Characteristics and prognosis of isolated small-bowel Crohn's disease

Genetic Mutations and Small Bowel Ulcerating Disease: Role in Diagnosis?

PURPOSE OF REVIEW

This review examines the role of genetic variations in the pathogenesis of small bowel (SB) ulcers associated with Crohn's disease (CD), NSAID enteropathy, and Cryptogenic Multifocal Ulcerous Stenosing Enteritis (CMUSE)/Chronic Non-Specific Ulcers of the Small Intestine (CNSU), aiming to address current diagnostic challenges.

RECENT FINDINGS

Advances in molecular genetics have revealed significant genetic contributors to SB ulceration. In CD, the NOD2 gene on chromosome 16 and several additional risk variants identified through genome-wide association studies (GWAS)-with key insights from the International Inflammatory Bowel Disease Genetics Consortium-have enhanced our understanding of the pathobiology of the disease. In NSAID enteropathy, polymorphisms in CYP enzymes have been associated with altered drug metabolism and gastrointestinal complications. However, the genetic mechanisms underlying deep ulcers in NSAID enteropathy, as well as CMUSE/CNSU, remain poorly understood. Genetic insights are crucial for understanding SB ulcerative diseases. Future research should focus on identifying specific genetic determinants to improve diagnostic accuracy and therapeutic strategies.

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.

Elevated fecal calprotectin: Does capsule endoscopy have a role in the diagnostic algorithm?

INTRODUCTION

The purpose of this study was to examine the utility of small bowel capsule endoscopy (SBCE) in the diagnostic pathway of patients that had elevated fecal calprotectin (FC) and normal colonoscopy.

METHODS

Patients with elevated FC and normal colonoscopy that underwent SBCE in the last 4 years were included. Patients were divided into 3 groups: group 1: patients with isolated small bowel Crohn's disease (SBCD) on SBCE; group 2: patients with elevated FC but normal SBCE; and group 3: patients with isolated terminal ileitis.

RESULTS

The study included 320 patients (group 1: 254 patients, group 2: 50 patients, and group 3: 16 patients). The median age was 42.5 years (IQR 26) across the three groups and 52.4% of the patients had a new diagnosis of SBCD. In group 1, active disease was identified distally in 247 patients (77.2%), proximal involvement in 90 patients (28.1%), and extensive SBCD in 68 patients (21.3%). Magnetic resonance enterography (MRE) was carried out in 229 (90.1%) patients in group 1 and was negative in 42 patients with SBCD. The diagnostic yield of SBCE was higher than that of MRE (p < 0.0001). In group 2, the final diagnoses included Helicobacter pylori infection (n = 2), NSAID use (n = 3), celiac disease (n = 2), and microscopic colitis (n = 1). The final diagnoses in group 3 were idiopathic terminal ileitis (n = 11), inflammatory bowel disease (n = 3), and infective terminal ileitis (n = 2).

CONCLUSION

SBCE influences the patient pathway even when negative/normal. It is better at identifying early SBCD, when compared with MRE.

Long-term follow-up of children with Crohn's disease and small bowel mucosal lesions detected through video capsule endoscopy

OBJECTIVES

We report disease outcomes of pediatric Crohn's disease (CD) affecting the proximal small bowel (SB) and detected through video capsule endoscopy (VCE).

METHODS

We undertook a retrospective review of CD patients with VCE performed under age 18 between 2003 and 2017 and having received any biologics. We identified patients from our institutional registry.

RESULTS

Eligible patients (n = 118) had their first VCE performed after a median of 0.1 years after diagnostic endoscopies at a median age of 12.2 years. The proximal SB disease group (Paris classification L4b inclusive) comprised 70 patients with extensive SB lesions in 81% and deep ulcers in 79%. Patients with Paris L1-3 disease with no findings in VCE or disease restricted to the terminal ileum comprised the control group. At first VCE, levels of albumin (34 vs. 37 g/L) and hemoglobin (117 vs. 127 g/L) were lower in SB patients (p < 0.02). After the first VCE, 68% were introduced to biologics, while 10% already received them. Follow-up VCE was performed after a median of 2.4 years (SB group n = 42; controls n = 21). Proximal SB findings had disappeared in 40% of SB patients, and extensive lesions and deep ulcers had decreased to 26% and 29%, respectively (p = 0.001). In the control group, one had progressed to proximal disease. During the clinical follow-up of a median of 4.7 years, one patient with SB underwent surgery for a jejunal stricture.

CONCLUSIONS

Proximal SB disease detected through capsule endoscopy abated in most patients with biological medication.

The utility of capsule endoscopy in the phenotype of Crohn's disease. Data from England 2016-2021

BACKGROUND AND STUDY AIMS

Isolated small bowel Crohn's disease (SBCD) is reported to have a worse prognosis compared to other CD phenotypes. The aim of this study was to understand the correlation between Isolated SBCD and ileocolonic disease with blood and faecal biomarkers and also to identify differences in outcome and management between the two phenotypes.

PATIENTS AND METHODS

Patients with ileocolonic or isolated small bowel Crohn's Disease (SBCD) were identified from an existing capsule endoscopy (CE) database. Harvey Bradshaw Index (HBI), biomarkers: c-reactive protein (CRP) and faecal calprotectin (FC), Lewis score and findings on CE and subsequent follow up data were collected. SPSS was used to analyse the data.

RESULTS

In total 248 patients were included in the study. Patients were split into two groups- Isolated SBCD with 178 patient (median age 44 years (IQR 31-56); 41.5 % male) and Ileocolonic Crohn's with 70 patients (median age 31 years (IQR 22.7-49); 31.5 % male). A new diagnosis of SBCD was made in 38.7 % (n = 96), whilst 60.0 % (n = 144) had established CD. Patients with ileocolonic disease had a higher HBI in comparison to isolated SBCD [HBI = 7 (IQR 5-10) vs HBI = 6(IQR 4-9); P = 0.04 ]. There was no significant difference in the FC levels between isolated SBCD and ileocolonic disease [136ug/g (IQR 53.8-363.3) vs 171ug/g (IQR 68.5-485.5); p = 0.98]. In isolated SBCD group, 30.3 % (n = 54) CE showed proximal disease, 96 % (n = 171) showed distal disease and 26.4 % (n = 47) showed extensive disease. SBCE was superior to MRI at diagnosing proximal SBCD (P < 0.01). On multivariate logistic regression, we did not identify any predictors of disease severity defined as Lewis score > 790. Following SBCE, 68.5 % (n = 170) of the total patients had a management change. This included commencement or dose escalation of corticosteroids in 123 (49.5 %) patients, azathioprine in 80 (33.3 %) patients, methotrexate in 22 (9.1 %) patients and biological therapy in 110 (44.3 %) patients. HBI predicted a change in management (p < 0.01).

CONCLUSION

CE is an important modality for the diagnosis of active SBCD. It also helps guide treatment in patients identified with active disease.

A novel location classification system for Crohn's disease based on small bowel involvement: a better predictor of disease progression

BACKGROUND

Small bowel involvement is related to poor prognosis in Crohn's disease (CD), which may be a potential marker to stratify patients with a high risk of progression. This study aimed to establish a novel location classification system for CD and to develop a predictive model for disease progression.

METHODS

Consecutive patients with non-stricturing/non-penetrating CD were retrospectively included in the Sixth Affiliated Hospital, Sun Yat-sen University (Guangzhou, P. R. China) between January 2012 and January 2018. Patients were classified into two groups according to disease location: small bowel involvement group and isolated colon group. The primary outcome was disease progression to stricturing or penetrating phenotypes. Progression-free survival was estimated using Cox proportional hazards regression analysis and Kaplan-Meier method.

RESULTS

A total of 463 patients were analysed, with a median follow-up time of 55.3 months. Patients with small bowel involvement had a higher risk of disease progression than those with isolated colon disease (hazard ratio = 1.998, P = 0.007), while no differences were found between Montreal location classification and disease progression. Median progression-free survival was higher in the isolated colon group than in the small bowel involvement group (84.5 vs 77.3 months, P = 0.006). Four independent factors associated with disease progression were identified: small bowel involvement, duration of onset of >1 year, deep mucosal ulcer, and C-reactive protein levels of ≥10 mg/L (all P < 0.05). The nomogram model based on these factors showed good performance in predicting disease progression, with a C-index of 0.746 (95% confidence interval, 0.707-0.785).

CONCLUSIONS

Classifying CD based on small bowel involvement and isolated colon was superior to the Montreal location classification for predicting disease progression.

Serum food specific IgG antibodies are associated with small bowel inflammation in patients with Crohn's disease

BACKGROUND/AIMS

Food antigens are thought to play a vital role in the initiation and perpetuation of Crohn's disease (CD). The main purpose of this study was to evaluate the potential association of serum food specific IgG antibodies and small bowel (SB) inflammation in CD patients.

METHODS

We conducted a prospective observational study with 96 CD patients. Demographic, disease-related data and inflammatory parameters were collected. Serum food IgG antibodies were measured using enzyme-linked immunosorbent assay (ELISA). Capsule endoscopy was performed to detect SB inflammation quantified by the Lewis Score.

RESULTS

Seventy-eight of (81.3%) CD patients were detected positive for at least one food-specific antibody. The five most prevalent food antibodies in CD patients were tomato, egg, corn, rice, and soybean. Patients with SB inflammation had a higher positive rate of food IgG antibodies (P = 0.010) and more IgG-positive food items (P = 0.010) than those without. Specifically, patients with SB inflammation were more likely to have positive food-specific IgG against egg (P = 0.014), corn (P = 0.014), and wheat (P = 0.048). Additionally, the number of positive food IgGs ≥ 3 and elevated ESR were independently associated with concurrent SB inflammation (P = 0.015 and P = 0.013, respectively).

CONCLUSION

Our study confirmed that CD patients with SB inflammation had a higher positive rate of food IgG antibodies and more IgG-positive food items. The number of food positive IgGs ≥ 3 and elevated ESR were independently associated with concurrent SB inflammation.

Small-bowel capsule endoscopy and device-assisted enteroscopy for diagnosis and treatment of small-bowel disorders: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2022

MR1: ESGE recommends small-bowel capsule endoscopy as the first-line examination, before consideration of other endoscopic and radiological diagnostic tests for suspected small-bowel bleeding, given the excellent safety profile of capsule endoscopy, its patient tolerability, and its potential to visualize the entire small-bowel mucosa.Strong recommendation, moderate quality evidence. MR2: ESGE recommends small-bowel capsule endoscopy in patients with overt suspected small-bowel bleeding as soon as possible after the bleeding episode, ideally within 48 hours, to maximize the diagnostic and subsequent therapeutic yield.Strong recommendation, high quality evidence. MR3: ESGE does not recommend routine second-look endoscopy prior to small-bowel capsule endoscopy in patients with suspected small-bowel bleeding or iron-deficiency anemia.Strong recommendation, low quality evidence. MR4: ESGE recommends conservative management in those patients with suspected small-bowel bleeding and high quality negative small-bowel capsule endoscopy.Strong recommendation, moderate quality evidence. MR5: ESGE recommends device-assisted enteroscopy to confirm and possibly treat lesions identified by small-bowel capsule endoscopy.Strong recommendation, high quality evidence. MR6: ESGE recommends the performance of small-bowel capsule endoscopy as a first-line examination in patients with iron-deficiency anemia when small bowel evaluation is indicated.Strong recommendation, high quality evidence. MR7: ESGE recommends small-bowel capsule endoscopy in patients with suspected Crohn's disease and negative ileocolonoscopy findings as the initial diagnostic modality for investigating the small bowel, in the absence of obstructive symptoms or known bowel stenosis.Strong recommendation, high quality evidence. MR8: ESGE recommends, in patients with unremarkable or nondiagnostic findings from dedicated small-bowel cross-sectional imaging, small-bowel capsule endoscopy as a subsequent investigation if deemed likely to influence patient management.Strong recommendation, low quality evidence. MR9: ESGE recommends, in patients with established Crohn's disease, the use of a patency capsule before small-bowel capsule endoscopy to decrease the capsule retention rate.Strong recommendation, moderate quality evidence. MR10: ESGE recommends device-assisted enteroscopy (DAE) as an alternative to surgery for foreign bodies retained in the small bowel requiring retrieval in patients without acute intestinal obstruction.Strong recommendation, moderate quality evidence. MR11: ESGE recommends DAE-endoscopic retrograde cholangiopancreatography (DAE-ERCP) as a first-line endoscopic approach to treat pancreaticobiliary diseases in patients with surgically altered anatomy (except for Billroth II patients).Strong recommendation, moderate quality evidence.

Prevention and Alleviation of Dextran Sulfate Sodium Salt-Induced Inflammatory Bowel Disease in Mice With Bacillus subtilis-Fermented Milk via Inhibition of the Inflammatory Responses and Regulation of the Intestinal Flora

The pathogenesis of inflammatory bowel disease (IBD) might be related to the local inflammatory damage and the dysbacteriosis of intestinal flora. Probiotics can regulate the intestinal flora and ameliorate IBD. The probiotic Bacillus subtilis strain B. subtilis JNFE0126 was used as the starter of fermented milk. However, the therapeutic effects of B. subtilis-fermented milk on IBD remain to be explored. In this research, the therapeutic effect of B. subtilis-fermented milk on dextran sulfate sodium salt (DSS)-induced IBD mouse model was evaluated. Besides, the expression of pro-inflammatory/anti-inflammatory cytokines, the proliferation of the intestinal stem cells, and the reconstruction of the mucosa barrier were investigated. Finally, alteration of the gut microbiota was investigated by taxonomic analysis. As shown by the results, the disease activity index (DAI) of IBD was significantly decreased through oral administration of B. subtilis (JNFE0126)-fermented milk, and intestinal mucosa injury was attenuated. Moreover, B. subtilis could reduce the inflammatory response of the intestinal mucosa, induce proliferation of the intestinal stem cell, and promote reconstruction of the mucosal barrier. Furthermore, B. subtilis could rebalance the intestinal flora, increasing the abundance of Bacillus, Alistipes, and Lactobacillus while decreasing the abundance of Escherichia and Bacteroides. In conclusion, oral administration of the B. subtilis-fermented milk could alleviate DSS-induced IBD via inhibition of inflammatory response, promotion of the mucosal barrier reconstruction, and regulation of the intestinal flora.

Surgical treatment of intestinal stricture in inflammatory bowel disease

Fibroblast infiltration and collagen deposition result in structural changes in the bowel wall, and lead to strictures in intestinal inflammatory disease. While strictures can also occur in other contexts, such as malignancy, this review focuses on the surgical treatment of stricture secondary to inflammatory bowel disease. Distinguishing between predominantly inflammation vs established fibrosis as the cause of a stricture can be challenging. While inflammatory strictures may be responsive to medication, predominantly fibrotic strictures usually need surgical intervention. Both endoluminal and extraluminal approaches are described in this review. Endoscopic dilatation of strictures is suitable for short-segment isolated small bowel strictures. Other options are to divide the stricture surgically but preserve the length, performing a strictureplasty or resecting the strictured segment. The mesentery is increasingly recognized as playing a role in stricture recurrence. In a relapsing-remitting disease such as Crohn's disease, the preservation of intestinal length is essential and balance is needed between this and a complete resection to reduce the risk of recurrence. Pre- and postoperative involvement of the multidisciplinary team is essential to improve outcomes in this challenging clinical scenario.