Small Bowel Healing Detected by Endoscopy in Patients With Crohn's Disease After Treatment With Antibodies Against Tumor Necrosis Factor

One-year Safety and Effectiveness of Ustekinumab in Patients With Crohn's Disease: The K-STAR Study

BACKGROUND

This study investigated the safety and effectiveness of ustekinumab (UST) in Korean patients with Crohn's disease (CD).

METHODS

Adult patients with CD treated with UST were prospectively enrolled in the K-STAR (Post-MarKeting Surveillance for Crohn's Disease patients treated with STelARa) study between April 2018 and April 2022. Both the clinical effectiveness and adverse effects of UST therapy were analyzed. Missing data were handled using nonresponder imputation (ClinicalTrials.gov Identifier: NCT03942120).

RESULTS

Of the 464 patients enrolled from 44 hospitals across Korea, 457 and 428 patients (Crohn's disease activity index ≥150) were included in the safety analysis and effectiveness analysis sets, respectively. At weeks 16 to 20 after initiating UST, clinical response, clinical remission, and corticosteroid-free remission rates were 75.0% (321 of 428), 64.0% (274 of 428), and 61.9% (265 of 428), respectively. At week 52 to 66, clinical response, clinical remission, and corticosteroid-free remission rates were 62.4% (267 of 428), 52.6% (225 of 428), and 50.0% (214 of 428), respectively. Combined effectiveness (clinical response + biochemical response) was achieved in 40.0% (171 of 428) and 41.6% (178 of 428) at week 16 to 20 and week 52 to 66, respectively. Biologic-naïve patients exhibited significantly higher rates of combined effectiveness than biologic-experienced patients (50.3% vs 30.7% at week 16-20, P < .001; 47.7% vs 36.0% at week 52-66, P = .014). No additional benefits were observed with the concomitant use of immunomodulators. Ileal location was independently associated with a higher probability of clinical remission compared with colonic or ileocolonic location at week 52 to 66. Adverse and serious adverse events were observed in 28.2% (129 of 457) and 12.7% (58 of 457), respectively, with no new safety signal associated with UST treatment.

CONCLUSIONS

Ustekinumab was well-tolerated, effective, and safe as induction and maintenance therapy for CD in Korea.

Guidelines for endoscopic diagnosis and treatment of inflammatory bowel diseases

In recent years, we have seen a considerable increase in the number of patients with inflammatory bowel diseases of unknown etiology, including both Crohn's disease and ulcerative colitis. Inflammatory bowel diseases can cause intestinal lesions throughout the gastrointestinal tract, necessitating gastrointestinal endoscopy for examining all relevant aspects, especially lesion characteristics, for differential diagnosis and histological diagnosis, to select the appropriate treatment options, determine treatment effectiveness, etc. Specific guidelines are necessary to ensure that endoscopy can be performed in a safe and more tailored and efficient manner, especially since gastrointestinal endoscopy, including enteroscopy, is a common procedure worldwide, including in Japan. Within this context, the Japan Gastroenterological Endoscopy Society has formulated the "Guidelines for the Endoscopic Diagnosis and Treatment of Inflammatory Bowel Diseases" to provide detailed guidelines regarding esophagogastroduodenoscopy, enteroscopy, and colonoscopy procedures for definitive diagnosis, as well as determination of treatment effectiveness in clinical cases of inflammatory bowel diseases.

Effectiveness of biologics for endoscopic healing in patients with isolated proximal small bowel Crohn's disease

BACKGROUND

Endoscopic healing (EH) is a key therapeutic target in Crohn's disease (CD). Proximal small bowel (SB) lesions in patients with CD are associated with a significant risk of strictures and bowel resection. Assessing SB in patients with CD is necessary because of its significant therapeutic implications. The advent of biologic therapies, including infliximab, ustekinumab, and vedolizumab, has significantly altered CD treatment. However, data on the efficacy of biologics in achieving EH, specifically in the proximal SB of patients with CD, remain limited.

AIM

To assess the effectiveness of biologics for EH in patients with jejunal and/or proximal ileal CD.

METHODS

Between 2017 and 2023, we retrospectively included 110 consecutive patients with isolated proximal SB CD, identified through baseline balloon-assisted enteroscopy. These patients completed 1-year of treatment with infliximab, ustekinumab, or vedolizumab, and underwent a second balloon-assisted enteroscopy at 1 year. Complete EH was defined as a modified Simple Endoscopic Score for CD (SES-CD) of < 3, while EH of the jejunum and proximal ileum was defined as a segmental modified SES-CD of 0.

RESULTS

In total, 64 patients were treated with infliximab, 28 with ustekinumab, and 18 with vedolizumab. The complete EH rate at 1 year was 20.9% (23/110), with 29.6% (19/64) for infliximab, 10.7% (3/28) for ustekinumab, and 5.5% (1/18) for vedolizumab. The median modified SES-CD significantly decreased compared to baseline [5 (2-8) vs 8 (6-9), P < 0.001]. The jejunal and proximal ileal EH rates at 1 year were 30.8% (12/39) and 15.5% (16/103), respectively. Multiple logistic regression analysis showed that stricturing or penetrating disease [odds ratio (OR) = 0.261, 95%CI: 0.087-0.778, P = 0.016], prior exposure to biologics (OR = 0.080, 95%CI: 0.010-0.674, P = 0.020), and moderate-to-severe endoscopic disease (OR = 0.277, 95%CI: 0.093-0.829, P = 0.022) were associated with a lower likelihood of achieving EH at 1 year.

CONCLUSION

Only 20.9% of patients with isolated proximal SB CD achieved complete EH after 1 year of biologic therapy.

Leucine-rich alpha-2 glycoprotein as a superior biomarker to C-reactive protein for detecting small bowel lesions in Crohn's disease

BACKGROUND

Achievement of endoscopic healing (EH) is significant in the clinical practice of inflammatory bowel disease as it is correlated with improved prognosis. Existing biomarkers, including C-reactive protein (CRP), have relatively low accuracy for predicting EH, especially in small intestinal lesions in Crohn's disease (CD); thus, noninvasive and more accurate biomarkers are required. Leucine-rich alpha-2 glycoprotein (LRG), a 50-kD protein, is produced under inflammatory conditions and has been reported to be useful in assessing disease activity in inflammatory bowel disease. However, the usefulness of LRG in small intestinal lesions in CD remains inconclusive.

AIM

To determine the usefulness of LRG for EH in small bowel lesions in CD and compare it with CRP.

METHODS

This study included 133 consecutive patients with CD who underwent balloon-assisted enteroscopy between June 2021 and March 2024 at Shiga University of Medical Science Hospital (Otsu, Japan). We retrospectively analyzed endoscopic scores in each of the ileum and colon and four markers including LRG, CRP, albumin, and Harvey-Bradshaw index (HBI). Spearman's rank correlation coefficient and receiver operating characteristic analysis were performed.

RESULTS

Either active ileal or colonic lesions exhibited significant differences in LRG, CRP, albumin, and HBI compared with EH. CRP, albumin, and HBI showed a worse correlation with endoscopic activity in the ileum than that in the colon; however, LRG did not show a worse correlation (colon, r = 0.5218; ileum, r = 0.5602). Receiver operating characteristic analysis revealed that LRG for EH in the ileum and colon had the same cutoff values of 12.4 μg/mL. Comparing the areas under the curve of LRG and CRP for predicting EH in the ileum revealed a significantly higher areas under the curve of LRG (95% confidence interval, 0.017-0.194; P = 0.024), whereas the two showed no significant difference in the colon.

CONCLUSION

LRG is a useful biomarker in assessing the endoscopic activity of CD and is more useful than CRP in the small intestine.

Computed tomography enterography-based radiomics for assessing mucosal healing in patients with small bowel Crohn's disease

BACKGROUND

Mucosal healing (MH) is the major therapeutic target for Crohn's disease (CD). As the most commonly involved intestinal segment, small bowel (SB) assessment is crucial for CD patients. Yet, it poses a significant challenge due to its limited accessibility through conventional endoscopic methods.

AIM

To establish a noninvasive radiomic model based on computed tomography enterography (CTE) for MH assessment in SBCD patients.

METHODS

Seventy-three patients diagnosed with SBCD were included and divided into a training cohort (n = 55) and a test cohort (n = 18). Radiomic features were obtained from CTE images to establish a radiomic model. Patient demographics were analysed to establish a clinical model. A radiomic-clinical nomogram was constructed by combining significant clinical and radiomic features. The diagnostic efficacy and clinical benefit were evaluated via receiver operating characteristic (ROC) curve analysis and decision curve analysis (DCA), respectively.

RESULTS

Of the 73 patients enrolled, 25 patients achieved MH. The radiomic-clinical nomogram had an area under the ROC curve of 0.961 (95% confidence interval: 0.886-1.000) in the training cohort and 0.958 (0.877-1.000) in the test cohort and provided superior clinical benefit to either the clinical or radiomic models alone, as demonstrated by DCA.

CONCLUSION

These results indicate that the CTE-based radiomic-clinical nomogram is a promising imaging biomarker for MH and serves as a potential noninvasive alternative to enteroscopy for MH assessment in SBCD patients.

Improvement of Transmural Inflammation With Adalimumab Versus Immunomodulator Maintenance Therapy in Pediatric Crohn's Disease: Single-Center Prospective Evaluation Using the Pediatric Inflammatory Crohn's Magnetic Resonance Enterography Index

BACKGROUND AND AIMS

Transmural healing, including as assessed by magnetic resonance enterography (MRE) has been associated with long-term favorable outcomes in Crohn's Disease (CD), but data concerning MRE improvement and normalization with therapy are sparse. We performed a prospective longitudinal study utilizing the recently developed pediatric MRE-based multi-item measure of inflammation (PICMI) to examine the efficacy of adalimumab (ADA) and immunomodulator (IM) in attaining improvement of transmural inflammation of the small intestine.

METHODS

Pediatric patients with CD involving small bowel and initiating ADA or IM were prospectively enrolled and followed with repeat MRE at 1 year. A single radiologist provided global assessment (RGA) and scored PICMI items (wall thickness, wall diffusion restriction, mural ulcers, comb sign, mesenteric edema) blinded to clinical information and to the timing of MRE. The primary outcome was mild improvement in PICMI at one year without a change in therapy.

RESULTS

Sixty-two eligible patients were enrolled, 26 receiving ADA and 36 IM. On intent to treat basis, a decline in PICMI score of >20 points without change of therapy was observed more frequently in ADA versus IM-treated patients (54% vs 31%, P = .01). By RGA, 71% improved with ADA vs 42% with IM (P = .03). MRE normalization was rare with both treatments (9% vs 6%, P = .62). A change in PICMI of >20 points was confirmed as the best cut off for MRE improvement as assessed by RGA also for the small bowel.

CONCLUSIONS

ADA therapy was associated with objective improvement in MRE findings of inflammation more frequently than IM. The low rate of MRE normalization suggests that this is not yet a realistic target with existing therapies.

Inadequate Efficacy of Biologics for Treating Proximal Ileal Lesions in Crohn's Disease; A Prospective Multicenter Study

BACKGROUND & AIMS

Although biologic therapy has revolutionized the treatment of Crohn's disease (CD), surgery remains unavoidable in cases involving ileal complications. We aimed to evaluate the efficacy of biologics on proximal ileal lesions using balloon-assisted enteroscopy (BAE).

METHODS

This open-label multicenter prospective study was conducted at tertiary referral centers in Japan. We enrolled 253 patients with active ileal CD who were treated with biologics (infliximab/adalimumab/ustekinumab/vedolizumab). BAE was performed at week 0 and week 26, and endoscopic findings were centrally assessed. We evaluated the rate of endoscopic remission (defined as having a maximum modified Simple Endoscopic Score for Crohn's disease <4) at week 26 and patient prognosis (CD-related hospitalization and surgery).

RESULTS

At baseline, 74 patients (29.2%) had proximal ileal ulcerations without terminal ileal ulcerations. The second BAE showed that endoscopic remission was achieved in 91 patients (36.0%). Of the patients with complete ulcer healing of the terminal ileum, 28.6% (22/77) had residual ulcers in the proximal ileum. The rate of endoscopic remission in the proximal ileum (50.9%) was relatively lower compared with the colon (63.4%) and terminal ileum (56.7%), a trend consistently observed across all treatment agents. After a median follow-up of 134 weeks, residual ulcerations in the proximal ileum were associated with a poorer prognosis (P = .0126 for hospitalization and P = .0014 for surgery).

CONCLUSIONS

A substantial proportion of patients with CD exhibited ulcerations in the proximal ileum, which correlated with a poorer prognosis. These lesions proved challenging to heal, regardless of the type of biologic used.

Optimization of transplantation methods using isolated mesenchymal stem/stromal cells: clinical trials of inflammatory bowel diseases as an example

Mesenchymal stem/stromal cells (MSCs) are distributed in various tissues and are used in clinical applications as a source of transplanted cells because of their easy harvestability. Although MSCs express numerous cell-surface antigens, single-cell analyses have revealed a highly heterogeneous cell population depending on the original tissue and donor conditions, including age and interindividual differences. This heterogeneity leads to differences in their functions, such as multipotency and immunomodulatory effects, making it challenging to effectively treat targeted diseases. The therapeutic efficacy of MSCs is controversial and depends on the implantation site. Thus, there is no established recipe for the transplantation of MSCs (including the type of disease, type of origin, method of cell culture, form of transplanted cells, and site of delivery). Our recent preclinical study identified appropriate MSCs and their suitable transplantation routes in a mouse model of inflammatory bowel disease (IBD). Three-dimensional (3D) cultures of MSCs have been demonstrated to enhance their properties and sustain engraftment at the lesion site. In this note, we explore the methods of MSC transplantation for treating IBDs, especially Crohn's disease, from clinical trials published over the past decade. Given the functional changes in MSCs in 3D culture, we also investigate the clinical trials using 3D constructs of MSCs and explore suitable diseases that might benefit from this approach. Furthermore, we discuss the advantages of the prospective isolation of MSCs in terms of interindividual variability. This note highlights the need to define the method of MSC transplantation, including interindividual variability, the culture period, and the transplantation route.

Real-world evidence of combined treatment of biologics and exclusive enteral nutrition in patients with ileum-dominant Crohn's disease: A multicenter study

BACKGROUND & AIMS

Although biologics were prescribed to achieve and maintain clinical remission of active Crohn's disease (CD), almost half of patients experienced a loss of response or intolerance. Here, we investigated the efficacy of combined treatment of biologics and 16-weeks exclusive enteral nutrition (EEN) in moderate-to-severe CD patients with small intestine lesions.

METHODS

This was a real-world, multicenter retrospective study, from October 2016 to March 2023, medical records of patients registered at three IBD centers were reviewed for patients with ileal or ileocolonic CD in moderate-to-severe activity. All patients received treatment of biologics with concomitant 16-week EEN (BioEEN) or biologics alone (Bio). The clinical outcomes and endoscopic outcomes were assessed at week 16 and 52.

RESULTS

There was no statistically significant difference between Bio (97 patients) and BioEEN group (100 patients) at baseline for demographic and clinical characteristics. Compared to treatment with biologics alone, patients with BioEEN treatment achieved higher rates of clinical response (95.0% vs. 66.0%), clinical remission (87.0% vs. 52.6%), endoscopic response (91.4% vs. 47.4%) including mucosal healing (85.7% vs. 23.7%) at week 16. The superiority of BioEEN sustained in maintenance, with 84.7% (vs. 49.1%) clinical response, 77.8% (vs. 38.6%) clinical remission, 69.2% (vs. 32.6%) endoscopic response and 51.9% (vs. 18.6%) mucosal healing at week 52.

CONCLUSIONS

Combined treatment of biologics and 16-week EEN was an efficient therapeutic strategy with affirmative effectiveness for small intestine diseases of active CD.

Ustekinumab effectiveness in Crohn's disease with lesions in the intestines

Ustekinumab is prescribed for the treatment of patients with steroid-resistant moderate to severe Crohn's disease. We investigated its clinical outcome in patients with small and large intestinal lesions. Patients who were newly administered ustekinumab between March 2014 and December 2020 at Hamamatsu University Hospital were included in the study. The primary endpoint was Crohn's disease activity index score at baseline and weeks 8, 24, and 48 after the initiation of treatment, and secondary endpoints were albumin, hemoglobin, and C-reactive protein at these time points. Ustekinumab treatment retention was examined in both groups; the 2 groups were compared using the Friedman test, Mann-Whitney U test, or Fisher exact test. Overall, Crohn's disease activity index scores improved between baseline and 48 weeks, but the difference was not significant. However, there was a significant improvement between baseline and 48 weeks in patients with lesions in the small intestine only. Overall, patients showed significant improvement in albumin levels between baseline and 48 weeks but not in C-reactive protein or hemoglobin levels. When limited to patients with lesions in the small intestine, albumin and hemoglobin levels showed significant improvement. Both types showed high rates of treatment retention, although there was no significant difference. Ustekinumab appears to be a safe and effective treatment option that may be particularly effective in patients with lesions in the small intestine only.

Comparing the Effects of Anti-TNF Agent and Ustekinumab on Small Bowel Inflammation in Crohn's Disease: Inverse Probability Weighting With Stabilized Weights of Propensity Scores

Background

Endoscopic mucosal healing serves as a critical predictor for achieving long-term remission in Crohn's disease treatment. Recent data indicate that the effectiveness of healing varies based on the location of gastrointestinal inflammation. Additionally, reports suggest that antitumor necrosis factor-α (anti-TNF-α) agents exhibit reduced efficacy in treating small intestinal inflammation compared to colorectal inflammation. Conversely, limited research exists regarding the impact of the anti-IL12/23 agent ustekinumab (UST) on small intestinal inflammation. This study aimed to compare the effects of anti-TNF-α agents and UST on small intestinal inflammation using propensity score analysis.

Methods

This retrospective observational study involved 70 patients with Crohn's disease who had inflammation in the small intestine and had initiated treatment with either anti-TNF agents or UST between March 2015 and August 2021. Endoscopic findings were evaluated before treatment commencement and at 1-2 years post-treatment initiation. The propensity score was employed to compare the efficacy of TNF agents and UST on small bowel inflammation.

Results

Ustekinumab exhibited greater improvement in the small intestinal endoscopy score than anti-TNF-α antibodies according to the propensity score analysis (inverse probability weighting; P = .0448). However, no significant disparity was observed in the overall improvement of endoscopic scores between UST and anti-TNF-α antibodies (P = .5938).

Conclusions

This study suggests that UST might be more effective than anti-TNF-α agents in treating small intestinal inflammation in Crohn's disease.

Efficacy of exclusive enteral nutrition on the mucosal healing of different gastrointestinal segments in children with Crohn's disease

OBJECTIVE

To investigate the association between disease location and segmental mucosal healing (SMH) following exclusive enteral nutrition (EEN) in children with Crohn's disease (CD).

METHODS

Treatment-naive pediatric patients with endoscopically active CD treated with EEN alone as induction therapy were retrospectively enrolled from January 1, 2017 to June 30, 2022. The simple endoscopic score for CD (SES-CD) was employed to score disease activity in the upper gastrointestinal (GI) tract (esophagus, stomach, duodenum), rectum, left colon, transverse colon, right colon, and terminal ileum. While the Lewis score assessed that of the small bowel from the jejunum to the proximal ileum (except the terminal ileum). The variation in the total scores for each segment and SES-CD subscores for each ileocolonic segment from baseline to 1 year after EEN therapy and the segmental endoscopic outcomes and potential predictors associated with SMH for the segments scored by SES-CD were evaluated.

RESULTS

Overall, 82 children with CD were enrolled. Except for the upper GI segment, scores in other segments declined significantly from baseline to EEN completion (all P < 0.001). We analyzed 486 segments (79, 80, 81, 82, 82 and 82 from upper GI tract, terminal ileum, right colon, transverse colon, left colon, and rectum) and found that the segmental SES-CD at baseline (odds ratio [OR] 0.62, 95% confidence interval [CI] 0.55-0.70, P < 0.001) and upper GI location (OR 0.25, 95% CI 0.11-0.55, P = 0.001) were associated with SMH at EEN completion.

CONCLUSION

Disease location of the upper GI segment in pediatric CD was associated with SMH following EEN therapy.

Use of double-balloon endoscopy and an endoscopic scoring system to assess endoscopic remission in isolated small bowel Crohn's disease after treatment with infliximab

Background

It is unclear how clinical and endoscopic factors affect the attainment of endoscopic remission (ER) in patients with small bowel Crohn's disease (SB-CD) who are infliximab-naïve.

Objectives

We aimed to identify the effect of different factors on attaining ER using double-balloon endoscopy (DBE) evaluation.

Design

A single-center retrospective observational study was conducted from 1 January 2018 to 30 November 2022. Among 262 patients who were screened for isolated SB-CD by baseline DBE, 108 patients were assessed for effectiveness during maintenance infliximab therapy by a second DBE evaluation.

Methods

DBE findings before and after infliximab therapy were compared. ER was defined as a simple endoscopic score for CD (SES-CD) below 3, and segmental ER as SES-CD activity of 0. Multivariate regression with calculations of odds ratios (OR) was used to determine the impact of different factors on attaining ER.

Results

In all, 41 patients (38.0%) achieved ER. An elevated C-reactive protein at week 6 was independently associated with a decreased probability of ER [OR: 0.86, 95% confidence interval (CI) = 0.75-0.98, p = 0.03]. Segmental ER of the terminal ileum, rather than the proximal ileum, was associated with a higher rate of ER (60.9% versus 38.2%, p = 0.01). High baseline SES-CD (⩾16) was unrelated to overall ER. For patients with disease in the terminal ileum, those with moderate/severe disease were less likely to attain segmental ER than those with mild disease [adjusted odds ratios (aOR): 0.27, 95% CI: 0.09-0.83, p = 0.02]. A large ulcer in the terminal ileum was associated with a lower rate of segmental ER (aOR: 0.18, 95% CI: 0.06-0.56, p = 0.01).

Conclusion

For infliximab-naïve patients with SB-CD, the overall severity of the endoscopic score was unrelated to attainment of ER. Patients were less likely to attain segmental ER if they had greater endoscopic inflammation or larger ulcers in the terminal ileum.

Comparison of an Endoscopic Scoring System and the Simplified Magnetic Resonance Index of Activity in Patients with Small Bowel Crohn's Disease

Background/Aims

The newly derived simplified magnetic resonance index of activity (MARIAs) has not been verified in comparison to balloon-assisted enteroscopy (BAE) for patients with small bowel Crohn's disease (CD). We studied the correlation of MARIAs with simple endoscopic scores for CD (SES-CD) of the ileum based on magnetic resonance enterography (MRE) and BAE in patients with small bowel CD.

Methods

Fifty patients with small bowel CD who underwent BAE and MRE concurrently within 3 months from September 2020 to June 2021 were enrolled in the study. The primary outcome was the correlation between the active score of ileal SES-CD (ileal SES-CDa)/ileal SES-CD and MARIAs based on BAE and MRE. The cutoff value for MARIAs identifying endoscopically active/severe disease, defined as ileal SES-CDa/ileal SES-CD of 5/7 or more, was analyzed.

Results

Ileal SES-CDa/ileal SES-CD and MARIAs showed strong associations (R=0.76, p<0.001; R=0.78, p<0.001). The area under the receiver operating characteristic curve of MARIAs for ileal SES-CDa ≥5 and ileal SES-CD ≥7 was 0.92 (95% confidence interval, 0.88 to 0.97) and 0.92 (95% confidence interval, 0.87 to 0.97). The cutoff value of MARIAs for detecting active/severe disease was 3. A MARIAs index value of ≥3 identified ileal SES-CDa ≥5 with a sensitivity of 85% and specificity of 87% and detected ileal SES-CD ≥7 with a sensitivity of 87% and specificity of 86%.

Conclusions

This study validated the applicability of MARIAs compared to BAE-based ileal SES-CDa/SES-CD.

Combination of leucine-rich alpha-2 glycoprotein and fecal markers detect Crohn's disease activity confirmed by balloon-assisted enteroscopy

BACKGROUND/AIMS

Endoscopic activity confirmed by enteroscopy is associated with poor clinical outcome in Crohn's disease (CD). We investigated which of the existing biomarkers best reflects endoscopic activity in CD patients including the small bowel, and whether their combined use can improve accuracy.

METHODS

One hundred and four consecutive patients with ileal and ileocolonic type CD who underwent balloon-assisted enteroscopy (BAE) from October 2021 to August 2022 were enrolled, with clinical and laboratory data prospectively collected and analyzed.

RESULTS

Hemoglobin, platelet count, C-reactive protein, leucine-rich alpha-2 glycoprotein (LRG), fecal calprotectin, and fecal hemoglobin all showed significant difference in those with ulcers found on BAE. LRG and fecal calprotectin showed the highest areas under the curve (0.841 and 0.853) for detecting ulcers. LRG showed a sensitivity of 78% and specificity of 80% at a cutoff value of 13 μg/mL, whereas fecal calprotectin showed a sensitivity of 91% and specificity of 67% at a cutoff value of 151 μg/g. Dual positivity for LRG and fecal calprotectin, as well as LRG and fecal hemoglobin, both predicted ulcers with an improved specificity of 92% and 100%. A positive LRG or fecal calprotectin/hemoglobin showed an improved sensitivity of 96% and 91%. Positivity for LRG and either of the fecal biomarkers was associated with increased risk of hospitalization, surgery, and relapse.

CONCLUSIONS

The biomarkers LRG, fecal calprotectin, and fecal hemoglobin can serve as noninvasive and accurate tools for assessing activity in CD patients confirmed by BAE, especially when used in combination.

Can balloon-assisted enteroscopy predict disease outcomes in patients with small-bowel Crohn's disease?

There are limited studies on the endoscopic assessment of disease activity using balloon-assisted enteroscopy (BAE) and its predictive role for long-term outcomes of patients with small bowel Crohn's disease (CD). We sought to investigate the value of BAE as a predictor of long-term outcomes in patients with small-bowel CD. A total of 111 patients with small-bowel CD whose endoscopic disease activity was assessed using BAE based on the small-bowel simple endoscopic score for Crohn's disease (small-bowel SES-CD) at Samsung Medical Center were retrospectively selected from January 2014 to August 2020. The outcome was an evaluation of the risk of surgery according to a small-bowel SES-CD of 0-6 vs. ≥ 7 and endoscopic findings (presence of any ulcer and degree of stricture) using the Cox proportional hazards model. The risk of surgery was significantly increased in patients with a small-bowel SES-CD of ≥ 7 compared to a small-bowel SES-CD of 0-6 [hazard ratio (HR) 6.31; 95% confidence interval (CI) 1.48-26.91; p = 0.013]. In addition, the risk of surgery was significantly increased in patients with stenosis with "cannot be passed" compared to the cases without stenosis (HR 12.34; 95% CI 1.66-91.92; p = 0.014), whereas there was no significance in any ulcer. The present study demonstrated the role of BAE in the endoscopic assessment of disease activity and its predictive value for the risk of surgery in small-bowel CD patients. Further optimization of BAE utilization for the assessment of disease activity is warranted in clinical practice.

Serum Leucine-Rich α2 Glycoprotein: A Novel Biomarker for Transmural Inflammation in Crohn's Disease

INTRODUCTION

Leucine-rich alpha-2 glycoprotein (LRG) is a newly studied biomarker for inflammatory diseases. This study aimed to investigate whether LRG can be used for evaluating transmural activity in patients with Crohn's disease (CD).

METHODS

We performed magnetic resonance enterography (MRE) in 227 consecutive CD patients from June 2020 to August 2021. We prospectively compared MRE findings with clinical and laboratory data including LRG. MRE was evaluated using 2 validated scoring systems, and transmural inflammation was defined as having a maximum simplified magnetic resonance index of activity (sMaRIA) score of ≥4 and a 5-point classification score of ≥9, respectively.

RESULTS

The correlation between LRG and the total MRE score showed a positive correlation ( r = 0.576 for sMaRIA score, P < 0.01 and r = 0.633 for 5-point score, P < 0.01). Serum concentrations of LRG significantly increased as MRE scores increased ( P < 0.01). The area under the curve of LRG for sMaRIA score of ≥4 and 5-point score of ≥9 was 0.845 and 0.869, respectively, which was significantly higher than that of CDAI ( P < 0.01) or C-reactive protein ( P < 0.01). LRG levels of ≥14 μg/mL had a 67% sensitivity and a 90% specificity for sMaRIA score of ≥4, and 73% sensitivity and 89% specificity for 5-point score of ≥9. Patients with high LRG levels were also strongly associated with CD-related hospitalization, surgery, and clinical relapse compared to those with low LRG levels ( P < 0.01 for all).

DISCUSSION

LRG is a highly accurate serum biomarker for detecting transmural activity in CD patients. Results need to be validated in further multicenter studies.

Systematic review of artificial intelligence-based image diagnosis for inflammatory bowel disease

OBJECTIVES

Diagnosis of inflammatory bowel diseases (IBD) involves combining clinical, laboratory, endoscopic, histologic, and radiographic data. Artificial intelligence (AI) is rapidly being developed in various fields of medicine, including IBD. Because a key part in the diagnosis of IBD involves evaluating imaging data, AI is expected to play an important role in this aspect in the coming decades. We conducted a systematic literature review to highlight the current advancement of AI in diagnosing IBD from imaging data.

METHODS

We performed an electronic PubMed search of the MEDLINE database for studies up to January 2022 involving IBD and AI. Studies using imaging data as input were included, and nonimaging data were excluded.

RESULTS

A total of 27 studies are reviewed, including 18 studies involving endoscopic images and nine studies involving other imaging data.

CONCLUSION

We highlight in this review the recent advancement of AI in diagnosing IBD from imaging data by summarizing the relevant studies, and discuss the future role of AI in clinical practice.

Comparative Effectiveness of Biologics for Endoscopic Healing of the Ileum and Colon in Crohn's Disease

INTRODUCTION

We compared the efficacy of adalimumab, infliximab, ustekinumab, and vedolizumab on the ability to achieve endoscopic healing (EH) after 1 year of therapy in moderate-severe Crohn's disease (CD).

METHODS

This was a pooled analysis of patient-level data from 299 patients with CD from 4 clinical trials. Proportions of patients treated with each biologic were compared for achieving 1-year complete EH (Simple Endoscopic Score for CD [SES-CD] <3) and ileal and colonic EH separately (SES-CD = 0). Multivariate logistic regression was used to model the relationship between biologics and 1-year outcomes and adjusted for disease duration, concomitant corticosteroid use, and prior antitumor necrosis factor failure.

RESULTS

Compared with vedolizumab (4/56 [7.1%]), adalimumab (17/61 [27.9%], adjusted odds ratio [OR]: 5.79, 95% confidence interval [CI]: 1.77-18.95, P = 0.004) and infliximab (39/141 [27.7%], aOR: 4.59, 95% CI: 1.48-14.22, P = 0.008) had superior rates of 1-year EH. No significant difference was observed between vedolizumab and ustekinumab. Similar results were observed among biologic-naive patients. Among patients with baseline ileal SES-CD ≥3, no significant differences were observed between biologics for 1-year ileal EH. However, for large (>0.5 cm) ileal ulcers, infliximab (20/49 [40.8%]) had superior rates of no ileal ulcers compared with vedolizumab (2/23 [8.7%], aOR: 5.39, 95% CI: 1.03-28.05, P = 0.045). No other differences were observed. For colonic disease, compared with ustekinumab (9/31 [29.0%]), adalimumab (30/48 [62.5%], aOR: 3.97, 95% CI: 1.45-10.90, P = 0.007) had superior rates of 1-year EH in the colon, with similar trends observed for infliximab (55/105 [52.4%], aOR: 2.08, 95% CI: 0.82-5.27, P = 0.121). No other differences were observed.

DISCUSSION

In this post hoc analysis, TNF-α antagonists were overall superior to vedolizumab and ustekinumab for achieving 1-year EH in moderate-severe CD patients.

Ileal and colonic Crohn'´s disease: Ddoes location makes a difference in therapy efficacy?

Within the IBD entity of Crohn's disease, there is currently no differentiation between ileal and colonic manifestation for recruitment of patients in clinical trials, well-powered analysis of study results or therapeutic decisions in daily clinical practice. However, there is accumulating evidence from epidemiological, genetic, microbial, immunological, and clinical characteristics that clearly indicate that ileal Crohn's disease represents a distinct disease entity, which differentiates itself from colonic Crohn's disease. This is also reflected by lower efficacy of targeted therapies in isolated ileal compared to colonic Crohn's disease. The distinct site-specific mechanisms that drive heightened non-response in ileal disease need to be analysed in-depth in the future, to enable optimized therapy in the individual Crohn's disease patient.

Higher concentrations of cytokine blockers are needed to obtain small bowel mucosal healing during maintenance therapy in Crohn's disease

BACKGROUND

Several studies have reported a positive correlation between serum drug concentrations and endoscopic remission in patients with Crohn's disease.

AIM

To examine the association between the concentrations of cytokine blockers (infliximab, adalimumab and ustekinumab) and endoscopic remission of small bowel lesions.

METHOD

This was a cross-sectional study conducted at a single tertiary referral centre. Patients with Crohn's disease who received maintenance cytokine blocker therapy were recruited from April 2018 to May 2020. We performed balloon-assisted enteroscopy and collected serum samples to measure drug concentrations. The primary endpoint was the relationship between the concentrations of cytokine blockers and endoscopic remission in the small bowel.

RESULTS

We enrolled 143 patients, 66, 44 and 33 of whom were receiving infliximab, adalimumab and ustekinumab, respectively. Enteroscopic findings showed that the rate of endoscopic remission of small bowel lesions was significantly lower than that of colonic lesions (P < 0.01). For each agent, the mean drug concentration in patients exhibiting endoscopic remission in the small bowel was higher than that observed in patients with endoscopic remission in the colon (but not in the small bowel) or with any active disease (either in the small bowel, colon or both). Patients with infliximab, adalimumab and ustekinumab concentrations >5, 14 and 4 µg/mL were nearly 5.3-, 9.4- and 14.7-times more likely to exhibit endoscopic remission of the small bowel, respectively.

CONCLUSIONS

Cytokine blocker treatment was less efficacious for small bowel inflammation than colonic inflammation. Higher serum concentrations were needed to achieve endoscopic remission of small bowel lesions.

Location is important: differentiation between ileal and colonic Crohn's disease

Crohn's disease can affect any part of the gastrointestinal tract; however, current European and national guidelines worldwide do not differentiate between small-intestinal and colonic Crohn's disease for medical treatment. Data from the past decade provide evidence that ileal Crohn's disease is distinct from colonic Crohn's disease in several intestinal layers. Remarkably, colonic Crohn's disease shows an overlap with regard to disease behaviour with ulcerative colitis, underlining the fact that there is more to inflammatory bowel disease than just Crohn's disease and ulcerative colitis, and that subtypes, possibly defined by location and shared pathophysiology, are also important. This Review provides a structured overview of the differentiation between ileal and colonic Crohn's disease using data in the context of epidemiology, genetics, macroscopic differences such as creeping fat and histological findings, as well as differences in regard to the intestinal barrier including gut microbiota, mucus layer, epithelial cells and infiltrating immune cell populations. We also discuss the translation of these basic findings to the clinic, emphasizing the important role of treatment decisions. Thus, this Review provides a conceptual outlook on a new mechanism-driven classification of Crohn's disease.

Endoscopic Evaluation and Therapeutic Considerations of Small Bowel Crohn’s Disease

Small bowel evaluation is warranted in all newly diagnosed cases of Crohn’s disease (CD) as small bowel is involved in two-thirds of CD patients at diagnosis and the involvement can be discontinuous. Endoscopic evaluation of the small bowel in suspected or established CD can be done by video capsule endoscopy (VCE), device assisted enteroscopy (DAE) (which includes single and double balloon enteroscopy, novel motorized spiral enteroscopy (NMSE) and balloon guided endoscopy (BGE)) and intra-operative enteroscopy (IOE). In suspected CD with a negative ileo-colonoscopy, VCE is the preferred initial diagnostic modality in the absence of obstructive symptoms or known stenosis. VCE should be preceded by cross-sectional imaging or patency capsule testing if obstruction is suspected given with high retention risk. In established cases, small bowel cross-sectional imaging (magnetic resonance or computed tomography enterography) is preferred over VCE as it can assess transmural and extra-luminal involvement. VCE is indicated subsequently if necessary to assess disease extent, unexplained symptoms (e.g., anemia, malnutrition) or mucosal healing. Pan-enteric capsule endoscopy (PCE) and the use of artificial intelligence are the recent developments with VCE. DAE with small bowel biopsy can provide definitive evidence of CD including the extent and severity. A final diagnosis of CD is based on the constellation of clinical, radiologic, histologic and endoscopic features. Newer technologies like NMSE and BGE can help with deeper and faster small bowel evaluation. DAE has also allowed endoscopic treatment of small bowel strictures, small bowel bleeding and retrieval of retained capsule or foreign bodies. Endoscopic balloon dilation (EBD), endoscopic electro-incision, strictureplasty and stenting have shown promising results in CD related small bowel strictures. In conclusion, endoscopic evaluation of the small bowel is rapidly evolving field that has a major role in diagnosis and management of small bowel CD and can alter treatment outcomes in properly selected patients.

Ustekinumab is effective against small bowel lesions in Crohn's disease: two case reports

We encountered two patients with Crohn's disease (CD) for whom induction of ustekinumab was effective for the management of small intestinal lesions with stenosis. The first symptomatic CD case was a 40-year-old female with longitudinal ulcers in the small bowel found at double-balloon endoscopy. She was in a biologic-naïve condition. Her symptoms improved immediately after ustekinumab induction. We confirmed the condition of intestinal mucosa by double-balloon endoscopy. Deep ulcers remained open at 24 weeks and were scarred at 72 weeks. The second case was a 50-year-old male who failed to respond to treatment with anti-TNFα agents. The lumen was narrow caused by circumferential ulcer, and an endoscope could not pass the site before induction. The circumferential ulcer had been healed by ustekinumab induction, and an endoscope passed through at 72 weeks. These two cases support the therapeutic efficacy of ustekinumab in alleviating small bowel lesions in CD patients.

Efficacy of infliximab treatment on the mucosal healing of different intestinal segments in patients with ileocolonic Crohn's disease

BACKGROUND

Mucosal healing (MH) is the key aim of the treat-to-target strategy for patients with Crohn's disease (CD). The efficacy of infliximab (IFX) on MH in different ileocolonic segments is unclear. The aim of this study was to investigate endoscopic MH in different ileocolonic segments in patients with CD who received IFX treatment.

METHODS

A retrospective, single-center study was performed in patients with active ileocolonic CD between January 2012 and December 2018. All patients underwent IFX treatment for at least 30 weeks. The MH of five ileocolonic segments was assessed by the Simple Endoscopic Score for CD (SES-CD) at baseline, 14/22 weeks and 30/38 weeks. The SES-CD values were analyzed by a mixed-effects model after the correction for confounding factors.

RESULTS

A total of 101 eligible patients were included. The baseline endoscopic severity was similar across segments. At 30/38 weeks, the greatest changes in the SES-CD ulcer size and ulcerated surface subscores were -94.29% and -94.32% both in the transverse colon (p < 0.0001), and the smallest changes were -67.88% and -69.67% both in the terminal ileum (p < 0.0001) compared with baseline. Stenosis mainly presented in the right colon (12/29, 41.38%). The change in the SES-CD stenosis subscore was -6.25% in the right colon at 30/38 weeks compared with -71.88% at 14/22 weeks (p = 0.0030). At 30/38 weeks, the transverse colon achieved the highest rate of complete MH (CMH) at 81.2%, and the lowest CMH rate occurred in the terminal ileum at 45.6%. Moreover, the degree of improvement in the rectum was negatively correlated with disease progression (p = 0.011).

CONCLUSIONS

Ileocolonic segments in CD presented different degrees of endoscopic MH during IFX treatment. The transverse colon showed the highest CMH rate, whereas the right colon with stenosis showed the poorest improvement. The differing propensities of ileocolonic segments may provide an individualized IFX treatment strategy.

The microbiome can predict mucosal healing in small intestine in patients with Crohn's disease

BACKGROUND

Mucosal healing is the main treatment goal for Crohn's disease. In this situation, some patients have difficulty with endoscopic evaluation of the entire small intestine. Crohn's disease is closely associated with the gut microbiota, but the relationship between the microbiome and disease activity in the small intestine remains unclear. We examined the association between the microbiome and endoscopic findings in the small intestine and determined whether the microbiome can predict mucosal healing.

METHODS

The patients with Crohn's disease who were scheduled for capsule or balloon-assisted endoscopy were included in this prospective study. Patients whose entire small intestine was evaluated were divided into two groups based on ulcerative findings. The microbiomes in the fecal samples were analyzed using 16S rRNA sequencing.

RESULTS

The 38 enrolled patients were divided into the ulcer group (24) and mucosal healing group (14). The ulcer group exhibited lower α diversity. Six genera, namely Faecalibacterium (P = 0.008), Lachnospira (P = 0.009), Paraprevotella (P = 0.01), Dialister (P = 0.012), Streptococcus (P = 0.025), and Clostridium (P = 0.028) were enriched in the mucosal healing group. A predictive score for mucosal healing was defined using these six genera. The area under the curve was 0.795 and the sensitivity and specificity for predicting mucosal healing were 0.643 and 0.917, respectively.

CONCLUSIONS

Fecal microbiome is corelated with disease activity in the entire small intestine in Crohn's disease patients. The predictive score proposed by microbiota characteristics was a potential biomarker for mucosal healing in the small intestine.

Clinical management for small bowel of Crohn's disease in the treat-to-target era: now is the time to optimize treatment based on the dominant lesion

A treat-to-target strategy, in which treatment is continuously adjusted according to the results of scheduled objective monitoring, is optimal for patients with Crohn's disease (CD) in the era of biologics. The small bowel is a common site of intractable CD, which may result from multiple strictures or expanding lesions. To improve the prognosis of patients with small bowel CD, lesions should be proactively monitored within the subclinical phase. Objective assessment of small bowel lesions is technically difficult, however, due to the relatively poor correlation between endoscopic activity and clinical symptoms or biomarker titers. The presence of proximal small bowel lesions and asymptomatic "Real Silent CD" must be considered. Endoscopy remains the gold standard to assess these lesions. In clinical practice, the advantages and disadvantages of each imaging modality and biomarker must be carefully weighed for appropriate application and reliable monitoring. The prevalence of small bowel lesions depends on the precision of the imaging modality used for detection. Clinical management should be based on the dominant location of the intestinal lesions rather than classical classification. Optimal strategies for detecting and treating small bowel lesions in patients with CD must be developed utilizing reliable, precise, and objective monitoring.

Objective evaluation for treat to target in Crohn's disease

BACKGROUND

Crohn's disease (CD) is a chronic and destructive bowel disease; continued disease activity can lead to penetrating complications. With the recent advent of effective medications, the importance of using a treat-to-target approach to guide therapy is becoming important.

METHODS

In this review, we reviewed the previous evidence for evaluating CD lesions.

RESULTS

We describe ileocolonoscopy's role in assessing disease activity, as well as recent progress in modalities, such as balloon-assisted endoscopy, capsule endoscopy, magnetic resonance enterography, computed tomography enterography, and ultrasonography. Advances in modalities have changed CD assessment, with small-bowel involvement becoming more important.

CONCLUSIONS

Proper optimization is necessary in clinical practice.