Non-cirrhotic portal hypertension in inflammatory bowel disease.

With the increasing incidence and prevalence of inflammatory bowel diseases (IBD), its complications and associated morbidity also continue to rise. One of these is non-cirrhotic portal hypertension. There is an increasing need of recognizing and understanding the pathophysiology of this condition in the clinical setting of IBD, especially in long standing cases. Due to multiple potential factors, patients with IBD appear to be at a higher risk of developing portal hypertension even in the absence of liver cirrhosis. Portal hypertension is usually diagnosed when complications (such as ascites, variceal bleeding) develop, especially when patients have already experienced multiple complications of the disease. Hence, a high level of vigilance for the detection of portal hypertension at an early stage is needed. This review discusses the known epidemiology, clinical characteristics, clinical presentation, modalities of diagnosis and the potential treatments of the different forms of non-cirrhotic portal hypertension associated with IBD. The concomitant presence of portal hypertension can significantly impact the overall clinical picture and disease burden in IBD. Hence, increased awareness of this condition at an early stage might help tailor a comprehensive and individualized therapeutic plan of care for these patients.

Is Ustekinumab Effective in Refractory Crohn's Disease of the Pouch and Chronic Pouchitis? A Systematic Review.

Crohn's disease (CD) of the pouch and chronic pouchitis represent the most common long-term complications of total proctocolectomy and ileal pouch anal anastomosis (IPAA) for refractory ulcerative colitis (UC). These conditions are treated with multiple agents, including antibiotics, immunomodulators, and biologics. Among the latter, ustekinumab is approved for both CD and UC. We performed a systematic review to evaluate the efficacy of this anti-IL12/23 in CD of the pouch and chronic refractory pouchitis. Pubmed, Embase, Ovid, and the Cochrane Controlled Trials Register were searched to identify studies published until August 2020 investigating the use of ustekinumab for these conditions. Eighty-six eligible patients with IPAA-51 with CD of the pouch, 35 with chronic pouchitis-were identified from 2 retrospective studies and 5 case reports. Reported clinical response to ustekinumab was 63 and 85% in chronic pouchitis and CD of the pouch after 4-12 and 4-16 weeks, respectively. Clinical remission was reported in 10% of patients with chronic pouchitis and 27% of patients with CD of the pouch after 8-52 and 4-52 weeks of treatment, respectively. Endoscopic response was reported in 60% and 67% of patients with chronic pouchitis and CD of the pouch after 24-32 and 8-24 weeks of treatment respectively. Small sample sizes and large heterogeneity of therapy protocols/outcome definitions were significant studies limitations. In conclusion, there is a limited and inconclusive body of evidence suggesting that ustekinumab may be a therapeutic option for patients with chronic pouchitis and CD of the pouch refractory to other therapies.

Probiotic-Induced Tolerogenic Dendritic Cells: A Novel Therapy for Inflammatory Bowel Disease?

Inflammatory bowel diseases (IBDs) are immune-mediated, chronic relapsing diseases with a rising prevalence worldwide in both adult and pediatric populations. Treatment options for immune-mediated diseases, including IBDs, are traditional steroids, immunomodulators, and biologics, none of which are capable of inducing long-lasting remission in all patients. Dendritic cells (DCs) play a fundamental role in inducing tolerance and regulating T cells and their tolerogenic functions. Hence, modulation of intestinal mucosal immunity by DCs could provide a novel, additional tool for the treatment of IBD. Recent evidence indicates that probiotic bacteria might impact immunomodulation both in vitro and in vivo by regulating DCs' maturation and producing tolerogenic DCs (tolDCs) which, in turn, might dampen inflammation. In this review, we will discuss this evidence and the mechanisms of action of probiotics and their metabolites in inducing tolDCs in IBDs and some conditions associated with them.

Wireless Capsule Endoscopy for Diagnosis and Management of Post-Operative Recurrence of Crohn's Disease.

Despite aggressive medical therapy, many patients with Crohn's disease require surgical intervention over time. After surgical resection, disease recurrence is common. Ileo-colonoscopy and the Rutgeerts score are commonly used for diagnosis and monitoring of post-operative endoscopic recurrence. The latter is the precursor of clinical recurrence and therefore it impacts prognosis and patient management. However, due to the limited length of bowel assessed by ileo-colonoscopy, this procedure can miss out-of-reach, more proximal lesions in the small bowel. This limitation introduces an important uncertainty when evaluating post-operative relapse by ileo-colonoscopy. In addition, the Rutgeerts score 'per se' bears a number of ambiguities. Here we will discuss the pros and cons of ileo-colonoscopy and other imaging studies including wireless capsule endoscopy to diagnose and manage post-operative recurrence of Crohn's disease. A number of studies provide evidence that wireless capsule endoscopy is a potentially more accurate as well as less invasive and less costly alternative to conventional techniques including ileo-colonoscopy.

Noncanonical NF-κB Signaling Upregulation in Inflammatory Bowel Disease Patients is Associated With Loss of Response to Anti-TNF Agents.

Objectives: Targeting tumor necrosis factor (TNF) with biologic agents, such as infliximab and adalimumab, is a widely used and effective therapeutic strategy in inflammatory bowel disease (IBD). Unfortunately, a significant number of patients fail to respond or lose response over time to these agents. Previous studies have defined multiple complex roles for canonical NF-κB signaling in the pathogenesis of IBD. However, preliminary evidence suggests that the lesser defined noncanonical NF-κB signaling pathway also contributes to disease pathogenesis and response to anti-TNF agents. The objective of this study was to evaluate this hypothesis in Crohn's disease (CD) and ulcerative colitis (UC) patients. Design: A total of 27 subjects with IBD (19 with CD and 8 with UC) and 15 control subjects were tested. Clinical criteria, patient history, and endoscopic disease activity were factors used to categorize patients and define therapeutic response. Biopsy specimens were collected during colonoscopy and expression was determined for 88 target genes known to be associated with noncanonical NF-κB signaling and IBD. Results: Noncanonical NF-κB signaling was significantly upregulated in IBD patients and was associated with increased gastrointestinal inflammation, epithelial cell death, lymphocyte migration, and Nod-like receptor signaling. Furthermore, noncanonical NF-κB signaling was further upregulated in patients unresponsive to anti-TNF agents and was suppressed in responsive patients. MAP3K14, NFKB2, CCL19, CXCL12, and CXCL13 were significantly dysregulated, as were genes that encode pathway regulators, such as CYLD, NLRP12, and BIRC2/3. Conclusion: Our study identifies a previously uncharacterized role for the understudied noncanonical NF-κB signaling pathway in the pathogenesis of IBD and anti-TNF therapy responsiveness. The genes and pathways identified may ultimately prove useful in IBD management and could potentially be used as biomarkers of drug response.

Fecal Lactoferrin Predicts Primary Nonresponse to Biologic Agents in Inflammatory Bowel Disease.

INTRODUCTION: Fecal lactoferrin (FL) is a timely and accurate marker of inflammation in ulcerative colitis (UC) and Crohn's disease (CD). The aim of this study was to verify whether FL can predict primary nonresponse (PNR) to biologic agents during induction. METHODS: Retrospective outcome review in 27 patients (13 with CD and 14 with UC) tested for baseline FL and retested within a week after the first and second induction doses. Clinical/biochemical outcomes were evaluated at end of induction and at follow-up (3-24 months). RESULTS: Compared to baseline, changes of the Harvey-Bradshaw (CD) and Partial Mayo Scoring (UC) indices at end of induction separated responders (18/27 or 67%) from nonresponders (9/17 or 33%). In all patients, the initial FL value at induction decreased compared to baseline, continuing to decrease after the following dose in clinical responders while bouncing back in the others. Models targeting the 2 consecutively decreased FL values or the second FL value compared to baseline or the second FL value compared to the first were able to accurately predict response at end of induction. Follow-up assessment confirmed clinical remission in initial responders (with FL values reduced on the average by 94 ± 10% compared to baseline). CONCLUSIONS: In CD and UC patients during induction with biologic agents, early FL measurements accurately separate clinical responders from those experiencing PNR. The method described here offers several potential advantages over other strategies to assess and manage these patients.

Timely Monitoring of Inflammation by Fecal Lactoferrin Rapidly Predicts Therapeutic Response in Inflammatory Bowel Disease.

BACKGROUND: Fecal lactoferrin (FL) levels may mirror drug-induced changes in inflammation in ulcerative colitis and Crohn disease in a timely way and could be used to assess loss of response (LOR) to biologics. METHODS: This study is a retrospective outcome review in 61 patients on adalimumab, infliximab, or vedolizumab managed in our center and followed for 6 to 24 months. Patients were 1) in clinical remission or 2) were experiencing possible LOR. RESULTS: For group 1, in 71% of 31 patients, FL slowly increased during the therapeutic interval (R2 = 0.769; P < 0.001), thus reflecting increasing inflammation as drug concentrations decreased. In the remaining patients, FL was undetectable throughout the therapeutic interval because of a stronger suppression of inflammation. For group 2, in 30 patients negative for infections, FL levels measured 1 to 3 days after infusion/injection compared to preadministration values either increased (nonresponders)-in these patients the medication was switched to another class; partially decreased (partial responders)-the therapeutic interval was shortened; or were normal throughout (responders)-causes for symptoms unrelated to disease activity were found for all. After FL-based management, 3-month standardized clinical scores were normalized in both partial responders (0.58 ±â€…0.21 vs 0.13 ±â€…0.09; P < 0.001) and nonresponders (0.81 ±â€…0.17 vs 0.12 ±â€…0.08; P < 0.001), and FL levels dropped by up to 99%. CONCLUSIONS: Levels of FL reflect drug-induced changes in mucosal inflammation in a timely way, thus enabling rapid assessment of therapeutic response in patients with ulcerative colitis and with Crohn disease. In patients with suspected LOR, FL levels before and after infusion/injection accurately separated responders, partial responders, and nonresponders. The strategy proposed here is simple, accurate, and easily applicable to clinical practice.

Diagnostic Modality of Clostridioides difficile Infection Predicts Treatment Response and Outcomes in Inflammatory Bowel Disease.

BACKGROUND: Inflammatory bowel disease (IBD) patients are at increased risk of developing Clostridioides difficile infection (CDI). Common methods to diagnose CDI involve a combination of tests including the toxin A/B enzyme immunoassay (Toxin) and toxin gene polymerase chain reaction assay (PCR). Disease outcomes in Toxin+ versus Toxin-PCR+ IBD patients remain unclear. AIMS: This study aimed to examine the response to antibiotics and risk of IBD therapy escalation in Toxin+ versus Toxin-PCR+ patients. METHODS: IBD patients at an academic center with CDI diagnosis based on Toxin+ or Toxin-PCR+ from 2012 to 2017 were identified. Comparisons of response to antibiotics within 30 days and escalation of IBD therapy within 90 days of CDI diagnosis between these two groups were analyzed by Chi-square analysis. Multivariable regression analysis examined factors associated with antibiotic response. RESULTS: Among 92 patients included, 61% had Crohn's disease and 39% had ulcerative colitis. 70% tested Toxin-PCR+. 60% received vancomycin or fidaxomicin to treat CDI. 82% of Toxin+ patients responded to antibiotics compared to 25% of Toxin-PCR+ patients (p < 0.001). 21% of Toxin+ patients required IBD therapy escalation compared to 63% of Toxin-PCR+ patients (p < 0.001). When adjusted for the types of antibiotics used, IBD subtypes, and immunosuppression status, positivity to Toxin (OR 14.85, CI 4.62-47.72) was the most significant predictor of response to antibiotics. CONCLUSIONS: Toxin+ compared to Toxin-PCR+ IBD patients had a significantly higher rate of response to antibiotics and lower chances of requiring IBD therapy escalation. Future outcome studies involving CDI in IBD patients should be stratified by modality of diagnosis.

Fecal Lactoferrin and Other Stool Markers during Normal Pregnancy and in Inflammatory Bowel Diseases: A Prospective Study and Review of the Literature.

INTRODUCTION: Management of inflammatory bowel diseases (IBDs) - both Crohn's disease (CD) and ulcerative colitis (UC) - during pregnancy can be challenging since most monitoring tools available in nonpregnant patients are contraindicated. OBJECTIVES: The aim of the study was to test whether fecal inflammatory markers - specifically fecal lactoferrin - physiologically change during normal pregnancy as a prerequisite to use them to monitor IBD activity during pregnancy. METHODS: Fecal lactoferrin was tested in healthy pregnant and nonpregnant women from the same geographic area and age range (18-40 years) - all negative for clinical gastrointestinal tract inflammation. A retrospective review of fecal lactoferrin levels contrasted with the Simple Endoscopic Score for CD, and the Disease Activity Index for UC was also performed in women with active IBDs within the same age range and geographical area. RESULTS: In 30 nonpregnant subjects, fecal lactoferrin levels were 0.87 ± 1.08 µg/g. In 49 pregnant subjects, levels were 0.59 ± 0.83, 0.87 ± 1.13, and 0.85 ± 1.06 µg/g during the first, second, and third trimester, respectively (p = 0.64), with average levels for the 3 trimesters of 0.81 ± 1.04 µg/g (p = 0.61 compared to nonpregnant subjects). Sequential fecal lactoferrin levels (n = 26) did not differ from one trimester to the other in the individual subjects (p = 0.80). In 45 female IBD patients (27 with CD and 18 with UC), fecal lactoferrin levels were correlated with disease activity as defined by the endoscopic scores: 218, 688, and 1,175 µg/g for CD and 931, 2,088, and 2,509 µg/g for UC, respectively, for mild, moderate, and severe activity. CONCLUSIONS: Fecal lactoferrin levels during normal pregnancy are superimposable to those of nonpregnant women and significantly below levels in women of the same childbearing age with active IBDs. Additional published data - reviewed in this atricle - and our own indicate that fecal lactoferrin and other markers can be potentially used to monitor disease activity in pregnant IBD patients.

Immunomodulation and Generation of Tolerogenic Dendritic Cells by Probiotic Bacteria in Patients with Inflammatory Bowel Disease.

In inflammatory bowel diseases (IBD), the therapeutic benefit and mucosal healing from specific probiotics may relate to the modulation of dendritic cells (DCs). Herein, we assessed the immunomodulatory effects of four probiotic strains including Lactobacillus salivarius, Bifidobacterium bifidum, Bacillus coagulans and Bacillus subtilis natto on the expression of co-stimulatory molecules, cytokine production and gene expression of signal-transducing receptors in DCs from IBD patients. Human monocyte-derived DCs from IBD patients and healthy controls were exposed to four probiotic strains. The expression of co-stimulatory molecules was assessed and supernatants were analyzed for anti-inflammatory cytokines. The gene expression of toll-like receptors (TLRs), IL-12p40 and integrin αvß8 were also analyzed. CD80 and CD86 were induced by most probiotic strains in ulcerative colitis (UC) patients whereas only B. bifidum induced CD80 and CD86 expression in Crohn's disease (CD) patients. IL-10 and TGF-ß production was increased in a dose-independent manner while TLR expression was decreased by all probiotic bacteria except B. bifidum in DCs from UC patients. TLR-4 and TLR-9 expression was significantly downregulated while integrin ß8 was significantly increased in the DCs from CD patients. IL-12p40 expression was only significantly downregulated in DCs from CD patients. Our findings point to the general beneficial effects of probiotics in DC immunomodulation and indicate that probiotic bacteria favorably modulate the expression of co-stimulatory molecules, proinflammatory cytokines and TLRs in DCs from IBD patients.

Low glutamate dehydrogenase levels are associated with colonization in Clostridium difficile PCR-only positive patients with inflammatory bowel disease.

BACKGROUND/AIMS: Clostridioides difficile infection (CDI) remains a diagnostic challenge in patients with inflammatory bowel disease (IBD). We tested novel biomarkers to differentiate CDI from colonization in patients without (CDI-only) and with IBD (IBD-CDI). METHODS: Samples were enzyme immunoassay (EIA)-tested for glutamate dehydrogenase (GDH) and toxin, followed by reflex PCR. Quantitative GDH [(qGDH) - a novel indicator of Clostridium difficile load] and stool lactoferrin were tested at days 0, 3 and 10 during antibiotic treatment. Samples were also analyzed for toxin B cytotoxicity neutralization assay (CNA) and toxigenic culture, gold standards to detect free toxin and virulent bacteria, respectively. RESULTS: Forty-five symptomatic patients (28 CDI-only, 13 with Crohn's disease, 4 with ulcerative colitis) were recruited with 3 sequential samples available for 36 (21 CDI-only, 15 IBD-CDI). Thirty-nine of 45 (87%) cases were toxigenic culture-positive. In the CDI-only group, 78.6% were positive for EIA-toxin, 21.4% were PCR-positive while 82.1% were CNA-positive. In the IBD-CDI group, only one patient (6%) was EIA-toxin positive and 17.6% CNA-positive. The median qGDH level at day 0 was higher in CNA-positive patients compared to CNA-negative patients (1111 vs. 146 ng/g, P = 0.004) and dropped together with lactoferrin from day 0 to 10. CDI eradication improved symptoms in 72.2% of patients with CDI-only. In 60% of patients with IBD-CDI, eradication was ineffective, with symptoms improving in 89% of them after IBD therapy intensification. CONCLUSION: In patients with IBD-CDI, PCR-only positivity might mainly reflect colonization rather than disease. C. difficile load by qGDH correlates with CNA-detected toxin and together with stool lactoferrin might differentiate CDI from colonization in patients with IBD.

The Gut Microbial Profile of Preclinical Crohn's Disease Is Similar to That of Healthy Controls.

BACKGROUND AND AIMS: It is unclear whether microbial dysbiosis plays an etiologic role in Crohn's disease (CD) or is the result of protracted inflammation. Here, we test the hypothesis that dysbiosis predates clinical CD in asymptomatic first-degree relatives (FDRs) of CD patients: normal (FDR1), with borderline inflammation (FDR2), and with frank, very early inflammation (FDR3). METHODS: The gut microbial diversity was tested in ileocecal biopsies through next generation sequencing of the 16S rRNA gene in 10 healthy controls (HCs), 22 patients with active, untreated CD, and 25 FDRs (9 FDR1; 12 FDR2; 4 FDR3). The metagenomic functions of 41 microbiome-related processes were inferred by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis. RESULTS: Compared with HCs, alpha diversity in CD patients was decreased, with an observed decrease in Faecalibacterium prausnitzii and increase in Bacteroides fragilis. In FDRs, microbial diversity was unchanged compared with HCs. In Operational Taxonomic Units and PICRUSt Principal coordinates and component analyses, the ellipse centroid of FDRs was diagonally opposed to that of CD patients, but close to the HC centroid. In both analyses, statistically significant differences in terms of beta diversity were found between CD and HC but not between FDR and HC. CONCLUSIONS: In FDRs (including FDR3-who bear preclinical/biologic onset disease), we found that the microbial profile is remarkably similar to HC. If confirmed in larger studies, this finding suggests that clinical CD-associated dysbiosis could result from the changed microenvironment due to disease evolution over time.

Capturing the Biologic Onset of Inflammatory Bowel Diseases: Impact on Translational and Clinical Science.

While much progress has been made in the last two decades in the treatment and the management of inflammatory bowel diseases (IBD)-both ulcerative colitis (UC) and Crohn's Disease (CD)-as of today these conditions are still diagnosed only after they have become symptomatic. This is a major drawback since by then the inflammatory process has often already caused considerable damage and the disease might have become partially or totally unresponsive to medical therapy. Late diagnosis in IBD is due to the lack of accurate, non-invasive indicators that would allow disease identification during the pre-clinical stage-as it is often done in many other medical conditions. Here, we will discuss what is known about the biologic onset and pre-clinical CD with an emphasis on studies conducted in patients' first degree relatives. We will then review the possible strategies to diagnose IBD very early in time including screening, available disease markers and imaging, and the possible clinical implications of treating these conditions at or close to their biologic onset. Later, we will review the potential impact of conducting translational research in IBD during the pre-clinical stage, especially focusing on the role of the microbiome in disease etiology and pathogenesis. Finally, we will highlight possible future developments in the field and how they can impact IBD management and our scientific knowledge of these conditions.