Small Bowel Crohn's Disease Research Articles

Infliximab Trough Levels Are Associated With Endoscopic Remission in Small Bowel Crohn's Disease.

To identify the association between infliximab trough levels (ITL) and treatment outcomes in small bowel Crohn's disease (SB-CD). Higher ITL are associated with favorable treatment outcomes in CD. However, the association between ITL and SB-CD treatment outcomes are rarely studied. This was a retrospective cross-sectional study. Patients with SB-CD who received maintenance infliximab therapy were recruited, and treatment efficacy was evaluated through double balloon endoscopy. Serum samples were collected to test ITL. The primary outcome was endoscopic remission (ER), which is defined as a Simple Endoscopic Score of Crohn's disease (SES-CD) of <3. The secondary outcome was mucosal healing (MH) (SES-CD: 0) and endoscopic response (SES-CD decreased by 50% from baseline). The factors associated with ER were also explored through logistic regression analysis. In total, 111 patients with SB-CD were enrolled. Forty-seven patients (42.3%) achieved ER. Median ITL was significantly higher in patients with ER than patients without ER (2.74 vs. 1.12µg/mL, P<0.01). In a multivariate model, an elevated ITL was the only independent factor associated with an increased probability of ER [odds ratio (OR): 1.24, 95% CI: 1.08-1.43, P=0.003]. The cutoff level of ITL used to predict ER with a specificity of >80% was 3.45µg/mL, and the area under the curve (AUC) was 0.790. Meanwhile, the AUC cutoff to predict MH and endoscopic responses was 0.767 and 0.759, respectively. There was a significant association between higher ITL and favorable SB-CD treatment outcomes.

Quantitative assessment of ultrasound microvessel imaging in Crohn's disease: correlation with pathological inflammation.

Ultrasound microvessel imaging (UMI) may offer noninvasive, highly sensitive microvessel imaging for assessing Crohn's disease (CD). However, a quantification metric that demonstrates a strong correlation with pathological inflammation is preferred. The objective was to determine if UMI can enhance IBD imaging interrogations. UMI was performed on bowel wall segments from patients with CD requiring surgery (n = 55 patients). The vessel-length ratio (VLR) measured by UMI was compared with that obtained using color flow imaging (CFI) and with a histopathologic standard evaluated on all bowel layers. Correlations between VLR and pathological inflammation and receiver operating characteristic (ROC) curves between different groups were analyzed to demonstrate the advantages of VLR with UMI. The correlation between VLR from UMI and pathological inflammation (R = 0.80) outperformed that of VLR from CFI (R = 0.59). UMI showed a significant difference (p < 0.01) between mild and non-mild inflammation cases, while CFI could not (p = 0.014). In the ROC analysis, VLR with UMI demonstrated an area under the curve (AUC) of 0.93, compared to the AUC of 0.80 for VLR with CFI, indicating better identification of pathological inflammation between mild and non-mild cases. For a sub-cohort of patients with stricture without penetrating complications (n = 19), VLR using UMI also showed better correlation (R = 0.93) with pathological inflammation scores and a higher AUC (0.96) than those of VLR using CFI (R = 0.66 and 0.88, respectively). UMI enhances vessel detection sensitivity compared to CFI and more accurately reflects transmural inflammation in small bowel Crohn's disease. VLR using UMI strongly correlates with pathological inflammation, distinguishing between mild and non-mild cases, notably including patients with stricture without penetrating complications. Question Bowel wall thickness and Limberg score from ultrasound are insufficient quantitative metrics for reliable diagnosis of inflammation severity for Crohn's disease. Findings Ultrasound microvessel imaging (UMI) with vessel-length ratio (VLR) is strongly correlated with pathological inflammation and had improved distinction between mild and non-mild inflammation cases. Clinical relevance UMI with VLR has the potential to enhance clinicians' ability to assess disease activity and evaluate therapeutic responses, thereby improving Crohn's disease patient outcomes.

Combined [18F]-FDG PET-MR Imaging: A promising tool for diagnostics of small bowel Crohn's disease.

Introduction Diagnostics of small bowel Crohn's disease (CD) can be difficult. Combined positron emission tomography-magnetic resonance enterography (PET-MRE) can be used to evaluate intestinal metabolism, but clinical use has been limited due to accessibility, costs, absence of standardized methods and diagnostic thresholds. Our aim was to show that combined PET-MRE can be used to diagnose active small bowel CD. Methods We performed a fusion PET-MRE-scan with [18F]-FDG-tracer to 30 patients with suspected small bowel CD in colonoscopy. Standardized uptake values (SUV) were measured from small bowel. The diagnosis was confirmed with small bowel capsule endoscopy. Clinicians chose appropriate medication to each patient blinded from SUV-results. Endoscopic, laboratory and MRE-findings were investigated in relation to SUV. Results Fusion PET-MRE outperformed MRE in diagnostic accuracy. Patients diagnosed with CD (N=24) had higher SUV than patients not diagnosed with CD (N=6) (3.34 vs. 1.84, p=0.022). A diagnostic cut-off at SUV at 2.5. could be used (AUROC=0.81). A higher SUV predicts need for immunosuppressive medication (p=0.0026) and biologics (p=0.0005). SUV correlates positively with SES-CD-score (Simple Endoscopic Score for Crohn's Disease), fecal calprotectin and CRP and negatively with Hb and serum albumin. Conclusion In future, [18F]-FDG PET-MRE can be used in diagnostics of small bowel CD as a safe alternative for capsule endoscopy. High SUV can predict a more progressive disease course and need for more advanced therapies.

Recurrence rates after strictureplasty for small bowel Crohn's disease remain high in the era of biologics.

Despite advancements in therapeutic options for Crohn's disease (CD), strictureplasty is a mainstay bowel-preserving technique for small bowel CD. We sought to audit international practice across three high-volume centres since the widespread use of biologic medication. A retrospective audit was performed for all strictureplasties undertaken for small bowel CD, over a 15-year period (2006-2021), in three high-volume centres in the United Kingdom and Italy. Primary endpoints were clinical recurrence and reoperation for recurrence. In all, 123 patients were included; 58% were men, 25% smoked and 60% had previous abdominal surgery for CD. Median age was 40 years (interquartile range 30-52 years), mean body mass index 22 (15-31) and median disease duration 138 months (81-255 months). 42% had been treated with biologics preoperatively. In total 338 strictureplasties were performed in 123 patients, with a median of two per patient (interquartile range 1-3). Complications occurred in 35%, with 8% scoring Clavien-Dindo Grade 3. There were no Grade 4/5 complications. Postoperative biologic treatment was administered to 84/123 patients (68.3%). Median follow-up was 54 months. 41/123 patients (33.3%) developed clinical recurrence. Reoperation for recurrent stricturing was performed in 26/123 patients (21%). Clinical recurrence and reoperation rates were significantly higher in patients who continued to smoke after their index surgery. Strictureplasty remains a safe and effective surgical treatment for small bowel CD. Recurrence and reoperation rates remain high, regardless of postoperative biologic therapy. Smoking significantly increases the risk of recurrence.

International expert guidance for defining and monitoring small bowel strictures in Crohn's disease on intestinal ultrasound: a consensus statement

Diagnostic imaging using CT enterography, magnetic resonance enterography, and intestinal ultrasound are important tools in evaluating stricturing Crohn's disease. Definitions of strictures have been developed for CT enterography and magnetic resonance enterography. However, expert recommendations for definitions and treatment response of strictures on intestinal ultrasound are not available. The aim of this study was to standardise definitions, diagnosis, and treatment response criteria in small bowel stricturing Crohn's disease on intestinal ultrasound. Using modified RAND-University of California Los Angeles Appropriateness Method, a diverse expert panel of 13 gastroenterologists, seven radiologists, and two patient representatives was assembled. A total of 466 statements on definitions and response to therapy of stricturing Crohn's disease on intestinal ultrasound were generated from a systematic review and from expert opinion, with subsequent rating for appropriateness. Two rounds of voting with an interposed survey result discussion were performed. Statements were classified as inappropriate, uncertain, or appropriate based on the median panel rating and degree of disagreement. Appropriateness was rated using a nine-point Likert scale (1 being inappropriate, 9 being highly appropriate). A naive or anastomotic small bowel Crohn's disease stricture on intestinal ultrasound is defined by the combination of bowel wall thickening, luminal narrowing, and pre-stenotic dilation. Bowel wall thickness is defined as being more than 3 mm. Luminal narrowing is defined as either a luminal diameter reduction of more than 50% in the narrowest area and relative to a normal adjacent bowel loop, or a luminal diameter of less than 1 cm. Pre-stenotic dilation is defined as more than 2·5 cm or an increase in bowel diameter relative to a normal adjacent bowel loop. Definitions for grading hyperaemia, inflammatory fat, wall stratification, intestinal ultrasound machine technical parameters, and image acquisition were also devised. Treatment response of strictures was defined as reduction in stricture length, bowel wall thickening, luminal narrowing, pre-stenotic dilation, and motility abnormalities. To our knowledge, this is the first intestinal ultrasound appropriateness rating exercise conducted for defining, diagnosing, and measuring response to therapy in small bowel stricturing Crohn's disease and informs future clinical use and intestinal ultrasound index development for clinical trials. Leona M and Harry B Helmsley Charitable Trust.

Does HLA-DQA1*05 carriage have a greater impact on the outcome of infliximab therapy for isolated small-bowel Crohn's disease?

Carriage of HLA-DQA1*05 is thought to increase the formation of anti-tumour necrosis factor alpha (TNF-α) antibodies, reducing the drug efficacy in Crohn's disease (CD) patients. However, little data are currently available for small-bowel Crohn's disease (SB-CD). A specific assessment of the impact of HLA-DQA1*05 on the clinical response to treatment with infliximab (IFX), a TNF-α antagonists, in SB-CD patients is necessary. We conducted a single-center retrospective study that included 106 SB-CD patients treated with IFX. The serum samples were collected for antibodies to infliximab (ATI) testing and HLA-DQA1*05 genotyping. Double-balloon enteroscopy (DBE) was performed following the IFX treatment, with endoscopic outcomes evaluated using the partial simple endoscopic score for CD (pSES-CD), whereas the clinical response was assessed with the Crohn's disease activity index (CDAI). Multivariate logistic regression and multivariate COX regression analyses were employed to analyze the correlation of the HLA-DQA1*05 genotypes with other clinical variables. In this study, 30.2% of SB-CD patients carried the HLA-DQA1*05 allele, which significantly increased their risk of ATI generation (odds ratio [OR]=2.337, p=.043), but it was not associated with the clinical response to IFX and drug persistence (OR=2.356, p=.145; OR=0.457, p=.249). The endoscopic remission rates were 40.6% (13/32) and 55.4% (41/74) in HLA-DQA1*05 carriers and non-carriers, respectively. HLA-DQA1*05 was not associated with endoscopic remission (OR=0.684, p=.414). The HLA-DQA1*05 variant is identified as a significant risk factor of ATI formation in Chinese patients with SB-CD, but is not associated with the clinical response of IFX treatment and endoscopic remission of SB lesions.

Pro-motility Preparation Protocol May Reduce the Rates of Failed Patency Capsule Among Patients with Crohn’s Disease in Clinical Remission

BackgroundPatency capsule (PC) ingestion is commonly used to minimize capsule retention in high-risk patients with Crohn’s disease (CD). However, false-positive rates remain high, precluding the use of video capsule endoscopy (VCE). We aimed to compare the efficacy of two preparation protocols in reducing failed PC rates in patients with CD.MethodsThis bi-center retrospective case–control study included adult patients with small-bowel CD in clinical remission who underwent PC ingestion. The pro-motility group followed a low-residue diet, then a clear fluid diet, and took bisacodyl after ingestion, while the control group followed only a clear fluid diet. The primary outcome was failed PC, defined as the absence of PC excretion or presence on abdominal X-ray at 30 h post-ingestion. Multivariable logistic regression was used to identify predictors of failed PC.ResultsAmong 273 patients (83 in the pro-motility group, 190 controls), the pro-motility group was older (median 36 [27–48] vs. 31 [24–43], p = 0.012) and had a lower rate of B2/3 disease phenotype (32.5 vs. 53.1%, p = 0.002) compared to controls. The pro-motility group also had a lower failed PC rate (12.0 vs. 24.7%, p = 0.023). Longer disease duration (adjusted odds ratio (AOR) 1.053, 95% confidence interval (CI) 1.016–1.091, p = 0.005) increased the odds of failed PC, while the pro-motility protocol was protective (AOR 0.438, 95% CI 0.200–0.956, p = 0.038), outweighing the influence of B2/3 disease phenotype (AOR 1.743, 95% CI 0.912–3.332, p = 0.093).ConclusionsThe pro-motility preparation protocol could substantially improve the success rates of the small-bowel patency test in patients with CD undergoing PC ingestion, potentially reducing the risk of capsule retention and associated complications.

Evaluation of Deep Remission with Through-The-Scope Catheter-Based Endoscopic Ultrasound during Double Balloon Enteroscopy in Small Bowel Crohn’s Disease

Evaluation of deep remission in Crohn's disease (CD) can be challenging when the disease is confined to the small intestine. The aim of this study was to evaluate the effectiveness of through-the-scope (TTS) endoscopic ultrasound (EUS) during Double-balloon enteroscopy (DBE) in distinguishing small-bowel CD patients in endoscopic remission from those with active disease. Patients who underwent DBE-EUS were divided into groups of endoscopic remission and endoscopic activity according to segmental Simple Endoscopic Score for Crohn's Disease (SES-CD). Thickness of small intestinal wall layers and other parameters were evaluated by EUS. EUS using the ultrasonic catheter probe via DBE showed that the total wall thickness (TWT) and submucosal thickness (SMT) of the small intestine in the active group were significantly greater than those in the remission group (TWT 3.84±1.02 vs 2.42±0.25mm, SMT 1.23±0.34 vs 0.79±0.13mm, respectively, p<0.001). Cut-off values of 2.65 mm for TWT and 0.95 mm for SMT can distinguish active small-bowel CD from inactive disease (Sensitivity 91.5%, Specificity 80.8% and Sensitivity 70.2%, Specificity 88.6%, respectively). The correlation analysis revealed a significant positive correlation between TWT and SES-CD (r=0.930, p<0.001). Furthermore, TWT was strongly correlated with FC (r=0.861, p<0.001) and CDAI (r=0.805, p<0.001). Similar results were observed for SMT. EUS using an ultrasonic catheter probe during DBE is effective in evaluation of both mucosal and transmural healing in small-bowel CD patients. DBE-EUS could become an important tool in the management of patients with small-bowel CD.

Quantitative MRI in children with Crohn's disease - where do we stand?

Crohn's disease (CD) is a chronic inflammatory condition that affects the gastrointestinal tract, particularly the ileum and colon. This disease is characterized by recurrent bouts of intestinal inflammation with subsequent bowel wall damage, including scarring (i.e., fibrosis) and abnormal smooth muscle proliferation. MR enterography, an MRI examination tailored to assess the small bowel, is a first-line diagnostic tool for diagnosing CD in children, characterization and monitoring of disease severity and extent, and assessment of disease-related complications. To date, such MRI evaluations have been mostly qualitative, which can adversely impact diagnostic performance and inter-radiologist agreement. Quantitative MRI methods have been shown to aid in the evaluation of a variety of medical conditions and have been increasingly investigated in children and adults with CD. In CD, such objective techniques have been used to assist with diagnosis, assess treatment response, and characterize bowel wall histologic abnormalities. In the current work, we will review quantitative MRI methods for detecting and measuring intestinal active inflammation (MRI-based scoring systems, T1 relaxation mapping, diffusion-weighted imaging, intra-voxel incoherent motion, mesenteric phase contrast), bowel wall damage (magnetization transfer), and motility (quantitative cine imaging) in small bowel CD, with an emphasis on the pediatric population.

Unusual causes of Small bowel obstruction: a review of the literature and revisited cross-sectional imaging checklist.

Intestinal obstruction is a common surgical emergency with high morbidity and mortality. Patients presenting with features of small bowel obstruction need urgent evaluation to avoid complications such as bowel gangrene, perforation, or peritonitis. Imaging is necessary in most cases of suspected bowel obstruction, to take an appropriate decision, for apt patient management. Among the common causes of small bowel obstruction, adhesions, external herniae, malignancies, and Crohn's disease top the chart. Imaging helps in determining the presence of obstruction, the severity of obstruction, transition point, cause of obstruction, and associated complications such as strangulation, bowel gangrene, and peritonitis. This review is based on the cases with unusual causes of bowel obstruction encountered during our routine practice and also on the extensive literature search through the standard textbooks and electronic databases. Through this review we want our readers to have sound knowledge of the imaging characteristics of the uncommon yet important causes of bowel obstruction. We have also revisited and structured a checklist to simplify the approach while reporting a suspected case of small bowel obstruction. Imaging plays a key role in the diagnosis of small bowel obstruction and in determining the cause and associated complications. Apart from the common causes of small bowel obstruction, we should also be aware of the uncommon causes of small bowel obstruction and their imaging characteristics to make an accurate diagnosis and for apt patient management.

The Epidemiology and Clinical Management of Short Bowel Syndrome and Chronic Intestinal Failure in Crohn's Disease in Italy: An IG-IBD Survey.

Limited data exist on the epidemiology and clinical management of short bowel syndrome (SBS) and chronic intestinal failure (CIF) in Crohn's disease (CD). This study aimed to evaluate these aspects in Italy. Members of the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD) were invited to complete a cross-sectional web survey. A subgroup analysis examined the influence of different clinical settings on SBS and CIF management in CD. A total of 47/128 (36.7%) IG-IBD centers participated. Among them, 31.9% were teduglutide (TED) prescribers, and 48.9% were academic centers. The median estimated prevalence of CIF among small bowel CD patients was 1%, and it was significantly higher in academic centers (2.0% [IQR 1-5%] vs. 0.13% [IQR 0-1%], p = 0.02). Seventy-eight percent of centers managed fewer than 10 SBS and CD patients. Routine small bowel measurement and nutritional assessment were performed in only 15% and 42.6% of centers, respectively. TED was prescribed by 12 centers to 35 patients, with a treatment success rate exceeding 50% in 81.8% of centers. The estimated prevalence of CIF in CD patients with small bowel involvement in Italy is 1%. The diagnosis and management practices for SBS and CIF are suboptimal, and TED use is limited.

The Role of Small-Bowel Capsule Endoscopy in the Diagnostic Algorithm of Complicated Perianal Disease.

Complicated perianal disease (cPD) may be the sole presentation of Crohn's disease (CD). The role of small-bowel capsule endoscopy (SBCE) in the diagnostic algorithm of cPD is unclear. We aimed to evaluate the role of SBCE as a diagnostic tool, in patients with cPD, after a negative standard workup for CD. A multicenter, retrospective, cross-sectional study, in patients with cPD, and negative standard workup for CD (ileocolonoscopy and cross-sectional imaging), who underwent SBCE for suspected CD. Demographics, biomarkers, and the Lewis Score (LS) were recorded and analyzed. An LS ≥ 135 was considered a positive SBCE for diagnosing CD. Ninety-one patients were included: 65 (71.4%) males; median age: 37 (29-51) years; cPD duration: 25.1 (12.5-66.1) months. Positive SBCE: 24/91 (26.4%) patients. Fecal calprotectin (FC) positively correlated with LS (r = 0.81; p < 0.001). FC levels of 100 µg/g and 50 µg/g had a sensitivity of only 40% and 55% to rule out small-bowel CD, with a negative predictive value (NPV) of only 76% and 80%, respectively. SBCE contributed to CD diagnosis in a quarter of patients with cPD after a negative standard workup. FC levels correlated with the degree of inflammation defined by the LS. However, the NPV of FC was low, suggesting that SBCE should be considered for patients with cPD even after a negative standard workup.

Small bowel Crohn's disease: Proximal lesions linked to increased inflammation and biologic treatment needs

ObjectiveCrohn's disease (CD) is heterogeneous, and proximal involvement in the small bowel (SB) is associated with worse outcomes. Nonetheless, studies on the impact of duodenal and jejunal lesions in SB CD are limited. This study aimed to investigate the clinical characteristics and outcomes of individuals diagnosed with SB CD, comparing those with and without proximal inflammation. MethodsA cohort of 53 treatment-naive SB CD patients that underwent Capsule Endoscopy at diagnosis were retrospectively selected. The inflammatory activity was quantified using the Lewis Score for each SB tertile. ResultsThirty-seven (69.8%) patients displayed inflammatory activity in the first and/or second tertile together with third tertile involvement (Proximal+T3 group). Sixteen (30.2%) had inflammation in the third tertile only (T3 group). Individuals in the Proximal+T3 group had a higher risk for moderate-to-severe inflammation (OR 4.93, 95% CI: 1.3–18.3, p=0.013). A subgroup analysis for those with mild inflammatory activity showed that individuals in the Proximal+T3 group initiated biologic drugs more often (OR 11, 95% CI: 1.1–109.7, p=0.036). ConclusionProximal SB lesions are associated with increased inflammatory activity, necessitating more frequent use of biologics in patients with mild disease. Early detection of proximal SB CD with Capsule Endoscopy may contribute to timely treatment.

Crohn's Disease: Radiological Answers to Clinical Questions and Review of the Literature.

Background: Crohn's disease (CD) is a chronic, progressive inflammatory condition, involving primarily the bowel, characterized by a typical remitting-relapsing pattern. Despite endoscopy representing the reference standard for the diagnosis and assessment of disease activity, radiological imaging has a key role, providing information about mural and extra-visceral involvement. Methods: Computed Tomography and Magnetic Resonance Imaging are the most frequently used radiological techniques in clinical practice for both the diagnosis and staging of CD involving the small bowel in non-urgent settings. The contribution of imaging in the management of CD is reported on by answering the following practical questions: (1) What is the best technique for the assessment of small bowel CD? (2) Is imaging a good option to assess colonic disease? (3) Which disease pattern is present: inflammatory, fibrotic or fistulizing? (4) Is it possible to identify the presence of strictures and to discriminate inflammatory from fibrotic ones? (5) How does imaging help in defining disease extension and localization? (6) Can imaging assess disease activity? (7) Is it possible to evaluate post-operative recurrence? Results: Imaging is suitable for assessing disease activity, extension and characterizing disease patterns. CT and MRI can both answer the abovementioned questions, but MRI has a greater sensitivity and specificity for assessing disease activity and does not use ionizing radiation. Conclusions: Radiologists are essential healthcare professionals to be involved in multidisciplinary teams for the management of CD patients to obtain the necessary answers for clinically relevant questions.

Leveraging existing mid-end ultrasound machine for point-of-care intestinal ultrasound in low-resource settings: Prospective, real-world impact on clinical decision-making.

Point-of-care ultrasound (POCUS) has transformed inflammatory bowel disease (IBD) management, but the cost to purchase high-end equipment can be prohibitive. To assess prospectively the feasibility of POCUS using pre-existing mid-end ultrasound equipment without incurring additional cost. Consecutive IBD patients underwent POCUS with or without faecal calprotectin (FCP) using a mid-end ultrasound machine. If POCUS with or without FCP could not guide management, we performed additional ileocolonoscopy or cross-sectional imaging. We evaluated the impact of POCUS on IBD management and its correlation with ileocolonoscopy or cross-sectional imaging. We analysed pregnant, paediatric and post-operative patients separately. Among 508 patients with IBD, we analysed 419 (60.4% Crohn's disease [CD]; 61.3% male, age [years]: 36 [18-78]) undergoing 556 POCUS sessions. POCUS with or without FCP independently influenced clinical management in 42.8% of patients with CD and 49.7% with ulcerative colitis (UC). POCUS helped avoid colonoscopy in 51.4% of patients with CD and 51.8% with UC, and cross-sectional imaging in 38.1% of suspected active small bowel CD. In patients with additional diagnostics, POCUS-based decisions remained unchanged in 81.2% with CD and 85% with UC. Sensitivity and specificity of POCUS compared to ileocolonoscopy were 80% and 94.4% for CD and 80.8% and 92.8% for UC, respectively. Sensitivity and specificity compared to cross-sectional imaging were 87.2% and 87.5%, respectively. POCUS using existing mid-end ultrasound equipment in low-resource settings influenced IBD clinical decision-making with excellent accuracy, often avoiding colonoscopy and cross-sectional imaging.

Quantitative Magnetic Resonance Imaging (qMRI) of the Small Bowel in Crohn's Disease: State-of-the-Art and Future Directions.

Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract in which repeated episodes of acute inflammation may lead to long-term bowel damage. Cross-sectional imaging is used in conjunction with endoscopy to diagnose and monitor disease and detect complications. Magnetic resonance imaging (MRI) has demonstrable utility in evaluating inflammatory activity. However, subjective interpretation of conventional MR sequences is limited in its ability to fully phenotype the underlying histopathological processes in chronic disease. In particular, conventional MRI can be confounded by the presence of mural fibrosis and muscle hypertrophy, which can mask or sometimes mimic inflammation. Quantitative MRI (qMRI) methods provide a means to better differentiate mural inflammation from fibrosis and improve quantification of these processes. qMRI may also provide more objective measures of disease activity and enable better tailoring of treatment. Here, we review quantitative MRI methods for imaging the small bowel in CD and consider the path to their clinical translation. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

Discrimination of pediatric cryptogenic multifocal ulcerous stenosing enteritis from small bowel Crohn's disease and gastrointestinal tuberculosis: A retrospective study (with videos).

Cryptogenic multifocal ulcerous stenosing enteritis (CMUSE) is a rare entity that mimics various inflammatory strictures of the small intestine. Pediatric literature is scarce. We analyzed the clinical, radiological, endoscopic and histopathological features of children with CMUSE that differentiate it from small bowel Crohn's disease (SBCD) and gastrointestinal tuberculosis (GITB). CMUSE was diagnosed by the following criteria: (1) unexplained small bowel strictures with superficial ulcers, (2) chronic/relapsing ulcers of small bowel after resection, (3) no signs of systemic inflammation, (4) absence of other known etiologies of small bowel ulcers. SBCD and GITB were diagnosed based on standard criteria. The clinical features, laboratory parameters, radioimaging, endoscopy (including video capsule endoscopy [VCE], intra-operative endoscopy), histopathological features and treatment outcome were noted. Out of 48,CMUSE was diagnosed in 13 (27%) isolated small bowel and ileocecal strictures, while GITB and SBCD accounted for 41% and 21% cases, respectively. Common presentations were sub-acute obstruction (46%), obscure gastrointestinal bleeding (38%) and protein-losing enteropathy (38%). CMUSE patients had significantly longer disease duration compared to SBCD and GITB (p < 0.001). SBCD (90.0%) and GITB (85%) cases had elevated C-reactive protein (CRP), none with CMUSE had elevated CRP (p < 0.001). The disease was localized in jejunum (100%) and proximal ileum (56%) in CMUSE, ileocecal region (85%) in GITB, but evenly distributed in small intestine in SBCD. Endoscopy showed evenly placed, superficial, circumferential ulcers with strictures in CMUSE, deep linear ulcers in SBCD and circumferential ulcers in GITB. Upfront immunosuppression was given in four; three (75%) of them relapsed. Only surgery was done in three with one (25%) having relapse. Upfront surgery followed by immunosuppression was used in six, but all relapsed and two required repeat surgery. CMUSE is important but underdiagnosed in children. Lack of constitutional symptoms, normal inflammatory parameters and characteristic ulcers with strictures helped in differentiating CMUSE from GITB and SBCD.

Diagnostic Value of 3.0 T Magnetic Resonance Imaging in Active Crohn's Disease.

Magnetic resonance enteroclysis (MRE) has been widely applied to diagnose Crohn's disease (CD). Magnetic resonance (MR) at 3.0 T improves signal-to-noise ratio (SNR), shortens image acquisition time, and shows more advantages. This study aimed to retrospectively analyze the diagnostic value of 3.0 T MR imaging for active CD. 48 CD patients hospitalized in our hospital from January 2021 to December 2022 were selected as the study subjects. These 48 CD patients underwent both double-balloon enteroscopy and 3.0 T MRE. All patients' arterial phase signal, venous phase signal, bowel wall, and bowel lumen of MRE were observed to identify whether they suffered from active CD. Based on the results of enteroscopy, the number of true positives, true negatives, false negatives, and false positives diagnosed by MRE were screened; next, the diagnostic accuracy, sensitivity, and specificity of MRE in assessing active CD were calculated. Of the 48 patients, 39 were diagnosed with small bowel CD by MRE, which was not significantly different from the results of enteroscopy (P>0.05). According to MRE diagnostic results, the arterial phase predominantly presented high signal intensity, and the venous phase mainly presented low signal intensity or isointensity. Small bowel CD lesions were primarily characterized by bowel wall thickening, rare pneumatosis enhancement of the bowel wall, bowel lumen pneumatosis or dilatation, and rare strictures. Besides, MRE presented an accuracy of 93.75%, sensitivity of 97.37%, and specificity of 80.00% in diagnosing CD. 3.0 T MR imaging has diagnostic value for active CD and shows certain clinical application value.</P>.

A global consensus on the definitions, diagnosis and management of fibrostenosing small bowel Crohn's disease in clinical practice.

Fibrostenosis of the small bowel is common in patients with Crohn's disease. No consensus recommendations on definition, diagnosis and management in clinical practice are currently available. In this Consensus Statement, we present a clinical practice RAND/UCLA appropriateness study on the definition, diagnosis and clinical management of fibrostenosing Crohn's disease. It was conducted by a panel of 28 global experts and one patient representative. Following a systematic literature review, 526 candidate items grouped into 136 questions were generated and subsequently evaluated for appropriateness. Strictures are best defined as wall thickening, luminal narrowing and prestenotic dilation. Cross-sectional imaging is required for accurate diagnosis of fibrostenosing Crohn's disease, and itis recommended before making treatment decisions. It should also assess the degree of inflammation in the bowel wall. Multiple options for medical anti-inflammatory, endoscopic and surgical therapies were suggested, including follow-up strategies following therapy. This Consensus Statement supports clinical practice through providing guidance on definitions, diagnosis and therapeutic management of patients with fibrostenosing small bowel Crohn's disease.

Prospective characterization of intestinal MRI intravoxel incoherent motion in pediatric and young adultpatients with newly diagnosed small bowel Crohn's disease.

MRI diffusion-weighted imaging (DWI) is commonly used in MR enterography protocols for assessment of intestinal inflammation in patients with Crohn's disease. The intravoxel incoherent motion (IVIM) approach to DWI has been proposed as a more objective approach, providing quantitative parameters that reflect water diffusivity (D), blood flow (D*), and perfusion fraction (f). We aimed to determine if DWI-IVIM metrics from the terminal ileum in patients with newly diagnosed Crohn's disease differ from healthy participants and change in response to biologic medical therapy. In this prospective case-control study, 20 consecutive pediatric patients (mean age = 14years ± 2 [SD]; eight females) with newly diagnosed ileal Crohn's disease and 15 pediatric healthy participants (mean age = 18years ± 4 [SD]; eight females) underwent research MRI examinations of the small bowel between 12/2018 and 10/2021. Participants with Crohn's disease underwent MR studies at baseline, 6weeks, and 6months following initiation of anti-TNF-alpha therapy, whereas control participants underwent one research MRI examination. The MRI protocol included a DWI-IVIM sequence with nine b-values and the IVIM parameters (D, D*, and f) were extracted. Unpaired t-tests and mixed-effects models were used for analyses. Mean IVIM D (P < 0.001), D* (P = 0.004), and f (P = 0.001) metrics were lower for Crohn's patients at the time of diagnosis compared to healthy participants. Mean IVIM f value increased over time in response to medical therapy (mean f at baseline, 22% ± 6%; 6weeks, 25% ± 7%; 6months, 29% ± 10%; P = 0.016). Mean IVIM D* value increased over time in response to treatment (mean D* at baseline, 10.9 ± 3.0 × 10-3 mm2/s; 6weeks, 11.8 ± 2.8 × 10-3 mm2/s; 6months, 13.3 ± 3.3 × 10-3 mm2/s; P = 0.047), while there was no significant change in mean IVIM D value (P = 0.10). MRI DWI-IVIM metrics in patients with ileal Crohn's disease change over time in response to biological therapy and help discriminate these patients from healthy participants.