUSIONS

BUS is a noninvasive, easily accessible, and cost-effective resource that may identify at an early stage first-line therapy failure in pediatric ASC.