Ultrasonographic assessment of colonic wall in moderate-severe ulcerative colitis: comparison with endoscopic findings

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.

Selected Cytokines and Metalloproteinases in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a collective term for two diseases: ulcerative colitis (UC) and Crohn's disease (CD). There are many factors, e.g., genetic, environmental and immunological, that increase the likelihood of these diseases. Indicators of IBDs include extracellular matrix metalloproteinases (MMPs). The aim of this review is to present data on the role of selected cytokines and metalloproteinases in IBD. In recent years, more and more transcriptomic studies are emerging. These studies are improving the characterization of the cytokine microenvironment inside inflamed tissue. It is observed that the levels of several cytokines are consistently increased in inflamed tissue in IBD, both in UC and CD. This review shows that MMPs play a major role in the pathology of inflammatory processes, cancer, and IBD. IBD-associated inflammation is associated with increased expression of MMPs and reduced ability of tissue inhibitors of metalloproteinases (TIMPs) to inhibit their action. In IBD patients in tissues that are inflamed, MMPs are produced in excess and TIMP activity is not sufficient to block MMPs. This review is based on our personal selection of the literature that was retrieved by a selective search in PubMed using the terms "Inflammatory bowel disease" and "pathogenesis of Inflammatory bowel diseases" that includes systematic reviews, meta-analyses, and clinical trials. The involvement of the immune system in the pathophysiology of IBD is reviewed in terms of the role of the cytokines and metalloproteinases involved.

Point-of-Care Intestinal Ultrasound in Pediatric Inflammatory Bowel Disease

PURPOSE OF REVIEW

Intestinal ultrasound (IUS) is an emerging non-invasive point-of-care tool utilized by pediatric gastroenterologists for accurately detecting and monitoring inflammatory bowel disease (IBD) activity. In this article, we reviewed the evidence supporting and technique to perform IUS for children with IBD.

RECENT FINDINGS

IUS technique can visualize the colon from the distal sigmoid until the cecum and the terminal ileum without the need for bowel preparation, fasting, or sedation in children with IBD. IUS has been shown to be accurate to endoscopy in children with ulcerative colitis and Crohn's disease. IUS may be the most accurate biomarker to follow as a marker of treatment response that is predictive of endoscopic outcomes in children with IBD. Multiple studies have demonstrated that IUS can be performed at the point-of-care for IBD activity assessment in children. Recent studies have demonstrated the accuracy of IUS to endoscopy and magnetic resonance enterography with an ability to be repeated as a monitor of treatment response for tight control monitoring.

The Role of Noninvasive Surrogates of Inflammation in Monitoring Pediatric Inflammatory Bowel Diseases: The Old and the New

Effectiveness of limited available therapies for pediatric inflammatory bowel disease has reached stagnation. Previous non-invasive monitoring strategies have relied upon cumbersome tools to evaluate clinical symptoms and biochemical markers that do not reflect endoscopic activity or respond quickly to treatments. Novel, patient-centric, and highly accurate, monitoring strategies with a focus on intestinal ultrasound for a direct, precise monitoring of activity to achieve disease modification are now possible. Ultimately, research on the optimal tight control monitoring strategies, individualized to each pediatric inflammatory bowel disease patient, are in development and offer a hope to potential therapeutic ceiling breakthrough on the horizon.

Basic practices for gastrointestinal ultrasound

The standard diagnostic modalities for gastrointestinal (GI) diseases have long been endoscopy and barium enema. Recently, trans-sectional imaging modalities, such as computed tomography and magnetic resonance imaging, have become increasingly utilized in daily practice. In transabdominal ultrasonography (US), the bowel sometimes interferes with the observation of abdominal organs. Additionally, the thin intestinal walls and internal gas can make structures difficult to identify. However, under optimal US equipment settings, with identification of the sonoanatomy and knowledge of the US findings of GI diseases, US can be used effectively to diagnose GI disorders. Thus, the efficacy of GIUS has been gradually recognized, and GIUS guidelines have been published by the World Federation for Ultrasound in Medicine and Biology and the European Federation of Societies for Ultrasound in Medicine and Biology. Following a systematic scanning method according to the sonoanatomy and precisely estimating the layered wall structures by employing color Doppler make diagnosing disease and evaluating the degree of inflammation possible. This review describes current GIUS practices from an equipment perspective, a procedure for systematic scanning, typical findings of the normal GI tract, and 10 diagnostic items in an attempt to help medical practitioners effectively perform GIUS and promote the use of GIUS globally.

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.

The Use of Transabdominal Ultrasound in Inflammatory Bowel Disease

Transabdominal ultrasound (TAUS) is useful in all aspects of lesion screening, monitoring activity, or treating/diagnosing any related complications of inflammatory bowel disease. Its ability to screen or diagnose complications is almost the same as that of other methods, such as CT or MRI. Moreover, its noninvasiveness makes it a first-line examination method. A TAUS image depicting ulcerative colitis will show large intestinal wall thickening that is continuous from the rectum, which is mainly due to mucosal layer thickening, while for Crohn’s disease, a TAUS image is characterized by a diversity in the areas affected, distribution, and layer structure. Indicators of activity monitoring include wall thickness, wall structure, and vascular tests that use Doppler ultrasound or contrast agents. While all of these have been reported to be useful, at this time, no single parameter has been established as superior to others; therefore, a comprehensive evaluation of these parameters is justified. In addition, evaluating the elasticity of lesions using elastography is particularly useful for distinguishing between fibrous and inflammatory stenoses. However, the lack of objectivity is the biggest drawback of using ultrasound. Standardizing and popularizing the ultrasound process will be necessary, including scanning methods, equipment settings, and image analysis.

Transmural Response and Transmural Healing Defined by Intestinal Ultrasound: New Potential Therapeutic Targets?

BACKGROUND AND AIMS

Intestinal ultrasound [IUS] is a useful modality to monitor patients with inflammatory bowel disease [IBD]. Little is known about the use of IUS and appropriate definitions for transmural response [TR] and healing [TH]. We aimed to establish the use of IUS in monitoring TH as a potential target in routine medical practice.

METHODS

Based on the prospective, non-interventional, multicentre studies TRUST and TRUST&UC, we conducted a post-hoc analysis of 351 IBD patients with increased bowel wall thickness [BWT]. We analysed the rates of patients achieving TR and TH, comparing three definitions of TH. In 137 Crohn's disease [CD] patients, the predictive value of TR and TH was investigated for the clinical and sonographic outcome at week 52.

RESULTS

Within 12 weeks of treatment intensification, 65.6% [n = 118] of CD patients and 76.6% [n = 131] of ulcerative colitis [UC] patients showed a TR. Depending on the definition, 23.9-37.2% [n = 58/67/43] of CD patients and 45.0-61.4% [n = 90/105/77] of UC patients had TH at week 12. CD patients with TH were more likely to reach clinical remission at week 12 (odds ratio [OR] 3.33 [1.09-10.2]; p = 0.044) and a favourable sonographic outcome (OR 5.59 [1.97-15.8]; p = 0.001) at week 52 compared with patients without TH.

CONCLUSIONS

IUS response and TH in a relevant proportion of patients suggests that IUS is a useful method to assess transmural inflammatory activity in daily clinical practice. TR and TH are predictive for the sonographic outcome at week 52.

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.

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.

Intestinal Ultrasound to Assess Disease Activity in Ulcerative Colitis: Development of a novel UC-Ultrasound Index

INTRODUCTION

Intestinal ultrasound [IUS] is useful to assess inflammation in ulcerative colitis [UC] patients. We aimed to develop an ultrasonographic activity index using endoscopy as the reference standard.

METHODS

Patients were included consecutively. IUS was performed within 3 weeks from endoscopy. IUS parameters and endoscopy were compared for each colonic segment [except the rectum]. The best parameters were used to construct a UC-IUS index, which was correlated with endoscopic disease activity using the Spearman's rank test.

RESULTS

In 60 patients, 207 colonic segments were evaluated endoscopically. Bowel wall thickness [BWT] > 2.1 mm was optimal to discriminate between Mayo 0 and Mayo 1-3 (sensitivity 82.6%; specificity 93.0%; area under the curve [AUC] 0.910), a cut-off of 3.2 mm was optimal to discriminate between Mayo 0-1 and Mayo 2-3 [sensitivity 89.1%; specificity 92.3%; AUC 0.946] and BWT > 3.9 mm was optimal for detection of Mayo 3 [sensitivity 80.6%; specificity 84.1%; AUC 0.909]. The presence of colour Doppler signal [CDS] predicted active disease, stretches of CDS were associated with Mayo 2-3, lack of haustrations predicted active disease and fat wrapping was associated with severe disease. Inter- and intra-rater intraclass correlation for BWT was substantial. Inter-rater agreement for CDS was substantial and ranged from slight to substantial for haustrations. Intra-rater agreement for CDS was substantial and ranged from moderate to almost perfect for haustrations. The index showed strong correlation with endoscopic disease activity [Mayo: ρ 0.830; p < 0.001, UCEIS: ρ 0.759; p < 0.001].

CONCLUSION

We developed an UC-IUS index which showed strong correlation with endoscopic disease activity using internal validation. It is currently being validated in 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.

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

Introduction

The aim of this study was to provide an external validation of bowel ultrasound (US) predictors of activity in ulcerative colitis (UC) and quantitative Milan Ultrasound Criteria (MUC).

Methods

Forty‐three consecutive patients with UC (16 in endoscopic remission and 27 with endoscopic activity) underwent bowel US and colonoscopy in a tertiary referral inflammatory bowel disease unit.

Results

An MUC score >6.2 discriminated patients with active versus non‐active UC with a sensitivity of 0.85 (95% confidence interval (CI) 0.66–0.96), specificity of 0.94 (95% CI 0.70–0.99) and an area under the curve of 0.902 (95% CI 0.772–0.971) in complete agreement with the derivation study.

Conclusion

The external validation of MUC confirms that it is an accurate tool for assessing disease activity in patients with UC.

Point-of-Care Ultrasound in Inflammatory Bowel Disease

Inflammatory bowel diseases [IBD], including Crohn's disease [CD] and ulcerative colitis [UC], are chronic, relapsing and destructive inflammatory disorders of the gastrointestinal tract which can lead to organ damage and impair quality of life. A 'treat-to-target' strategy based on activity and severity of disease and response to treatment with close monitoring of intestinal inflammation is recommended. Ileocolonoscopy [CS] is considered the first-line procedure for the assessment of IBD, and magnetic resonance enterography [MRE] is the current standard for assessing the small bowel and complications in CD, and has been proposed as an alternative procedure to CS in the evaluation of both ileo-colonic CD and UC. As that both CS and MRE are invasive and expensive procedures and unappealing to patients, they are unfeasible as frequent and repetitive tools for the monitoring of disease activity. Bowel ultrasound [US] represents a well-tolerated, non-invasive and cost-effective modality to manage IBD patients in clinical practice. Compared to CS and MRE, bowel US has been shown to have the same level of accuracy in assessing and monitoring disease activity and severity of both CD and UC. It can be performed at the point-of-care and therefore allow for real-time clinical decision-making. Point-of-care ultrasound [POCUS] is suggested as the stethoscope of the future and is gaining interest and diffusion in the medical field because it can be used for the bedside examination of patients. The aim of this review is to discuss point-of-care bowel ultrasound [POCBUS] in the management of patients with IBD.

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.

Color Doppler Ultrasound Assessment of Clinical Activity in Inflammatory Bowel Disease

BACKGROUND

Ulcerative colitis (UC) and Crohn's disease (CD) are two varieties of inflammatory bowel disease (IBD). Clinicians need a monitoring technique in the IBD. The disease activity can be assessed with endoscopy, activity indexes, and imaging techniques. Color Doppler US (CDUS) is also a non-invasive, radiation, and contrast material free examination which shows the intramural blood flow.

OBJECTIVE

To evaluate the usefulness of B-mode, CDUS, and a newly developed software Color Quantification (CQ) to determine the activity of the IBD.

METHODS

The disease activity was assessed by clinical activity indexes. Caecum, terminal ileum, ascending colon, transverse colon, and descending colon were evaluated by B-mode, CDUS, and the CQ. Bowel wall thickness (BWT), loss of bowel stratification, loss of haustration, and the presence of enlarged lymph nodes, mesenteric masses, abscesses, fistula, visual vascular signal patterns of the bowel as "hypo and hyper-flow" and the CQ values were investigated. BWT was compared with laboratory results and clinical activities. Vascular signal patterns and the CQ values were compared with BWT and clinical activity. The diagnostic performances of the CQ were investigated.

RESULTS

Fifty-two patients with IBD were evaluated. Patients with increased BWT at the transverse colon had an increased frequency of "hyper-flow" pattern. Clinically active patients had an increased incidence of "hyper-flow" pattern at the terminal ileum, ascending colon, and whole segments. They had increased CQ values at the terminal ileum, ascending colon, and descending colon, and whole segments. A cut-off value for the CQ (24.7%) was obtained at the terminal ileum. In the diagnostic performances of CQ, we observed utilities significantly at the ascending colon, descending colon, terminal ileum, and whole segments. There was a positive correlation between the CQ values and BWT at the caecum, ascending colon, transverse colon, and descending colon.

CONCLUSION

Increased visual vascular signal scores and CQ values might be useful for monitoring the disease activity in patients with IBD.

Recommendations of the Spanish Working Group on Crohn's Disease and Ulcerative Colitis (GETECCU) on the use of abdominal ultrasound in inflammatory bowel disease

Ultrasound has an excellent diagnostic performance when Crohn's disease is suspected, when performing an activity assessment, or determining the extension and location of Crohn's disease, very similar to other examinations such as MRI or CT. It has a good correlation with endoscopic lesions and allows the detection of complications such as strictures, fistulas or abscesses. It complements colonoscopy in the diagnosis and, given its tolerance, cost and immediacy, it can be considered as a good tool for disease monitoring. In ulcerative colitis, its role is less relevant, being limited to assessing the extent and activity when it is not possible with other diagnostic techniques or if there are doubts with these. Despite its advantages, its use in inflammatory bowel disease (IBD) is not widespread in Spain. For this reason, this document reviews the advantages and disadvantages of the technique to promote knowledge about it and implementation of it in IBD Units.

Assessing Severity of Disease in Patients with Ulcerative Colitis

Ulcerative colitis (UC) is a chronic disease that can present at various stages of disease activity and severity. Traditionally, severity scoring has focused on disease activity during a single moment with various tools, including patient-reported symptoms, as well as clinical, laboratory-based, endoscopic, histologic, and imaging variables. Optimal delivery of care depends on the accurate assessment of disease severity, which must take longitudinal variables into account. This article reviews the history of severity scoring in UC and provides a concise, clinically oriented approach to assessing disease severity.

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.

Systematic Review: Clinical Utility of Gastrointestinal Ultrasound in the Diagnosis, Assessment and Management of Patients With Ulcerative Colitis

BACKGROUND AND AIMS

Gastrointestinal ultrasound is useful in the assessment of patients with Crohn's disease, but its application in ulcerative colitis [UC] is less well established. Here we systematically review the role of gastrointestinal ultrasound in patients with UC.

METHODS

Searches of the PUBMED and EMBASE databases were performed with the following search strategy: [ultrasound OR sonography] AND [intestinal OR bowel] AND [ulcerative colitis OR inflammatory bowel disease]. The final search was performed in August 2019.

RESULTS

Of 6769 studies identified in the search with a further two studies found from other sources, 50 studies met the inclusion criteria. Increased bowel wall thickness and detection of increased blood flow by colour Doppler were the most often applied criteria for defining disease activity and distribution. When compared with other reference investigations, gastrointestinal ultrasound accurately determined disease extent, severity and response to medical therapy. While further information can be obtained from haemodynamic measurements of the abdominal vessels and contrast-enhanced ultrasound, their clinical value was uncertain. Likewise, hydrocolonic sonography has few advantages over standard gastrointestinal ultrasound examination. Of several scoring systems proposed, there is disparity between the measures and a general lack of validation. There has been limited application of gastrointestinal ultrasound in acute severe ulcerative colitis with toxic megacolon, and, while performing well in children, normal limits differ from those in adults.

CONCLUSION

Current evidence indicates that gastrointestinal ultrasound has utility in the non-invasive assessment of patients with UC. Continued advances in technology with better image resolution, validation of scoring systems and application at the point of care by gastroenterologists are likely to contribute to increased use of gastrointestinal ultrasound in routine clinical practice.

Use of Cross-Sectional Imaging for Tight Monitoring of Inflammatory Bowel Diseases

A treat-to-target strategy with close monitoring of intestinal inflammation is recommended in inflammatory bowel disease (IBD). Ileocolonoscopy remains the gold standard for assessing disease activity in IBD but is a relatively invasive procedure and is impossible to repeat in the context of tight monitoring strategies. In addition to biomarkers, cross-sectional imaging increasingly is used in these patients. Computed tomography is limited by the use of radiation, while the use of magnetic resonance enterography (MRE) is limited by its cost and access. There is growing interest in bowel ultrasound that represents a cost-effective, noninvasive, and well-tolerated modality in clinical practice, but it is operator dependent. Compared with ileocolonoscopy and MRE, bowel US has been shown to have the same level of accuracy in assessing and monitoring disease activity for both CD and UC and thus can be considered a point-of-care test. Diffusion-weighted imaging (DWI) is a MR imaging technique that increasingly is used in both IBD and non-IBD conditions and has been shown to be a valuable and accurate tool for assessing and monitoring IBD activity. Compared with conventional MRE, DWI is quicker, less time consuming, may not require intravenous contrast agent, fasting, bowel cleansing, oral preparation, or rectal preparation. This review discusses the role of these cross-sectional imaging techniques for the management of patients with IBD. In the near future, the value of DWI and ultrasound in assessing IBD will require further investigation in the era of transmural healing in CD and complete mucosal healing, including histologic remission, in ulcerative colitis.

Usefulness of transabdominal ultrasonography for assessing ulcerative colitis: a prospective, multicenter study

BACKGROUND

Transabdominal ultrasonography (US) has been reported to be a useful tool for evaluating ulcerative colitis (UC) although with less well-established data than for Crohn's disease. This prospective multicenter study aimed to establish the usefulness of US compared with colonoscopy (CS) for assessing disease extent and activity of UC.

METHODS

Altogether, 173 patients with UC were prospectively enrolled, among whom 156 were eligible for this study. All patients underwent US and CS within 2 days at five facilities. We divided the colon into six segments and examined each segment and the rectum using US and CS. US severity was graded 1-4 regarding bowel wall thickness, stratification, and ulceration. CS severity was also graded 1-4 according to Matts' endoscopic classification. Concordance between US and CS grades for all colonic segments was analyzed using kappa statistics. US and CS findings were also compared with the clinical disease activity index (CAI) and histological grade using Spearman's correlation coefficient.

RESULTS

There was moderate concordance between US and CS grades in all colonic segments (weighted κ = 0.55, p < 0.001). Concordance was rated moderate for each colonic segment but only slight for the rectum. The US grade was significantly correlated with the CAI score (r = 0.40, p < 0.001) and histological grade (r = 0.35, p < 0.001).

CONCLUSIONS

This prospective multicenter study showed moderate concordance between US and CS for assessing the disease activity of UC. Hence, US may be used more generally for evaluating UC in daily clinical practice.

Ultrasonography of the colon in pediatric ulcerative colitis: a prospective, blind, comparative study with colonoscopy

OBJECTIVES

To evaluate the usefulness of colonic ultrasonography (US) in assessing the extent and activity of disease in pediatric ulcerative colitis (UC) and to compare US findings with clinical and endoscopic features.

STUDY DESIGN

Consecutive pediatric patients (n = 60) with a diagnosis of UC and suspected disease flare-up were prospectively enrolled; of these, 50 patients were eligible for the study. All underwent clinical evaluation, bowel US with color Doppler examination and colonoscopy. Blind US was performed the day before endoscopy in all patients. The US assessed variables were bowel wall thickness >3 mm, bowel wall stratification, vascularity, presence of haustra coli, and enlarged mesenteric lymph nodes.

RESULTS

The endoscopic extent of disease was independently confirmed in 47 patients by US that yielded a 90% concordance with endoscopy (95% CI 0.82-0.96). Multiple regression analysis showed that US measurements with an independent predictive value of severity at endoscopy were increased bowel wall thickness (P < .0008), increased vascularity (P < .002), loss of haustra (P = .031), and loss of stratification of the bowel wall (P = .021). Each variable was assigned a value of 1 if present. The US score strongly correlated with clinical (r = 0.94) and endoscopic activity (r = 0.90) of disease (P < .0001).

CONCLUSIONS

Colonic US is a useful first line noninvasive tool to assess the extent and activity of disease in children with UC and to estimate the severity of a flare-up, prior to further invasive tests.

Increased wall thickness using ultrasonography is associated with inflammation in an animal model of experimental colitis

Experimentally induced colitis is used in animals to investigate pathophysiological mechanisms in inflammatory bowel disease. When following disease course and treatment effects, it should be possible to perform repeated measurements without harming the animals. This pilot study was performed to investigate whether transabdominal ultrasound using a clinical scanner could be used on rats to demonstrate bowel inflammation in an experimental colitis model. Colitis was induced by either 5% dextran sodium sulfate (DSS) in drinking water for 7 days or a single dose of intracolonic trinitrobenzene sulfonic acid (TNBS). Using ultrasonography, wall thickness of distal colon, cecum, and small bowel was recorded prior to and after DSS, and prior to, 2, and 7 days after TNBS. Blood (tumor necrosis factor [TNF]-alpha) and fecal samples (HemoFEC occult blood) were taken from each group on the same days as sonography. Thereafter, rats were killed and specimens for histology were taken. Wall thickness of distal colon, not of cecum or small bowel, increased significantly after 7 days of DSS, and wall thickness of both distal colon and small bowel increased on day 2 and 7 after TNBS. TNF-alpha increased after 7 days in the latter group only. There was a significant correlation between ultrasonographic measurements and combined histology score of distal colon in the DSS group. HemoFEC was also positive in accordance with sonographic and histological features. Increased intestinal wall thickness in response to both DSS- and TNBS-induced colitis was able to be visualized by transabdominal sonography. Moreover, ultrasound findings, occult blood sampling, and histological findings supported each other, indicating that ultrasonography can be used to assess inflammation in a rat experimental model.