Prevalence, incidence, and treatment patterns of fistulizing Crohn disease: A US population-based cohort study.

BACKGROUND: Population-based studies for patients with fistulizing Crohn disease (CD), a severe complication of CD, are limited. OBJECTIVE: To report estimates of the prevalence and incidence rates of fistulizing CD in the United States and examine associated treatment patterns among incident cases. METHODS: This retrospective, observational cohort study used a US administrative claims database from January 1, 2016, to December 31, 2019, with at least 365 days' continuous insurance enrollment. The prevalent patient population comprised patients with incident or existing cases of fistulizing CD. Crude, age, and sex-adjusted prevalence and incidence rates of fistulizing CD were estimated. Baseline characteristics, comorbidities, and CD-related medications and medical procedures were examined for patients with fistulizing CD. RESULTS: The overall crude prevalence (prevalent cases: n = 5,082) and incidence rates (incident cases: n = 2,399) between 2017 and 2019 were 25.2 (95% CI = 24.5-25.9) per 100,000 persons and 6.9 (95% CI = 6.6-7.1) per 100,000 person-years, respectively. Age- and sex-adjusted prevalence and incidence rates were 24.9 (95% CI = 24.2-25.6) per 100,000 persons and 7.0 (95% CI = 6.7-7.3) per 100,000 person-years, respectively. Approximately half of all patients with incident fistulizing CD were prescribed biologic therapies within 1 year of an incident fistula diagnosis, with anti-tumor necrosis factor therapies the most widely prescribed biologic class; antibiotic and corticosteroid use was also common. Among the incident cases, approximately one-third of patients required surgery during the follow-up period, most of which occurred within 3 months of the index date. CONCLUSIONS: This study reports age- and sex-adjusted prevalence and incidence rates for fistulizing CD of 24.9 per 100,000 persons and 7.0 per 100,000 person-years, respectively. As a concerning complication of CD, first-year treatment of fistulas in the United States commonly includes anti-tumor necrosis factor therapy, and there is a considerable surgical burden.

[A new treatment option for complex perianal fistulas in Crohn's disease patients; development of darvadstrocel (allogeneic expanded adipose-derived mesenchymal stem cells) in Japan].

Crohn's disease (CD) is a chronic and relapsing inflammatory bowel disease affecting the entire gastrointestinal tract. The prevalence of CD among Japanese people is increasing. One of the most frequent complications of CD is perianal fistulas. People living with CD may experience complex perianal fistulas, which can cause intense pain, bleeding, swelling, infection, and anal discharge. Despite medical and surgical advancements, complex perianal fistulas in CD remain challenging for clinicians to treat. CD patients living with perianal fistulas reported a negative impact on many aspects of their quality of life. Darvadstrocel is a cell therapy product containing a suspension of allogeneic expanded adipose-derived mesenchymal stem cells. It has been approved in Europe and Japan for the treatment of complex perianal fistulas that have shown an inadequate response to at least one conventional or biologic therapy in adult patients with non-active/mildly active luminal CD. By exhibiting immunomodulatory and local anti-inflammatory effects at the site of inflammation, it offers a new treatment option for complex perianal fistulas in CD patients. In this manuscript, the characteristic of darvadstrocel, the summary of results from the pivotal phase 3 studies in Europe and Japan, and the development strategy in Japan were introduced.

Clinical and health care utilization variables can predict 90-day hospital re-admission in adults with Crohn's disease for point of care risk evaluation.

BACKGROUND: Hospital re-admission for persons with Crohn's disease (CD) is a significant contributor to morbidity and healthcare costs. We derived prediction models of risk of 90-day re-hospitalization among persons with CD that could be applied at hospital discharge to target outpatient interventions mitigating this risk. METHODS: We performed a retrospective study in persons with CD admitted between 2009 and 2016 for an acute CD-related indication. Demographic, clinical, and health services predictor variables were ascertained through chart review and linkage to administrative health databases. We derived and internally validated a multivariable logistic regression model of 90-day CD-related re-hospitalization. We selected the optimal probability cut-point to maximize Youden's index. RESULTS: There were 524 CD hospitalizations and 57 (10.9%) CD re-hospitalizations within 90 days of discharge. Our final model included hospitalization within the prior year (adjusted odds ratio [aOR] 3.27, 95% confidence interval [CI] 1.76-6.08), gastroenterologist consultation within the prior year (aOR 0.185, 95% CI 0.0950-0.360), intra-abdominal surgery during index hospitalization (aOR 0.216, 95% CI 0.0500-0.934), and new diagnosis of CD during index hospitalization (aOR 0.327, 95% CI 0.0950-1.13). The model demonstrated good discrimination (optimism-corrected c-statistic value 0.726) and excellent calibration (Hosmer-Lemeshow goodness-of-fit p-value 0.990). The optimal model probability cut point allowed for a sensitivity of 71.9% and specificity of 70.9% for identifying 90-day re-hospitalization, at a false positivity rate of 29.1% and false negativity rate of 28.1%. CONCLUSIONS: Demographic, clinical, and health services variables can help discriminate persons with CD at risk of early re-hospitalization, which could permit targeted post-discharge intervention.

A phase I/II clinical trial of ex-vivo expanded human bone marrow derived allogeneic mesenchymal stromal cells in adult patients with perianal fistulizing Crohn's Disease.

BACKGROUND: Perianal fistulas (PF) affect one-third patients with Crohn's disease (CD) with limited therapeutic options. There is dearth of literature on safety and efficacy of bone marrow-derived mesenchymal stromal cells (BMSCs) in this population. METHODS: An open-label, phase I/II, single-arm study was conducted involving local administration of human allogeneic bone marrow-derived mesenchymal stromal cells in perianal fistula of patients with Crohn's disease refractory to standard therapies. Clinical severity and biomarkers were assessed at baseline and periodically until week 104 , and MRI at week 24 and 104. Primary and secondary objectives were to assess safety and efficacy respectively. Fistula remission was complete closure of fistula openings with < 2 cm perianal collection on MRI, and fistula response was decrease in drainage by ≥ 50%. Change in perianal disease activity index, quality-of-life and Van Assche index on MRI over time was assessed using mixed-effect linear regression model. RESULTS: Ten patients (male:8, mean age:27.4 ± 12.0years) were recruited. Self-resolving procedure-related adverse events occurred in three patients, with no follow-up adverse events. In intention to treat analysis at week 24, two patients (20%) achieved fistula remission and seven (70%) had fistula response. At week 52, two (20%) patients were in remission and seven (70%) maintained response. At 104 weeks, two (20%) patients maintained response and one (10%) was in remission. Statistically significant decrease in perianal disease activity index (P = 0.008), Van Assche Index (P = 0.008) and improvement in quality-of-life (P = 0.001) were observed over time. CONCLUSIONS: Allogeneic BMSCs are safe and effective for the treatment of perianal fistulizing CD with significant improvement in clinical severity and radiological healing. TRIAL REGISTRATION: The study was prospectively registered on Clinical trials registry - India (CTRI), CTRI/2020/01/022743 on 14 January 2020, http://ctri.nic.in .

Novel biomarker profiles to improve individual diagnosis and prognosis in patients with suspected inflammatory bowel disease: protocol for the Nordic inception cohort study (NORDTREAT).

INTRODUCTION: Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, can be challenging to diagnose, and treatment outcomes are difficult to predict. In the NORDTREAT cohort study, a Nordic prospective multicentre study, we aim to identify novel molecular biomarkers of diagnostic value by assessing the diagnostic test accuracy (cross-sectionally), as well as the prognostic utility when used as prognostic markers in the long-term (cohort study). In the diagnostic test accuracy study, the primary outcome is a successful diagnosis using one or more novel index tests at baseline compared with the ECCO criteria as the reference standard. The composite outcome of the prognostic utility study is 'severe IBD' within 52 weeks from inclusion, defined as one or more of the following three events: IBD-related surgery, IBD-related hospitalisation or IBD-related death. METHODS AND ANALYSIS: We aim to recruit 800 patients referred on suspicion of IBD to this longitudinal observational study, a collaboration between 11 inclusion sites in Denmark, Iceland, Norway and Sweden. Inclusion will occur from February 2022 until December 2023 with screening and baseline visits for all participants and three outcome visits at weeks 12, 26 and 52 after baseline for IBD-diagnosed patients. Biological material (blood, faeces, biopsies, urine and hair), clinical data and lifestyle information will be collected during these scheduled visits. ETHICS AND DISSEMINATION: This study will explore novel biomarkers to improve diagnostic accuracy and prediction of disease progression, thereby improving medical therapy and the quality of life for patients with IBD.The study is approved by the Ethics Committee (DK: S-20200051, v1.4, 16.10.2021; IS: VSNb2021070006/03.01, NO: 193064; SE: DNR 2021-05090) and the Danish Data Protecting Agency (20/54594). Results will be disseminated through peer-reviewed journals, patient associations and presentations at international conferences. CLINICAL TRIAL REGISTRATION NUMBER: NCT05414578; Pre-results.

Multicenter registry of pediatric inflammatory bowel disease from a developing country.

BACKGROUND: Despite the rising incidence of pediatric inflammatory bowel disease (PIBD) globally, multicenter collaborative studies of PIBD children among developing countries remain sparse. We therefore aimed to define the initial presentation and short-term outcomes of Thai children with PIBD from a multicenter registry. METHODS: Four teaching hospitals participated in this study. A diagnosis of PIBD requires gastrointestinal endoscopy and histopathology in children aged < 19 years. Besides demographics, we collected clinical information and treatment with the data at 1-year follow up. RESULTS: We included 35 Crohn's disease (CD), one IBD-unclassified, and 36 ulcerative colitis (UC) children (total n = 72 with 60.6% males). The mean age at diagnosis was 7.9 years (SD 4.1) with 38% being very early onset IBD (VEO-IBD). When compared with UC, the CD children were more likely to exhibit fever (42.3 vs. 13.9%), weight loss/failure to thrive (68.6 vs. 33.3%), and hypoalbuminemia (62.9 vs. 36.1%) but less likely to have bloody stools (51.4 vs. 91.7%) (all P < 0.05). No significant differences in demographics, clinical data and medications used with regards to VEO-IBD status. At 1 year after diagnosis (n = 62), 30.7% failed to enter clinical remission and 43.7% remained on systemic corticosteroids. Diarrhea (OR 9.32) and weight issues (OR 4.92) at presentation were independent predictors of failure to enter clinical remission; and females (OR 3.08) and CD (vs. UC) (OR 3.03) were predictors of corticosteroids use at 1-year follow-up. CONCLUSIONS: A high proportion of VEOIBD is noted, and CD was more likely to present with significant inflammatory burden. Diarrhea and weight issues at presentation were independent predictors of failure to enter clinical remission; and females and CD (vs. UC) were predictors of corticosteroids use at 1-year follow-up.

Pre-Diagnosis Diet Predicts Response to Exclusive Enteral Nutrition and Correlates with Microbiome in Pediatric Crohn Disease.

Exclusive enteral nutrition (EEN) is effective in inducing remission in pediatric Crohn disease (CD). EEN alters the intestinal microbiome, but precise mechanisms are unknown. We hypothesized that pre-diagnosis diet establishes a baseline gut microbiome, which then mediates response to EEN. We analyzed prospectively recorded food frequency questionnaires (FFQs) for pre-diagnosis dietary patterns. Fecal microbiota were sequenced (16SrRNA) at baseline and through an 18-month follow-up period. Dietary patterns, Mediterranean diet adherence, and stool microbiota were associated with EEN treatment outcomes, disease flare, need for anti-tumor necrosis factor (TNF)-α therapy, and long-term clinical outcomes. Ninety-eight patients were included. Baseline disease severity and microbiota were associated with diet. Four dietary patterns were identified by FFQs; a "mature diet" high in fruits, vegetables, and fish was linked to increased baseline microbial diversity, which was associated with fewer disease flares (p < 0.05) and a trend towards a delayed need for anti-TNF therapy (p = 0.086). Baseline stool microbial taxa were increased (Blautia and Faecalibacterium) or decreased (Ruminococcus gnavus group) with the mature diet compared to other diets. Surprisingly, a "pre-packaged" dietary pattern (rich in processed foods) was associated with delayed flares in males (p < 0.05). Long-term pre-diagnosis diet was associated with outcomes of EEN therapy in pediatric CD; diet-microbiota and microbiota-outcome associations may mediate this relationship.

Perceptions, behaviours and barriers towards exercise practices in inflammatory bowel disease.

Inflammatory bowel disease (IBD), a chronic disease affecting the digestive tract, has a significant impact on health-related quality of life. Pharmaceutical treatment is typically adopted, yet exercise is increasingly becoming recognized as an adjunct therapy. This study aimed to explore the perspectives, behaviours, and barriers of IBD patients in terms of their exercise habits. A 16-item closed-ended questionnaire was completed by 463 adult IBD patients (Ulcerative colitis = 57.02%, Crohn's dis-ease = 40.60% and Other = 2.38%) (Female = 76.67%, Male = 22.46 and Non-binary = 0.86%). The questionnaire was divided into three sections: baseline/demographic characteristics, disease characteristics, and exercise perceptions, beliefs, and behaviours. Significantly (P<0.001) more participants (63.07%) reported that they engage regularly with exercise compared to those who do not; however, engagement was significantly lower in female patients (59.72%) compared to males (74.04%). Respondents also rated significantly (P<0.001) that a combination of factors prevents engagement in exercise (74.30%). Moderate intensity exercise was the predominant (P<0.001) aerobic modality (39.04%), the majority (P<0.001) response was that patients undertake no resistance training (27.74%), and significantly more (P<0.001) patients indicated that they don't know whether resistance training can influence IBD either positively (57.53%) or negatively (62.33%). Whilst it is encouraging that IBD patients are engaging regularly with exercise, the reduced levels of engagement in females and lack of knowledge/ engagement with resistance training, indicate that future implementation and educational developments are necessary to enhance exercise in females and resistance training engagement in all IBD patients.

Is There Evidence of Crohn's Disease Exclusion Diet (CDED) in Remission of Active Disease in Children and Adults? A Systematic Review.

Crohn's disease (CD) is an inflammatory bowel disease. Previous research has explored the impact of diet on CD, as specific dietary components can influence gut microbiota and immune responses, contributing to damage in the gastrointestinal tract. The Crohn's Disease Exclusion Diet (CDED) is based on an exclusion diet; it is a recent dietary approach that is often used alongside partial enteral nutrition (PEN) and aims to induce disease remission by excluding certain dietary components. This study assesses the current evidence for the effectiveness of the CDED + PEN in achieving remission in both children and adults with active CD. Our systematic review followed PRISMA recommendations and was registered in PROSPERO with CRD number 42022335076. The searched databases were PubMed/MEDLINE, Cochrane Library, Scopus, and Web of Science. The included studies were analyzed using Rayyan software, and the risk of bias was assessed with Cochrane RevMan 5.0 software. The primary assessed outcome was clinical remission, evaluated with validated questionnaire scores such as PCDAI, CDAI, or HBI. All analyzed papers yielded promising results. Notably, the CDED + PEN demonstrated better tolerance than exclusive enteral nutrition (EEN), resulting in higher adherence rates. Therefore, the CDED + PEN appears to be a viable alternative for induction remission in active disease for both children and adults with CD.

Gut metabolome and microbiota signatures predict response to treatment with exclusive enteral nutrition in a prospective study in children with active Crohn's disease.

BACKGROUND: Predicting response to exclusive enteral nutrition (EEN) in active Crohn's disease (CD) could lead to therapy personalization and pretreatment optimization. OBJECTIVES: This study aimed to explore the ability of pretreatment parameters to predict fecal calprotectin (FCal) levels at EEN completion in a prospective study in children with CD. METHODS: In children with active CD, clinical parameters, dietary intake, cytokines, inflammation-related blood proteomics, and diet-related metabolites, metabolomics and microbiota in feces, were measured before initiation of 8 wk of EEN. Prediction of FCal levels at EEN completion was performed using machine learning. Data are presented with medians (IQR). RESULTS: Of 37 patients recruited, 15 responded (FCal < 250 µg/g) to EEN (responders) and 22 did not (nonresponders). Clinical and immunological parameters were not associated with response to EEN. Responders had lesser (µmol/g) butyrate [responders: 13.2 (8.63-18.4) compared with nonresponders: 22.3 (12.0-32.0); P = 0.03], acetate [responders: 49.9 (46.4-68.4) compared with nonresponders: 70.4 (57.0-95.5); P = 0.027], phenylacetate [responders: 0.175 (0.013-0.611) compared with nonresponders: 0.943 (0.438-1.35); P = 0.021], and a higher microbiota richness [315 (269-347) compared with nonresponders: 243 (205-297); P = 0.015] in feces than nonresponders. Responders consumed (portions/1000 kcal/d) more confectionery products [responders: 0.55 (0.38-0.72) compared with nonresponders: 0.19 (0.01-0.38); P = 0.045]. A multicomponent model using fecal parameters, dietary data, and clinical and immunological parameters predicted response to EEN with 78% accuracy (sensitivity: 80%; specificity: 77%; positive predictive value: 71%; negative predictive value: 85%). Higher taxon abundance from Ruminococcaceae, Lachnospiraceae, and Bacteroides and phenylacetate, butyrate, and acetate were the most influential variables in predicting lack of response to EEN. CONCLUSIONS: We identify microbial signals and diet-related metabolites in feces, which could comprise targets for pretreatment optimization and personalized nutritional therapy in pediatric CD.

Biological treatment approach to inflammatory bowel disease is similar in academic and nonacademic centres - prime time for decentralisation of inflammatory bowel disease care?

BACKGROUND: With the increasing number of inflammatory bowel disease (IBD) patients, it is difficult to manage them within specialised IBD teams in academic medical centres: many are therefore treated in nonacademic IBD centres. It is unclear whether the time to introducing biologics is the same in both settings. AIM: We aimed to compare treatment approach with biologics in academic vs. nonacademic centres. METHODS: We analysed Slovenian national IBD registry data (UR-CARE Registry, supported by the European Crohn's and Colitis Organisation), which included 2 academic (2319 patients) and 4 nonacademic IBD (429 patients) centres. RESULTS: The disease phenotype was similar in both settings. In total, 1687 patients received 2782 treatment episodes with biologics. We observed no differences in treatment episodes with TNF-alpha inhibitors (60% vs. 61%), vedolizumab (24% vs. 23%), or ustekinumab (17% vs. 16%) in academic compared to nonacademic centres ( P  = 0.949). However, TNF inhibitors were less often the first biologic in academic centres (TNF inhibitors: 67.5% vs. 74.0%, vedolizumab: 20.3% vs. 17.9%, ustekinumab: 12.1% vs. 8.1%; P = 0.0096). Consequently, more patients received ustekinumab (29.8% vs. 18.3%) and vedolizumab (17.4% vs. 13.5%) and fewer TNF inhibitors (52.7% vs. 68.2%) for Crohn's disease in academic compared to nonacademic centres, with no such differences for ulcerative colitis. The time to initiation of the first biologic from diagnosis was short and similar in both settings (11.3 vs. 10.4 months, P  = 0.2). CONCLUSION: In this nationwide registry analysis, we observed that biological treatment choice was similar in academic and nonacademic settings. These findings support the decentralisation of IBD care.

Medical management of pediatric inflammatory bowel disease.

Management of inflammatory bowel disease, both Crohn's disease (CD) and ulcerative colitis (UC), has seen a seismic shift over the past decade. Over the past five years, there has been the introduction of many new therapies with differing mechanisms of action and a goal of achieving mucosal healing, as well as clinical and biochemical remission (1,2). In addition, management is aimed at restoring normal growth and normalizing quality of life. The ultimate goal is to individualize medical management and determine the right drug for the right patient by identifying which inflammatory pathway is predominant and avoiding unwarranted lack of efficacy or side effects through biomarkers and risk prognostication. Patient's age, location of disease, behavior (inflammatory vs. penetrating/structuring), severity and growth delay all play into deciding on the best treatment approach. Ultimately, early intervention is key in preventing complications. The therapeutic approaches to management can be broken down to nutritional therapy, biologic agents, immunomodulators (including corticosteroids), aminosalicylates and antibiotics. There are numerous other therapies, such as small molecule agents recently approved in adults, which are garnering a great deal of interest.

Recurrent Crohn's disease.

Although surgical management of the ileocolic segment in pediatric Crohn's disease is not curative, the main goal of therapy is to allow for growth, adequate nutrition, and age-appropriate development. Recurrent disease at the site of anastomosis presents as a major morbidity. Several factors have been implicated in the development of surgical recurrence though data in the literature is scarce. This review explores the epidemiology of recurrent ileocolic disease following primary surgery, indications for surgical intervention, and techniques reported in the literature. Pediatric data is scarce, and therefore, much of it is extrapolated from adult literature.

Perianal disease: Updates and controversies in closing the gaps.

Perianal complications are common and morbid in children with Crohn's disease. In this review, we describe the epidemiology, the presentation and diagnosis, evaluation and management. We focus on updates such as the increasing frequency of biologic medications and MRI for evaluation. We also highlight controversies on the timing and approaches to surgical techniques. Finally, perianal disease requires the coordination of multidisciplinary care with nursing, radiology, gastroenterology, and surgery to optimize outcomes - both medical and patient-centered.

Reverse-engineered exclusive enteral nutrition in pediatric Crohn's disease: A pilot trial.

BACKGROUND: In pediatric Crohn's disease (CD), commercial formulas used as exclusive enteral nutrition (EEN) are effective at inducing remission. This study aims to assess the impact of a whole-food blended smoothie as EEN on CD activity and the intestinal microbiome. METHODS: A 4-week prospective trial assessed the impact of EEN with a whole-food smoothie on newly diagnosed mild-to-moderate active pediatric CD. The smoothie with a multivitamin were developed to meet age-appropriate nutritional requirements. Assessment over 4 weeks included Pediatric Crohn's Disease Activity Index (PCDAI), serum laboratories, fecal calprotectin (FCP), and stool collection for metagenomic shotgun sequencing and microbiota composition analysis. Clinical remission was defined as PCDAI ≤ 10 at week 4. RESULTS: Ten participants were enrolled with median age 14.5 years, and 8 completed the trial. Baseline mean PCDAI was 26.3 ± 9.1 and mean FCP 1149 ± 718 µg/g. At week 4, 80% of participants achieved clinical remission. FCP decreased by over half in 60% of participants, with FCP below 250 µg/g in 60% and below 100 µg/g in 40%. Microbiome analysis showed a significant increase in species richness over 4 weeks (p = 0.01). Compared to baseline, the relative abundance at week 2 and at week 4 was significantly increased for Bifidobacterium and Streptococcus and decreased for Blautia (p < 0.05 for all). CONCLUSION: A whole-food blended smoothie was effective for inducing clinical remission and decreasing FCP in pediatric CD similar to commercial EEN formulas. Further research may give insight into data-driven whole-food dietary approaches for CD management. CLINICALTRIALS: gov NCT03508193.

hUC-MSCs therapy for Crohn's disease: efficacy in TNBS-induced colitis in rats and pilot clinical study.

BACKGROUND: The use of mesenchymal stem cells (MSCs) has recently emerged as a promising new therapeutic strategy for many diseases including perianal fistulizing Crohn's disease (CD). Whether hUC-MSCs can promote the healing of luminal ulcer in CD has not been studied so far. METHODS: The model of TNBS-induced colitis in rats was used to confirm the efficacy of hUC-MSCs in the treatment of CD. Then, seventeen CD patients refractory to or unsuitable for currently available therapies were enrolled and received once submucosal local injection through colonoscopy combined with once intravenous drip on the next day. All patients received a 24-week follow-up. Clinical and laboratory assessments were monitored at baseline, week 4, 8, 12, and 24. Endoscopic evaluations were conducted at baseline and week 12. Mucosal specimens were obtained at the margin of lesions by endoscopy biopsies and used for RNA sequencing. Two hUC-MSCs co-culture systems were established in vitro, one with the mucosa specimens and the other with M1 macrophages induced from THP1. The expressions of genes representing inflammation (TNFα, IL-6, and IL-1ß) and intestinal barrier function (ZO1, CLAUDIN1, and CDH1) were tested by RT-PCR. FINDINGS: hUC-MSCs treatment increased body weight and decreased disease activity index (DAI), colon macroscopic damage index (CMDI), and histopathological score (HPS) of rats with TNBS-induced colitis. The results of the clinical study also showed that this mode of hUC-MSCs application was associated with regression of intestinal ulceration. Eight patients (47%) got endoscopic responses (SES-CD improvement of ≥50% from baseline) and three patients (17.65%) got mucosal healing (SES-CD is zero), with a parallel improvement of clinical and laboratory parameters without serious adverse events. RNA sequencing showed hUC-MSCs therapy was associated with an upregulation of transcripts linked to intestinal epithelial barrier integrity and a downregulation of inflammatory signaling pathways in the intestinal mucosa, especially the TNF signaling pathway, IL-17 signaling pathway, and TLR signaling pathway. RNA expression of intestinal epithelial tight junction protein (ZO1, CLAUDIN1, and CDH1), and the RNA expression of major intestinal inflammatory factors in CD (IL-1ß, IL-6, and TNFα, p < 0.001 for all) were improved significantly. Moreover, hUC-MSCs could attenuate the polarization of M1 macrophage induced from THP1, thereby decreasing the mRNA expression of IL-1ß, IL-6, and TNFα significantly (p < 0.05 for all). TSG-6 expression was evaluated in hUC-MSCs culture supernatant after treatment with TNFα, IFNγ, and LPS for 48 h. And hUC-MSCs could inhibit the phosphorylation of JAK/STAT1 in the intestinal mucosa of CD patients. INTERPRETATION: hUC-MSCs transplantation alleviated TNBS-induced colitis in rats. In this pilot clinical study, preliminary data suggested that this approach to administering hUC-MSCs might have potential for clinical efficacy and manageable safety in treating refractory CD, potentially providing hope for better outcomes. No serious adverse events were observed. FUNDING: This work was funded by General Program of National Natural Science Foundation of China (Grant No. 82270639), the Scientific research project of Shanghai Municipal Health Committee (Grant No. 202240001), Specialty Feature Construction Project of Shanghai Pudong New Area Health Commission (Grant No. PWZzb2022-05), Shanghai East Hospital Youth Research and Cultivation Foundation program (Grant No. DFPY2022015), Peak Disciplines (Type IV) of Institutions of Higher Learning in Shanghai, Technology Development Project of Pudong Science, Technology and Economic Commission of Shanghai (Grant No. PKJ2021-Y08), Key Disciplines Group Construction Project of Shanghai Pudong New Area Health Commission (Grant No. PWZxq2022-06), Medical discipline Construction Project of Pudong Health Committee of Shanghai (Grant No. PWYgf2021-02) and National Natural Science Foundation of China (Grant No. 82300604).

Cutaneous Crohn disease presenting as "knife-edged" ulcers: a case report.

BACKGROUND: CCD presents as non-caseating granulomas within the skin at a site distant from the GI tract. CCD is a debilitating extraintestinal sequela of CD that can sometimes precede its GI manifestations. In the absence of GI symptoms, the histopathologic and clinical features of CCD can present as a variety of inflammatory skin conditions that can range from ruptured follicle-associated granulomas to cutaneous ulcerations. While a variety of therapeutic options for patients with CCD and concurrent luminal CD have been described in the literature, there is no standard treatment algorithm for the management of refractory CCD with limited or covert GI involvement. CASE REPORT: The authors discuss the case of a 33-year-old female who presented to the wound care clinic with multiple "knife-edged" cutaneous ulcerations involving the intertriginous spaces, found to be consistent with CCD. Her original cutaneous symptoms and diagnosis manifested with minimal GI involvement and responded to IVIG treatment. CONCLUSIONS: This case supports the inclusion of CCD in the differential diagnosis in patients with knife-edged granulomatous skin lesions in intertriginous locations. This clinical condition may present in the setting of no or limited GI symptoms. The management of CCD and a proposed treatment algorithm are also presented.