Small Bowel Crohn's Disease Research Articles

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.

Patency 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. This 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. Among 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). The 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.

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.

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.

Efficacy of serum leucine-rich alpha-2 glycoprotein in predicting findings of Crohn's disease small bowel lesion in capsule endoscopy.

Small bowel capsule endoscopy (SBCE) is an evaluation method for small bowel (SB) lesions in Crohn's disease (CD). However, the relationship between SBCE findings and the serological biomarker leucine-rich alpha-2 glycoprotein (LRG) remains unclear. We aimed to establish appropriate cutoff values of LRG to predict the presence of SB lesions in CD through SBCE. Patients with CD with SB lesions who had undergone SBCE and LRG measurements 1 month before and after the SBCE were included. The LRG values for ulcers ≥0.5 cm and other inflammatory lesions noted in SBCE were determined using the Youden Index, and the sensitivity and specificity were calculated. Additionally, the correlation between the SBCE scores (CD Activity in Capsule Endoscopy) and LRG values was evaluated. Forty patients without active colorectal lesions were included in the study. When the cutoff value of LRG for SB ulcers ≥ 0.5 cm was set at 14 μg/mL, the sensitivity was 92.3%, specificity was 81.5%, positive predictive value (PPV) was 70.6%, and negative predictive value (NPV) was 95.7%. In contrast, an LRG cutoff value of 12 μg/mL without inflammatory findings had a sensitivity of 91.7%, specificity of 82.1%, PPV of 68.8%, and NPV of 95.8%. CD Activity in Capsule Endoscopy correlated well with LRG values (Spearman's rank correlation coefficient ρ = 0.681, P< 0.001). An LRG cutoff value of 14 μg/mL may be useful in predicting the presence of SB ulcers ≥ 0.5 cm, and an LRG cutoff value of 12 μg/mL may be useful in predicting the absence of SB inflammatory findings.

Local Assessment and Small Bowel Crohn’s Disease Severity Scoring using AI

We present a machine learning and computer vision approach for a localized, automated, and standardized scoring of Crohn's disease (CD) severity in the small bowel, overcoming the current limitations of manual measurements CT enterography (CTE) imaging and qualitative assessments, while also considering the complex anatomy and distribution of the disease. Two radiologists introduced a severity score and evaluated disease severity at 7.5mm intervals along the curved planar reconstruction of the distal and terminal ileum using 236 CTE scans. A hybrid model, combining deep-learning, 3-D CNN, and Random Forest model, was developed to classify disease severity at each mini-segment. Precision, sensitivity, weighted Cohen's score, and accuracy were evaluated on a 20% hold-out test set. The hybrid model achieved precision and sensitivity ranging from 42.4% to 84.1% for various severity categories (normal, mild, moderate, and severe) on the test set. The model's Cohen's score (κ=0.83) and accuracy (70.7%) were comparable to the inter-observer agreement between experienced radiologists (κ=0.87, accuracy = 76.3%). The model accurately predicted disease length, correlated with radiologist-reported disease length (r=0.83), and accurately identified the portion of total ileum containing moderate-to-severe disease with an accuracy of 91.51%. The proposed automated hybrid model offers a standardized, reproducible, and quantitative local assessment of small bowel CD severity and demonstrates its value in CD severity assessment.

Artificial Intelligence for Quantifying Cumulative Small Bowel Disease Severity on CT-Enterography in Crohn's Disease.

Assessing the cumulative degree of bowel injury in ileal Crohn's disease (CD) is difficult. We aimed to develop machine learning (ML) methodologies for automated estimation of cumulative ileal injury on computed tomography-enterography (CTE) to help predict future bowel surgery. Adults with ileal CD using biologic therapy at a tertiary care center underwent ML analysis of CTE scans. Two fellowship-trained radiologists graded bowel injury severity at granular spatial increments along the ileum (1 cm), called mini-segments. ML segmentation methods were trained on radiologist grading with predicted severity and then spatially mapped to the ileum. Cumulative injury was calculated as the sum (S-CIDSS) and mean of severity grades along the ileum. Multivariate models of future small bowel resection were compared with cumulative ileum injury metrics and traditional bowel measures, adjusting for laboratory values, medications, and prior surgery at the time of CTE. In 229 CTE scans, 8,424 mini-segments underwent analysis. Agreement between ML and radiologists injury grading was strong (κ = 0.80, 95% confidence interval 0.79-0.81) and similar to inter-radiologist agreement (κ = 0.87, 95% confidence interval 0.85-0.88). S-CIDSS (46.6 vs 30.4, P = 0.0007) and mean cumulative injury grade scores (1.80 vs 1.42, P < 0.0001) were greater in CD biologic users that went to future surgery. Models using cumulative spatial metrics (area under the curve = 0.76) outperformed models using conventional bowel measures, laboratory values, and medical history (area under the curve = 0.62) for predicting future surgery in biologic users. Automated cumulative ileal injury scores show promise for improving prediction of outcomes in small bowel CD. Beyond replicating expert judgment, spatial enterography analysis can augment the personalization of bowel assessment in CD.

Risk factors for surgery in stricturing small bowel Crohn's disease: A retrospective cohort study from the GETAID pédiatrique.

Previous studies have shown rates of surgical resection of up to 41% in stricturing pediatric Crohn's disease (CD). In this retrospective multicenter study, our aims were to identify clinical risk factors and magnetic resonance enterography (MRE) features of small bowel strictures associated with surgery. Pediatric patients with symptomatic stricturing small bowel CD (defined as obstructive symptoms or proximal dilatation on MRE) confirmed by MRE between 2010 and 2020 were recruited from 12 French tertiary hospitals. Patient characteristics were compared by surgical outcome multivariable Cox regression. Fifty-six patients (61% boys) aged 12.2 ± 2.7 years at diagnosis of CD were included. Median duration of CD before diagnosis of stricture was11.7 months (interquartile range [IQR]: 25-75: 1.2-29.9). Nineteen (34%) patients had stricturing phenotype (B2) at baseline. Treatments received before stricture diagnosis includedMODULEN-IBD (n = 31), corticosteroids (n = 35), antibiotics (n = 10), anti-TNF (n = 27), immunosuppressants (n = 28). Thirty-six patients (64%) required surgery, within 4.8 months (IQR: 25-75: 1.8-17.3) after stricture diagnosis. Parameters associated with surgical resection wereantibiotic exposure before stricture diagnosis (adjusted odds ratio [aOR]: 15.62 [3.35-72.73], p = 0.0005), Crohn's disease obstructive symptoms score (CDOS) > 4 (aOR: 3.04 [1.15-8.03], p = 0.02) and dilation proximal to stricture >28 mm (aOR: 3.62 [1.17-11.20], p = 0.03). In this study, antibiotic treatment before stricture diagnosis, intensity of obstructive symptoms, and diameter of dilation proximal to small bowel stricture on MRE were associated with risk for surgical resection.

Surgical management of duodenal crohn's disease.

Operative options for duodenal Crohn's disease include bypass, stricturoplasty, or resection. What factors are associated with operation selection and whether differences exist in outcomes is unknown. Patients with duodenal Crohn's disease requiring operative intervention across a multi-state health system were identified. Patient and operative characteristics, short-term surgical outcomes, and the need for future endoscopic or surgical management of duodenal Crohn's disease were analyzed. 40 patients underwent bypass (n = 26), stricturoplasty (n = 8), or resection (n = 6). Median age of diagnosis of Crohn's disease was 23.5years, and over half of the patients had undergone prior surgery for CD. Operation type varied by the most proximal extent of duodenal involvement. Patients with proximal duodenal CD underwent bypass operations more commonly than those with mid- or distal duodenal disease (p = 0.03). Patients who underwent duodenal stricturoplasty more often required concomitant operations for other sites of small bowel or colonic CD (63%) compared to those who underwent bypass (39%) or resection (33%). No patients required subsequent surgery for duodenal CD at a median follow-up of 2.8years, but two patients required endoscopic dilation (n = 1 after stricturoplasty, n = 1 after resection). Patients who require surgery for duodenal Crohn's disease appear to have an aggressive Crohn's disease phenotype, represented by a younger age of diagnosis and a high rate of prior resection for Crohn's disease. Choice of operation varied by proximal extent of duodenal Crohn's disease.