ECCO-ESGAR Guideline for Diagnostic Assessment in IBD Part 1: Initial diagnosis, monitoring of known IBD, detection of complications

Ultrasound Elastography in the Assessment of the Intestinal Changes in Inflammatory Bowel Disease-Systematic Review

Inflammatory bowel disease (IBD) is a chronic condition affecting primarily the gastrointestinal tract and characterized by growing incidence worldwide. Complex diagnostic process of IBD as well as evaluation of disease activity and intestinal complications that are crucial for the therapeutic decisions, require repetitive, invasive, expensive, time-consuming and poorly tolerated tests. In contrast to endoscopy and computed tomography, ultrasound elastography (UE) is non-invasive, non-radiating and non-contrasting dependent tool which might be utilized in IBD patients for the assessment of the intestinal changes. Therefore, we performed the systematic review to evaluate the possible application of the ultrasound elastography for assessment of the intestinal changes in IBD. After the search of three databases: PubMed, World of Knowledge and Scopus, we identified 12 papers which were included in the final analysis. The majority of the studies were focused on the evaluation of the symptomatic ileal/ileocolonic strictures in Crohn's disease patients that required surgical resection. Only one study concerned ulcerative colitis. The authors evaluated different UE techniques: strain elastography (SE), acoustic radiation force impulse (ARFI) and shear wave elastography (SWE). Results were expressed with semi-quantitative color mapping and strain measurement. Histological scores of inflammation and fibrosis in Crohn's disease were used as a reference test in the majority of studies. Ultrasound elastography seems to be a promising novel imaging technique supporting evaluation of the intestinal strictures in Crohn's disease patients in respect to fibrosis detection as well as differentiation between fibrosis and inflammation. However, further research is needed to establish the position of ultrasound elastography in IBD management.

Patients Prioritize a Low-volume Bowel Preparation in Colitis-associated Colorectal Cancer Surveillance: A Discrete Choice Experiment

BACKGROUND

Patients with inflammatory bowel disease (IBD) undergo surveillance colonoscopies at fixed intervals to reduce the risk of colorectal cancer (CRC). Taking patients' preferences for determining surveillance strategies into account could improve adherence and patient satisfaction. This study aimed to determine patient preferences for CRC surveillance in IBD.

METHODS

We conducted a web-based, multicenter, discrete choice experiment among adult IBD patients with an indication for surveillance. Individuals were repeatedly asked to choose between 3 hypothetical surveillance scenarios. The choice tasks were based on bowel preparation (0.3-4 L), CRC risk reduction (8% to 1%-6%), and interval (1-10 years). Attribute importance scores, trade-offs, and willingness to participate were calculated using a multinomial logit model. Latent class analysis was used to identify subgroups with similar preferences.

RESULTS

In total, 310 of 386 sent out questionnaires were completed and included in the study. Bowel preparation was prioritized (attribute importance score 40.5%) over surveillance interval and CRC risk reduction (31.1% and 28.4%, respectively). Maximal CRC risk reduction, low-volume bowel preparation (0.3 L laxative with 2 L clear liquid) with 2-year surveillance was the most preferred combination. Three subgroups were identified: a "surveillance avoidant," "CRC risk avoidant," and "surveillance preferring" groups. Membership was correlated with age, educational level, perceived CRC risk, the burden of bowel preparation, and colonoscopies.

CONCLUSIONS

Inflammatory bowel disease patients consider bowel preparation as the most important element in acceptance of CRC surveillance. Heterogeneity in preferences was explained by 3 latent subgroups. These findings may help to develop an individualized endoscopic surveillance strategy in IBD patients.

The role of small-bowel endoscopy in inflammatory bowel disease: an updated review on the state-of-the-art in 2021

The impact of small-bowel (SB) capsule endoscopy and device-assisted enteroscopy on clinical practice, since their introduction 2 decades ago, has been remarkable. These disruptive technologies have transformed the investigation and management of SB pathology and now have a firmly established place in guidelines and clinical algorithms. Furthermore, recent years have witnessed innovations, driven by the demand of new goals in the management of inflammatory bowel disease (IBD), such as mucosal healing and evolving strategies based on tight monitoring and accelerated escalation of care. These developments in SB endoscopy have also been paralleled by refinement in dedicated radiological SB imaging technologies. This updated review highlights the current state of the art and more recent innovations with a focus on their role in IBD.

Characterization of Crohn's disease patients in Egypt: Risk factors for postoperative recurrence (A cohort study)

BACKGROUND

The aim of study to identify the characterizations of Crohn's disease in Egyptian patients and to determine its predictors for postoperative recurrence.

METHODS

We conducted a retrospective observational cohort study on 15 patients diagnosed as Crohn's disease with surgical interventions. Different characteristics of studied patients were analyzed to determine the risk factors for postoperative recurrence such as age at diagnosis, gender, smoking, main presenting symptom, Montreal classification, perianal disease, laboratory findings and protocol of management including surgical characteristics like age at operation, surgical indication, preoperative medication, surgical approach, and operative findings.

RESULTS

Nine of the studied patients (60%) suffered from clinical postoperative recurrence with mean duration of 23.5 ± 40.6 months. In comparison the demographic, clinical, operative, and medical treatment data between patients with postoperative recurrence of Crohn's disease and those without recurrence, age at diagnosis (mean age 42.9 years) and age at operation (mean 44.7 years) were found statistically significant in postoperative recurrence group (p-value = 0.001). According to Montreal classification of Crohn's disease, patients >40 years were significantly found in postoperative recurrence group, while patients between 17 and 40 years were significantly found in postoperative non-recurrence group (p-value=0.007) and ileal location of Crohn's disease was found significantly in postoperative recurrent group (p-value=0.044). Postoperative biological therapy significantly decreased the incidence of postoperative recurrence in the current study (p-value= 0.041).

CONCLUSIONS

Age at diagnosis, age at operation, ileal location of Crohn's disease can significantly predict postoperative recurrence. Also, postoperative biological therapy can significantly decrease the incidence of postoperative recurrence.

Limited long-term treatment persistence of first anti-TNF therapy in 538 patients with inflammatory bowel diseases: a 20-year real-world study

BACKGROUND

Anti-TNF antibodies were the first biologic treatment option for patients with inflammatory bowel diseases.

AIMS

To assess length of treatment persistence of first anti-TNF therapy and influencing factors used in the standard care of patients with inflammatory bowel diseases.

METHODS

Single-centre, retrospective study from a register including patients who received anti-TNF therapy in the last 20 years at the study centre. Kaplan-Meier analysis with log-rank test was used to describe treatment persistence. With multivariable Cox regression analysis, risk factors for treatment failure were investigated.

RESULTS

Five hundred thirty-eight patients (CD, Crohn's disease: 367, UC, ulcerative colitis: 147, inflammatory bowel disease unclassified: 24) with a median follow-up of 8.1 years were included. Median (95% confidence interval) treatment persistence in the total cohort was 2.3 years (28 [22, 38] months), and nearly half of patients withdrew from treatment within 2 years. Male patients were treated longer than females (male: 37 [25, 48] months, female: 23 [14, 33] months, P = 0.002). Treatment persistence was longer in CD compared to UC (CD: 39 [30, 50] months, UC: 13 [9, 19] months, P < 0.001), and patients with CD remained longer on adalimumab than on infliximab treatment (adalimumab: 67 [55, 95] months, infliximab: 19 [14, 31] months, P < 0.001). Treatment failure (52%) and side effects (25%) were the most common reasons for withdrawal from therapy; 14% withdrew due to remission. Female sex was identified as independent predictor for treatment failure in UC (hazard ratio [CI]: 1.73 [1.02-2.92], P = 0.04).

CONCLUSION

Long-term treatment persistence of first anti-TNF therapy was limited in patients with inflammatory bowel diseases, primarily due to treatment failure and side effects.

Multicentre randomised controlled trial on virtual chromoendoscopy in the detection of neoplasia during colitis surveillance high-definition colonoscopy (the VIRTUOSO trial)

BACKGROUND

Longstanding colonic IBD increases the risk of developing colorectal cancer. The utility of chromoendoscopy with standard-definition white light technology has been established. However, the use of high-definition virtual chromoendoscopy (HDV) in colitis surveillance remains undefined.

OBJECTIVE

To compare the performance of HDV (i-scan OE mode 2) with high-definition white light (HDWL) for detection of neoplasia in patients with IBD undergoing surveillance colonoscopy. Additionally, we assessed the utility of protocol-guided quadrantic non-targeted biopsies.

DESIGN

A multioperator randomised controlled trial was carried out in two centres in the UK. Total of 188 patients (101 men, mean age 54) with longstanding ulcerative or Crohn's colitis were randomised, prior to starting the surveillance colonoscopy, to using either HDV (n=94) or HDWL (n=94) on withdrawal. Targeted and quadrantic non-targeted biopsies were taken in both arms per-randomisation protocol. The primary outcome was the difference in neoplasia detection rate (NDR) between HDV and HDWL.

RESULTS

There was no significant difference between HDWL and HDV for neoplasia detection. The NDR was not significantly different for HDWL (24.2%) and HDV (14.9%) (p=0.14). All intraepithelial neoplasia (IEN) detected contained low-grade dysplasia only. A total of 6751 non-targeted biopsies detected one IEN only. The withdrawal time was similar in both arms of the study; median of 24 min (HDWL) versus 25.5 min (HDV).

CONCLUSION

HDV and HDWL did not differ significantly in the detection of neoplasia. Almost all neoplasia were detected on targeted biopsy or resection. Quadrantic non-targeted biopsies have negligible additional gain.

TRIAL REGISTRATION NUMBER

Clinical Trial.gov ID NCT02822352.

Monitoring established Crohn's disease with pan-intestinal video capsule endoscopy in Europe: clinician consultation using the nominal group technique

OBJECTIVE

Monitoring established Crohn's disease (CD) through a "treat-to-target" strategy aims to reduce and prevent long-term bowel damage and disability. Despite the availability of different monitoring techniques, there is a current lack of integrated evidence to guide optimal monitoring in terms of appropriate tools and timing. Pan-intestinal video capsule endoscopy (PCE) enables non-invasive and direct visualization of the entire intestinal tract with proven safety and efficacy. This study aims to generate insights on the value of PCE for monitoring established CD from the physician's perspective.

METHODS

The Nominal Group Technique (NGT) was used to create discussion around pre-defined research questions aimed at identifying target patient populations for PCE, benefits of PCE in terms of improving disease management, comparative benefits of PCE over standard of care, research priorities to ratify the use of PCE, and hurdles to PCE utilization. A NGT panel was held in Brussels, Belgium in October 2018 with 9 gastroenterology experts. Data were collected from multiple rankings of statements to the research questions and analyzed descriptively.

RESULTS

Consensus indicated that PCE is differentiated from other diagnostic tools, allowing for non-invasive and direct visualization of the luminal intestinal tract in one single procedure. Participants agreed that PCE is beneficial for mapping and grading established CD in all patients, enabling individual and tailored treatment decision-making. Time required to read PCE results was identified as the main utilization hurdle by participants. Well-designed studies are needed to confirm improved outcomes amongst patients with CD managed through a PCE-guided approach.

CONCLUSIONS

This study, using the NGT, generated expert opinion on the value of PCE for monitoring established CD in terms of target patient populations and benefits compared to other diagnostic modalities. Participants perceived PCE to facilitate a "treat-to-target" strategy for CD management. Further research is needed to support this value perception.

Bioelectrical impedance analysis-based nomogram construction for predicting secondary loss of response to infliximab in bio-naïve Crohn's disease patients

BACKGROUND

Infliximab is emerging as the first-line therapy for Crohn's disease (CD); however, the rate of secondary loss of response (SLR) can exceed 50%. This study aimed to construct a nomogram based on bioelectrical impedance analysis (BIA) indexes and laboratory markers to predict SLR to infliximab in biologically naïve CD patients.

METHODS

Data of 136 biologically naïve CD patients treated between September 2019 and March 2021 were retrospectively retrieved. BIA-based body composition parameters and laboratory markers were obtained before the infliximab therapy. Predictor selection was conducted using the least absolute shrinkage and selection operator (LASSO) and univariate logistic regression. The nomogram was developed using multivariable logistic regression, and internal validation was made by ten-fold cross-validation.

RESULTS

SLR occurred in 51% of the CD patients during 54 weeks. The nomogram predictors included hemoglobin, albumin, serum iron, and BIA scores. The nomogram showed significant discrimination (area under the curve [AUC], 0.920; 95% confidence interval, 0.873-0.967) and calibration (mean error = 0.012). Decision curve analysis (DCA) indicated that the nomogram provided net clinical benefit when the risk probability was between 2% and 83%. Internal validation assessment of the nomogram robustness found an AUC of 0.904 and an accuracy of 0.841.

CONCLUSIONS

This BIA-based body composition parameters- and laboratory markers-based novel nomogram could act as a predictive tool to evaluate SLR to infliximab therapy, crucial for optimizing treatment strategies and switching biologics in CD.

Role of capsule endoscopy in inflammatory bowel disease: Anything new?

Capsule endoscopy (CE) is a recently developed diagnostic method for diseases of the small bowel that is non-invasive, safe, and highly tolerable. Its role in patients with inflammatory bowel disease has been widely validated in suspected and established Crohn’s disease (CD) due to its ability to assess superficial lesions not detected by cross-sectional imaging and proximal lesions of the small bowel not evaluable by ileocolonoscopy. Because CE is a highly sensitive but less specific technique, differential diagnoses that can simulate CD must be considered, and its interpretation should be supported by other clinical and laboratory indicators. The use of validated scoring systems to characterize and estimate lesion severity (Lewis score, Capsule Endoscopy Crohn’s Disease Activity Index), as well as the standardization of the language used to define the lesions (Delphi Consensus), have reduced the interobserver variability in CE reading observed in clinical practice, allowing for the optimization of diagnoses and clinical management strategies. The appearance of the panenteric CE, the incorporation of artificial intelligence, magnetically-guided capsules, and tissue biopsies are elements that contribute to CE being a promising, unique diagnostic tool in digestive tract diseases.

JAK-STAT Pathway Regulation of Intestinal Permeability: Pathogenic Roles and Therapeutic Opportunities in Inflammatory Bowel Disease

The epithelial barrier forms the interface between luminal microbes and the host immune system and is the first site of exposure to many of the environmental factors that trigger disease activity in chronic inflammatory bowel disease (IBD). Disruption of the epithelial barrier, in the form of increased intestinal permeability, is a feature of IBD and other inflammatory diseases, including celiac disease and type 1 diabetes. Variants in genes that regulate or belong to the JAK-STAT signaling pathway are associated with IBD risk. Inhibitors of the JAK-STAT pathway are now effective therapeutic options in IBD. This review will discuss emerging evidence that JAK inhibitors can be used to improve defects in intestinal permeability and how this plays a key role in resolving intestinal inflammation.

A deep learning framework for autonomous detection and classification of Crohn's disease lesions in the small bowel and colon with capsule endoscopy

Background and study aims  Small bowel ulcerations are efficiently detected with deep learning techniques, whereas the ability to diagnose Crohn's disease (CD) in the colon with it is unknown. This study examined the ability of a deep learning framework to detect CD lesions with pan-enteric capsule endoscopy (CE) and classify lesions of different severity. Patients and methods  CEs from patients with suspected or known CD were included in the analysis. Two experienced gastroenterologists classified anonymized images into normal mucosa, non-ulcerated inflammation, aphthous ulceration, ulcer, or fissure/extensive ulceration. An automated framework incorporating multiple ResNet-50 architectures was trained. To improve its robustness and ability to characterize lesions, image processing methods focused on texture enhancement were employed. Results  A total of 7744 images from 38 patients with CD were collected (small bowel 4972, colon 2772) of which 2748 contained at least one ulceration (small bowel 1857, colon 891). With a patient-dependent split of images for training, validation, and testing, ulcerations were diagnosed with a sensitivity, specificity, and diagnostic accuracy of 95.7 % (CI 93.4-97.4), 99.8 % (CI 99.2-100), and 98.4 % (CI 97.6-99.0), respectively. The diagnostic accuracy was 98.5 % (CI 97.5-99.2) for the small bowel and 98.1 % (CI 96.3-99.2) for the colon. Ulcerations of different severities were classified with substantial agreement (κ = 0.72). Conclusions  Our proposed framework is in excellent agreement with the clinical standard, and diagnostic accuracies are equally high for the small bowel and colon. Deep learning approaches have a great potential to help clinicians detect, localize, and determine the severity of CD with pan-enteric CE.

Role of Intestinal Ultrasound in the Evaluation of Postsurgical Recurrence in Crohn’s Disease: Correlation with Endoscopic Findings

<b><i>Introduction:</i></b> Endoscopy remains the exam of choice in the evaluation of activity in Crohn’s disease (CD) after surgery (ACD-AS). However, intestinal ultrasound (IUS) may represent a noninvasive alternative. The objective of this study is to determine the diagnostic accuracy of this modality compared to endoscopy. <b><i>Material and Methods:</i></b> This is a cross-sectional study, comprising a period of 14 months, carried out in patients with established CD and ileocecal resection due to the disease. IUS (HI-VISION Avius®, Tokyo, Japan) was performed with linear probe B-mode/Doppler prior to ileocolonoscopy. IUS and ileocolonoscopy were performed on the same day by 2 specialists in Gastroenterology dedicated to ultrasound and inflammatory bowel disease, in a double-blind mode. Collected demographic and clinical data (Harvey-Bradshaw Index [HBI]; remission ≤4), serological/fecal inflammatory parameters (leukocytes [4–10 × 10⁹ cells/L], C-reactive protein [≤0.5 mg/dL], and fecal calprotectin [&#x3c;50 mg/kg]), endoscopy (Rutgeerts score: remission &#x3c;i2), and ultrasound (intestinal wall thickening [≤3 mm] and digestive wall vascularization using the semiquantitative score of Limberg [absent = 0, sparse = 1, moderate = 2, and marked = 3]). <b><i>Results:</i></b> Thirty-nine patients (female: 64.1%, mean age: 43.5 ± 15.3 years) were included. The median post-surgery follow-up was 9 years (IQR 3–12). The Montreal classification was as follows: L1, 61.5% (<i>n</i> = 24); L3, 38.5% (<i>n</i> = 15); B1 and B2, 28.2% (<i>n</i> = 11); and B3, 43.6% (<i>n</i> = 17). Most patients were in clinical remission (87.2%; <i>n</i> = 34), with a mean HBI of 2.1 ± 2.2. Twenty-two patients (56.4%) had normal inflammatory markers. IUS (intestinal wall thickening &#x3e;3 mm and/or Limberg score &#x3e;1) was abnormal in 61.5% (<i>n</i> = 24) of the cases. Endoscopic remission (Rutgeerts score &#x3c;i2) in 53.8% (<i>n</i> = 21) of the cases. Compared to endoscopy, IUS (area under the receiver operating characteristic curve [AUROC] = 0.75, <i>p</i> = 0.007) showed a diagnostic accuracy superior to that of inflammatory parameters (AUROC = 0.66, <i>p</i> = 0.083) and clinical parameters (AUROC = 0.64, <i>p</i> = 0.139). IUS showed a moderate concordance with endoscopy (κ = 0.5, <i>p</i> = 0.001), which was higher than that with inflammatory parameters (ĸ = 0.33, <i>p</i> = 0.041) or clinical parameters (ĸ = 0.29, <i>p</i> = 0.01). <b><i>Conclusions:</i></b> Ultrasound evaluation of the digestive wall is a noninvasive technique that shows a good diagnostic accuracy and a moderate concordance with endoscopy, being superior to clinical and serological/fecal inflammatory parameters.

Serum exosomal pregnancy zone protein as a promising biomarker in inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a kind of intestinal immune dysfunction disease, and its occurrence and prevalence are on the rise worldwide. As a chronic gastrointestinal disease, its pathogenesis is still unknown. Exosomes are vesicles in various body fluids that carry a variety of substances. They can mediate intercellular communication and long-distance transport of multiple media. In this study, we investigated the protein profile of serum exosomes from healthy people and IBD patients to explore a new serological biomarker for IBD.

METHODS

Initially, exosomes were extracted from serum samples, and the proteins within the exosomes were identified by label-free liquid chromatography/mass spectrometry (LC-MS/MS). Western blot and ELISA were used to assess the identified protein. To further analyze the target protein, an acute colitis mouse model was established, and exosomes in colonic tissue and serum were extracted to investigate the protein in them.

RESULTS

Firstly, serum exosomes were extracted from samples, and proteins in exosomes were identified by LC-MS/MS. Through statistical analysis, we identified 633 proteins. Among these proteins, pregnancy zone protein (PZP) showed a marked difference between patients with IBD and healthy people, in that its expression level was much higher in the IBD patients This exosomal protein was associated with immunosuppressive effects. Also, the level of PZP in colon tissue exosomes and serum exosomes of acute colitis mice was significantly higher than that of the control group.

CONCLUSIONS

Our findings indicated that serum exosome PZP was present at a high level in the IBD patients. Hence it might be a promising biomarker and enhance auxiliary diagnosis of IBD.

Prognostic value of ultrasound activity and parietal healing in patients with Crohn's disease

INTRODUCTION

the "treat to target" strategy for the management of patients with Crohn's disease (CD) requires simple, reliable and non-invasive tools for continuous monitoring of the disease. Intestinal ultrasound has been proposed as an emerging technique that could be very useful in this field.

MATERIAL AND METHODS

patients who had undergone an intestinal ultrasound in the clinical practice between February 2013 and October 2018 at our hospital were retrospectively included. The evolution of the patients during follow-up was assessed based on the presence of ultrasound activity and the therapeutic changes based on the results.

RESULTS

two hundred and seventy-seven CD patients were included and the median follow-up time was 24 months (range 5-73 months). Signs of ultrasound inflammatory activity were identified in 166 patients (60 %), and of them, treatment was escalated in 116 patients (70 %) based on the results of the ultrasound. Among patients with identified ultrasound activity, in 166 patients (60 %) the evolution was less favorable than in those without activity, with a shorter time until the next outbreak. Thus, the median disease-free survival (without outbreaks) after performing the ultrasound was 18 months when ultrasound activity was identified (although in most of the patients [70 %] the treatment had been escalated) vs 47 months in patients without ultrasound activity. However, these differences were not statistically significant (p < 0.0001). Among the 111 patients without ultrasound activity, those who achieved "parietal healing" (74 patients) had a better evolution with a 12 % subsequent outbreak vs 27 % during follow-up (p = 0.05). Thus, 15 % of patients with parietal healing had an outbreak vs 34 % of those who had not normalized the ultrasound findings after three years of follow-up.

CONCLUSION

intestinal ultrasound is a technique capable of detecting inflammatory activity in patients with Crohn's disease and the presence of ultrasound activity is a risk factor for a new outbreak of activity and/or clinical relapse. Likewise, the presence of "parietal or transmural healing" (PH) is associated with a better evolution of patients during follow-up. Thus, it could be a more precise objective to consider deep remission in CD, with intestinal ultrasound being a useful technique for this purpose.

Incidence comparison of adverse events in patients with inflammatory bowel disease receiving different biologic agents: retrospective long-term evaluation

Background/Aims

Current literature is lacking in studies comparing the incidence of adverse events (AEs) in patients with inflammatory bowel diseases (IBD) treated with adalimumab (ADA) or vedolizumab (VDZ) in a real-life scenario. Therefore, our primary aim was to compare the AEs occurring in patients taking ADA to those of patients taking VDZ.

Methods

In this single center study, data on AEs from IBD patients who underwent treatment with ADA and VDZ were retrospectively collected. AE rates per 100 person-years were calculated. A Cox regression model was used to estimate the hazard ratios of the AEs between the 2 drugs.

Results

A total of 16 ADA patients (17.2%) and 11 VDZ patients (7.6%) had AEs causing drug interruption during the study period (P=0.02). Most of the AEs were noninfectious extraintestinal events (50% in ADA and 54.5% in VDZ) while infections accounted for 31.2% of the AEs in patients treated with ADA and 27.3% in those treated with VDZ. The incidence rate of AEs causing withdrawal of therapy was 13.2 per 100 person-years for ADA and 5.3 per 100 person-years for VDZ, corresponding to a 76% lower risk in patients in VDZ. Considering the first year of treatment, we observed 34 subjects treated with ADA (36.5%) having at least 1 AEs and 57 (39.3%) among those taking VDZ (P=0.67).

Conclusions

VDZ has a lower incidence rate of AEs causing withdrawal of treatment compared to ADA but a similar risk of AEs not causing drug interruption. Real-life head-to-head studies are still necessary to further explore the safety profile of these drugs.

Immune checkpoint inhibitor treatment induces colitis with heavy infiltration of CD8 + T cells and an infiltration pattern that resembles ulcerative colitis

Colitis is a common, but poorly understood, adverse event of immune checkpoint inhibitors that are standard-of-care for an expanding range of cancer types. This explorative study aimed to describe the immune infiltrates in the colon from individuals developing checkpoint inhibitor colitis and compare them to well-known immunophenotypes of acute graft-versus-host disease, ulcerative colitis, and Crohn’s disease. Colon biopsies (n = 20 per group) of patients with checkpoint inhibitor colitis, acute graft-versus-host disease, ulcerative colitis and Crohn’s disease, all colitis treatment-naïve, and of individuals with a normal colon were analyzed using immunohistochemistry: CD8 for cytotoxic T cells, CD4 for T helper cells, and CD68 to identify cells of macrophage lineage. CD8 + T cell, CD4 + T cell, and CD68 + cell counts were performed. Cell infiltration was scored as scattered/patchy or band-like in the superficial and deep gut mucosa. Checkpoint inhibitor colitis was found to be heavily infiltrated by CD8 + T cells. Comparative analysis between groups showed that both CD8 + T cell counts (P < 0.01) and immune cell infiltration patterns in checkpoint inhibitor colitis were most similar to those observed in ulcerative colitis, with a deep band-like CD4 + T cell infiltration pattern and a superficial band-like CD68 + cell infiltration pattern in both. In conclusion, this is the first immunohistopathological study comparing infiltrate characteristics of checkpoint inhibitor colitis, acute graft-versus-host disease, ulcerative colitis, and Crohn’s disease. Checkpoint inhibitor colitis samples are heterogeneous, heavily infiltrated by CD8 + T cells, and show an immune cell infiltration pattern that is more similar to ulcerative colitis than to colonic acute graft-versus-host disease or colonic Crohn’s disease.

Endpoints for Perianal Crohn's Disease Trials: Past, Present and Future

BACKGROUND AND AIMS

Since the 1980s, many studies have evaluated the efficacy of therapies to improve the outcomes of patients with perianal Crohn's disease. We performed a systematic review to describe the evolution of endpoints in perianal fistulizing Crohn's disease. Efficacy outcomes, definitions and measurement tools were assessed.

METHODS

Electronic databases were searched up to November 1, 2020. All published randomized placebo-controlled trials enrolling patients with perianal fistula and Crohn's disease were eligible for inclusion. Ongoing randomized clinical trials were also described.

RESULTS

Nineteen randomized controlled trials were included. Clinical efficacy endpoints were reported in all trials. Clinical response was the most frequent primary endpoint [6/19 studies, 31.6%], followed by clinical remission in four studies [21%]. Clinical response was defined as closure of at least 50% of fistulas, while remission was defined as closure of all fistulas. A combined clinical and radiological primary endpoint was used to assess fistula healing in four studies [21%]. The Perianal Disease Activity Index was a primary endpoint in only one study [5.5%]. In addition, eight ongoing controlled trials were identified. Combined clinical and radiological remission was the most frequent primary endpoint in these studies [4/8, 50%].

CONCLUSION

In this systematic review, significant changes in outcomes used in randomized clinical trials of perianal Crohn's disease were observed. Radiological endpoints are increasingly used in perianal fistulizing Crohn's disease trials.

JINLING (Judicious INdex of Luminal INflammation Grade) score, an effective indicator to assess inflammation severity in Crohn's disease

BACKGROUND

With the increasing demand for individualized treatment in Crohn's disease, a score for accurate evaluation of inflammation grade will be of great significance. We have developed the JINLING score to assess inflammation severity for Crohn's disease, which incorporates an endoscopic score (SES-CD) and a 2-item patient-reported outcome (PRO2). The aim of this study was to examine the performance of JINLING score in evaluating inflammation grade and the correlation with the clinical outcomes.

METHODS

The correlation between JINLING score and Global Histologic Disease Activity Score (GHAS), fecal calprotectin (FCP), and C-reactive protein (CRP) level was performed in an exploration phase with a retrospective data set. The data on clinical outcomes including medication effects, Crohn's disease-related surgery and biochemical results were collected from a single-center prospective validation cohort.

RESULTS

JINLING score correlated significantly with FCP, CRP, and hemoglobin in the exploration cohort (all P < 0.05). The receiver operating characteristic (ROC) curves based on a threshold Crohn's disease activity index value of 150, GHAS of 4, and FCP of 60 μg/g to identify disease activity, all showed a higher area under the curve with JINLING score than SES-CD or PRO2 alone. In the validation cohort, patients with high inflammation grade (JINLING ≥4) had higher GHAS, CRP, and FCP than low inflammation grade patients. High JINLING score was associated with an increased risk of treatment failure (hazard ratio 2.93; 95% confidence interval 1.13-7.61, P = 0.021).

CONCLUSION

This newly developed index served well for quantifying inflammation grade and predicting clinical outcomes. JINLING score has the potential to facilitate clinical decision-making and personalized therapy for Crohn's disease patients.

Crohn's Disease Only Visible on Small Bowel Capsule Endoscopy: A New Entity

BACKGROUND AND AIMS

In rare cases, the diagnosis of Crohn's disease (CD) can only be achieved using small bowel capsule endoscopy (SBCE). We investigate the characteristics of patients with CD only visible on SBCE and assess their disease course.

METHODS

Data of all adult patients with confirmed CD diagnosis based on SBCE with normal endoscopic and cross-sectional imaging findings were retrospectively collected in three tertiary-level hospitals from January 2014 to March 2020.

RESULTS

Thirteen patients were included. Ten patients were females, and the mean age at diagnosis was 36 years. Ileum was mostly involved (85%), while duodenum and jejunum were affected in 23% and 38% of the cases, respectively. Nine patients had one segment involved, while four subjects had two or three segments affected. All patients had inflammatory behavior. First treatment consisted of steroids in all cases, and six patients were later treated with immunosuppressant or biologics. After a mean follow-up of 27.5 months, no change in disease behavior, hospitalization, or CD-related surgery was observed.

CONCLUSIONS

CD only visible at SBCE is a rare condition with a more favorable disease course compared to general CD with a lower rate of complicated behavior, hospitalization, and surgery, despite a similar use of immunosuppressant or biologics.

Assessing adherence to infusion-based biologic therapies in patients with inflammatory bowel disease

BACKGROUND

The intravenous biologics infliximab and vedolizumab are effective long-term therapies for inflammatory bowel disease (IBD). Though highly effective, suboptimal adherence may result in loss of response and adverse sequelae. The extent and outcomes of suboptimal adherence with intravenous biologics, including in IBD, requires further evaluation.

OBJECTIVES

To ascertain adherence to infliximab and vedolizumab infusions, and determine factors associated with poorer adherence within an IBD cohort.

METHODS

A retrospective single-centre cohort study of IBD patients, assessing adherence to infliximab and vedolizumab over 2 years (July 1, 2017 to June 30, 2019) was conducted. Medical and pharmacy dispensing records were used to determine date of infusion. Adherence was assessed using the continuous, multiple interval measure of medication gaps (CMG). Objectively measured disease remission was achieved if one or more of endoscopic remission, faecal calprotectin <100 μg/mL and/or CRP <5 mg/mL occurred within 3 months of end of follow-up. Bivariate analysis and multiple linear regression elucidated factors associated with poorer adherence.

RESULTS

Of 193 IBD patients, 132 (68.4%) had Crohn's disease. One hundred and thirty six (70.5%) patients received infliximab and 57 (29.5%) received vedolizumab with a median 13 [IQR 11-14] doses administered per patient over 2 years. Adherence according to CMG was similar between infliximab and vedolizumab groups (median 1.5% vs 1.2%, p = 0.31). In multiple linear regression analysis male sex, shorter IBD duration and clinic non-attendances were each associated with poorer adherence (Beta 4.69, 3.90, 3.56 respectively, p < 0.05) and objective disease remission was inversely associated with poorer adherence (Beta -3.27, p < 0.05).

CONCLUSION

There was a wide range of adherence to biologic infusions in this IBD cohort with poorer adherence associated with patient related factors. Conversely, objectively measured remission was strongly associated with adherence. This emphasises the need for targeted interventions to improve adherence and monitoring, and mitigate treatment delays.

Femoral Vein Wall Thickness Measurement May Be a Distinctive Diagnostic Tool to Differentiate Behçet's Disease with Intestinal Involvement and Crohn's Disease

BACKGROUNDS

Behçet's disease (BD) and Crohn's disease (CD) cannot be easily differentiated in young adults presenting with nonspecific gastrointestinal (GI) manifestations due to similar extraintestinal manifestations. We recently showed that increased common femoral vein (CFV) thickness is a distinctive feature of BD, rarely present in other inflammatory or vascular diseases with a specificity higher than 80% for the cutoff value of ≥ 0.5 mm. We suggest that CFV thickness measurement with ultrasonography (US) can be a diagnostic tool for BD.

AIMS

To assess the diagnostic performance of CFV thickness measurement in the differential diagnosis of BD and CD.

METHODS

Patients with BD (n = 69), CD (n = 38), and healthy controls (HC) (n = 38) were included in the study. Bilateral CFV thickness was measured with Doppler US.

RESULTS

Both right and left CFV thicknesses were significantly higher in BD compared to HC and CD (for right: 0.76 mm vs 0.33 mm, for left: 0.78 mm vs 0.35 mm, p < 0.001 for both). CFV thicknesses in CD were similar to HC (p > 0.05 for both). CFV thickness was also similar between BD patients with and without GI involvement (p = 0.367). The diagnostic cutoff values of ≥ 0.5 mm for CFV thickness performed well against to both CD and HCs for discrimination of BD. The sensitivity and specificity rates were > 85% for both HC and CD. Positive and negative predictive values in our tertiary clinical setting were > 90%.

CONCLUSION

We found significantly lower CFV thickness in CD compared to BD. Our results suggest that CFV wall thickness measurement is a distinctive diagnostic tool for the differentiation of BD and CD and can be helpful in daily practice for the differentiation of two diseases.

Risk Factors of Urothelial Cancer in Inflammatory Bowel Disease

Extraintestinal cancers are important complications in patients with inflammatory bowel disease (IBD). A limited number of publications are available regarding the association between IBD and urothelial cancer. The primary outcome of our study was the comparison of the prevalence of urothelial cancer in patients with IBD with respect to the prevalence in the general population. Secondary outcomes were the assessment of risk factors for the onset of urothelial cancer in IBD. In a retrospective study we examined the medical records of all patients with a confirmed diagnosis of IBD followed in our clinic between 1978 and 2021. For each of the patients with identified urothelial cancer, more than ten patients without cancer were analyzed. Furthermore, 5739 patients with IBD were analyzed and 24 patients diagnosed with urothelial cancer were identified. The incidence of urothelial cancer, compared with the incidence in the general population, was not significantly different (0.42% vs. 0.42%; p = 0.98). Twenty-three cases were then compared (1 case was discarded due to lack of follow-up data) against 250 controls. During the multivariate analysis, smoking (odds ratio, OR = 8.15; 95% confidence interval, CI = 1.76-37.63; p = 0.007) and male sex (OR = 4.04; 95% CI = 1.29-12.66; p = 0.016) were found as risk factors. In conclusion, patients with IBD have a similar risk of developing urothelial cancer compared to the general population, but males with a history of smoking are at increased risk.

A propensity score-weighted comparison between adalimumab originator and its biosimilars, ABP501 and SB5, in inflammatory bowel disease: a multicenter Italian study

BACKGROUND

Adalimumab is an effective and safe biological drug for the treatment of inflammatory bowel disease (IBD). Nowadays, several biosimilar agents are available, but data regarding their efficacy and safety in patients with IBD are still lacking. We aimed to compare the effectiveness and tolerability between adalimumab originator, ABP501 and SB5 biosimilars in patients with IBD in the short term (after induction and after 6 months of treatment) through a propensity score-weighted multicenter cohort study.

METHODS

We included 156 patients with IBD, 69 patients with ulcerative colitis and 87 patients with Crohn's disease (CD) receiving ABP501 or SB5 biosimilars from January 2019 to April 2020 for moderate-to-severe disease. For comparison, a group of age- and sex-matched patients treated with adalimumab originator was used. We collected clinical and biochemical data after induction and at 6 months of treatment. Endoscopic data were recorded only at baseline.

RESULTS

Overall, clinical benefit was achieved by 86.4% and 85.3% after induction and at 6 months, respectively, without a statistically significant difference between the three treatment groups (p = 0.68 and p = 0.46). However, after induction, we found significant differences between the two types of the disease (ulcerative colitis or CD, p = 0.004), with a greater clinical benefit achieved by patients with CD. Also, the therapeutic optimization rate between the three drugs was not statistically significant different (p = 0.30). All treatments showed a good safety profile, with only 10 patients who needed to stop therapy because of adverse events.

CONCLUSION

Adalimumab biosimilars seem to be as effective and safe as the originator in patients with IBD. Surely, they represent a great opportunity to reduce the costs of biological therapies, however larger and longer real-life studies are necessary.

[Position paper on endoscopic reporting in IBD]

The complete and reliable documentation of endoscopic findings make up the crucial foundation for the treatment of patients with inflammatory bowel diseases such as Crohn´s disease and ulcerative colitis. These findings are, on the one hand, a prerequisite for therapeutic decisions and, on the other hand, important as a tool for assessing the response to ongoing treatments. Endoscopic reports should, therefore, be recorded according to standardized criteria to ensure that the findings of different endoscopists can be adequately compared and that changes in the course of the disease can be traced back. In consideration of these necessities, fifteen members of the Imaging Working Group of the German Kompetenznetz Darmerkrankungen have created a position paper proposing a structure and specifications for the documentation of endoscopic exams. In addition to the formal report structure, the recommendations address a large number of attributes of acute and chronic inflammatory alterations as well as endoscopically detectable complications, which are explained in detail and illustrated using exemplary images. In addition, more frequently used endoscopic activity indices are presented and their use in everyday clinical practice is discussed.

Antitumor Necrosis Factor Agents to Treat Endoscopic Postoperative Recurrence of Crohn's Disease: A Nationwide Study With Propensity-Matched Score Analysis

Patients with Crohn's disease experiencing endoscopic postoperative recurrence (POR) may benefit from antitumor necrosis factor (TNF) agents but scarce data on this are available. Our aim was to assess the efficacy of anti-TNF in improving mucosal lesions in patients with endoscopic POR.

Bowel ultrasound enhances predictive value based on clinical indicators: a scoring system for moderate-to-severe endoscopic activities in patients with ulcerative colitis

BACKGROUND AND AIM

The aim was to assess non-invasive factors among clinical features, laboratory, and bowel ultrasound (BUS) characteristics and to develop a scoring system to predict endoscopic activities for ulcerative colitis (UC) patients.

METHODS

We performed a retrospective study collecting UC patients between January 2015 to September 2020. Logistic regression was performed to predict moderate-to-severe endoscopic activities, defined as endoscopic Mayo score ⩾2. Model performance was described with discrimination and calibration ability and validated by internal and external methods.

RESULTS

A total of 103 and 29 patients were enrolled in the modeling and validation groups, respectively. Stool frequency ⩾5 times/day, hematochezia, erythrocyte sedimentation rate (ESR), and colonic wall flow in BUS were included into two predictive models for endoscopic activities, both with good discrimination ability [Area under curve (AUC) 0.879 and 0.882, p < 0.001] and a sensitivity of 76.7% and specificity of 92.3%, which showed an adequate calibration ability by using the Hosmer-Lemeshow test (p = 0.14 and 0.07). The external validation displayed consistent results with the above mentioned. Nomograms were also established for these models.

CONCLUSION

We developed predictive models for endoscopic disease activities by using noninvasive factors based on stool frequency, hematochezia, ESR, and colonic wall blood flow in BUS. These models performed well in the internal and external validation.

Feasibility of Intestinal MR Elastography in Inflammatory Bowel Disease

BACKGROUND

While MR enterography allows detection of inflammatory bowel disease (IBD), the findings continue to be of limited use in guiding treatment-medication vs. surgery.

PURPOSE

To test the feasibility of MR elastography of the gut in healthy volunteers and IBD patients.

STUDY TYPE

Prospective pilot.

POPULATION

Forty subjects (healthy volunteers: n = 20, 37 ± 14 years, 10 women; IBD patients: n = 20 (ulcerative colitis n = 9, Crohn's disease n = 11), 41 ± 15 years, 11 women).

FIELD STRENGTH/SEQUENCE

Multifrequency MR elastography using a single-shot spin-echo echo planar imaging sequence at 1.5 T with drive frequencies of 40, 50, 60, and 70 Hz.

ASSESSMENT

Maps of shear-wave speed (SWS, in m/s) and loss angle (φ, in rad), representing stiffness and solid-fluid behavior, respectively, were generated using tomoelastography data processing. Histopathological analysis of surgical specimens was used as reference standard in patients.

STATISTICAL TESTS

Unpaired t-test, one-way analysis of variance followed by Tukey post hoc analysis, Pearson's correlation coefficient and area under the receiver operating characteristic curve (AUC) with 95%-confidence interval (CI). Significance level of 5%.

RESULTS

MR elastography was feasible in all 40 subjects (100% technical success rate). SWS and φ were significantly increased in IBD by 21% and 20% (IBD: 1.45 ± 0.14 m/s and 0.78 ± 0.12 rad; healthy volunteers: 1.20 ± 0.14 m/s and 0.65 ± 0.06 rad), whereas no significant differences were found between ulcerative colitis and Crohn's disease (P = 0.74 and 0.90, respectively). In a preliminary assessment, a high diagnostic accuracy in detecting IBD was suggested by an AUC of 0.90 (CI: 0.81-0.96) for SWS and 0.84 (CI: 0.71-0.95) for φ.

DATA CONCLUSION

In this pilot study, our results demonstrated the feasibility of MR elastography of the gut and showed an excellent diagnostic performance in predicting IBD.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 1.

Treatment outcomes of endoscopic submucosal dissection and surgery for colorectal neoplasms in patients with ulcerative colitis

Objectives

This study aimed to clarify the validity and long‐term outcomes of colorectal endoscopic submucosal dissection (ESD) of visible lesions (≥20 mm) in patients with ulcerative colitis (UC) and investigate the incidence of undetected lesions in surgical specimens.

Methods

This single‐center retrospective study included 11 lesions from nine patients with UC who underwent ESD and 19 lesions from nine patients with UC who underwent colectomy between March 2001 and January 2019. We evaluated the endoscopic findings of scarring, atrophy, and loss of haustra in the ESD group, and we determined the lesion visibility in the colectomy group. We investigated the clinicopathological features of all lesions and examined the follow‐up evaluations in the ESD group.

Results

The en bloc and curative resection rates of ESDs were 91% and 82%, respectively. Endoscopic findings of scarring, atrophic colitis, and loss of haustra were observed in two (18%), seven (64%), and one (9%) lesions, respectively. The two lesions with scarring showed severe submucosal fibrosis. Mortality and recurrence were not observed during the median follow‐up of 25 months. Metachronous lesions ≥20 mm were detected in two patients, which were successfully treated with ESDs. In the colectomy specimens, 21% of the lesions were undetected, 67% had multiple neoplasms, and 33% had multiple invasive cancers.

Conclusions

ESD is feasible and valid for large visible lesions in patients with UC; however, for lesions with endoscopic findings of scarring, technical difficulties in endoscopic resection must be considered. In addition, intensive surveillance colonoscopy is necessary to detect undetected lesions.

Summarise the estabished knowledge on this subject

The number of patients with ulcerative colitis (UC) has increased.

Clinical guidelines recommend that endoscopic resection for endoscopically visible dysplasia rather than colectomy in patients with UC.

Although some studies on the treatment outcomes of endoscopic submucosal dissection (ESD) for patients with UC have been conducted, the sample size was small and almost all reported lesions were relatively small (i.e., <20 mm); thus, the available data are limited.

What are the significance and/or new findins of this study?

Good outcomes of ESD for visible lesions (>20 mm) in patients with ulcerative colitis were demonstrated.

Technical difficulties are highly possible in lesions with endoscopic findings of scarring.

The prevalence of undetected lesions (approximately 20%) was the same between high (2‐3) and low (0‐1) Mayo endoscopic subscore groups based on the surgical specimens.

ECCO Topical Review Optimising Reporting in Surgery, Endoscopy, and Histopathology

BACKGROUND AND AIMS

Diagnosis and management of inflammatory bowel diseases [IBD] requires a lifelong multidisciplinary approach. The quality of medical reporting is crucial in this context. The present topical review addresses the need for optimised reporting in endoscopy, surgery, and histopathology.

METHODS

A consensus expert panel consisting of gastroenterologists, surgeons, and pathologists, convened by the European Crohn's and Colitis Organisation, performed a systematic literature review. The following topics were covered: in endoscopy: [i] general IBD endoscopy; [ii] disease activity and surveillance; [iii] endoscopy treatment in IBD; in surgery: [iv] medical history with surgical relevance, surgical indication, and strategy; [v] operative approach; [vi] intraoperative disease description; [vii] operative steps; in pathology: [viii] macroscopic assessment and interpretation of resection specimens; [ix] IBD histology, including biopsies, surgical resections, and neoplasia; [x] IBD histology conclusion and report. Statements were developed using a Delphi methodology incorporating two consecutive rounds. Current practice positions were set when ≥ 80% of participants agreed on a recommendation.

RESULTS

Thirty practice positions established a standard terminology for optimal reporting in endoscopy, surgery, and histopathology. Assessment of disease activity, surveillance recommendations, advice to surgeons for operative indication and strategies, including margins and extent of resection, and diagnostic criteria of IBD, as well as guidance for the interpretation of dysplasia and cancer, were handled. A standardised report including a core set of items to include in each specialty report, was defined.

CONCLUSIONS

Interdisciplinary high-quality care requires thorough and standardised reporting across specialties. This topical review offers an actionable framework and practice recommendations to optimise reporting in endoscopy, surgery, and histopathology.

Ability of Pelvic Magnetic Resonance Imaging to Predict Clinical Course of Perianal Fistula in Paediatric Crohn's Disease Patients

BACKGROUND AND AIMS

Evidence is limited regarding clinical course and magnetic resonance imaging [MRI] features of perianal fistula [PAF] in Korean children with Crohn's disease [CD]. We investigated MRI features of PAF and associations with long-term outcomes.

METHODS

We retrospectively analysed 243 patients with pelvic MRI for diagnosis of CD. Incidence of clinically evident PAF at diagnosis was determined, as were the proportions of patients with clinical failure [failure to achieve fistula healing within 1 year] and recurrence [new/recurrent PAF after fistula healing within 1 year]. Associations between outcomes and MRI features, specified in modified Van Assche index and MAGNIFI-CD, were evaluated. Associations between later development of clinically evident PAF and subclinical PAF detected on MRI at diagnosis were evaluated.

RESULTS

Among 243 included patients, 108 [44.4%] and 76 [31.3%] had clinically evident and subclinical PAF at diagnosis, respectively; 66.4% of the patients with clinically evident PAF achieved fistula healing within 1 year, and 32.7% of those patients developed recurrence. Fistula length and dominant features of the tracts were associated with clinical failure, and fistula length was associated with recurrence. Clinically evident PAF developed in 17.0% of the patients without clinically evident PAF at diagnosis. We did not find statistically significant association between subclinical PAF and later development of clinically evident PAF [adjusted hazard ratio, 2.438; p = 0.15].

CONCLUSIONS

A considerable proportion of Korean paediatric CD patients had clinically evident and subclinical PAF. Fistula length and dominant feature of the tract on MRI are useful predictors of outcomes.

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.

Qualitative sonographic assessment of transmural ileal inflammation in Crohn's disease: a comparison with MRI activity score

BACKGROUND

Intestinal ultrasound (IUS) is an accurate tool for monitoring Crohn's disease. To date, there is no clinically used validated quantitative ultrasonographic score for assessing disease activity. For magnetic resonance enterography (MRE), the magnetic resonance index of activity (MaRIA) is most used. The goal of this study was to devise a new quantitative IUS score for assessing Crohn's disease inflammation, by using a partial MaRIA score as a reference.

METHODS

This was a retrospective cohort study. The study cohort included patients with Crohn's disease followed between January 2016 and December 2018. Inclusion criteria were age >18 and <3 months between MRE and IUS. Linear/logistic regression was performed for the correlation of ultrasonographic parameters with MaRIA score. Ultrasonograpic features included: bowel wall thickness, disrupted bowel wall stratification, mesenteric fat proliferation, presence of lymph nodes, hypervascularity present on color Doppler flow, and the presence of complications (strictures, inflammatory mass, and fistula).

RESULTS

Forty-two patients were included. A stepwise multiple regression model was constructed to predict MaRIA score using ultrasound features. Two variables were found to be independently significant: terminal ileum (TI) thickness (r = 0.68, P = 0.001) and mesenteric fat proliferation (r = 0.45, P = 0.019). A model was constructed as follows: MaRIA = 7 + 2.5 * TI US thickness (mm) + 7 * US fat proliferation (0 = no, 1 = yes). This model has an R2 of 0.51 for explaining the variability in the results.

CONCLUSIONS

IUS measurements are significantly correlated with MaRIA score in the terminal ileum and a simple computational model can be constructed.

Approach to the Management of Recently Diagnosed Inflammatory Bowel Disease Patients: A User's Guide for Adult and Pediatric Gastroenterologists

Inflammatory bowel diseases (IBDs), including Crohn's disease and ulcerative colitis, are chronic, progressive, immune-mediated diseases of adults and children that have no cure. IBD can cause significant morbidity and lead to complications such as strictures, fistulas, infections, and cancer. In children, IBD can also result in growth impairment and pubertal delays. IBD is highly heterogenous, with severity ranging from mild to severe and symptoms ranging from mild to debilitating. Delay in IBD diagnosis, especially in Crohn's disease, is common and associated with adverse outcomes. Early diagnosis and prompt institution of treatment are the cornerstones for improving outcomes and maximizing health. Early diagnosis requires a low threshold of suspicion and red flags to guide early specialist referral at the primary provider level. Although the armamentarium of IBD medications is growing, many patients will not respond to treatment, and the selection of first-line therapy is critical. Risk stratification of disease severity, based on clinical, demographic, and serologic markers, can help guide selection of first-line therapy. Clinical decision support tools, genomics, and other biomarkers of response to therapy and risk of adverse events are the future of personalized medicine. After starting appropriate therapy, it is important to confirm remission using objective end points (treat to target) with continued control of inflammation with adjustment of therapy using surrogate biomarkers (tight control). Lastly, IBD therapy extends far beyond medications, and other aspects of the overall health and wellbeing of the patient are critical. These include preventive health, nutrition, and psychobehavioral support addressing patients' concerns around complementary therapy and medication adherence, prevention of disability, and ensuring open communication.

Silent Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is frequently associated with a variety of problematic symptoms, including abdominal pain and bowel habit changes, which are associated with poor patient quality of life and significant healthcare expenditure. Interestingly, silent IBD, a condition where patients demonstrate reduced perception and/or reporting of symptoms in the setting of active inflammation, may be as clinically consequential. This condition has been associated with serious complications leading to more costly interventions. It is by its nature an under-recognized phenomenon that affects substantial portions of patients with either Crohn's disease or ulcerative colitis. At the present time, although there are a variety of theories relating to the underlying causes and contributors, little is known about why this phenomenon occurs. As a result, there is a lack of cost-effective, reliable diagnostic methods to identify and manage "at-risk" patients. However, it is significantly likely that further study and an improved understanding of this condition will lead to improved approaches for the diagnosis and treatment of patients with silent IBD as well as other gastrointestinal disorders associated with alterations in symptomatic perception. In this article, we critically review studies that have investigated silent IBD. Specifically, we discuss the following: (1) the methods for defining silent IBD, (2) the known epidemiology of silent IBD, (3) potential causes of and contributors to this clinical entity, (4) current diagnostic modalities available to identify it, and (5) gaps in our understanding as well as potential novel diagnostic and therapeutic applications that could be developed with further study of this condition.

IBD goes home: from telemedicine to self-administered advanced therapies

Introduction: Major challenges have been posed by the coronavirus disease 2019 pandemic in the routine management of patients with inflammatory bowel disease (IBD). The need for constant monitoring of diseases activity and prompt adjustment of therapy have been balanced with the risk of contagion related to face-to-face consultations. Therefore, digital health initiatives have been pursued for safety reasons as vicarious instruments to avoid overcrowding of the IBD clinics. However, concerns and skepticism about the feasibility of digital health and telemedicine modalities limited their uptake in clinical practice in the pre-pandemic period.Areas covered: We conducted a literature overview on the current state of the art and the potential future benefits deriving from the integration of telemedicine systems, home-based laboratory tests, and self-administered drugs into IBD daily practice.Expert opinion: Digital health and telemedicine approaches at distance have been experimented as effective tools to avoid overcrowding of clinics and reduce risk from SARS-CoV2 exposure. Home-based point of care testing, such as fecal calprotectin and dried blood samples, might represent an effective method of remote monitoring of patients particularly when in-person visits are precluded. High expectations are placed on the use of self-administered advanced therapies, such as new subcutaneous formulation of biologics.

A Novel Radiomics Nomogram for the Prediction of Secondary Loss of Response to Infliximab in Crohn's Disease

Purpose

The prediction of the loss of response (LOR) to infliximab (IFX) is crucial for optimizing treatment strategies and shifting biologics. However, a secondary LOR is difficult to predict by endoscopy due to the intestinal stricture, perforation, and fistulas. This study aimed to develop and validate a radiomic nomogram for the prediction of secondary LOR to IFX in patients with Crohn’s disease (CD).

Patients and Methods

A total of 186 biologic-naive patients diagnosed with CD between September 2016 and June 2019 were enrolled. Secondary LOR was determined during week 54. Computed tomography enterography (CTE) texture analysis (TA) features were extracted from lesions and analyzed using LIFEx software. Feature selection was performed by least absolute shrinkage and selection operator (LASSO) and ten-fold cross validation. A nomogram was constructed using multivariable logistic regression, and the internal validation was approached by ten-fold cross validation.

Results

Predictors contained in the radiomics nomogram included three first-order and five second-order signatures. The prediction model presented significant discrimination (AUC, 0.880; 95% CI, 0.816–0.944) and high calibration (mean absolute error of = 0.028). Decision curve analysis (DCA) indicated that the nomogram provided clinical net benefit. Ten-fold cross validation assessed the stability of the nomogram with an AUC of 0.817 and an accuracy of 0.819.

Conclusion

This novel radiomics nomogram provides a predictive tool to assess secondary LOR to IFX in patients with Crohn’s disease. This tool will help physicians decide when to switch therapy.

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.

Management of patients with Intestinal Bowel Disease and COVID-19: A review of current evidence and future perspectives

The COVID-19 pandemic has been a challenge for countries and health professionals worldwide. Viral entry by ACE-2 receptor and an excessive activation of the immune system are key to understand both incidence and severity of disease. Inflammatory Bowel Disease (IBD) represents a special condition associated with an inordinate response of the immune system to external agents. IBD treatments have been associated to an increased risk of bacterial and viral infections. This has raised the question of possible higher incidence and severity of COVID-19 infection in IBD patients. Several papers have been published during this year of pandemic to answer that question. Moreover, COVID-19 vaccination offers great promise in controlling infection in patients with IBD. Based on current evidence, patients with IBD do not have a higher incidence of COVID-19 than the general population, and they do not have worse disease evolution. Advanced age and presence of a greater number of comorbidities have been associated with worse outcomes, similar to the general population. Corticosteroids are associated to an increased risk of COVID-19 infection, higher hospitalization rate and higher risk of severe COVID-19. 5-ASA/Sulfasalazine and Thiopurines have a possible increased risk of severe COVID-19, although studies are lacking. On the other hand, Anti-TNF may have a possible protective effect. It is recommended to maintain the treatment. Anti-IL-12/23, anti-integrins and tofacitinib have results comparable to anti-TNF. Based on the efficacy, expert recommendations, and the absence of other evidence, it is recommended that patients with IBD be vaccinated.

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

Background

Ultrasound (US) is an alternative to magnetic resonance enterography, and has the potential to significantly reduce waiting times, expedite clinical decision-making and improve patient experience. Point of care US is an advantage of the US imaging modality, where same day scanning, interpretation and treatment decisions can be made.

Aim

To systematically scope the literature on point of care US use in small bowel Crohn's disease, generating a comprehensive list of factors relating to the current understanding of clinical utility of this imaging modality.

Methods

Searches included MEDLINE, EMBASE, Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, clinicaltrial.gov,'TRIP' and Epistemonikos. Reference lists of included studies were hand searched. Search terms were searched for as both keywords and subject headings (MeSH) as appropriate. Searches were performed with the 'suggested search terms' and 'explode' selection, and restricted to 'human', 'adult' and 'English language' publications. No date limits were applied to be as inclusive as possible. Two investigators conducted abstract and full-text review. No formal quality appraisal process was undertaken; however, quality of sources was considered when reporting findings. A narrative synthesis was conducted.

Results

The review included 42 sources from the UK, Europe, Japan, Canada and the USA. Small bowel ultrasound (SBUS) has been shown to be as accurate in detecting the presence of small bowel Crohn's disease, is quicker, safer and more acceptable to patients, compared with magnetic resonance enterography. SBUS is used widely in central Europe and Canada but has not been embraced in the UK. Further research considering economic evaluation, clinical decision-making and exploration of perceived barriers to future implementation of SBUSs is required.

Small Bowel Adenocarcinoma Mimicking a Crohn's Attack

Small bowel adenocarcinoma (SBA) is a rare disease and presents with intermittent abdominal pain, weight loss, nausea, vomiting, and gastrointestinal bleeding. In cases with delayed diagnosis, intestinal obstruction or bowel perforation can also be observed. In our case, the patient presented with ileus after an operation that was diagnosed with SBA. After six cycles of chemotherapy, the patient went into complete remission.

Endoscopic and Histopathological Findings of the Esophagus, Stomach, and Duodenum in Patients with Crohn's Disease from a Reference Center in Bahia, Brazil

(1) The aim of the present study was to describe the endoscopic and histopathological findings in the esophagus, stomach, and duodenum in patients with Crohn's disease. (2) Methods: This was a cross-sectional study that included patients receiving treatment from the inflammatory bowel disease outpatient clinic. Esophagogastroduodenoscopies with biopsies of the stomach and proximal duodenum were performed. Presence of Helicobacter pylori bacteria was assessed by Giemsa staining. (3) Results: We included 58 patients. Erosive esophagitis was identified in 25 patients (43.1%), gastritis was diagnosed in 32 patients (55.2%) and erosive duodenitis was found in eight (13.8%). The most frequent histopathological finding in the H. pylori-positive group was increased inflammatory activity in the gastric body and antrum, with a predominance of mononuclear and polymorphonuclear cells. In turn, the most frequent finding in the H. pylori-negative group was chronic inflammation with predominance of mononuclear cells. Focally enhanced gastritis was identified in four patients (6.9%), all of whom were negative for H. pylori. Granulomas were not observed. H. pylori infection was present in 19 patients (32.8%). (4) Conclusions: Nonspecific endoscopic and histological findings were frequent in patients with Crohn's disease. Focally enhanced gastritis was uncommon and observed only in H. pylori-negative patients. The time from the diagnosis, patient age, and therapy in use may have influenced the nondetection of epithelioid granuloma.

Artificial intelligence in gastrointestinal endoscopy for inflammatory bowel disease: a systematic review and new horizons

INTRODUCTION

Since the advent of artificial intelligence (AI) in clinical studies, luminal gastrointestinal endoscopy has made great progress, especially in the detection and characterization of neoplastic and preneoplastic lesions. Several studies have recently shown the potential of AI-driven endoscopy for the investigation of inflammatory bowel disease (IBD). This systematic review provides an overview of the current position and future potential of AI in IBD endoscopy.

METHODS

A systematic search was carried out in PubMed and Scopus up to 2 December 2020 using the following search terms: artificial intelligence, machine learning, computer-aided, inflammatory bowel disease, ulcerative colitis (UC), Crohn's disease (CD). All studies on human digestive endoscopy were included. A qualitative analysis and a narrative description were performed for each selected record according to the Joanna Briggs Institute methodologies and the PRISMA statement.

RESULTS

Of 398 identified records, 18 were ultimately included. Two-thirds of these (12/18) were published in 2020 and most were cross-sectional studies (15/18). No relevant bias at the study level was reported, although the risk of publication bias across studies cannot be ruled out at this early stage. Eleven records dealt with UC, five with CD and two with both. Most of the AI systems involved convolutional neural network, random forest and deep neural network architecture. Most studies focused on capsule endoscopy readings in CD (n = 5) and on the AI-assisted assessment of mucosal activity in UC (n = 10) for automated endoscopic scoring or real-time prediction of histological disease.

DISCUSSION

AI-assisted endoscopy in IBD is a rapidly evolving research field with promising technical results and additional benefits when tested in an experimental clinical scenario. External validation studies being conducted in large and prospective cohorts in real-life clinical scenarios will help confirm the added value of AI in assessing UC mucosal activity and in CD capsule reading.

PLAIN LANGUAGE SUMMARY

Artificial intelligence for inflammatory bowel disease endoscopy Artificial intelligence (AI) is a promising technology in many areas of medicine. In recent years, AI-assisted endoscopy has been introduced into several research fields, including inflammatory bowel disease (IBD) endoscopy, with promising applications that have the potential to revolutionize clinical practice and gastrointestinal endoscopy.We have performed the first systematic review of AI and its application in the field of IBD and endoscopy.A formal process of paper selection and analysis resulted in the assessment of 18 records. Most of these (12/18) were published in 2020 and were cross-sectional studies (15/18). No relevant biases were reported. All studies showed positive results concerning the novel technology evaluated, so the risk of publication bias cannot be ruled out at this early stage.Eleven records dealt with UC, five with CD and two with both. Most studies focused on capsule endoscopy reading in CD patients (n = 5) and on AI-assisted assessment of mucosal activity in UC patients (n = 10) for automated endoscopic scoring and real-time prediction of histological disease.We found that AI-assisted endoscopy in IBD is a rapidly growing research field. All studies indicated promising technical results. When tested in an experimental clinical scenario, AI-assisted endoscopy showed it could potentially improve the management of patients with IBD.Confirmatory evidence from real-life clinical scenarios should be obtained to verify the added value of AI-assisted IBD endoscopy in assessing UC mucosal activity and in CD capsule reading.

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.

Management and outcomes of surgical patients with intestinal Behçet’s disease and Crohn’s disease in southwest China

BACKGROUND

Gastrointestinal involvement in Behçet's disease (GIBD) and Crohn’s disease (CD) are inflammatory diseases sharing a considerable number of similarities. However, different from CD, the operative and postoperative management of GIBD remains largely empirical because of the lack of comprehensive treatment guidelines.

AIM

To compare surgical patients with GIBD and those with CD in a medical center and identify notable clinical features and effective postoperative treatment for surgical patients with GIBD.

METHODS

We searched patients diagnosed with CD and GIBD who underwent operations for gastrointestinal complications from 2009 to 2015 at West China Hospital of Sichuan University. A total of 10 surgical patients with GIBD and 106 surgical patients with CD were recruited. Information including demographic data, medication, and operative and postoperative parameters were collected and analyzed. As the incidence of surgical GIBD is low, their detailed medical records were reviewed and compared to previous studies. Moreover, the prognoses of CD and GIBD were evaluated respectively between groups treated with biological and non-biological agents.

RESULTS

Indication for first surgery was often acute intestinal perforation for GIBD patients (7/10 vs 0/106, P < 0.001), whereas intestinal fistulae (0/10 vs 44/106, P = 0.013) and ileus (0/10 vs 40/106, P = 0.015) were the indications for surgical CD patients. Approximately 40% of patients with GIBD and 23.6% of patients with CD developed postoperative complications, 50% of patients with GIBD and 38.7% of patients with CD had recurrence postoperatively, and 40% (4/10) of patients with GIBD and 26.4% (28/106) of patients with CD underwent reoperations. The average period of postoperative recurrence was 7.87 mo in patients with Behçet's disease (BD) and 10.43 mo in patients with CD, whereas the mean duration from first surgery to reoperation was 5.75 mo in BD patients and 18.04 mo in CD patients. Surgical patients with GIBD more often used corticosteroids (6/10 vs 7/106, P < 0.001) and thalidomide (7/10 vs 9/106, P < 0.001) postoperatively, whereas surgical patients with CD often used infliximab (27/106), azathioprine, or 6-mercaptopurine (74/106) for maintenance therapy.

CONCLUSION

Patients suffering GIBD require surgery mostly under emergency situations, which may be more susceptible to recurrence and reoperation and need more aggressive postoperative treatment than patients with CD.

Gene Polymorphisms of NOD2, IL23R, PTPN2 and ATG16L1 in Patients with Crohn's Disease: On the Way to Personalized Medicine?

Genetic and environmental factors are involved in the pathogenesis of inflammatory bowel diseases (IBD). The study aimed at investigating the potential influence of single nucleotide polymorphisms (SNPs) NOD2 rs2066844, NOD2 rs2066845, NOD2 rs2066847, IL23R rs11209026, PTPN2 rs2542151, PTPN2 rs7234029, and ATG16L1 rs2241880 on the response to immunomodulatory therapies and disease course in Crohn’s disease (CD). This is an uncontrolled retrospective monocentric study including patients from the IBD outpatient clinic of Heidelberg University Hospital. Therapy responses and disease courses were related to genetic findings. 379 patients with CD were included. The presence of at least one PTPN2 rs7234029 risk allele was associated with nonresponse to anti-interleukin-12/23 treatment (89.9% vs. 67.6%, p = 0.005). The NOD2 rs2066844 risk allele was associated with a first-degree family history of colon cancer (12.7% vs. 4.7%, p = 0.02), the ATG16L1 rs2241880 risk allele with ileal CD manifestation (p = 0.027), and the IL23R rs11209026 risk allele with a higher rate of CD-related surgeries per disease year (0.08 vs. 0.02, p = 0.025). The results of this study underline the relevance of genetic influences in CD. The association of the PTPN2 rs7234029 risk allele with nonresponse to anti-interleukin-12/23 treatment in CD patients is a novel finding and requires further investigation.

Inflammatory bowel disease course in liver transplant versus non-liver transplant patients for primary sclerosing cholangitis: LIVIBD, an IG-IBD study

BACKGROUND

Data regarding the effect of orthotopic liver transplantation (OLT) for primary sclerosing cholangitis (PSC) on inflammatory bowel disease (IBD) course are scarce and conflicting.

AIMS

To compare the incidence of refractory IBD in two groups (OLT and non-OLT) of patients affected by IBD and PSC.

METHODS

An observational, multicentre, cohort retrospective study was conducted by the Italian Group for the study of IBD in Italy. The primary outcome was the need for biologic therapy or bowel resection for medically refractory IBD or hospitalization due to IBD relapse during the follow-up. Secondary outcomes were rate of colonic dysplasia, colorectal cancer, other solid tumours, lymphoma.

RESULTS

Eighty-four patients were included in the study. The primary outcome was not different between OLT and non-OLT groups (11/27, 40.7%, versus 20/57, 35.1%, respectively, p = 0.62). The lymphoma and other tumours (thyroid cancer, kidney cancer, ileal tumour, ovarian cancer, cervical cancer) rates were significantly higher in the OLT group (p = 0.04 and p = 0.005, respectively), at the limit of statistical significance for high-grade colonic dysplasia (p = 0.06).

CONCLUSION

OLT in patients affected by IBD and PSC is not a risk factor for a more severe IBD course, but it is associated with a higher occurrence of cancer.

Utility of noncontrast MRI in the detection and risk grading of gastrointestinal stromal tumor: a comparison with contrast-enhanced CT

BACKGROUND

Recently developed adjuvant therapies for gastrointestinal stromal tumor (GIST) have been shown to improve patient survival. Guidelines currently recommend contrast-enhanced computed tomography (CECT) for GIST detection and surveillance. Patients with moderate-to-high risk GISTs require more frequent surveillance due to a higher 5-year recurrence rate. Our study aimed to compare noncontrast magnetic resonance imaging (MRI) with CECT for GIST detection, and evaluate volumetric apparent diffusion coefficients (ADCs) for risk stratification of GIST.

METHODS

We retrospectively enrolled 83 patients with histopathologically confirmed GISTs for lesion detection efficiency analysis between noncontrast MRI and matched CECT studies. A 5-point scale was used by two independent reviewers to determine if the lesion was present or absent. Another cohort, comprising 28 patients with pathologically confirmed primary GISTs, was further screened for risk stratification, with a comparison of volumetric ADC parameters between the pathologically very-low-to-low risk and moderate-to-high risk GIST patients.

RESULTS

For identifying GISTs, the sensitivity and specificity of noncontrast MRI were 83.6% and 89.3% for reader 1 respectively, and 81.8% and 92.9% for reader 2 respectively; the sensitivity and specificity of CECT were 76.4% and 89.3% for reader 1 respectively, and 76.4 and 78.6% for reader 2 respectively. Tumor volumetric ADC histogram parameters, including ADCmax, ADCstdev, 90th and 95th percentiles, inhomogeneity, and entropy, were positively correlated with a higher risk grade of GIST (r=0.421-0.758). The receiver operator characteristic curve analysis showed ADCmax achieved the highest area under the curve value of 0.938 for discriminating very-low-to-low risk versus moderate-to-high risk GISTs.

CONCLUSIONS

Noncontrast MRI was an efficient technique for identifying GIST patients. The combination of CECT and noncontrast MRI can improve the reliability of diagnosis. For patients with contraindications to CECT, noncontrast MRI may be a comparable alternative. Volumetric ADC histogram parameters may be useful in differentiating very-low-to-low risk from moderate-to-high risk primary GISTs.