Milan ultrasound criteria are accurate in assessing disease activity in ulcerative colitis: external validation

Artificial intelligence and endo-histo-omics: new dimensions of precision endoscopy and histology in inflammatory bowel disease

Integrating artificial intelligence into inflammatory bowel disease (IBD) has the potential to revolutionise clinical practice and research. Artificial intelligence harnesses advanced algorithms to deliver accurate assessments of IBD endoscopy and histology, offering precise evaluations of disease activity, standardised scoring, and outcome prediction. Furthermore, artificial intelligence offers the potential for a holistic endo-histo-omics approach by interlacing and harmonising endoscopy, histology, and omics data towards precision medicine. The emerging applications of artificial intelligence could pave the way for personalised medicine in IBD, offering patient stratification for the most beneficial therapy with minimal risk. Although artificial intelligence holds promise, challenges remain, including data quality, standardisation, reproducibility, scarcity of randomised controlled trials, clinical implementation, ethical concerns, legal liability, and regulatory issues. The development of standardised guidelines and interdisciplinary collaboration, including policy makers and regulatory agencies, is crucial for addressing these challenges and advancing artificial intelligence in IBD clinical practice and trials.

Drug Optimization in Patients with Mild-to-Moderate Ulcerative Colitis: A Global Survey

Background/Objectives: The treatment of patients with mild-to-moderate ulcerative colitis (UC) is challenging. Although there are commonly used guidelines, therapy optimization is not standardized. We conducted a survey to investigate the management and treatment of patients with mild-to-moderate UC. Methods: Physicians with experience in treating inflammatory bowel diseases (IBD) were invited to participate in an anonymous, multiple-choice survey between June and July 2023. The survey addressed various issues of patient care such as patient monitoring, treatment optimization, follow-up, treatment decision making, and therapy de-escalation. Results: The survey included 222 physicians (59.9% men; mean age = 50.4 years) from 66 countries worldwide. Gastroenterologists were the most represented specialists (89.6%), followed by surgeons (3.2%), and internal medicine doctors (2.7%). Two-thirds of the participants (66.7%) had >10 years of experience in the field of IBD. The combination of oral (≥4 g/day) and rectal 5-aminosalicylic acid (5-ASA) was the preferred choice when optimizing therapy. Budesonide MMX (41.8%) and systemic steroids (39.9%) were preferred in patients who failed 5-ASA. Treatment decisions were predominantly based on endoscopic (99.0%) or clinical (59.8%) activity. A significant percentage of clinicians did not optimize therapy in the case of increased fecal calprotectin alone (45.1%) or radiological/ultrasound activity (39.8%) alone. Conclusions: The guidelines for the management of mild-to-moderate UC are well accepted in clinical practice. Endoscopic remission remains the main therapeutic target, followed by clinical remission. Fecal calprotectin and intestinal ultrasound still elicit complaints from physicians.

Intestinal ultrasound scan predicts corticosteroid failure and colectomy risk in patients with ulcerative colitis

OBJECTIVE

Intestinal ultrasound (IUS) is an emerging modality for assessing disease activity, extent, and treatment response in ulcerative colitis. This study aimed to evaluate the potential of IUS in predicting severe flares, the need for rescue therapy (corticosteroid failure), and colectomy in patients with ulcerative colitis.

METHODS

We conducted a retrospective review of medical records, collecting clinical and IUS data. The Milan Ultrasound Criteria (MUC) score was used to assess ulcerative colitis severity. Group comparisons were performed to identify differences in MUC scores between mild-to-moderate and severe ulcerative colitis, between steroid responders and nonresponders, and between patients who underwent colectomy and those who did not. Receiver operating characteristic (ROC) analysis was used to predict outcomes in patients with ulcerative colitis.

RESULTS

This analysis included 102 patients with ulcerative colitis categorized as mild/moderate (60) or severe (42). MUC scores were significantly higher in the severe ulcerative colitis group compared with the mild/moderate group (P < 0.001). Analysis (using ROC) identified a cutoff MUC score of >8.54 to indicate severe ulcerative colitis with good sensitivity (64.29%) and excellent specificity (93.33%). Similarly, a cutoff of MUC > 10.54 showed promise in predicting corticosteroid failure, with acceptable sensitivity (50%) and high specificity (90.91%). Finally, a cutoff MUC score >12.5 demonstrated potential for predicting colectomy, exhibiting moderate sensitivity (55.56%) but excellent specificity (96.97%).

CONCLUSION

IUS may be useful for differentiating severe ulcerative colitis from mild-to-moderate disease, identifying early stage failure of corticosteroid therapy, and predicting the potential need for colectomy.

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.

A combination of bowel wall thickness and submucosa index is useful for estimating endoscopic improvement in ulcerative colitis: external validation of the Kyorin Ultrasound Criterion

BACKGROUND

Endoscopic improvement (EI; a Mayo endoscopic subscore of 0 or 1) is considered a therapeutic target in ulcerative colitis (UC) treatment. The potential to estimate EI non-invasively is an advantage of intestinal ultrasound (IUS). In a previous study, we developed a new sonographic parameter, the submucosa index (SMI), calculated as the ratio of the submucosal thickness to bowel wall thickness (BWT), and reported that combining BWT and SMI results in a practical and promising criterion for estimating EI without color Doppler assessment. This study aimed to validate the EI estimation ability of our B mode-based criterion, the 'Kyorin Ultrasound Criterion for UC' (KUC-UC; BWT < 3.8 mm and SMI < 50%), using an external cohort.

METHODS

Patients with UC who underwent IUS and colonoscopy within 15 days without a treatment change between examinations were included. IUS findings, including BWT, SMI, and modified Limberg score for vascularity of the colon, were assessed.

RESULTS

Forty-four test pairs of IUS and colonoscopy examinations in a total of 122 colonic segments were analyzed. The KUC-UC showed positive predictive value (PPV) of 94.6% and negative predictive value (NPV) of 80.0% for EI. In comparison, PPV and NPV were 85.4% and 79.0%, respectively, for the common criterion BWT of < 3 mm, and 83.0% and 82.7% for the validated Milan Ultrasound Criteria (a score of ≤ 6.2).

CONCLUSIONS

External validation showed that the KUC-UC using only B mode findings without complicated calculations is a feasible and accurate sonographic criterion for estimating the EI of UC.

Superior predictive value of transmural over endoscopic severity for colectomy risk in ulcerative colitis: a multicentre prospective cohort study

BACKGROUND AND AIMS

Endoscopic activity is associated with an increased risk of surgery in patients with ulcerative colitis [UC]. Transmural activity, as defined by Milan Ultrasound Criteria [MUC] > 6.2, reliably detects endoscopic activity in patients with UC. The present study aimed to assess in UC patients whether transmural severity is a better predictor of colectomy as compared to endoscopy.

METHODS

Consecutive adult UC patients were recruited in two IBD Referral Centres and underwent colonoscopy and intestinal ultrasound in a blinded fashion. The need for colectomy was assessed at follow-up. Univariable and multivariable logistic and Cox regression analyses were performed. Receiver operating characteristic [ROC] analysis was used to compare MUC baseline values and Mayo Endoscopic Scores [MES] in predicting colectomy risk.

RESULTS

Overall, 141 patients were enrolled, and 13 underwent colectomy in the follow-up period. Both MES (hazard ratio [HR]: 3.15, 95% confidence interval [CI]: 1.18-8.37, p = 0.02) and MUC [HR: 1.48, 95% CI: 1.19-1.76, p < 0.001] were associated with colectomy risk, but only MUC was independently associated with this event on multivariable analysis [HR: 1.46, 95% CI: 1.06-2.02, p = 0.02]. MUC was the only independent variable associated with colectomy risk in patients with clinically active disease (odds ratio [OR]: 1.53 [1.03-2.27], p = 0.03). MUC demonstrated higher accuracy than MES (area under ROC curve [AUROC] 0.83, 95% CI: 0.75-0.92 vs 0.71, 95% CI: 0.62-0.80) and better performance for predicting colectomy [p = 0.02]. The optimal MUC score cut-off value for predicting colectomy, as assessed by the Youden index, was 7.7.

CONCLUSIONS

A superior predictive value was found for transmural vs endoscopic severity for colectomy risk in UC patients.

Composite Assessment Using Intestinal Ultrasound and Calprotectin Is Accurate in Predicting Histological Activity in Ulcerative Colitis: A Cohort Study

BACKGROUND

Beyond endoscopic remission, histological remission in ulcerative colitis (UC) is predictive of clinical outcomes. Intestinal ultrasound (IUS) may offer a noninvasive surrogate marker for histological activity; however, there are limited data correlating validated ultrasound and histological indices.

AIM

Our aim was to determine the correlation of IUS activity in UC with a validated histological activity index.

METHODS

Twenty-nine prospective, paired, same-day IUS/endoscopy/histology/fecal calprotectin (FC) cases were included. Intestinal ultrasound activity was determined using the Milan Ultrasound Criteria, histological activity using the Nancy Histological Index, endoscopic activity using Mayo endoscopic subscore and Ulcerative Colitis Endoscopic Index of Severity, and clinical activity using the Simple Clinical Colitis Activity Score.

RESULTS

Histological activity demonstrated a significant linear association with overall IUS activity (coefficient 0.14; 95% CI, 0.03-0.25; P = .011). Intestinal ultrasound activity was also significantly associated with endoscopic activity (0.32; 95% CI, 0.14-0.49; P < 0.001), total Mayo score (0.31; 95% CI, 0.02-0.60; P = .036) but not FC (0.10; 95% CI, -0.01 to 0.21; P = .064) or clinical disease activity (0.04; 95% CI, -0.21 to 0.28; P = .768). A composite of IUS and FC showed the greatest association (1.31; 95% CI, 0.43-2.18; P = .003) and accurately predicted histological activity in 88% of cases (P = .007), with sensitivity of 88%, specificity 80%, positive predictive value 95%, and negative predictive value 57%.

CONCLUSIONS

Intestinal ultrasound is an accurate noninvasive marker of histological disease activity in UC, the accuracy of which is further enhanced when used in composite with FC. This can reduce the need for colonoscopy in routine care by supporting accurate point-of-care decision-making in patients with UC.

Leaving behind the Mucosa: Advances and Future Directions of Intestinal Ultrasound in Ulcerative Colitis

Inflammatory Bowel Diseases (IBD), mainly Ulcerative Colitis (UC) and Crohn's Disease (CD), are disorders characterized by chronic inflammation with severe morbidity and long-term disabling quality of life outcomes. UC mainly affects the mucosal and sub-mucosal layers of the colon, without embracing the peri-intestinal structures. Considering the predominant mucosal location of UC inflammation, the implementation of transmural evaluation by cross-sectional imaging techniques, mainly Intestinal Ultrasound (IUS), has been left behind for ages, especially if compared to CD. Nevertheless, studies analyzing intestinal ultrasound parameters accuracy in disease activity detection reported a good-to-optimal correlation of IUS markers with colonic inflammation, suggesting comparable feasibility of IUS monitoring in UC as in CD. The easy-to-use, costless and point-of-care available status of IUS is therefore crucial in order to improve the diagnostic process and, according to the recent literature, to monitor the response to treatment leading to speeding up decision making and therapy adjustments. Recent studies have demonstrated the correlation between transmural healing in UC with favorable outcomes even in the long term. An evidence gap still exists in the assessment of the rectum, with trans-perineal ultrasound (TPUS) a potential answer to reach a more precise evaluation of rectal inflammation. Eventually, IUS is also increasingly showing promises in emergent or post-surgical UC settings, considering various efforts put in line to demonstrate its feasibility in predicting response to salvage therapy for surgery avoidance and in studying inflammation relapse after procto-colectomy with ileo-pouch-anal anastomosis (IPAA) creation.

Milan Ultrasound Criteria Predict Relapse of Ulcerative Colitis in Remission

Introduction

Bowel ultrasound is a noninvasive alternative to endoscopy for assessing the disease activity of ulcerative colitis; however, it is unclear whether bowel ultrasound can predict subsequent relapse from remission.

Materials and Methods

A retrospective cohort study enrolled patients with ulcerative colitis who underwent bowel ultrasound between July 2018 and July 2021 during clinical remission (patient-reported outcome-2 ≤1 and no rectal bleeding) for at least 3 months and were followed up for 1 year. Ultrasonographic findings (bowel wall thickness, bowel wall flow, bowel wall stratification, and enlarged lymph nodes), Milan ultrasound criteria, Mayo endoscopic subscore, C-reactive protein, and fecal calprotectin levels and their association with subsequent clinical relapse were assessed. Relapse was defined as rectal bleeding score ≥1, stool frequency score ≥2, or treatment intensification for symptoms.

Results

31% of the patients (18/58) relapsed within 1 year. No single ultrasonographic finding predicted relapse, whereas Milan ultrasound criteria >6.2 (p = 0.019), Mayo endoscopic subscore ≥1 (p = 0.013), and fecal calprotectin ≥250 μg/g (p = 0.040) were associated with a shorter time to relapse in the log-rank test. Milan ultrasound criteria >6.2 (hazard ratio 3.22; 95% confidence interval 1.14-9.08, p = 0.027) and Mayo endoscopic subscore ≥1 (hazard ratio 8.70; 95% confidence interval 1.11-68.1, p = 0.039) showed a higher risk of relapse according to a Cox proportional hazards model.

Conclusion

Bowel ultrasound can predict subsequent clinical relapse from remission in patients with ulcerative colitis using the Milan ultrasound criteria.

Early Intestinal Ultrasound Predicts Long-Term Endoscopic Response to Biologics in Ulcerative Colitis

BACKGROUND AND AIMS

The Milan ultrasound criteria [MUC] is a validated score to assess endoscopic activity in ulcerative colitis [UC]. MUC > 6.2 detects Mayo endoscopic score [MES] > 1. In this study we evaluated the predictive value of MUC for biologic treatment response, using colonoscopy [CS] as a reference standard.

METHODS

Consecutive UC patients starting biologic therapy were included, and underwent CS, IUS, clinical assessment and faecal calprotectin [FC] measurement at baseline and within 1 year. In addition, IUS, clinical and FC assessments were performed at week 12. The primary objective was to evaluate whether ultrasound improvement [MUC ≤ 6.2] at week 12 predicted endoscopic improvement at reassessment [MES ≤ 1]. Endoscopic remission was defined as MES = 0.

RESULTS

Forty-nine patients were included [59% under infliximab, 29% under vedolizumab, 8% under adalimumab, 4% under ustekinumab]. MUC ≤ 6.2 at week 12 was the only independent predictor for MES ≤ 1 and MES = 0 at reassessment (odds ratio [OR] 5.80, p = 0.010; OR 10.41, p = 0.041; respectively). MUC ≤ 6.2 at week 12 showed a negative predictive value of 96% for detecting MES = 0. A ≥2 reduction of the MUC predicted MES = 0 (area under the curve [AUC] 0.816). MUC ≤ 4.3 was the most accurate cut-off value for MES = 0 [AUC 0.876]. Guyatt's responsiveness ratio for the MUC was 1.73 [>0.8].

CONCLUSION

MUC ≤ 6.2 at week 12 predicts long-term endoscopic response. MUC is accurate in monitoring treatment response and may be used in both clinical trials and routine practice.

Predicting Treatment Response in Inflammatory Bowel Diseases: Cross-Sectional Imaging Markers

Therapeutic options for inflammatory bowel diseases (IBD) have largely expanded in the last decades, both in Crohn's disease and ulcerative colitis, including multiple biological drugs targeting different inflammation pathways. However, choosing the best treatment and timing for each patient is still an undeniable challenge for IBD physicians due to the marked heterogeneity among patients and disease behavior. Therefore, early prediction of the response to biological drugs becomes of utmost importance, allowing prompt optimization of therapeutic strategies and thus paving the way towards precision medicine. In such a context, researchers have recently focused on cross-sectional imaging techniques (intestinal ultrasound, computed tomography, and magnetic resonance enterography) in order to identify predictive markers of response or non-response to biologic therapies. In this review, we aim to summarize data about imaging factors that may early predict disease behavior during biological treatment, potentially helping to define more precise and patient-tailored strategies.

Intestinal ultrasound as a non-invasive tool to monitor inflammatory bowel disease activity and guide clinical decision making

Intestinal ultrasound (IUS) is a non-invasive, real-time, cross-sectional imaging tool that can be used at the point-of-care to assess disease activity in patients with Crohn’s disease or ulcerative colitis. IUS promotes quick and impactful treatment decisions that can modify disease progression and enhance patient compliance. This review will summarize the technical aspects of IUS, the evidence to support the use of IUS in disease activity monitoring, the comparison of IUS to current standard of care monitoring modalities such as colonoscopy and calprotectin, and the optimal positioning of IUS in a tight-control monitoring strategy.

Intestinal Ultrasound in Inflammatory Bowel Disease: A Novel and Increasingly Important Tool

New and efficacious medical therapies have become available that have greatly enhanced clinicians' ability to manage inflammatory bowel diseases (IBDs). IBD activity should be assessed regularly in scheduled examinations as the part of a treat-to-target strategy for IBD care. The gold-standard approach to investigating IBD is colonoscopy, but this is an invasive procedure. Intestinal ultrasound (IUS) has played a crucial role in recent years regarding the assessment of IBD activity because it is noninvasive, safe, reproducible, and inexpensive. IUS findings could inform changes in therapeutic interventions for IBDs; this would necessitate fewer endoscopies and enable faster decision-making processes. Furthermore, patients are accepting and tolerant of IUS examinations. This review outlines the current evidence and gives indication regarding the use of IUS in the management of IBDs.

First aid with color atlas for the use of intestinal ultrasound for inflammatory bowel disease in daily clinical practice

Intestinal ultrasound (IUS) is a promising modality for the management of inflammatory bowel disease (IBD) and has the potential to particularly contribute in monitoring disease activity, an advantage crucial for optimizing the therapeutic strategy. While many IBD physicians appreciate and are interested in the use of IUS for IBD, currently only a limited number of facilities can employ this examination in daily clinical practice. A lack of guidance is one of the major barriers to introducing this procedure. Standardized protocols and assessment criteria are needed such that IUS for IBD can be considered a feasible, reliable examination in clinical practice, and multicenter clinical studies can be conducted for further clinical evidence of the application of IUS in IBD for best patient care. In this article, we provide an overview of how to start IUS for IBD and introduce basic procedures. Furthermore, IUS images from our practice are provided as a color atlas for understanding sonographic findings and scoring systems. We anticipate this "first aid" article will be helpful to promote IUS for IBD in daily practice.

The Arrival of Intestinal Ultrasound for Inflammatory Bowel Disease Care in the United States

Intestinal ultrasound (IUS) is a noninvasive and highly reliable point-of-care tool to evaluate inflammation of the bowel. It offers comparable accuracy to endoscopy and magnetic resonance enterography. Although IUS has been incorporated into the management of inflammatory bowel disease (IBD) in other parts of the world, it has only recently arrived in the United States. However, barriers to integration of IUS into IBD care in the United States have included a lack of adoption by leading centers, lack of educational opportunities, and an unclear path for remuneration. This article provides information about the use of IUS in IBD, reviews the data comparing existing modalities of assessment of IBD with IUS, and summarizes strategies to overcome existing barriers to IUS implementation, including the newly available US-based training pathway and appropriate billing practice.

The use of ultrasound in colonic and perianal diseases

PURPOSE OF REVIEW

To revise recent literature findings regarding the use of ultrasound in colonic and perianal diseases by focusing particularly on its feasibility in inflammatory bowel diseases (IBD), colorectal neoplastic lesions, and perineal diseases, with further highlight on interventional capabilities.

RECENT FINDINGS

Treat-to-target approach in IBD raised an interest in intestinal ultrasound (IUS) for monitoring bowel activity considering its noninvasive nature, low costs, and well tolerability. New IUS indices have been developed with ever better methodologies and are at various stage of validation. A standardized over-the-wire technique for colonic US using a flexible overtube enables endoscopic ultrasound (EUS)-guided tissue sampling beyond the rectum, and forward-viewing radial-array echoendoscopes can assist identification of early neoplastic lesions in proximal colon. Intraoperative ultrasound and contrast-enhanced ultrasound carry an additional diagnostic value compared to conventional preoperative imaging modalities in detecting colorectal cancer liver metastases (CRLM).

SUMMARY

The feasibility of IUS in monitoring IBD activity is supported by growing evidence, but uniform IUS indices are still lacking. Recent advancements in EUS are expanding capabilities for determining depth of invasion of colorectal neoplasms, tissue sampling, and EUS-guided interventions to the entire colon. Ultrasonography can be a valuable tool in CRLM diagnostics as well.

Recent advances in clinical practice: advances in cross-sectional imaging in inflammatory bowel disease

Endoscopy remains the reference standard for the diagnosis and assessment of patients with inflammatory bowel disease (IBD), but it has several important limitations. Cross-sectional imaging techniques such as magnetic resonance enterography (MRE) and intestinal ultrasound (IUS) are better tolerated and safer. Moreover, they can examine the entire bowel, even in patients with stenoses and/or severe inflammation. A variety of cross-sectional imaging activity scores strongly correlate with endoscopic measures of mucosal inflammation in the colon and terminal ileum. Unlike endoscopy, cross-sectional techniques allow complete visualisation of the small-bowel and assess for extraintestinal disease, which occurs in nearly half of patients with IBD. Extramural findings may predict outcomes better than endoscopic mucosal assessment, so cross-sectional techniques might help identify more relevant therapeutic targets. Coupled with their high sensitivity, these advantages have made MRE and IUS the primary non-invasive options for diagnosing and monitoring Crohn's disease; they are appropriate first-line investigations, and have become viable alternatives to colonoscopy. This review discusses cross-sectional imaging in IBD in current clinical practice as well as research lines that will define the future role of these techniques.

Intestinal Ultrasound to Assess Ulcerative Colitis Disease Activity in Children: External Validation and Comparison of 2 Intestinal Ultrasound Activity Indices

BACKGROUND

There is currently no consensus on the definition of an abnormal intestinal ultrasound (IUS) for children with ulcerative colitis (UC). This cross-sectional study aimed to externally validate and compare 2 existing IUS indices in children with UC.

METHODS

Children undergoing colonoscopy for UC assessment underwent IUS the day before colonoscopy, assessed with the Mayo endoscopic subscore. The UC-IUS index and the Civitelli index were compared with the Mayo endoscopic score in the ascending, transverse, and descending colon. The area under the receiver-operating characteristic curve for detecting a Mayo endoscopic score ≥2 of both scores was compared and sensitivity and specificity were calculated.

RESULTS

A total of 35 UC patients were included (median age 15 years, 39% female). The area under the receiver-operating characteristic curve was higher for the UC-IUS index in the ascending colon (0.82 [95% confidence interval (CI), 0.67-0.97] vs 0.76 [95% CI, 0.59-0.93]; P = .046) and transverse colon (0.88 [95% CI, 0.76-1.00] vs 0.77 [95% CI, 0.60-0.93]; P = .01). In the descending colon, there was no difference (0.84 [95% CI, 0.70-0.99] vs 0.84 [95% CI, 0.70-0.98]). The optimal cutoff for the UC-IUS was <1 point to rule out a Mayo endoscopic score ≥2 (sensitivity: 88%, 100%, and 90% in the ascending, transverse, and descending colon, respectively) and a Mayo endoscopic score ≥2 could be detected using a cutoff of >1 (specificity: 84%, 83%, and 87%, respectively). For the Civitelli index, in our cohort, the optimal cutoff was <1 to rule out a Mayo endoscopic score ≥2 (sensitivity 75%, 65%, and 80%, respectively) and a cutoff >1 to detect a Mayo endoscopic score ≥2 (specificity 89%, 89%, and 93%, respectively).

CONCLUSIONS

In this cohort, the UC-IUS index performed better than the Civitelli index. The UC-IUS index had both a high sensitivity and specificity in this cohort, when using 1 point as cutoff for a Mayo endoscopic score ≥2.

Intestinal Elastography in the Diagnostics of Ulcerative Colitis: A Narrative Review

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that mainly affects developed countries, but the number of cases in developing countries is increasing. We conducted a narrative review on the potential application of ultrasound elastography in the diagnosis and monitoring of UC, as this newly emerging method has promising results in other gut diseases. This review fulfilled the PRISMA Statement criteria with a time cut-off of June 2022. At the end of the review, of the 1334 identified studies, only five fulfilled all the inclusion criteria. Due to the small number of studies in this field, a reliable assessment of the usefulness of ultrasound elastography is difficult. We can only conclude that the transabdominal elastography examination did not significantly differ from the standard gastrointestinal ultrasonography examination and that measurements of the frontal intestinal wall should be made in the longitudinal section. The reports suggest that it is impossible to estimate the clinical scales used in disease assessment solely on the basis of elastographic measurements. Due to the different inclusion criteria, measurement methodologies, and elastographic techniques used in the analysed studies, a reliable comparative evaluation was impossible. Further work is required to assess the validity of expanding gastrointestinal ultrasonography with elastography in the diagnosis and monitoring of UC.

Ultrasound Elastography in Inflammatory Bowel Diseases: A Systematic Review of Accuracy Compared with Histopathological Assessment

BACKGROUND AND AIMS

Ultrasound elastography [USE] is an innovative, non-invasive, promptly available, ancillary technique that has been proposed in the evaluation of intestinal fibrosis as a monitorable biomarker, in terms of stiffness. The non-invasive estimate of fibrosis by USE appears appealing for dedicated physicians, in order to optimise the treatments for inflammatory bowel disease [IBD] patients [surgical vs non-surgical]. We aimed to systematically review literature evidence on ultrasound elastography in IBD patients.

METHODS

For this qualitative systematic review, we searched PubMed, EMBASE, and Scopus to identify all studies, published until October 2021, investigating the application of USE in IBD patients compared with histopathological assessment.

RESULTS

Overall, 12 papers published between 2011 and 2019 were included. A total of 275 IBD patients were included: 272 Crohn's disease [CD] [98.9%] and three ulcerative colitis [UC] [1.1%]. Seven [58.3%] and four [41.6%] studies investigated strain elastography [SE] and shear wave elastography [SWE], respectively; in one study [0.1%] both techniques were addressed. The histological evaluation was largely conducted on surgical specimens and in two studies endoscopic biopsies were also included. The histological assessment was semi-quantitative in all the included studies, except for two where the fibrosis was evaluated only qualitatively. In 10/12 publications USE could accurately distinguish inflammation from fibrosis in the examined bowel tracts.

CONCLUSIONS

From the preliminary available data, an overall moderate-to-good accuracy of USE in detecting histological fibrosis [10/12 studies] was found. Point-shear wave elastography has been shown to perform superiorly. Further studies are needed to confirm these evidences.

[Position paper on reporting of intestinal ultrasound findings in patients with inflammatory bowel disease]

BACKGROUND

Intestinal ultrasound is increasingly used for primary diagnosis, detection of complications and monitoring of patients with Crohn's disease and ulcerative colitis. Standardization of reporting is relevant to ensure quality of the methodology and to improve communication between different specialties. The current manuscript describes the features required for optimized reporting of intestinal ultrasound findings in inflammatory bowel disease (IBD).

METHODS

An expert consensus panel of gastroenterologists, radiologists, pathologists, paediatric gastroenterologists and surgeons conducted a systematic literature search. In a Delphi- process members of the Kompetenznetz Darmerkrankungen in collaboration with members of the German Society for Radiology (DRG) voted on relevant criteria for reporting of findings in intestinal ultrasound. Based on the voting results statements were agreed by expert consensus.

RESULTS

Clinically relevant aspects of intestinal ultrasound (IUS) findings have been defined to optimize reporting and to standardize terminology. Minimal requirements for standardized reporting are suggested. The statements focus on description of disease activity as well as on complications of IBD. Attributes of intestinal inflammation are described and illustrated by exemplary images.

CONCLUSION

The current manuscript provides practical recommendations on how to standardize documentation and reporting from intestinal ultrasound findings in patients with IBD.

The Impact of Intestinal Ultrasound on the Management of Inflammatory Bowel Disease: From Established Facts Toward New Horizons

Intestinal ultrasound (IUS) plays a crucial role as a non-invasive and accurate tool to diagnose and assess inflammatory bowel disease (IBD). The rationale for using IUS in Crohn’s disease (CD), a transmural disease, is widely acknowledged. While the use of IUS in ulcerative colitis (UC), a mucosal disease, is often underestimated, but, recently, it is increasingly expanding. In the context of a treat-to-target approach, the role of IUS is shifting toward a monitoring tool for predicting response to therapy. Hence, adjusting therapeutic strategies based on IUS response could reduce the burden related to endoscopy and speed the decision process with the ultimate goal to alter the natural course of IBD. Assessment of bowel wall thickness (BWT) is the most reliable IUS measure. However, the development of validated and reproducible sonographic scores to measure disease activity and the identification of parameters of therapeutic response remain relevant issues to implement the daily adoption of IUS in clinical practice. Accordingly, this review focuses on the current literature investigating the impact of IUS on CD with emphasis on the concept of transmural healing (TH) and the main related advantages. We further explore new insights on the role of IUS in UC and its clinical implications.

Point-of-Care Testing and Home Testing: Pragmatic Considerations for Widespread Incorporation of Stool Tests, Serum Tests, and Intestinal Ultrasound

Breaking through the biologic therapy efficacy plateau for inflammatory bowel disease requires the strategic development of personalized biomarkers in the tight control model. After risk stratification early in the disease course, targeted serial monitoring consistently to assess clinical outcomes in response to therapy allows for quick therapeutic adjustments before bowel damage can occur. Point-of-care intestinal ultrasound performed by the treating gastroenterologist is an accurate cross- sectional biomarker that monitors intestinal inflammation in real-time, enhances patient care, and increases shared understanding to help achieve common treatment goals. Combining intestinal ultrasound during a clinic visit with existing serum and stool biomarkers in a home testing setup with electronic health monitoring allows for an optimized, patient-centered personalized treatment algorithm that may improve treatment outcomes. Here, we review the current state, pragmatic considerations, and future implications of point-of-care testing and home testing for noninvasive inflammatory bowel disease monitoring in the tight control model.

Predictive value of Milan ultrasound criteria in ulcerative colitis: A prospective observational cohort study

Background

Endoscopic healing is an established treatment target for ulcerative colitis (UC). We have recently validated the Milan ultrasound criteria (MUC) to assess endoscopic activity in UC; a MUC score > 6.2 is a valid cut‐off to discriminate endoscopic activity (Mayo endoscopic subscore > 1).

Objective

The aim of this study was to assess the predictive value of MUC on disease course in a prospective cohort of UC patients.

Methods

UC patients regardless of disease activity and current therapy, underwent colonoscopy and bowel ultrasound (US) at baseline in a blinded fashion. Correlations between baseline MUC and Mayo endoscopic subscore were assessed using Spearman's rank correlation. UC‐related negative course (defined as the need for corticosteroids, or treatment escalation, or hospitalization, or need for colectomy: a composite outcome) over a median 20 months follow‐up, was investigated using the Kaplan‐Meier method and Cox regression analysis.

Results

98 UC patients were followed up for a median time of 1.6 years (IQR 0.9¬2.7). Milan ultrasound criteria and Mayo endoscopic subscore significantly correlated at baseline (ρ = 0.653; p < 0.001). 70 patients (71%) had negative disease course during the follow‐up period. Milan ultrasound criteria > 6.2 at baseline was statistically significantly associated with negative disease course (HR: 3.87, 95% CI: 2.25–6.64, p < 0.001). Kaplan–Meier analyses drawed a statistically significantly lower cumulative probability of treatment escalation, need of corticosteroids, hospitalization and colectomy, among patients who had MUC ≤ 6.2 at baseline as compared to patients with MUC > 6.2 (p < 0.05 for all outcomes).

Conclusion

we have demonstrated for the first time the value of bowel US and an US score in predicting disease course in UC. Milan ultrasound criteria, a validated US‐based score, predicts disease course in UC. Milan ultrasound criteria ≤ 6.2 may be the new treatment target to achieve to reduce the risk of worse outcomes.

Ultrasonography in inflammatory bowel disease - So far we are?

Intestinal ultrasound (IUS) is a non‐invasive and accurate tool to assess inflammatory bowel disease. The ECCO‐ESGAR guideline recommends the use of IUS for the assessment of disease activity and complications in Crohn's disease (CD). In addition, an increasing body of evidence suggests the use of IUS as alternative to colonoscopy in monitoring CD and in assessing disease activity of ulcerative colitis. Early responsiveness of IUS findings by the first weeks of treatment and the advantage to perform the procedure in real time may dramatically change frequency of the assessment of treatment response in the future and speed up the clinical decision‐making process. Development of validated and reproducible sonographic scores to measure disease activity and therapeutic response and spread of knowledge of IUS remain relevant issues for the future in which current researchers and the International Bowel Ultrasound (IBUS) Group are actively engaged.

Cross-Sectional Imaging Instead of Colonoscopy in Inflammatory Bowel Diseases: Lights and Shadows

International guidelines recommend a treat-to-target strategy with a close monitoring of disease activity and therapeutic response in inflammatory bowel diseases (IBD). Colonoscopy (CS) represents the current first-line procedure for evaluating disease activity in IBD. However, as it is expensive, invasive and poorly accepted by patients, CS is not appropriate for frequent and repetitive reassessments of disease activity. Recently, cross-sectional imaging techniques have been increasingly shown as reliable tools for assessing IBD activity. While computed tomography (CT) is hampered by radiation risks, routine implementation of magnetic resonance enterography (MRE) for close monitoring is limited by its costs, low availability and long examination time. Novel magnetic resonance imaging (MRI)-based techniques, such as diffusion-weighted imaging (DWI), can overcome some of these weaknesses and have been shown as valuable options for IBD monitoring. Bowel ultrasound (BUS) is a noninvasive, highly available, cheap, and well accepted procedure that has been demonstrated to be as accurate as CS and MRE for assessing and monitoring disease activity in IBD. Furthermore, as BUS can be quickly performed at the point-of-care, it allows for real-time clinical decision making. This review summarizes the current evidence on the use of cross-sectional imaging techniques as cost-effective, noninvasive and reliable alternatives to CS for monitoring patients with IBD.

Unmet needs in inflammatory bowel disease

Despite the recent developments in the diagnosis and management of inflammatory bowel diseases (IBD), patients still suffer from disabling bowel symptoms and significant disease complications and many questions remain to improve their care. IBD is a chronic disease, whose management could be divided into the five different stages of chronic diseases, ranging from the pre-treatment evaluation phase to the induction therapy, maintenance therapy, monitor and re-establishment of control and the cessation of the disease. Reconciling these phases with the current unmet needs in IBD could help tailor priorities for research. In this review, some of the unanswered questions in the management of both Crohn’s Disease and Ulcerative Colitis will be addressed, by following this paradigm of chronic diseases’ management.

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.

Defining Transabdominal Intestinal Ultrasound Treatment Response and Remission in Inflammatory Bowel Disease: Systematic Review and Expert Consensus Statement

BACKGROUND AND AIMS

No consensus exists on defining intestinal ultrasound response, transmural healing, or transmural remission in inflammatory bowel disease, nor clear guidance for optimal timing of assessment during treatment. This systematic review and expert consensus study aimed to define such recommendations, along with key parameters included in response reporting.

METHODS

Electronic databases were searched from inception to July 26, 2021, using pre-defined terms. Studies were eligible if at least two intestinal ultrasound [IUS] assessments at different time points during treatment were reported, along with an appropriate reference standard. The QUADAS-2 tool was used to examine study-level risk of bias. An international panel of experts [n = 18] rated an initial 196 statements [RAND/UCLA process, scale 1-9]. Two videoconferences were conducted, resulting in additional ratings of 149 and 13 statements, respectively.

RESULTS

Out of 5826 records, 31 full-text articles, 16 abstracts, and one research letter were included; 83% [40/48] of included studies showed a low concern of applicability, and 96% [46/48] had a high risk of bias. A consensus was reached on 41 statements, with clear definitions of IUS treatment response, transmural healing, transmural remission, timing of assessment, and general considerations when using intestinal ultrasound in inflammatory bowel disease.

CONCLUSIONS

Response criteria and time points of response assessment varied between studies, complicating direct comparison of parameter changes and their relation to treatment outcomes. To ensure a unified approach in routine care and clinical trials, we provide recommendations and definitions for key parameters for intestinal ultrasound response, to incorporate into future prospective studies.

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.

Role of Intestinal Ultrasound in the Management of Patients with Inflammatory Bowel Disease

Intestinal ultrasound (IUS) has gained popularity as a first line technique for the diagnosis and monitoring of patients with inflammatory bowel diseases (IBD) due to its many advantages. It is a non-invasive imaging technique with non-ionizing radiation exposure. It can be easily performed not only by radiologists but also by trained gastroenterologists at outpatient clinics. In addition, the cost of IUS equipment is low when compared with other imaging techniques. IUS is an accurate technique to detect inflammatory lesions and complications in the bowel in patients with suspected or already known Crohn’s disease (CD). Recent evidence indicates that IUS is a convenient and accurate technique to assess extension and activity in the colon in patients with ulcerative colitis (UC), and can be a non-invasive alternative to endoscopy. In patients with IBD, several non-specific pathological ultrasonographic signs can be identified: bowel wall thickening, alteration of the bowel wall echo-pattern, loss of bowel stratification, increased vascularization, decreased bowel peristalsis, fibro-fatty proliferation, enlarged lymph nodes, and/or abdominal free fluid. Considering the transmural CD inflammation, CD complications such as presence of strictures, fistulae, or abscesses can be detected. In patients with UC, where inflammation is limited to mucosa, luminal inflammatory ultrasonographic changes are similar to those of CD. As the technique is related to the operator’s experience, adequate IUS training, performance in daily practice, and a generalized use of standardized parameters will help to increase its reproducibility.