Longitudinal Bowel Behavior Assessed by Bowel Ultrasound to Predict Early Response to Anti-TNF Therapy in Patients with Crohn's Disease: A Pilot Study

Background Early changes in bowel behavior during anti-TNF induction therapy in Crohn’s disease (CD) are relatively unknown. We determined (a) onset of changes in bowel behavior in CD patients receiving anti-TNF therapy by ultrasound; and (b) the feasibility of shear wave elastography (SWE) in predicting early response to anti-TNF therapy. Methods Consecutive ileal/ileocolonic CD patients programmed to initiate anti-TNF therapy were enrolled. Bowel ultrasound was performed at baseline, and at weeks 2, 6, and 14. Changes in bowel wall thickness, Doppler signals of the bowel wall (Limberg score), and SWE values were compared using a linear mixed model. Early response to anti-TNF therapy was based on a composite strategy of clinical and colonoscopy assessment at week 14. Results Of the 30 patients enrolled in this study, 20 patients achieved a response to anti-TNF therapy at week 14. The bowel wall thickness and SWE value of the response group showed a significant downward trend compared with the non-response group (P=0.003, P=0.011). Bowel wall thickness, the Limberg score, and SWE values were significantly reduced as early as week 2 compared with baseline (P<0.001, P<0.001, P=0.003) in the response group. Baseline SWE values (21.3±8.7 vs. 15.3±4.7 kPa, P=0.022) and bowel wall thickness (8.5±2.3 vs. 6.9±1.5 mm, P=0.027) in the non-response group were significantly higher than in the response group. Conclusions This pilot study suggested that changes in bowel ultrasound behavior could be assessed as early as week 2 after starting anti-TNF therapy. Bowel ultrasound together with elasticity imaging could predict early response to anti-TNF therapy.

Bowel Ultrasound: a Non-invasive, Easy to Use Method to Predict the Need to Intensify Therapy in Inflammatory Bowel Disease Patients

Background and Aims: Bowel ultrasound (BU) is a non-invasive, inexpensive, widely available tool, valuable for inflammatory bowel disease (IBD) assessment. The aim of the present study was to investigate the clinical utility of BU to predict the need to intensify therapy in IBD patients. Methods: One hundred seventeen IBD patients (89 Crohn’s disease, and 28 ulcerative colitis) diagnosis established at least 6 months before enrolment, undergoing maintenance therapy were prospectively included in the study. Bowel ultrasound investigated the following parameters: the bowel wall thickness (BWT), loss of wall stratification, the presence of the bowel wall Doppler signal, the visible lymph nodes, the mucosal hyperechoic spots, and the irregular external bowel wall. The patients were followed-up for 6 months, registering the need to escalate the treatment regimen. Subgroup analyses were conducted for patients requiring immediate treatment intensification (37 subjects), due to active disease at baseline and patients with subsequent treatment intensification, in the 6 months follow-up period (21 cases) in comparison to patients that required no therapeutic optimization (59). Results: During the follow-up, 49.6% of patients needed treatment escalation. All the investigated BU variables were significantly associated with the main outcome. In the multivariate analysis, the mean BWT (p<0.0001), and the presence of the bowel wall Doppler signal (p=0.007) were independent predictors of the main outcome. For the subgroup analyses: mean BWT (p=0.0001) and the presence of the bowel wall Doppler signal (p=0.01) were independent predictors for immediate treatment intensification (active disease at baseline) and mean BWT (p=0.0003) and the lack of bowel wall stratification (p=0.05) were independent predictors for the need of subsequent therapeutic optimization. Logistic regression prediction models and prediction scores (BU score) had the best AUROC values (>0.91) when compared to traditional biomarkers of active inflammation, such as C reactive protein or fecal calprotectin. Conclusion: Bowel ultrasound could be used as a non-invasive, easy to use diagnostic tool to predict the need to intensify therapy in patients with IBD.

Bowel Ultrasound in Inflammatory Bowel Disease: How Far in the Grayscale?

Bowel ultrasound (BUS) is a non-invasive and accurate technique for assessing activity, extension of disease, and complications in inflammatory bowel diseases. The main advantages of BUS are its safety, reproducibility, and low costs. Ancillary technologies of BUS (i.e., color Doppler and wave elastography) could broaden the diagnostic power of BUS, allowing one to distinguish between inflammation and fibrosis. Considering the costs and invasiveness of colonoscopy and magnetic resonance, BUS appears as a fast, safe, and accurate technique. The objective measures of disease allow one to make clinical decisions, such as optimization, switch, or swap of therapy. Previous studies reported a sensitivity and a specificity of more than 90% compared to endoscopy and magnetic resonance. Lastly, transperineal ultrasound (TPUS) is a promising approach for the evaluation of perianal disease in Crohn’s disease (CD) and disease activity in patients with ulcerative proctitis or pouchitis. Bowel ultrasound is being incorporated in the algorithm of managing inflammatory bowel diseases. Transmural healing evaluated through ultrasonography is emerging as a complementary target for disease treatment. In this review, we aimed to summarize and discuss the current evidence on BUS in the management of inflammatory bowel diseases and to address the challenges of a full validation of this technique.

Clinical utility of small bowel ultrasound assessment of Crohn’s disease in adults: a systematic scoping review

BackgroundUltrasound (US) is an alternative to magnetic resonance enterography, and has the potential to significantly reduce waiting times, expedite clinical decision-making and improve patient experience. Point of care US is an advantage of the US imaging modality, where same day scanning, interpretation and treatment decisions can be made.AimTo systematically scope the literature on point of care US use in small bowel Crohn’s disease, generating a comprehensive list of factors relating to the current understanding of clinical utility of this imaging modality.MethodsSearches included MEDLINE, EMBASE, Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, clinicaltrial.gov,‘TRIP’ and Epistemonikos. Reference lists of included studies were hand searched. Search terms were searched for as both keywords and subject headings (MeSH) as appropriate. Searches were performed with the ‘suggested search terms’ and ‘explode’ selection, and restricted to ‘human’, ‘adult’ and ‘English language’ publications. No date limits were applied to be as inclusive as possible. Two investigators conducted abstract and full-text review. No formal quality appraisal process was undertaken; however, quality of sources was considered when reporting findings. A narrative synthesis was conducted.ResultsThe review included 42 sources from the UK, Europe, Japan, Canada and the USA. Small bowel ultrasound (SBUS) has been shown to be as accurate in detecting the presence of small bowel Crohn’s disease, is quicker, safer and more acceptable to patients, compared with magnetic resonance enterography. SBUS is used widely in central Europe and Canada but has not been embraced in the UK. Further research considering economic evaluation, clinical decision-making and exploration of perceived barriers to future implementation of SBUSs is required.

P400 Bowel ultrasonography, a non invasive easy-to-use method to predict the need to step-up therapy in inflammatory bowel disease patients

Background Inflammatory bowel diseases (IBD) are chronic conditions that require multiple endoscopic and imaging assessments. Recent guidelines recommend bowel ultrasonography (BUS) as a complimentary imaging technique to assess transmural and extraintestinal lesions. The aim of the present study was to evaluate the accuracy of BUS in predicting the need to step-up therapy in IBD patients. Methods 117 IBD patients were included in the study (28 diagnosed with ulcerative colitis, 89 with Crohn’s disease). Following bowel ultrasound features bowel ultrasound features have been investigated: bowel wall thickness, loss of wall stratification, presence of bowel wall Doppler signal, the presence of hyperechoic spots inside the bowel wall, the irregularity of the external layer of the wall, the presence of creeping fat (mesenteric hypertrophy), the presence of visible lymph nodes. Patients were followed up for the next 6 months and data regarding their therapy was noted. Results During follow-up, therapeutic step-up, or biological treatment intensification (study outcome) were considered in 49.5% of cases in our study group. In a univariate analysis all the studied bowel ultrasound features but not the disease phenotype were significantly associated with the outcome. In the multivariate analysis only mean bowel wall thickness (&lt;0.0001) and the presence of bowel wall Doppler signal (0.007) were independent predictors. Using the logistic regression prediction model, a score to evaluate the need of IBD treatment intensification could be calculated - Bowel Ultrasound Score (BU Score). The AUROC of the new BU score as a predictor for treatment intensification at 6 months in patients with IBD is 0.92, with a sensitivity of 84% and a specificity of 89%, indicating a good clinical utility. For the same outcome, AUROC for CRP was 0.81 whereas for fecal calprotectin was 0.85. Conclusion As the “treat to target concept” is the currently accepted novel treatment paradigm, incorporating BUS in IBD patients monitoring (BU score) provides an easy-to-use and readily available tool to stratify patients in need for therapeutic intensification.

P152 Bowel ultrasound as an early monitoring tool to assess disease activity in Crohn’s disease patients after induction therapy with infliximab

Background Bowel wall thickness (BWT) is an accurate sonographic parameter to assess disease activity in Crohn’s disease (CD). International Bowel Ultrasound Segmental Activity Score (IBUS-SAS) was developed to allow a reproducible assessment of intestinal inflammation in CD using bowel ultrasound (IUS). Aim to assess BWT and IBUS-SAS variation after induction therapy with infliximab (IFX) and their correlation with clinical and laboratory parameters. Methods Prospective multicentre study including patients with active CD starting IFX. Harvey-Bradshaw index (HBI), C-reactive protein (CRP), faecal calprotectin (FC) and IUS were performed at week 0 (W0) and 14 (W14). IUS response and remission were defined as a reduction in BWT ≥25% and its normalization(≤3mm) in the most affected segment, respectively. IBUS-SAS was calculated using BWT, Doppler signal, bowel wall stratification (BWS) and inflammatory fat. Results We included 37 patients (62% males; median age 30 years, range 16–73). According to Montreal classification, most patients were A2 (70%), had ileocolonic disease (L3 57%) and an inflammatory phenotype (B1 60%); 41% had perianal disease. Most were anti-TNF therapy naive(84%), and combination therapy was used in 62%. Terminal ileum was the most affected segment identified by IUS (60%). Table 1 shows clinical, laboratory and sonographic parameters [median (IQR)]. At W14, 81% were in clinical remission, 43% in laboratorial remission (normal CRP and FC), 24% had IUS response and 11% had IUS remission. There was a significant reduction in HBI, CRP, FC and sonographic parameters (except for BWS) between W0 and W14. We found a fair to good correlation between BWT and HBI(r=0.363, p=0.03), CRP(r=0.391, p=0.02) and FC(r=0.373, p=0.03) at W14. IBUS-SAS had also a fair to good correlation with CRP(r=0.340, p=0.04) and FC(r=0.527, p=0.001) at W14. The area under the curve of IBUS-SAS for predicting clinical and laboratorial remission was 0.60; best-cut off 64.65 (sens. 57%; specif. 63%). Conclusion There was a significant reduction in sonographic parameters after 14 weeks of IFX and one quarter of our patients had an IUS response, suggesting that reduction in BWT could be an early marker of response to therapy. We found a good correlation between IUS and clinical and laboratory parameters at W14. IUS evaluation after induction therapy can be a helpful tool to monitor disease activity and guide CD patient management in our daily practice.