Diagnostic Accuracy of Ultrasonography in the Detection of Postsurgical Recurrence in Crohn's Disease: A Systematic Review with Meta-analysis

Outcomes and Endpoints of Postoperative Recurrence in Crohn's Disease: Systematic Review and Consensus Conference

BACKGROUND

Outcomes after ileocolonic resection in Crohn's disease [CD] are heterogeneous, and a clear definition of postoperative recurrence remains to be determined. Our Endpoints Working Group of the International Organization for the study of Inflammatory Bowel Disease [IOIBD] aimed to standardise postoperative outcomes, to discuss which endpoints should be used for postoperative clinical trials, and to define those which could be used in trials or registries.

METHODS

Based on a systematic review of the literature, recommendations and statements were drafted and sent to all IOIBD members for a first round of voting. Recommendations and statements were revised based on the voters' comments during a consensus hybrid conference open to all IOIBD members. If no agreement was reached after two rounds of voting, the statement was excluded.

RESULTS

In the systematic review, 3071 manuscripts were screened of which 434 were included. Sixteen recommendations were identified, of which 11 were endorsed. Recommendations and statements include that endoscopy remains the gold standard and should be used as a short-term primary endpoint in both observational cohorts and randomised controlled trials. Clinical symptoms classically used in clinical trials for luminal CD are not reliable in this specific situation. For that reason, longer-term endpoints should be based on the evidence of macroscopic inflammation assessed by imaging techniques, endoscopy, or as reflected by the presence of complications.

CONCLUSIONS

Agencies recommend the use of clinical evaluations, as in the case of luminal CD, and do not recognise primary endpoints based solely on endoscopy. This consensus has led to agreement on the need to define postoperative endoscopy-based and/or imaging-based endpoints.

Diagnostic value of MR and CT enterography in post-operative recurrence of Crohn's disease: a systematic review and meta-analysis

Post-operative recurrence is a critical issue in the surveillance of Crohn's disease after ileocecal resection. This meta-analysis aims to assess the diagnostic yield of enterography techniques in post-operative recurrence of Crohn's disease. A systematic electronic bibliographic databases search was conducted. The inclusion criteria of original articles were: Utilized MR enterography or CT enterography after ileocolonic resection; Documented recurrence by ileo-colonoscopy (Rutgeerts' score ≥ i2); Provided crude data of diagnostic performance. A random-effect method was used for analysis. Relative risk and diagnostic value of each imaging feature were calculated. Eleven studies (11 populations and 589 patients) were included (4 CTE and 7 MRE with 248 and 341 patients, respectively). The pooled sensitivity and specificity of the enterography were 91% (95% CI: 0.85-0.95) and 75% (95% CI: 0.56-0.87), respectively. The pooled sensitivity and specificity of CTE were 93% (95% CI: 0.87-0.96) and 67% (95% CI: 0.35-0.90), respectively. MRE revealed pooled sensitivity and specificity of 90% (95% CI: 0.78-0.96) and 78% (95% CI: 0.57-0.90), respectively. The inter-study heterogeneity was low for sensitivity (I2 = 29%, p-value = 0.17) and high for specificity (I2 = 85%, p-value < 0.01). Wall enhancement, anastomosis wall thickening, anastomosis stenosis, pre-anastomotic dilatation, penetrating lesion, comb sign, and perivisceral edema were significantly higher in POR patients. Wall thickening and penetrating lesion were the most sensitive (81%) and specific (97%) findings, respectively. MRE and CTE exhibit high sensitivity and acceptable specificity (especially MRE) for detection of recurrence in Crohn's disease which makes them an effective initial screening tool and reserves ileo-colonoscopy for those patients with inconclusive enterography results.

Postoperative small bowel Crohn's disease: how to diagnose, manage and treat

PURPOSE OF REVIEW

Crohn's disease is a relapsing inflammatory condition and disease recurrence after surgery is common. Significant variation in clinical practice remains despite progress in management of postoperative Crohn's disease. In this review, we summarise current management strategies and guidelines, unmet needs, and research progress in this field.

RECENT FINDINGS

There has been real progress in risk stratifying individuals' postsurgery and tailoring therapies based on their risk; this has been incorporated into current management guidelines in the USA, UK, and Europe. Furthermore, novel noninvasive monitoring tools such as intestinal ultrasound have shown high sensitivity and specificity at detecting disease recurrence and are an attractive point-of-care test. Recent studies are also investigating multiomic biomarkers to prognosticate postoperative Crohn's disease. However, given the heterogeneity within this condition, large multicentre clinical validation across all age groups is needed for clinical translation in the future.

SUMMARY

Ongoing progress in research and the development of novel prognostic and noninvasive disease monitoring tools offers hope for personalised therapy tailored to individual recurrence risk in postoperative Crohn's disease.

Clinical Update on the Prevention and Management of Postoperative Crohn's Disease Recurrence

PURPOSE OF REVIEW

Despite advances in therapeutics, a significant portion of patients with Crohn's disease still require surgical management. In this article, we present updates to the natural history, prognostication and postoperative monitoring, and novel therapeutics in the prevention and treatment of postoperative Crohn's disease recurrence.

RECENT FINDINGS

Clinical risk factors have been associated with higher rates of postoperative recurrence (POR), and in recent studies demonstrate an increased cumulative risk with presence of additional risk factors. Additional novel clinical, histologic, and "-omic" risk factors for recurrence have recently been elucidated, including the role of the mesentery on recurrence and perioperative intraabdominal septic complications. High-risk patients benefit most from medical prophylaxis, including anti-TNF with or without immunomodulator therapy to prevent recurrence. New biologics such as vedolizumab and ustekinumab have emerging evidence in the use of prophylaxis, especially with recent REPREVIO trial data. Non-invasive disease monitoring, such as cross-sectional enterography, intestinal ultrasound, and fecal calprotectin, have been validated against ileocolonoscopy. Recent advances in the prediction, prevention, and monitoring algorithms of postoperative Crohn's disease may be leading to a reduction in postoperative recurrence. Ongoing trials will help determine optimal monitoring and management strategies for this at-risk population.

Intestinal ultrasound in inflammatory bowel disease: New kid on the block

Intestinal ultrasound is an emerging technique for diagnosing and monitoring patients with inflammatory bowel disease (IBD). It is a simple, non-invasive, inexpensive, safe and reliable tool for monitoring patients with IBD. This technique has good diagnostic accuracy in the assessment of the extent and severity of IBD and its complications. The most commonly used parameters are bowel wall thickness, color Doppler flow, bowel wall stratification and peri-bowel inflammation. Various scoring systems have been developed utilizing the above parameters to monitor patients with IBD. It is a good tool to monitor response to therapy and follow-up for post-operative recurrence. Early response on intestinal ultrasound (IUS) predicts long-term clinical remission and mucosal healing in patients with Crohn's disease. In patients with ulcerative colitis (UC), the response to IUS can be assessed as early as two weeks. Recent data has emerged to predict the response to corticosteroids and colectomy in patients with acute severe UC. Point of care IUS in the outpatient clinic is an excellent tool to follow-up patients and guide clinical decision-making and has good acceptability among patients. It is an underutilized technique in spite of its appeal and the availability of evidence. Underutilization can be attributed to the lack of awareness, expertise and training centres. This review discusses the technical details and the evidence to support the use of IUS in IBD. We aim to increase awareness and use of intestinal ultrasound and build local expertise and data.

The Management of Postoperative Recurrence in Crohn's Disease

Crohn's disease (CD) is a chronic inflammatory bowel disease with different phenotypes of presentation, inflammatory, penetrating, or stricturing disease, that significantly impacts patient well-being and quality of life. Despite advances in medical therapy, surgery sometimes represents the only treatment to address complications, such as strictures, fistulas, or abscesses. Minimizing postoperative recurrence (POR) remains a major challenge for both clinicians and patients; consequently, various therapeutic strategies have been developed to prevent or delay POR. The current review outlines an updated overview of POR management. We focused on diagnostic assessment, which included endoscopic examination, biochemical analyses, and cross-sectional imaging techniques, all crucial tools used to accurately diagnose this condition. Additionally, we delved into the associated risk factors contributing to POR development. Furthermore, we examined recent advances in the prophylaxis and treatment of POR in CD.

Small Intestinal Contrast Ultrasonography (SICUS) in Crohn's Disease: Systematic Review and Meta-Analysis

The diagnosis of Crohn's Disease (CD) is based on a combination of clinical symptoms, laboratory tests, endoscopy, and imaging data. In Small Intestine Contrast Ultrasonography (SICUS), the ingestion of a macrogol solution as an oral contrast medium may optimize image quality. We performed a meta-analysis to evaluate the diagnostic performance of SICUS for CD. A literature search was performed in August 2023. We selected only studies where SICUS was compared to a technique that allows the assessment of the whole gastrointestinal tract, such as an MRE, a CT scan, or a surgical evaluation. We estimated pooled weighted sensitivity, specificity, and likelihood ratio for positive and negative tests (PLR/NLR) of SICUS. Summary receiver operating characteristic curves (SROC) were drawn, and pooled areas under the curve (AUC) were calculated. Five studies with 325 CD patients were included. SICUS showed a pooled sensitivity for the diagnosis of 95% (95% confidence interval CI 89-99%), a specificity = 77% (95% CI 60-90%), and the AUC was 0.94. SICUS demonstrated a pooled sensitivity for strictures of 78% (95% CI 63-88%) and a specificity = 96% (95% CI 85-99%), with AUC = 0.93. For abscesses, SICUS demonstrated a pooled sensitivity of 100% (95% CI 59-100%) and a specificity of 90% (95% CI 74-98%). Fistulae were detected with a pooled sensitivity of 77% (95% CI 46-95%) and a specificity of 92% (95% CI 75-99%). SICUS demonstrated excellent diagnostic performance compared to the gold standard despite some clinical scenarios (stenosis/fistulae) showing suboptimal diagnostic effectiveness.

Noninvasive Assessment of Postoperative Disease Recurrence in Crohn's Disease: A Multicenter, Prospective Cohort Study on Behalf of the Italian Group for Inflammatory Bowel Disease

BACKGROUND & AIMS

Colonoscopy (CS) is the gold standard to assess postoperative recurrence (POR) in Crohn's disease (CD). However, CS is invasive and may be poorly tolerated by patients. The aim of this study was to prospectively assess the diagnostic accuracy of a noninvasive approach in detecting POR, using the endoscopic Rutgeerts' score (RS) as the reference standard.

METHODS

Consecutive patients with CD who underwent ileo-cecal resection were prospectively enrolled in 3 referral Italian centers. Patients underwent CS and bowel ultrasound within 1 year of surgery. Uni- and multivariable analyses were used to assess the correlation between noninvasive parameters and endoscopic recurrence, defined by a RS ≥2.

RESULTS

Ninety-one patients were enrolled. Sixty patients (66%) experienced endoscopic POR. The multivariable analysis identified bowel wall thickness (BWT) per 1-mm increase (odds ratio [OR], 2.43; 95% confidence interval [CI], 1.21-4.89; P = .012), the presence of mesenteric lymph nodes (OR, 15.63; 95% CI, 1.48-164.54; P = .022), and fecal calprotectin (FC) values ≥50 mcg/g (OR, 8.58; 95% CI, 2.45-29.99; P < .001) as independent predictors for endoscopic recurrence. The presence of lymph nodes or the combination of BWT ≥3 mm and FC values ≥50 mcg/g correctly classified 56% and 75% of patients, with less than 5% of patients falsely classified as having endoscopic recurrence. Conversely, the combination of BWT <3 mm and FC <50 mcg/g correctly classified 74% of patients with only 4.5% of patients falsely classified as not having endoscopic recurrence.

CONCLUSIONS

A noninvasive approach combining bowel ultrasound and FC can be used with confidence for detecting POR in patients with CD without the requirement for CS.

Results of the Eighth Scientific Workshop of ECCO: Diagnosing Postoperative Recurrence of Crohn's Disease After an Ileocolonic Resection With Ileocolonic Anastomosis

Despite the introduction of potent biologic therapies, many patients with Crohn's disease [CD] still require an ileocolonic resection [ICR] during the course of their disease. Furthermore, the need of redo ICR has not decreased over the past few decades, highlighting the need for better strategies to prevent and treat postoperative recurrence [POR]. The first step to develop such a strategy would be to define and standardise the description of POR with adequate diagnostic instruments. In this article, we will describe the different methodologies used to report POR [endoscopic, histological, radiological, biochemical, clinical, and surgical], and review their potential benefits and limitations, as well as the optimal timing of evaluation.

Recent advances in the use of ultrasound in Crohn's disease

INTRODUCTION

A clear consensus exists on the role of IUS for the assessment and monitoring of Crohn's disease (CD) in the 'treat-to-target' strategy.

AREAS COVERED

IUS is an accurate tool for the management of CD. It is noninvasive and well tolerated. IUS has good-to-optimal inter-operator reliability either for assessing disease activity or for evaluating treatment response, especially combining Bowel Wall Thickness (BWT) and Color Doppler Signals (CDS). IUS is able to evaluate transmural remission (TR), the ultimate goal of the 'treat-to-target' strategy. Several studies confirmed its accuracy in the assessment of the post-operative recurrence (POR). Thanks to recent advances in trans-perineal ultrasound technique (TPUS), it allows to characterize peri-anal disease and its complications. Small intestine contrast ultrasound (SICUS) and contrast-enhancement ultrasound (CEUS) may improve IUS performance, particularly in stricturing or penetrating CD. Ultrasound elastography (USE) is raising interest for its accuracy in differentiating CD phenotypes (fibrotic versus inflamed).

EXPERT OPINION

IUS is a pivotal step in the management of CD, in early assessment as in therapeutic monitoring, with advantages of evaluating transmural response. Development and validation of novel ultrasound biomarkers of activity and fibrosis, especially those linked to advanced ultrasound techniques, are expected in the coming years.

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.

Diagnostic accuracy of different cross-sectional imaging techniques for disease location and activity in Crohn's disease and external validation and comparison of MARIAs and IBUS-SAS

PURPOSE

The comparative accuracy of cross-sectional imaging techniques for evaluating Crohn's disease (CD) remains uncertain. This study aimed to assess diagnostic accuracy of disease location and activity in different cross-sectional images and validate and compare International Bowel Ultrasound Segmental Activity Score (IBUS-SAS) and Simplified Magnetic Resonance Index of Activity (MARIAs).

METHODS

CD patients were retrospectively included from August 2018 to May 2021. We compared accuracy of B-mode intestinal ultrasound (B-IUS), computed tomography enterography (CTE), and magnetic resonance enterography (MRE) for the identification of disease location. Meanwhile, disease activity was compared on B-IUS, color Doppler imaging, CTE, and MRE. ROC analyses were used to validate MARIAs and IBUS-SAS. Spearman rank correlation was performed to evaluate the relationships between MARIAs/IBUS-SAS and CDAI, SES-CD, and inflammatory indicators.

RESULTS

A total of 115 CD patients were evaluated. The diagnostic accuracy of MRE in detecting small bowel disease was superior to that of B-IUS/CTE, showing sensitivity (89.3%), specificity (71.4%), and AUC (0.820). B-IUS had the highest sensitivity (81.2%), specificity (84.8%), and AUC (0.830) for detecting terminal ileal lesions. The diagnostic accuracy for colonic disease and disease activity was not significantly different among these techniques. In the validation of IBUS-SAS, the AUC was 0.860, with an optimal cutoff value to predict active disease of 46.7. MARIAs and IBUS-SAS showed no significant differences in the correlations of CDAI, SES-CD, and inflammatory indicators.

CONCLUSION

MRE and B-IUS are more sensitive for detecting small bowel CD and terminal ileal CD, respectively. IBUS-SAS has potential for precisely defining CD activity.

Use of imaging modalities for decision-making in inflammatory bowel disease

Cross-sectional magnetic resonance enterography (MRE) and intestinal ultrasonography (IUS) provide valuable and noninvasive information to accurately assess disease activity, severity, and extent; detect complications; and monitor the response to treatment, as well as predict the postoperative recurrence of Crohn's disease and a negative disease course. Therefore, both imaging modalities are emerging as pivotal diagnostic tools to achieve the emerging therapeutic target of transmural healing associated with better disease outcomes. Despite its numerous potential advantages over endoscopy and even MRE and its good availability, IUS is still widely underused to monitor and manage inflammatory bowel disease (IBD) patients and help in making clinical decisions in routine practice. This situation is clearly due to the absence of validated, reliable, and responsive indices, as well as the lack of trained gastroenterologists and radiologists, as IUS is a component of radiologist expertise in several countries but not yet integrated into the training program of gastroenterologists. However, there is an increasing body of evidence in the literature that IUS and MRE are both becoming essential imaging resources to help clinicians in making reliable decisions. Here, we discuss the up-to-date evidence about the usefulness and performance of cross-sectional imaging, focusing on the ability of bowel US and MRE to aid clinical decision-making for the optimal management and monitoring of IBD.

Post-operative prevention and monitoring of Crohn's disease recurrence

Crohn's disease (CD) and ulcerative colitis (UC) are relapsing and remitting chronic inflammatory diseases of the gastrointestinal tract. Although surgery for UC can provide a cure, surgery for CD is rarely curative. In the past few decades, research has identified risk factors for postsurgical CD recurrence, enabling patient risk stratification to guide monitoring and prophylactic treatment to prevent CD recurrence. A MEDLINE literature review identified articles regarding post-operative monitoring of CD recurrence after resection surgery. In this review, we discuss the evidence on risk factors for post-operative CD recurrence as well as suggestions on post-operative management.

Contemporary Management of Postoperative Crohn's Disease after Ileocolonic Resection

Surgery remains an important treatment modality in the multidisciplinary management of patients with Crohn's disease (CD). To illustrate the recent advances in the management of postoperative CD we outline the contemporary approach to treatment: diagnosing disease recurrence using endoscopy or noninvasive methods and risk stratification underlying decisions to institute treatment. Endoscopic scoring indices are being refined to guide treatment decisions by accurately estimating the risk of recurrence based on endoscopic appearance. The original Rutgeerts score has been modified to separate anastomotic lesions from lesions in the neoterminal ileum. Two further indices, the REMIND score and the POCER index, were recently developed with the same intention. Noninvasive monitoring for recurrence using a method with high negative predictive value has the potential to simplify management algorithms and only perform ileocolonoscopy in a subset of patients. Fecal calprotectin, intestinal ultrasound, and magnetic resonance enterography are all being evaluated for this purpose. The use of infliximab for the prevention of postoperative recurrence is well supported by data, but management decisions are fraught with uncertainty for patients with previous exposure to biologics. Data on the use of ustekinumab and vedolizumab for postoperative CD are emerging, but controlled studies are lacking.

Intestinal Ultrasound in the Assessment of Luminal Crohn’s Disease

Crohn’s disease is a chronic inflammatory disease affecting the gastrointestinal tract. Expert guidelines now recommend regular objective assessments as part of a treat-to-target approach. Intestinal ultrasound provides a noninvasive, patient-friendly modality for assessing Crohn’s disease without the risk of radiation exposure and does not require fasting or bowel preparation. Enhancement techniques, including oral and intravenous contrast, can improve disease-activity and complication detection. Due to its acceptability, intestinal ultrasound can be performed frequently, allowing for closer disease-activity monitoring and treatment adjustments. There have been significant advances in the utility of intestinal ultrasound; particularly for assessing disease activity during pregnancy and fibrosis detection utilising elastography. This review provides a comprehensive overview of performing intestinal ultrasound, the diagnostic accuracy, role in disease-activity monitoring, and recent advances in utilising ultrasound for the assessment of luminal Crohn’s disease.

Diagnostic Utility of Non-invasive Tests for Inflammatory Bowel Disease: An Umbrella Review

Background

This study aims to consolidate evidence from published systematic reviews and meta-analyses evaluating the diagnostic performances of non-invasive tests for inflammatory bowel disease (IBD) in various clinical conditions and age groups.

Methods

Two independent reviewers systematically identified and appraised systematic reviews and meta-analyses assessing the diagnostic utility of non-invasive tests for IBD. Each association was categorized as adults, children, and mixed population, based on the age ranges of patients included in the primary studies. We classified clinical scenarios into diagnosis, activity assessment, and predicting recurrence.

Results

In total, 106 assessments from 43 reviews were included, with 17 non-invasive tests. Fecal calprotectin (FC) and fecal lactoferrin (FL) were the most sensitive for distinguishing IBD from non-IBD. However, anti-neutrophil cytoplasmic antibodies (ANCA) and FL were the most specific for it. FC and FL were the most sensitive and specific tests, respectively, to distinguish IBD from irritable bowel syndrome (IBS). Anti-Saccharomyces cerevisiae antibodies (ASCA), IgA, were the best test to distinguish Crohn’s disease (CD) from ulcerative colitis (UC). Interferon-γ release assay was the best test to distinguish CD from intestinal tuberculosis (ITB). Ultrasound (US) and magnetic resonance enterography (MRE) were both sensitive and specific for disease activity, along with the high sensitivity of FC. Small intestine contrast ultrasonography (SICUS) had the highest sensitivity, and FC had the highest specificity for operative CD recurrence.

Conclusion

In this umbrella review, we summarized the diagnostic performance of non-invasive tests for IBD in various clinical conditions and age groups. Clinicians can use the suggested non-invasive test depending on the appropriate clinical situation in IBD patients.

Non-invasive Serological Monitoring for Crohn's Disease Postoperative Recurrence

INTRODUCTION

Crohn's disease recurs after intestinal resection. This study evaluated accuracy of a new blood test, the Endoscopic Healing Index [EHI], in monitoring for disease recurrence.

METHODS

Patients enrolled in the prospective POCER study [NCT00989560] underwent a postoperative colonoscopic assessment at 6 [2/3 of patients] and 18 months [all patients] following bowel resection, using the Rutgeerts score [recurrence ≥i2]. Serum was assessed at multiple time points for markers of endoscopic healing using the EHI, and paired with the Rutgeerts endoscopic score as the reference standard.

RESULTS

A total of 131 patients provided 437 serum samples, which were paired with endoscopic assessments available in 94 patients [30 with recurrence] at 6 months and 107 patients [44 with recurrence] at 18 months. The median EHI at 6 months was significantly lower in patients in remission [Rutgeerts <i2] than those with recurrence; p = 0.033. The area under the receiver operating curve [AUROC] for EHI to detect recurrence at 6 months was comparable to that of faecal calprotectin [0.712 vs 0.779, p = 0.414]. EHI of <20 at 6 months had a negative predictive value of 75.7% (95% confidence interval [CI] 58.8-88.2), and sensitivity of 70% [95% CI 50.6-85.3] for detecting recurrence. Combining all time points, an EHI <20 had a negative predictive value of 70.3%. Changes in EHI significantly associated with changes in Rutgeerts scores over the 18 months.

CONCLUSIONS

The non-invasive multi-marker EHI has sufficient accuracy to be used to monitor for postoperative Crohn's disease recurrence. A monitoring strategy that combines EHI with ileocolonoscopy, with or without faecal calprotectin, should now be prospectively tested.

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.

Therapeutic strategies in Crohn’s disease in an emergency surgical setting

Crohn’s disease (CD) remains a chronic, incurable disorder that presents unique challenges to the surgeon. Multiple factors must be considered to allow development of an appropriate treatment plan. Medical therapy often precedes or complements the surgical management. The indications for operative management of CD include acute and chronic disease complications and failed medical therapy. Elective surgery comes into play when patients are refractory to medical treatment if they have an obstructive phenotype. Toxic colitis, acute obstruction, perforation, acute abscess, or massive hemorrhage represent indications for emergency surgery. These patients are generally in critical conditions and present with intra-abdominal sepsis and a preoperative status of immunosuppression and malnutrition that exposes them to a higher risk of complications and mortality. A multidisciplinary team including surgeons, gastroenterologists, radiologists, nutritional support services, and enterostomal therapists are required for optimal patient care and decision making. Management of each emergency should be individualized based on patient age, disease type and duration, and patient goals of care. Moreover, the recurrent nature of disease mandates that we continue searching for innovative medical therapies and operative techniques that reduce the need to repeat surgical operations. In this review, we aimed to discuss the acute complications of CD and their treatment.

Application of transabdominal ultrasound in Crohn's disease

Crohn's disease (CD), a chronic nonspecific intestinal inflammatory disorder of uncertain origin, is collectively referred to as inflammatory bowel disease with ulcerative colitis. In recent years, with the increasing incidence of CD, a greater demand has been put forward for disease diagnosis and inflammatory activity monitoring. With the development of ultrasound technology, transabdominal ultrasound has become more relevant for the diagnosis and follow-up of CD, providing an effective non-invasive examination tool for patients. This review summarizes several transabdominal ultrasound modalities and associated techniques that are presently being developed and utilized in clinical practice, describes the ultrasound manifestations of CD, and discusses the value and prospect of transabdominal ultrasonography in CD.

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.

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.

What's New in the Postoperative Management of Crohn's Disease?

Patients with Crohn's disease (CD) often require surgical resection due to complications, such as strictures and abscesses, or disease refractory to medical therapy. To understand the evolving management of patients with CD after surgery, we outline the risk factors for postoperative recurrence, advances in postoperative endoscopic evaluation and characterization of recurrence, noninvasive methods of assessing postoperative recurrence, use of postoperative prophylactic medical therapy including newer biologics, and novel surgical methods to reduce postoperative recurrence. The Rutgeerts score (RS) was developed to predict progression of disease based on endoscopic appearance postoperatively and to guide medical therapy. However, this scoring system groups ileal and anastomotic lesions into the same category. A modified RS was developed to separate lesions isolated to the anastomosis and those in the neo-terminal ileum to further understand the role of anastomotic lesions in CD progression. Additional scoring systems have also been evaluated to better understand these differences. In addition, noninvasive diagnostic methods, such as small bowel ultrasound, have high sensitivity and specificity for the detection of postoperative recurrence and are being evaluated as independent methods of assessment. Studies have also shown a reduction in endoscopic recurrence with postoperative anti-TNFα therapy. However, preoperative exposure to anti-TNFα therapy may impact postoperative response to these medications, and therefore, determining optimal postoperative prophylaxis strategy for biologic-experienced patients requires further exploration. Lastly, new surgical modalities to reduce postoperative recurrence are currently being investigated with preliminary data suggesting that an antimesenteric functional end-to-end anastomosis (Kono-S) may decrease postoperative recurrence.

Current noninvasive modalities in Crohn's disease monitoring

Crohn’s disease (CD) is characterized by a remitting and relapsing course. Longstanding active CD may result in accumulating intestinal damage and disease-related complications. In contrast, mucosal healing is associated with significant improvement in the health-related quality of life, longer periods of disease remission and lower risk of disease progression, complications, hospitalizations, intestinal surgeries, as well as a lower risk of developing colorectal cancer. Mucosal healing, the new treatment endpoint in CD, made necessary the development of noninvasive, accurate, objective and reliable tools for the evaluation of CD activity. Ileocolonoscopy with biopsies remains the reference standard method for the evaluation of the colonic and terminal ileal mucosa. However, it is an invasive procedure with a low risk of complications, allowing the investigation of only a small part of the small bowel mucosa without being able to assess transmural inflammation. These disadvantages limit its role in the frequent follow up of CD patients. In this review, we present the currently available biomarkers and imaging modalities for the noninvasive assessment of CD activity.

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

Background

Intestinal ultrasound is emerging as a non-invasive tool for monitoring disease activity in inflammatory bowel disease patients due to its low cost, excellent safety profile, and availability. Herein, we comprehensively review the role of intestinal ultrasound in the management of these patients.

Summary

Intestinal ultrasound has a good accuracy in the diagnosis of Crohn's disease, as well as in the assessment of disease activity, extent, and evaluating disease-related complications, namely strictures, fistulae, and abscesses. Even though not fully validated, several scores have been developed to assess disease activity using ultrasound. Importantly, intestinal ultrasound can also be used to assess response to treatment. Changes in ultrasonographic parameters are observed as early as 4 weeks after treatment initiation and persist during short- and long-term follow-up. Additionally, Crohn's disease patients with no ultrasound improvement seem to be at a higher risk of therapy intensification, need for steroids, hospitalisation, or even surgery. Similarly to Crohn's disease, intestinal ultrasound has a good performance in the diagnosis, activity, and disease extent assessment in ulcerative colitis patients. In fact, in patients with severe acute colitis, higher bowel wall thickness at admission is associated with the need for salvage therapy and the absence of a significant decrease in this parameter may predict the need for colectomy. Short-term data also evidence the role of intestinal ultrasound in evaluating therapy response, with ultrasound changes observed after 2 weeks of treatment and significant improvement after 12 weeks of follow-up in ulcerative colitis.

Key Messages

Intestinal ultrasound is a valuable tool to assess disease activity and complications, and to monitor response to therapy. Even though longer prospective data are warranted, intestinal ultrasound may lead to a change in the paradigm of inflammatory bowel disease management as it can be used in a point-of-care setting, enabling earlier intervention if needed.

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.

Comparison of transmural healing and mucosal healing as predictors of positive long-term outcomes in Crohn's disease

BACKGROUND

Transmural healing (TH) is being increasingly recognized for reflecting deep remission in Crohn's disease (CD). The long-term clinical significance of achieving TH is still not fully known. We aimed to evaluate TH as a predictor of long-term positive outcomes using intestinal ultrasonography (US), with comparison with the established endpoint mucosal healing (MH).

METHODS

CD patients were consecutively recruited from September 2015 to August 2018 at a single tertiary hospital. All patients were evaluated at baseline and followed up at 6 months prospectively with a guideline-based treatment regimen. Achieving TH/MH or not was evaluated by US/colonoscopy at the first follow-up. Long-term outcomes including steroid-free clinical remission (CR), drug escalation, hospitalization, and surgery, were recorded after at least another 12 months.

RESULTS

We identified 77 patients with a median age of 30 years (range, 12-73 years). Twenty-five (32%) patients achieved TH, and 31 (40%) patients achieved MH. TH and MH were poorly correlated (Cohen's κ = 0.387; p < 0.05). Univariate analysis showed that both MH and TH were associated with better long-term outcomes. In multivariate analysis, TH was an independent predictor of steroid-free CR [odds ratio (OR), 52.6; p < 0.001], drug escalation (OR, 0.1; p = 0.002), and hospitalization (OR, 0.05; p = 0.005), while MH was an independent predictor of drug escalation (OR, 0.3; p = 0.05). Smoking habit was the only predictor of surgery (OR, 6.6; p = 0.02).

CONCLUSION

TH is an independent predictor of more favorable long-term outcomes than MH, suggesting that TH could become the potential treatment endpoint in CD.Plain language summary: Transmural healing predicts good prognosis in Crohn's disease The therapeutic endpoints of Crohn's disease keep evolving. The long-term clinical significance of achieving transmural healing is not fully discovered.Transmural healing is an independent predictor of more favorable long-term outcomes than mucosal healing.Transmural healing could become the potential treatment endpoint in Crohn's disease.

Ultrasonographic Evaluation of Intestinal Fibrosis and Inflammation in Crohn's Disease. The State of the Art

The evaluation of the degree of inflammation and fibrosis, intrinsic elements in intestinal wall damage of Crohn’s disease, is essential to individuate the extent of the lesions and the presence of strictures. This information will contribute to the choice of the appropriate therapeutic approach, the prediction of the response to therapy and the course of the disease. The accurate evaluation of the extent and severity of inflammation and/or fibrosis in Crohn’s disease currently requires histopathological analysis of the intestinal wall. However, in clinical practice and research, transmural assessment of the intestinal wall with cross sectional imaging is increasingly used for this purpose. The B-mode ultrasonograhic characteristics of the intestinal wall, the assessment of its vascularization by color Doppler and I.V. contrast agents, and the evaluation of the mechanical and elastic properties by sonoelastography, may provide useful and accurate information on the severity and extent of inflammation and intestinal fibrosis in Crohn’s disease. The purpose of this review is to provide an update on current sonographic methods to discriminate inflammation and fibrosis in Crohn’s disease.

Correlation between endoscopy and intestinal ultrasound for the evaluation of postoperative recurrence of Crohn's disease

OBJECTIVE

Intestinal ultrasound is considered to be a valid alternative for the evaluation of post-operative recurrence (POR) of Crohn's disease. The aim of this study is to assess the correlation between ultrasound and endoscopic findings.

METHODS

Patients with Crohn's disease were retrospectively recruited who had undergone ileocecal resection, and for whom a colonoscopy and intestinal ultrasound had been performed for the detection of POR. Recurrence was assessed using the Rutgeerts score (RS). The ultrasound findings analysed were bowel wall thickness (BWT), parietal hyperaemia using power Doppler, loss of layer pattern and mesenteric fat hypertrophy.

RESULTS

A total of 31 patients were included, of which 15 (48.4%) had no POR (RS<2b) and 16 (51.6%) had POR (RS≥2b). A statistically significant association was identified between BWT and the presence of endoscopic recurrence (a mean of 2.75mm vs. 5.68mm, P>0.001). There was also a statistically significant difference in hyperaemia between the 2groups (P=0.03). For wall thickness, an area under the ROC curve (AUC) of 92.9% was obtained, and with a cut-off point of 3.4mm, a sensitivity of 100% and specificity of 86.6%. When comparing with the most frequent biomarkers (fecal calprotectin and serum CRP), a higher AUC was obtained for wall thickness (72.3% and 72.3% vs. 92.9%).

CONCLUSIONS

In our experience, ultrasound has high diagnostic efficacy in the detection of POR and can be considered a valid non-invasive alternative to endoscopy.

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.

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.

Usefulness of intestinal ultrasound in inflammatory bowel disease

Imaging techniques play a fundamental role in the initial diagnosis and follow-up of inflammatory bowel disease. Intestinal ultrasound has high sensitivity and specificity in patients with suspected Crohn's disease and in the detection of inflammatory activity. This technique enables the early diagnosis of intra-abdominal complications such as stenosis, fistulas, and abscesses. It has also proven useful in monitoring the response to treatment and in detecting postsurgical recurrence. Technical improvements in ultrasound scanners, technological advances such as ultrasound contrast agents and elastography, and above all increased experience have increased the role of ultrasound in the evaluation of the gastrointestinal tract. The features that make ultrasound especially attractive include its wide availability, its noninvasiveness and lack of ionizing radiation, its low cost, and its good reproducibility, which is important because it is easy to repeat the study and the study is well tolerated during follow-up. This review summarizes the role of intestinal ultrasound in the detection and follow-up of inflammatory bowel disease.

Pathophysiology of Crohn's disease inflammation and recurrence

Chron’s Disease is a chronic inflammatory intestinal disease, first described at the beginning of the last century. The disease is characterized by the alternation of periods of flares and remissions influenced by a complex pathogenesis in which inflammation plays a key role. Crohn’s disease evolution is mediated by a complex alteration of the inflammatory response which is characterized by alterations of the innate immunity of the intestinal mucosa barrier together with a remodeling of the extracellular matrix through the expression of metalloproteins and increased adhesion molecules expression, such as MAcCAM-1. This reshaped microenvironment enhances leucocytes migration in the sites of inflammation, promoting a T_H1 response, through the production of cytokines such as IL-12 and TNF-α. IL-12 itself and IL-23 have been targeted for the medical treatment of CD. Giving the limited success of medical therapies, the treatment of the disease is invariably surgical. This review will highlight the role of inflammation in CD and describe the surgical approaches for the prevention of the almost inevitable recurrence.

Targeting the gut layers in Crohn's disease: mucosal or transmural healing?

INTRODUCTION

Although the landmark of Crohn's Disease (CD) is the transmural inflammation, mucosal healing (MH), which is assessed by colonoscopy, is currently the gold standard of CD management. Transmural healing (TH) is a new concept evaluated by cross-sectional imaging (CSI) techniques, such as bowel ultrasound (US), computed tomography enterography (CTE), and magnetic resonance enterography (MRE). Little is known about the clinical significance of persisting mural disease and the predictive value of complete TH.

AREAS COVERED

The authors reviewed the available literature on TH and its meaning as predictor of long-term outcomes in CD, to explore if TH may be a better target compared to MH in CD patients, in terms of disease outcome, such as medication changes, hospitalization, or surgery.

EXPERT OPINION

Some evidence suggests that achieving TH has a predictive value in CD management and correlates with better disease outcome than MH, although existing studies are few and with limitations. A definitive definition of TH is not yet established and the frequency or the preferred modality of TH evaluation remains unclear. Implementing TH in treat-to-target approach may enable stricter disease monitoring with noninvasive methods and finally change the disease course, preventing irreversible bowel damage.

Prevention of Postoperative Recurrence in CD: Tailoring Treatment to Patient Profile

Crohn's disease (CD) is an immune-mediated condition characterized by the transmural inflammation of the gut tissue, associated with progressive bowel damage often leading to surgical intervention. As operative resection of the damaged segment is not curative, a majority of patients undergoing intestinal resections for complicated CD present disease recurrence within 3 years after the intervention. Postoperative recurrence can be defined as endoscopic, clinical, radiological or surgical. Endoscopic recurrence rates within 1 year exceed 60% and the severity, according to the Rutgeerts' score, is associated with worse prognosis and can predict clinical recurrence (in up to 1/3 of the patients). Most importantly, about 50% of patients will undergo a reoperation after 10 years of their first intestinal resection. Therefore, the prevention of postoperative recurrence in CD remains a challenge in clinical practice and should be properly managed. We aim to summarize the most recent data on the definition, risk factors, assessment and treatment of postoperative CD recurrence.

Surgical Prevention of Anastomotic Recurrence by Excluding Mesentery in Crohn's Disease: The SuPREMe-CD Study - A Randomized Clinical Trial

OBJECTIVE

This trial aimed to provide randomized controlled data comparing Kono-S anastomosis and stapled ileocolic side-to-side anastomosis.

BACKGROUND

Recently, a new antimesenteric, functional, end-to-end, hand-sewn ileocolic anastomosis (Kono-S) has shown a significant reduction in endoscopic recurrence score and surgical recurrence rate in Crohn disease (CD).

METHODS

Randomized controlled trial (RCT) at a tertiary referral institution. Primary endpoint: endoscopic recurrence (ER) (Rutgeerts score ≥i2) after 6 months. Secondary endpoints: clinical recurrence (CR) after 12 and 24 months, ER after 18 months, and surgical recurrence (SR) after 24 months.

RESULTS

In all, 79 ileocolic CD patients were randomized in Kono group (36) and Conventional group (43). After 6 months, 22.2% in the Kono group and 62.8% in the Conventional group presented an ER [P < 0.001, odds ratio (OR) 5.91]. A severe postoperative ER (Rutgeerts score ≥i3) was found in 13.8% of Kono versus 34.8% of Conventional group patients (P = 0.03, OR 3.32). CR rate was 8% in the Kono group versus 18% in the Conventional group after 12 months (P = 0.2), and 18% versus 30.2% after 24 months (P = 0.04, OR 3.47). SR rate after 24 months was 0% in the Kono group versus 4.6% in the Conventional group (P = 0.3). Patients with Kono-S anastomosis presented a longer time until CR than patients with side-to-side anastomosis (hazard ratio 0.36, P = 0.037). On binary logistic regression analysis, the Kono-S anastomosis was the only variable significantly associated with a reduced risk of ER (OR 0.19, P < 0.001). There were no differences in postoperative outcomes.

CONCLUSIONS

This is the first RCT comparing Kono-S anastomosis and standard anastomosis in CD. The results demonstrate a significant reduction in postoperative endoscopic and clinical recurrence rate for patients who underwent Kono-S anastomosis, and no safety issues.ClinicalTrials.gov ID NCT02631967.

Postoperative Crohn's disease management

PURPOSE OF REVIEW

Despite multiple advances in the medical treatment of Crohn's disease, it is recognized that a significant proportion of patients will ultimately require surgical resection at some point during their disease course. This review focuses on the postoperative management of patients with Crohn's disease, with the goal of preventing endoscopic and clinical recurrence, and future surgery.

RECENT FINDINGS

Surgery is an integral part of the multidisciplinary approach to the management of patients with Crohn's disease. Recent literature and guidelines have focused on a standardized and evidence-based approach to the management of patients in the postoperative setting. This approach should utilize risk stratification at the time of surgery, initiation of appropriate therapy among high-risk patients, and objective evaluation in the postoperative period, including ileocolonoscopy at 6-12 months after a surgical resection.

SUMMARY

A standardized approach to the postoperative management of patients with Crohn's disease is critical. Identifying those patients at high-risk for endoscopic and clinical recurrence is essential, as these patients will likely require early medical therapy. While novel objective assessments are emerging, all patients should undergo ileocolonoscopy at 6-12 months and further decision making should be based on the presence of endoscopic recurrence.

Perioperative and Postoperative Management of Patients With Crohn's Disease and Ulcerative Colitis

Although the number of available therapies for the treatment of ulcerative colitis and Crohn's disease (CD) continues to expand, a significant portion of patients with inflammatory bowel disease will require surgical intervention. Surgery remains an integral part of the treatment algorithm for patients with ulcerative colitis and CD, and thus multidisciplinary approaches to the perioperative and postoperative management of patients with inflammatory bowel disease are critical to improving outcomes during these periods. New mechanisms of biologic therapies are emerging and new treatment strategies focused on earlier and potentially more aggressive use of immunosuppressive therapies are advocated in the current treatment era. In this review, we outline multidisciplinary strategies for the preoperative management of immunosuppressive therapies, including a discussion of the most recent evidence regarding the safety of biologic therapy in the preoperative period. We also discuss the postoperative medical management of patients undergoing intestinal resection for CD, with a particular focus on risk stratification and appropriate therapy selection in the immediate postoperative setting. Finally, we review potential postoperative complications after restorative proctocolectomy with ileal pouch-anal anastomosis and their management.

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.

Value of magnetic resonance enterography in diagnosis and treatment follow up in Crohn's disease in children

PURPOSE

Crohn's disease (CD) is a chronic inflammatory disease which can affect all parts of the gastrointestinal tract. Magnetic resonance enterography (MRE) enables detection of pathologic changes in the small intestine, which are not accessible by conventional endoscopy. The aim of the study was to assess the value of MRE in imaging of small bowel lesions, their location and extent, in CD patients and its correlation with clinical and endoscopic activity.

MATERIALS AND METHODS

MRE was performed in 108 children with CD, aged 5.5 to 18 years. The diagnosis was based on the Porto criteria. Location and clinical manifestation was evaluated according to the Paris classification. Clinical CD activity was assessed with PCDAI and endoscopic activity with SES-CD. In 36 children, control MRE was performed.

RESULTS

The most common endoscopic location of the disease was the colon (41.7%), terminal ileum and colon (24.1%). Inflammation as the main clinical manifestation was dominant (81.5%). In MRE, inflammatory changes were found in 40.8% of children, strictures in 11.1%. The EIA value (activity in MRE) increased along with PCDAI score and SES-CD. MRE performed during follow up, showed transmural healing in 16.7% of patients and improvement in 55.5%.

CONCLUSIONS

MRE is an efficient diagnostic tool in proper characterization of disease location in pediatric CD. As positive correlation of the results of MRE with the endoscopic and clinical activity has been found, taking into account good tolerance and non-invasiveness of the procedure it can be recommended to be used in reassessment.

Systematic Review: Patient Perceptions of Monitoring Tools in Inflammatory Bowel Disease

Background and Aims

Inflammatory bowel disease (IBD) is a lifelong disease requiring frequent assessment to guide treatment and prevent flares or progression. Multiple tools are available for clinicians to monitor disease activity; however, there are a paucity of data to inform which monitoring tools are most acceptable to patients. The review aims to describe the available evidence for patient preference, satisfaction, tolerance and/or acceptability of the available monitoring tools in adults with IBD.

Methods

Embase, Medline, Cochrane Central and Clinical Trials.gov were searched from January 1980 to April 2019 for all study types reporting on the perspectives of adults with confirmed IBD on monitoring tools, where two or more tools were compared. Outcome measures with summary and descriptive data were presented.

Results

In 10 studies evaluating 1846 participants, monitoring tools included venipuncture, stool collection, gastrointestinal ultrasound, computed tomography, magnetic resonance imaging, wireless capsule endoscopy, barium follow-through and endoscopy. Outcome domains were patient satisfaction, acceptability of monitoring tool and patient preference. Noninvasive investigations were preferable to endoscopy in nine studies. When assessed, gastrointestinal ultrasound was consistently associated with greater acceptability and satisfaction compared with endoscopy or other imaging modalities.

Conclusions

Adults with IBD preferred noninvasive investigations, in particular gastrointestinal ultrasound, as compared to endoscopy for monitoring disease activity. When assessing disease activity, patient perceptions should be considered in the selection of monitoring tools. Further research should address whether adpoting monitoring approaches considered more acceptable to patients results in greater satisfaction, adherence and ultimately more beneficial clinical outcomes.

Impact of intestinal ultrasound on the management of patients with inflammatory bowel disease: how to apply scientific evidence to clinical practice

Technological improvements and growing sonographers' expertise boost the role of intestinal ultrasound (IUS) in assessing patients with inflammatory bowel diseases (IBD). Non-invasiveness, low cost and good reproducibility make IUS attractive. Leveraging on the Authors' long-term field experience, this review focuses on the IUS role in IBD patients' clinical management. For detecting IBD, particularly Crohn's disease, the IUS parameters - above all the evidence of a thickened bowel wall (BWT) - show very good diagnostic accuracy similar to that of MRI or CT scan. The standard IUS parameters are not accurate enough to detect inflammatory activity, but intravenous contrast-enhanced US (CEUS) is highly accurate in ruling active inflammation out. However, its routinely use remains limited in clinical practice and its parameters need standardization. IUS is accurate in detecting IBD main complications: in particular, fistulae and abscesses. As to stenosis the recent introduction of IUS-based elastographic techniques allows to differentiate prevalently inflammatory from highly fibrotic strictures. IUS proves valid also for monitoring IBD patients. In particular, the evidence of transmural healing, defined as BWT normalization, has got an important prognostic meaning, as associated with better long-term clinical outcomes. Post-surgery CD recurrence can be suggested by early IUS assessment.

Lower adalimumab trough levels are associated with higher bowel wall thickness in Crohn's disease

BACKGROUND

In Crohn's disease, higher adalimumab trough levels and negative anti-adalimumab-antibodies associate with better clinical and endoscopic outcomes. Intestinal ultrasound has become a relevant non-invasive method to monitor treatment. However, data on the association between adalimumab levels and bowel wall thickness measured with ultrasound is limited.

OBJECTIVE

The purpose of this study was to examine the possible association between the sonographic transmural-thickness and adalimumab trough levels.

METHODS

This prospective observational cohort study was conducted at Sheba Medical Center in 2014-2018. Crohn's disease patients on adalimumab maintenance therapy with intestinal ultrasound performed within <30 days of trough level measurement were included. Associations between terminal ileum and colonic thickness, adalimumab levels and therapy retention were assessed.

RESULTS

Fifty events of ultrasound with concomitant adalimumab trough level measurements in 44 Crohn's disease patients were included. Patients with trough level <3 μg/ml had significantly higher bowel wall thickness, both for terminal ileum (p = 0.04) and colon (p = 0.02). Thirty-two patients continued adalimumab therapy over one year. The adalimumab retention rate was higher among those with terminal ileum thickness <4 mm (p = 0.03).

CONCLUSION

Lower adalimumab trough levels were associated with higher bowel wall thickness indicating poorer therapy outcome. Transmural thickness measurement with ultrasound may be a useful target for guiding biologic therapy in Crohn's disease.

Diagnostic accuracy of intestinal ultrasound and magnetic resonance enterography for the detection of endoscopy-based disease activity in ileocolonic Crohn's disease

BACKGROUND

Crohn's disease (CD) is characterised by chronic gastrointestinal inflammation with relapsing-remitting behaviour and often requires endoscopic and/or radiologic assessment.

OBJECTIVE

The objective of this study was to compare the diagnostic accuracy of intestinal ultrasound (IUS) and magnetic resonance enterography (MRE) for the assessment of disease activity in CD using a simple endoscopic score for CD as a reference standard.

PATIENTS AND METHODS

A prospective observational study was carried out in 71 consecutive adult patients with known CD, attending our tertiary inflammatory bowel disease clinic, between November 2014 and July 2016. Ileocolonoscopy, IUS and MRE were performed within 1 month prospectively. The simple endoscopic score-CD 0-2 was accepted as remission.

RESULTS

The sensitivity of IUS and MRE for detecting endoscopic activity was found similar with regard to bowel wall thickening and mesenteric fibrofatty proliferation (P>0.05). The overall accuracy for detecting mural lesions was similar between IUS and MRE. When mural lesions were analysed, the sensitivity of MRE in detecting the loss of wall stratification and stenosis was significantly higher than IUS (P<0.001 for both). IUS showed higher specificity for bowel wall thickening, loss of wall stratification and stenosis (P=0.009, P<0.001 and P<0.001, respectively). Sensitivity and accuracy of IUS were higher in detecting ascites in active disease (P=0.002).

DISCUSSION

Our results showed that IUS and MRE were equally accurate in detecting endoscopic activity. IUS may be the preferred technique for the evaluation of disease activity and for the follow-up of CD.

Prediction of treatment outcome and relapse in inflammatory bowel disease

Prediction of treatment outcome and clinical relapse in patients with inflammatory bowel disease (IBD), either ulcerative colitis (UC) or Crohn's disease (CD), is particularly important because therapeutics for IBD are not always effective and patients in remission could frequently relapse. Because undergoing endoscopy for the purpose is sometimes invasive and burdensome to patients, the performance of surrogate biomarkers has been investigated. Areas covered: We particularly featured the performance of patient symptoms, blood markers including C-reactive protein (CRP), fecal markers including fecal calprotectin (Fcal) and fecal immunochemical test (FIT) for prediction of endoscopic mucosal healing (MH) and prediction of relapse. Studies of other modalities and therapeutic drug monitoring (TDM) have also been explored. Expert opinion: Meticulous evaluation of patient symptoms could be predictive for MH in UC. CRP and Fcal may be accurate in prediction of MH of CD when MH is evaluated throughout the entire intestine including the small bowel. Repeated measurements of fecal markers including Fcal and FIT in patients with clinical remission would raise predictability of relapse. Prediction of treatment outcome by monitoring with blood markers including CRP, fecal markers including Fcal, and TDM has frequently been performed in recent clinical trials and shown to be effective.

Intravenous Contrast-Enhanced Ultrasound for Assessing and Grading Postoperative Recurrence of Crohn's Disease

PURPOSE

The aim was to investigate the contribution of contrast-enhanced ultrasound (CEUS) to improve the results of US in the evaluation of recurrence in postsurgical Crohn's disease (CD) and establish its role in the assessment of the severity.

METHODS

Anastomotic site was assessed in 108 postsurgical CD patients with B-mode, color Doppler and CEUS. Bowel wall thickness (WT), transmural complications or stenosis, color Doppler grade, and bowel wall contrast enhancement (BWCE)-using time-intensity curves-were correlated with endoscopic Rutgeerts score. A receiver operating characteristic (ROC) curve was built to establish the best cutoff to predict recurrence and the severity. A US scoring system was elaborated in order to determine the grade of recurrence.

RESULTS

Ileocolonoscopy detected recurrence in 90 (83.3%) subjects and severe recurrence in 62. WT ≥ 3 mm had an accuracy of 90.7% in the detection of endoscopic recurrence. The combination of parameters-WT ≥ 3 mm and BWCE (≥ 46%)-demonstrated similar accuracy (90.7%). A WT ≥ 5 mm showed the best specificity (100%) for the diagnosis of recurrence and a WT ≥ 6 mm the best specificity (95.7%) for the detection of severe recurrence. The combination of sonographic parameters-WT ≥ 6 mm or WT between 5 and 6 mm with BWCE ≥ 70%, or complications-obtained the best results grading the recurrence (sensitivity, specificity, and accuracy of 90.3%, 87%, and 88.9%, respectively).

CONCLUSIONS

US shows high sensitivity and specificity for the diagnosis of postsurgical recurrence. When combined with CEUS, it can improve the detection of severe recurrence.

Role of Abdominal US in Diagnosis of NEC

Current assessment for and diagnosis of necrotizing enterocolitis (NEC) remain inadequate. The introduction of interrogating bowel with ultrasound when NEC is suspected or when NEC has occurred presents greater opportunity to characterize the physical changes that have occurred in the bowel wall structures. The evaluation of bowel by ultrasound has been shown to have high specificity for bowel necrosis. There are current barriers in adoption of these techniques because they have not been integrated into routine diagnostic imaging and are not well incorporated in neonatal medicine.