クローン病

OBJECTIVES: Children with inflammatory bowel disease (IBD) are at increased risk for Clostridioides difficile infection (CDI), which is associated with worse clinical outcomes. We aimed to assess current diagnostic and therapeutic practices for CDI among Italian pediatric IBD centers. METHODS: A nationwide survey was conducted in 2025 using a structured 28-item questionnaire distributed to all pediatric IBD centers in Italy. Items addressed diagnostic strategies, treatment approaches, recurrence management, and immunosuppressive therapy handling in children with IBD and CDI. RESULTS: Twenty-seven centers responded (response rate, 90%). Diagnostic approaches varied: toxin enzyme immunoassays (EIA) were indicated by 21/27 centers (78%), glutamate dehydrogenase (GDH) testing by 19/27 (70%), and nucleic acid amplification tests (NAAT) by 13/27 (48%). Routine CDI testing at IBD diagnosis was indicated by 12/27 centers (44%), whereas 23/27 (85%) reported testing during IBD flares. For a first non-severe episode, vancomycin and metronidazole were equally identified as preferred first-line options (18/27; 66% each). Oral vancomycin was the preferred treatment for recurrent CDI (26/27; 96%). Third or subsequent recurrences prompted consideration of fidaxomicin (19/27; 70%), fecal microbiota transplantation (6/27; 22%), and bezlotoxumab (2/27; 7%). In fulminant CDI, 7/27 centers (26%) indicated adding fidaxomicin to standard therapy. In acute severe colitis with concomitant CDI at diagnosis, 18/27 centers (67%) described a cautious approach to biologic initiation. CONCLUSIONS: This nationwide survey highlights substantial unmet needs in CDI management in pediatric IBD, including variability in diagnostic strategies, lack of consensus on first-line therapy, and uncertainty regarding immunosuppressive management, supporting the need for evidence-based pediatric-specific guidelines.

BACKGROUND: Postoperative recurrence is common after ileocolonic resection for Crohn's disease (CD). Comparative effectiveness data for advanced treatments for preventing recurrence is limited. METHODS: We conducted a population-based retrospective cohort study of adults with CD undergoing ileocolonic resection with primary anastomosis in the Calgary Health Zone, Canada (2016-2020). The primary outcome was endoscopic recurrence within 18 months, assessed using the modified Rutgeerts score as an ordinal endpoint. High-risk recurrence (modified Rutgeerts score ≥i2b) was evaluated as a secondary outcome. Propensity scores were estimated using established clinical risk factors and inverse probability of treatment weighting (IPTW) targeting the average treatment effect among treated patients was applied to ordinal and logistic regression models. Treatment effects were expressed as adjusted odds ratios (aOR) with 95% CI. RESULTS: Among 231 patients, 126 (54.5%) received biologic prophylaxis and 92 (39.8%) received no treatment; endoscopy was performed in 217 patients. High-risk endoscopic recurrence occurred in 42.3% (36/85) of untreated patients compared with 9.4% (6/64) receiving TNF antagonists, 27.8% (10/36) receiving ustekinumab, and 10.0% (2/20) receiving vedolizumab. After weighting for established risk factors for recurrence, all biologic strategies were associated with reduced odds of endoscopic recurrence compared to no treatment (aOR 0.15-0.31, all p<0.05). Vedolizumab was associated with lower odds of recurrence compared with ustekinumab (aOR 0.24 [0.06-0.92], p=0.04) but not TNF antagonists (aOR 0.43 [0.10-1.87], p=0.26). CONCLUSIONS: In this real-world cohort, biologic prophylaxis is associated with reduced endoscopic recurrence in CD. Both ustekinumab and vedolizumab are effective options, including after prior TNF exposure.

BACKGROUND: Surgical rates for Crohn's disease (CD) are declining globally. However, the driving factors remain unclear, particularly in newly industrialized countries. We aimed to evaluate the impact of diagnostic capacity and treatment with biologics on surgical rates among Chinese CD patients. METHODS: Data of CD patients from January 2000 to January 2024 were extracted from 8 sites of the Chinese database for inflammatory bowel disease. Trends in cross-sectional imaging use, surgically diagnosed proportion, medical treatment, and surgery for CD were described. Cumulative surgical rates were compared using Kaplan-Meier method with log-rank test. Time-dependent Cox models were used to identify factors associated with surgery risk, and propensity score matching (PSM) was applied to validate the findings. RESULTS: In total, 1354 patients were included, with a median follow-up of 5.99 years. The cumulative 5-year surgical rate decreased from 30.96% in 2000-2012 to 21.57% in 2013-2024 (log-rank P <0.001). The use of cross-sectional imaging increased from 2.00% in 2000-2004 to 82.81% in 2020-2024. The proportion of surgically diagnosed patients declined from 13.68% in 2000-2012 to 6.21% in 2013-2024. Multivariate Cox analysis showed that diagnosis in 2013-2024 (hazard ratio [HR] 0.74, 95% confidence interval [CI]: 0.59-0.91, P = 0.006) was independently associated with a lower risk of surgery, whereas biologic use (HR 0.93, 95% CI: 0.71-1.22, P = 0.604) was not. Sensitivity analyses excluding surgically diagnosed patients demonstrated similar surgical rates between the two cohorts. PSM and subgroup analyses confirmed these trends. CONCLUSIONS: Surgical rates among Chinese CD patients have significantly decreased over the past two decades, in parallel with improvements in diagnosis. Enhancements in diagnostic pathways within broader systemic healthcare upgrades are strongly associated with reduced surgical risk, whereas increased use of biologics is not.

BACKGROUND/AIMS: Inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC), is increasing in East Asia. Most known susceptibility loci, identified primarily in Europeans, remain insufficient to explain clinical heterogeneity in Asians. We performed whole-exome sequencing in Korean IBD patients to identify population-specific variants influencing age at diagnosis. METHODS: We analyzed 341 Korean IBD patients (192 CD, 149 UC) from three cohorts. Case-control analysis with external controls was confounded by platform heterogeneity, so we used a within-case Cox proportional hazards model instead. Variants were prioritized using a dual-threshold strategy. Gene-level analysis identified subtype-specific pathways, and disease progression was assessed in patients with longitudinal data (n = 206). RESULTS: We identified 12 novel rare variants (minor allele frequency < 0.01 in gnomAD) predominantly observed in East Asian populations. One variant in GSG1 (rs146166808) reached genome-wide significance (p = 3.39 × 10-8); carriers showed accelerated disease onset and increased risk of aggressive progression (OR = 12.52, p = 0.050). Subtype-specific analyses identified two variants for CD (GSG1, CYP2D6) and five for UC (including IGLL1). Gene-level analysis revealed distinct genetic architectures: CD showed enrichment for axon guidance pathways (p = 0.000065), whereas UC showed enrichment for calcium signaling and tissue maintenance pathways (p = 0.00068). CONCLUSION: We identified population-specific rare variants influencing disease onset and progression in Korean IBD. Distinct genetic architectures underlying CD and UC provide insight into IBD heterogeneity and potential therapeutic targets in this population.

Over the past two decades, the small bowel, once considered a diagnostic "blind spot," has become fully and comprehensively accessible. This review summarizes recent advances in the main diagnostic modalities: capsule endoscopy (CE), device-assisted enteroscopy (DAE), computed tomography enterography (CTE), magnetic resonance enterography (MRE), and intestinal ultrasound (IUS). CE provides a noninvasive assessment of mucosal abnormalities, whereas DAE offers the added benefits of tissue sampling and therapeutic intervention. CTE and MRE provide complementary cross-sectional information on mural inflammation, strictures, and extraintestinal involvement. IUS has emerged as a valuable, radiation-free technique for repeated bedside monitoring. We review the diagnostic performance, strengths, and limitations of each modality in key clinical scenarios, including suspected small bowel bleeding, Crohn's disease, and tumors. Finally, we highlight the importance of an integrated, patient-centered approach to optimize the evaluation of small bowel disease and to guide clinical decision-making.