Severity Of Mucosal Inflammation Research Articles

Characterization of cytotoxic Citrobacter braakii isolated from human stomach.

Citrobacter braakii (C. braakii) is an anaerobic, gram-negative bacterium that has been isolated from the environment, food, and humans. Infection by C. braakii has been associated with acute mucosal inflammation in the intestine, respiratory tract, and urinary tract. However, the pathogenesis of C. braakii in the gastric mucosa has not yet been clarified. In this study, the bacterium was detected in 35.5% (61/172) of patients with chronic gastritis (CG) and was closely associated with the severity of mucosal inflammation. Citrobacter braakii P1 isolated from a patient with CG exhibited urease activity and acid resistance. It contained multiple secretion systems, including a complete type I secretion system (T1SS), T5aSS and T6SS. We then predicted the potential pilus-related adhesins. Citrobacter braakii P1 diffusely adhered to AGS cells and significantly increased lactate dehydrogenase (LDH) release; the adhesion rate and LDH release were much lower in HEp-2 cells. Strain P1 also induced markedly increased mRNA and protein expression of IL-8 and TNF-α in AGS cells, and the fold increase was much higher than that in HEp-2 cells. Our results demonstrate proinflammatory and cytotoxic role of C. braakii in gastric epithelial cells, indicating the bacterium is potentially involved in inducing gastric mucosa inflammation.

Modulation of Indoleamine 2,3-Dioxygenase 1 During Inflammatory Bowel Disease Activity in Humans and Mice.

Indoleamine 2,3 dioxygenase-1 (IDO1), a key enzyme in tryptophan metabolism, is strongly up-regulated both in human inflammatory bowel disease (IBD) and animal models of colitis, however its role in the pathogenesis is still controversial. In this study, we investigated IDO1 expression and activity in a mouse model of DSS-induced chronic colitis as well as in colon biopsies and sera from IBD patients. Chronic colitis was induced in mice through the oral administration of dextran sodium sulfate (DSS), and IDO1 activity was induced by i.p. treatment with N-acetyl serotonin (NAS). IDO1 expression and catalytic activity (measured as Kyn/Trp ratio) was evaluated in sera and tissue samples collected from mice and 93 IBD patients under immunotherapy with Vedolizumab (VDZ) or Ustekinumab (UST). Strong up-regulation of IDO1 was found in colons of mice with acute colitis, which follows disease activity. Enhanced IDO1 activity by NAS treatment protects the intestinal mucosa during the recovery phase of chronic colitis. In IBD patients, IDO1 expression and activity correlate with the severity of mucosal inflammation with inflamed regions showing higher IDO1 expression compared to non-inflamed regions within the same patient. Endoscopic response to VDZ/UST treatment is associated with decreased expression of IDO1. This is the first study demonstrating immunomodulatory activity of IDO1 in a chronic mouse model of DSS-induced colitis. As its expression and catalytic activity correlate with the grade of mucosal inflammation and treatment response, IDO1 could represent a promising biomarker for disease severity and treatment monitoring in IBD.

Role of Nox4 in Mitigating Inflammation and Fibrosis in Dextran Sulfate Sodium–Induced Colitis

Fibrosis development in ulcerative colitis is associated directly with the severity of mucosal inflammation, which increases the risk of colorectal cancer. The transforming growth factor-β (TGF-β) signaling pathway is an important source of tissue fibrogenesis, which is stimulated directly by reactive oxygen species produced from nicotinamide adenine dinucleotide phosphate oxidases (NOX). Among members of the NOX family, NOX4 expression is up-regulated in patients with fibrostenotic Crohn's disease (CD) and in dextran sulfate sodium (DSS)-induced murine colitis. The aim of this study was to determine whether NOX4 plays a role in fibrogenesis during inflammation in the colon using a mouse model. Acute and recovery models of colonic inflammation were performed by DSS administration to newly generated Nox4-/- mice. Pathologic analysis of colon tissues was performed, including detection of immune cells, proliferation, and fibrotic and inflammatory markers. RNA sequencing was performed to detect differentially expressed genes between Nox4-/- and wild-type mice in both the untreated and DSS-treated conditions, followed by functional enrichment analysis to explore the molecular mechanisms contributing to pathologic differences during DSS-induced colitis and after recovery. Nox4-/- mice showed increased endogenous TGF-β signaling in the colon, increased reactive oxygen species levels, intensive inflammation, and an increased fibrotic region after DSS treatment compared with wild-type mice. Bulk RNA sequencing confirmed involvement of canonical TGF-β signaling in fibrogenesis of the DSS-induced colitis model. Up-regulation of TGF-β signaling affects collagen activation and T-cell lineage commitment, increasing the susceptibility for inflammation. Nox4 protects against injury and plays a crucial role in fibrogenesis in DSS-induced colitis through canonical TGF-β signaling regulation, highlighting a new treatment target.

Correlation of Helicobacter pylori virulence genotype & severity of mucosal inflammation in gastric biopsies from two geographically diverse regions in India.

H. pylori-associated gastritis in patients from the high-altitude area of Ladakh showed severe gastritis, mucosal nodularity, atrophy, and cancer in comparison to those from North India. This study served to analyze if differences in the H. pylori virulence genotypes decide the extent of gastric mucosal inflammation. Fifty gastric biopsies each from patients with H. pylori-associated gastritis from Ladakh and a tertiary care center in North India were included. The presence of H. pylori strain was confirmed with Warthin starry stain and polymerase chain amplification of the H. pylori-specific 16S rRNA. The cagA, vacA s1, s2, and m1, m2 alleles, and dupA virulence genotypes were studied in all archival samples, followed by their histological correlations. cagA (P 0.009) and vacAs1 m1 (P 0.009) genes were distinctly more in H. pylori strains colonizing the biopsies of North Indian patients. In contrast, the cagA -ve vacAs2 m2 strains were significantly more in H. pylori strain colonizing the biopsies from Ladakhi patients. dupA genotype was almost similarly present in strains from both regions. Among these, only cagA and dupA virulence genes were associated with severe mucosal neutrophilic activity and deep infiltration of H. pylori strains in North Indian patients. Differences in virulence genotypes of H. pylori in gastric biopsies from North Indian and Ladakhi patients were found not significant in deciding the severity of H. pylori-associated gastritis.

DOP15 Fluorescent labelled vedolizumab for real-time visualization and quantification of local drug distribution and pharmacodynamics in Inflammatory Bowel Diseases during endoscopy

Abstract Background Vedolizumab is a monoclonal antibody which blocks integrin α4β7 inhibiting trafficking of T-lymphocytes into the gut. Unfortunately, up to 60% of vedolizumab patients experience non-response. The mechanism of action of vedolizumab is not elucidated, predictors of response are unknown and data for local drug distribution in the gut are lacking. In this clinical trial, we investigated the feasibility of assessing local distribution of fluorescently labelled vedolizumab in the gut mucosa of inflammatory bowel diseases (IBD) patients to finally enable prediction of therapy response in individual patients. Methods Vedolizumab (Entyvio, Takeda Pharma) was labelled to IRDye 800CW under cGMP conditions to yield clinical grade vedolizumab-800CW. In this dose-escalation trial, vedolizumab naïve IBD patients and IBD patients treated with vedolizumab for at least 14 weeks were included. Patients received an intravenous dose of fluorescently labelled vedolizumab of either 0 mg, 4.5 mg, 15 mg or 15 mg + 75 mg unlabelled vedolizumab 3 days prior colonoscopy. In vivo fluorescence imaging was assessed by fibre-based wide-field fluorescence molecular endoscopy (FME) and quantified by spectroscopy in healthy, mildly inflamed and severely inflamed tissue. All assessed tissue was biopsied for ex vivo examination of the fluorescent signal, fluorescence microscopy and spectroscopy. Results Up to submission 34 patients completed tracer injection and FME. An interim analysis was performed after 20 patients (5 in each dose group), which showed in severely inflamed tissue an 8 fold higher fluorescent signal in the 15 mg dose group (0.049 Q*μfa,x [mm-1]) compared to the control group (0.006 μfa,x [mm-1]) (p<0.05). Furthermore, the fluorescent signal within the 15 mg dose group was also 2.5 fold higher compared to healthy tissue (0.019 Q*μfa,x [mm-1]) (p<0.05).The addition of unlabelled vedolizumab gave similar results to the 15 mg group (p>0.99), suggesting that the drug target was still not saturated. The optimal dosage group of 15 mg was expanded up to 18 IBD patients, amongst them 6 IBD patients after 14 weeks of treatment regimen. Fluorescence microscopy showed clustering of fluorescent signals especially in inflamed mucosa. Additional experiments to detect vedolizumab target cells are ongoing. Conclusion In vivo visualization of fluorescent vedolizumab revealed a clear dose-dependent correlation between mucosal drug concentrations and the severity of mucosal inflammation. Fluorescence molecular endoscopy is a promising novel tool to get insight in drug distribution in IBD, detect target cells, assess target engagement and possibly predict therapy response in individual patients.

The Nonsteroidal Anti-Inflammatory Drug Ketorolac Alters the Small Intestinal Microbiota and Bile Acids Without Inducing Intestinal Damage or Delaying Peristalsis in the Rat.

Background: Nonsteroidal anti-inflammatory drugs (NSAIDs) induce significant damage to the small intestine, which is accompanied by changes in intestinal bacteria (dysbiosis) and bile acids. However, it is still a question of debate whether besides mucosal inflammation also other factors, such as direct antibacterial effects or delayed peristalsis, contribute to NSAID-induced dysbiosis. Here we aimed to assess whether ketorolac, an NSAID lacking direct effects on gut bacteria, has any significant impact on intestinal microbiota and bile acids in the absence of mucosal inflammation. We also addressed the possibility that ketorolac-induced bacterial and bile acid alterations are due to a delay in gastrointestinal (GI) transit. Methods: Vehicle or ketorolac (1, 3 and 10 mg/kg) were given to rats by oral gavage once daily for four weeks, and the severity of mucosal inflammation was evaluated macroscopically, histologically, and by measuring the levels of inflammatory proteins and claudin-1 in the distal jejunal tissue. The luminal amount of bile acids was measured by liquid chromatography-tandem mass spectrometry, whereas the composition of microbiota by sequencing of bacterial 16S rRNA. GI transit was assessed by the charcoal meal method. Results: Ketorolac up to 3 mg/kg did not cause any signs of mucosal damage to the small intestine. However, 3 mg/kg of ketorolac induced dysbiosis, which was characterized by a loss of families belonging to Firmicutes (Paenibacillaceae, Clostridiales Family XIII, Christensenellaceae) and bloom of Enterobacteriaceae. Ketorolac also changed the composition of small intestinal bile by decreasing the concentration of conjugated bile acids and by increasing the amount of hyodeoxycholic acid (HDCA). The level of conjugated bile acids correlated negatively with the abundance of Erysipelotrichaceae, Ruminococcaceae, Clostridiaceae 1, Muribaculaceae, Bacteroidaceae, Burkholderiaceae and Bifidobacteriaceae. Ketorolac, under the present experimental conditions, did not change the GI transit. Conclusion: This is the first demonstration that low-dose ketorolac disturbed the delicate balance between small intestinal bacteria and bile acids, despite having no significant effect on intestinal mucosal integrity and peristalsis. Other, yet unidentified, factors may contribute to ketorolac-induced dysbiosis and bile dysmetabolism.

Budesonide treatment for microscopic colitis from immune checkpoint inhibitors

BackgroundImmune checkpoint inhibitors (CPIs) are effective against a variety of malignancies but can be limited by inflammatory toxicities such as enterocolitis. Enterocolitis is typically treated with systemically active glucocorticoids. Endoscopy can stratify patients by the severity of mucosal inflammation, including identifying patients with colitis in the absence of visible mucosal changes: microscopic colitis. Whether patients with CPI microscopic colitis could be managed differently from colitis with more severe mucosal involvement is unclear. The objective of this study was to describe outcomes in CPI microscopic colitis focusing on the response to first line treatment with budesonide.MethodsWe evaluated data from a retrospective cohort from a single-center large academic hospital. The participants were all adult patients evaluated by endoscopy for suspected CPI enterocolitis between 3/2017 and 3/2019. The exposures were: Mayo Endoscopic Score (range 0–3). The subset was: oral budesonide, maximum dose 12 mg daily, administered minimum of 5 weeks. The main outcomes and measures were: Primary: time from first CPI exposure to first glucocorticoid use; use of systemic glucocorticoids; time from symptom onset to resolution; continuation of CPI therapy; number of additional CPI infusions received. Secondary: admissions for symptom control; novel irAE development; need for second-line immunosuppression; oncologic outcomes.ResultsWe identified 38 patients with biopsy confirmed CPI enterocolitis, 13 in the microscopic colitis cohort, and 25 in the non-microscopic colitis cohort. Budesonide use was higher in the microscopic colitis cohort (12/13 vs 3/25, p < 0.001), and systemic glucocorticoid use was higher in non-microscopic colitis (22/25 vs. 3/13, p < 0.001). Time from symptom onset to resolution did not differ. Microscopic colitis patients more frequently remained on CPI after developing (entero)colitis (76.9% vs 16.0%, p < 0.001). Microscopic colitis patients tolerating further CPI received, on average, 4.2 CPI infusions more than non-microscopic colitis patients tolerating CPI (5.8 vs 1.6, p = 0.03). Microscopic colitis was associated with increased time-to-treatment-failure (HR 0.30, 95% CI 0.14–0.66) and progression-free survival (HR 0.22, 95% CI 0.07–0.70).ConclusionsGastrointestinal mucosal inflammation without visible mucosal injury is a distinct, prevalent CPI enterocolitis subset that can be diagnosed by endoscopy. First-line budesonide appears effective in controlling “microscopic colitis” symptoms and prolonging immunotherapy duration. These findings present a compelling rationale for routine endoscopic evaluation of suspected CPI enterocolitis and suggest an alternative glucocorticoid-sparing treatment strategy for a subset of such patients.

Obestatin/Ghrelin Ratio as a New Activity Index in Ulcerative Colitis

Background and Aim: Ulcerative colitis (UC) is an immune-mediated systemic inflammatory process that destroys the intestinal mucosa. Ghrelin, an appetite-regulatory hormone, has anti-inflammatory effects including a decrease in circulating cytokines. Some reports demonstrated a strong relationship between the serum ghrelin level and the severity of mucosal inflammation in the gastrointestinal tract. The aim is to investigate serum levels and colonic mucosal mRNA expression of ghrelin, obestatin, and obestatin/ghrelin ratio in patients with UC and to determine their potential as markers for UC disease activity. Patients and Methods: seventy-five outpatients with UC and 45 age- and sex-matched healthy volunteers were enrolled in this study after written conscious consent and approval by the Institutional Review Board of Mansoura University. UC was diagnosed by conventional clinical, radiological, endoscopic, and histopathological criteria. Serum ghrelin, obestatin levels, and their mucosal mRNA expression were measured by ELISA kits and a real-time quantitative reverse transcriptase polymerase chain reaction according to the manufacturer’s protocols. Results: Serum levels and mucosal mRNA expression of ghrelin were significantly higher in patients with active UC than patients in remission p˂0.0001). Obestatin/ghrelin ratio was significantly lower in patients with active UC (0.26±0.08) than those in remission (0.523±0.16; p˂0.0001). Obestatin/ghrelin ratio was negatively and significantly correlated with inflammation and endoscopic scores, colitis activity index, serum ghrelin level, and its mucosal mRNA expression (p˂0.05). Conclusion: obestatin/ghrelin ratio might be a reliable surrogate non-invasive marker of disease activity in UC with significantly high sensitivity, specificity, predictive values, and diagnostic accuracy.

Stimulator of Interferon Genes in Classical Dendritic Cells Controls Mucosal Th17 Responses to Cyclic Dinucleotides for Host Defenses Against Microbial Infections in Gut.

Cyclic dinucleotides are bacterial signal transducers that bind to host intracellular protein, stimulator of interferon genes (STING) encoded by Tmem173. In this study, we demonstrate that STING triggers adaptive immune responses that control Th17 differentiation. Cyclic dinucleotides recognition enables classical dendritic cells (cDCs) that predominantly express CD103 to induce Th17 lymphocytes in an IL-6/IL-1β-dependent manner in gut. STING expression in human lamina propria is associated with the severity of mucosal inflammation and clinical disease activity in patients with Crohn’s disease. Mice deficient in Tmem173 fail to mount Th17 responses to cyclic dinucleotides or prevent immune evasion of enteroinvasive pathogens. In summary, STING in mucosal cDCs controls Th17 subspecification that is essential for host defenses against microbial infection in gut-associated immune system.

Factors associated with mucosal healing in patients with ulcerative colitis in clinical remission.

Mucosal healing (MH) has been associated with improved outcomes in ulcerative colitis but factors associated with MH are not well defined. Consecutive patients with ulcerative colitis in clinical remission (Mayo symptomatic subscore = 0) who had at least 1 colonoscopy since diagnosis from 6 centers were included. For patients who had at least 2 colonoscopies during follow-up, each colonoscopy was reviewed to define whether they had early MH (Mayo endoscopic subscore reduced to 0 within 3 yr of clinical remission). Factors associated with MH and early MH were determined using logistic regression. Two hundred thirty-seven patients with ulcerative colitis (mean age 50.39 ± 14.10 yr; 56.5% male) were included. Independent factors for MH were clinical remission >3 years (odds ratio [OR] 4.0; 95% confidence interval [CI], 1.2-13.1), mild/moderate mucosal inflammation (OR 3.3; 95% CI, 1.3-8.5), and immunosuppressant use (OR 4.6; 95% CI, 1.5-14.6). Among patients who had ≥2 of above factors, 74% achieved MH, whereas only 39% with <2 factors achieved MH (P < 0.001). Of patients in clinical remission <1 year, 1 to 3 years and >3 years, 30%, 45.9%, and 62.9% achieved MH, respectively. Immunosuppressant therapy was associated with early MH (P = 0.025). In multivariate analysis, patients with previous mild inflammation were more likely to achieve early MH than those with moderate/severe inflammation (OR 2.8; 95% CI, 1.2-6.2). A longer disease remission, previous less severe mucosal inflammation, and immunosuppressant use are associated with MH. Severity of mucosal inflammation and use of immunosuppressant are also associated with early MH.

Rectocolite hémorragique : conduite diagnostique et prise en charge thérapeutique

Ulcerative colitis (UC) is a chronic inflammatory bowel disease limited to the mucosa and affecting the rectum and the colon continuously. Salicylates are the first line treatment for moderate forms. Corticosteroids are used to induce remission, but are not given as maintenance therapy. Thiopurines are indicated as maintenance therapy in case of failure of salicylates or cortico-dependence. Anti TNF alpha are indicated in cortico-resistant severe flares or if cortico- dependence. Vedolizumab (anti-integrin) is the first non anti-TNF alpha biotherapy available for the treatment of UC. Severe acute colitis is a medical emergency; diagnosis is based on Lichtiger score. An emergency colectomy for severe acute colitis is indicated in cases of surgical complication or resistance to medical therapy. UC patients with extension beyond splenic flexure are at risk of colorectal cancer, increasing with the duration of the disease, severity of mucosal inflammation, family history of colorectal cancer, and the existence of sclerosing cholangitis. Annual surveillance colonoscopy is required in patients with sclerosing cholangitis regardless of the extension of their UC.

Anti-inflammatory effect of Moringa oleifera Lam. seeds on acetic acid-induced acute colitis in rats.

Anti-inflammatory, immuno-modulatory, and antioxidant properties of Moringa oleifera Lam. suggest that it might have beneficial effects on colitis. The present study was performed to investigate the anticolitis effect of Moringa oleifera seeds hydro-alcoholic extract (MSHE) and its chloroform fraction (MCF) on acetic acid-induced colitis in rats. Both MSHE and MCF with three increasing doses (50, 100, and 200 mg/kg) were administered orally to separate groups of male Wistar rats, 2 h before ulcer induction (using acetic acid 4%) and continued for 5 days. Prednisolone (4 mg/kg) and normal saline (1 ml/kg) were used in reference and control groups, respectively. All rats were sacrificed 24 h after the last dose (at day 6) and tissue injuries were assessed macroscopically and pathologically. Extracts with three doses mentioned before were effective to reduce weight of distal colon (8 cm) as a marker for inflammation and tissue edema. Three doses of MSHE and two greater doses of MCF (100 and 200 mg/kg) were effective to reduce ulcer severity, area, and index as well as mucosal inflammation severity and extent, crypt damage, invasion involvement, total colitis index, and MPO activity compared with controls. MCF (50 mg/kg) was not significantly effective in reducing evaluated parameters of colitis compared with controls. It is concluded that MSHE and MCF were both effective to treat experimental colitis and this might be attributed to their similar major components, biophenols and flavonoids. Since the efficacy was evident even in low doses of MSHE, presence of active constituents with high potency in seeds is persuasive.

Probiotics improve survival of septic rats by suppressing conditioned pathogens in ascites

To investigate the benefits of probiotics treatment in septic rats. The septic rats were induced by cecal ligation and puncture. The animals of control, septic model and probiotics treated groups were treated with vehicle and mixed probiotics, respectively. The mixture of probiotics included Bifidobacterium longum, Lactobacillus bulgaricus and Streptococcus thermophilus. We observed the survival of septic rats using different amounts of mixed probiotics. We also detected the bacterial population in ascites and blood of experimental sepsis using cultivation and real-time polymerase chain reaction. The severity of mucosal inflammation in colonic tissues was determined. Probiotics treatment improved survival of the rats significantly and this effect was dose dependent. The survival rate was 30% for vehicle-treated septic model group. However, 1 and 1/4 doses of probiotics treatment increased survival rate significantly compared with septic model group (80% and 55% vs 30%, P < 0.05). The total viable counts of bacteria in ascites decreased significantly in probiotics treated group compared with septic model group (5.20 ± 0.57 vs 9.81 ± 0.67, P < 0.05). The total positive rate of hemoculture decreased significantly in probiotics treated group compared with septic model group (33.3% vs 100.0%, P < 0.05). The population of Escherichia coli and Staphylococcus aureus in ascites of probiotics treated group were decreased significantly compared with that of septic model group (3.93 ± 0.73 vs 8.80 ± 0.83, P < 0.05; 2.80 ± 1.04 vs 5.39 ± 1.21, P < 0.05). With probiotics treatment, there was a decrease in the scores of inflammatory cell infiltration into the intestinal mucosa in septic animals (1.50 ± 0.25 vs 2.88 ± 0.14, P < 0.01). Escherichia coli and Staphylococcus aureus may be primary pathogens in septic rats. Probiotics improve survival of septic rats by suppressing these conditioned pathogens.

Faecal Calprotectin as Reliable Non-invasive Marker to Assess the Severity of Mucosal Inflammation in Patients with Ulcerative Colitis

Background and study aim: We aimed to evaluate the validity and accuracy of the faecal calprotectin in differentiating patients with IBD from those with IBS and in the assessment of the severity of intestinal mucosal inflammation in patients with ulcerative colitis (UC) which may facilitate in the prognosis and follow. Patients and Methods: We studied 60 Patients who came to endoscopy unit with lower gastroenterological symptoms. Patients with history of infections, malignancy, gastrointestinal surgery, pregnancy, alcohol abuse or taking nonsteroidal anti-inflammatory drugs were excluded from study. All patients subjected to thorough medical history, simple clinical colitis activity index was determined with a score ˃ 4 indicate active UC, complete blood picture, liver, kidney function tests, ESR, CRP, ANCA were done, a stool sample for FC levels determined by a highly sensitive enzymelinked immunosorbent assay and total colonoscopy with histological examination of intestinal mucosa biopsy were done. The patients divided into 2 groups. Group A: patients with UC, group B: patients with manifestation of irritable bowel syndrome as a control group. Results: There was a high significant difference between individuals with no pathological activity and other degree of mucosal inflammation as regard simple clinical colitis activity index, endoscopic appearance and faecal calprotectin (p = 0.000). The sensitivity, specificity, positive predictive value and negative predictive value of faecal calprotectin in diagnosis of UC were 93.5%, 89.7%, 90.6%, and 92.9% respectively. The positive predictive value and negative predictive value of simple clinical colitis activity index for diagnosis of UC were 76.5% and 80.8% respectively. The positive predictive value and negative predictive value of endoscopic appearance for diagnosis of UC were 100%, and 85.3% respectively. There was a high significant difference and positive correlation between faecal calprotectin, score of colonic pathological activity, endoscopic appearance and simple clinical colitis activity index. Conclusion: Faecal calprotectin is highly useful for the diagnosis and disease monitoring of patients with UC as it is easy, non invasive, reliable tool

Mucosal Healing and Clinical Remission in Inflammatory Bowel Diseases

I read with interest the article by Baars et al. These authors studied the prevalence and severity of mucosal inflammation in patients with ulcerative colitis (UC) and Crohn’s disease (CD) while in clinical remission. In addition, during follow-up they studied whether their findings impacted therapeutic strategies and disease course. Approximately one-third of patients had an intact mucosa at first endoscopy while one-third had endoscopic and histologic lesions and another third only histologic lesions. In most patients, in the authors’ centers, therapeutic strategy was not changed after endoscopy. Although in the long term mucosal inflammation fluctuated among the different groups (with and without initial lesions), the same was not associated with more frequent clinical relapses or stricture formation/ need for surgery. There were essentially no differences between patients with CD and UC...

Mo1557 DNA Methylation in Gastric Mucosae is Associated With the Severity of Mucosal Inflammation Involving the Risk of Diffuse-Type Gastric Cancer

Background and aims: Aberrant DNA methylation observed in the atrophic gastritis with the past infection of Helicobacter pylori (H. pylori) is associated with the risk of gastric cancer, mainly intestinal-type. In contrast, DNA methylation in gastric mucosae at risk of diffusetype gastric cancer is not fully known. We have found that the subjects with severe gastric mucosal inflammation identified by serum markers have higher risk of the development of diffuse-type gastric cancer. Thosewho showedH. pylori antibody titer >500U/mL, pepsinogen (PG) II >30 ng/mL, or PG I >70 ng/mL and PG I/II ratio 500 U/mL) and high levels of PG II (>30 ng/mL). The methylation levels were also severely altered in the subjects with serum PG I >70 ng/mL and PG I/II ratio <3.0. Conclusions: DNA methylation in gastric mucosae was closely associated with the severity of inflammation identified by serum H. pylori antibody or PGs. These results suggest that DNAmethylation works to some extent in the occurrence of diffusetype gastric cancer resulting from severe active inflammation induced by H. pylori infection.

505 Clinical Significance of Endocytoscopic Findings in Ulcerative Colitis

Clinical Significance of Endocytoscopic Findings in Ulcerative Colitis Kayoko Matsushima*, Hajime Isomoto, Ryohei Uehara, Junya Shiota, Yuko Akazawa, Naoyuki Yamaguchi, Ken Ohnita, Toshiyuki Nakayama, Tomayoshi Hayashi, Fuminao Takeshima, Kazuhiko Nakao Gastroenterology and Hepatology, Nagasaki University, Nagasaki, Japan; Pathology, Nagasaki University, Nagasaki, Japan Aim: To explore the association of endocytoscopic and magnified endoscopic findings with disease activity and relapse in patients with ulcerative colitis (UC). Methods: Forty mild to moderate UC patients underwent magnifying colonoscopy with crystal violet (CV) staining and/or NBI, and 24 patients underwent endocytoscopy (Olympus). Each case was classified into Matts’ grade 1 (n 14) or grade 2 (n 26) by Matts’ endoscopic grading. Those magnified endoscopic observation was specially referenced to microvascular abnormality and microsurface structures changes of glandular pits, and was compared to pathological characteristics including disease activity and extension, clinical course and relapse within 6 months. Results: On NBI, microvascular abnormalities including irregular, distorted or dilated microvessels and prominent lymphoid follicles were identified in 50% of all patients. Of note, 63.6% of patients with abnormal vessels and only 11.2% of patients with normal vessels had relapse (p 0.05). We classified CV-magnified chromoendoscopic findings into 5 grades as follows: CV-Grade1(G1); normal-appearing oval pits, CV-G2; irregular arrangement of round to oval pits, CV-G3; opening of intervening round to oval pits, CV-G4; irregular dilatation of pits, CV-G5; disappearance of pits. CV-grades of Matts’ grade 2 patients showed more severe than Matts’ grade 1 patients (CV-G4/5; 65.4% vs 0%, p 0.0001). In pathological findings, CV-G4/5 patients were associated with a higher incidence of inflammatory cells infiltration than CV-G13 (86.7% vs 26.1%, p 0.001). In the similar way, crypt abscess was shown in 73.3% vs 26.1% (p 0.01). Goblet cell depletion was shown in 86.7% vs 34.8%(p 0.005). Of clinical importance, 63.6% of CV-G4/5 patients experienced relapse within 6 months, whilst only 20% were experienced in CV-G13 patients (p 0.05). Endocytoscopy could detect grandular infiltration of cell components in accordance with histological features of severe inflammatory cell infiltration and crypt abscess. We classified endocytoscopic (EC) findings into 5 grades as follows: EC-G1; normal-appearing round pits with nominal inter-glandular cell components, EC-G2; oval pits with sparse inter-glandular cell components, ECG3; increased inter-glandular cell components, EC-G4; irregular dilation of pits with/without intra-glandular cell components, EC-G5; disruption or disappearance of pits. Each grade of EC findings was well matched for the each grade of CV-magnified endoscopic classification. Furthermore, the features of EC findings were remarkably similar to those pathological findings. Conclusion: The chromomagnifying endoscopic observation with CV could be rather predictive with respect to the disease activity and relapse in UC. Endocytoscopy seems to be promising to conjecture the severity of mucosal inflammation as well as disease relapse and activity.

Correlation of Two Capsule Endoscopy Scoring Systems with Fecal Calprotectin: Does It Really Matter?

In the absence of a gold standard test, the diagnosis of isolated small bowel Crohn’s disease (CD) is often challenging. Clinical symptoms and signs are often nonspecific and may not correlate well with disease activity. We now know that barium small bowel imaging has limited value in evaluating mucosal lesions. Newer imaging modalities such as computed tomographic enterography (CTE) and magnetic resonance enterography (MRE) have higher sensitivity for detecting transmural inflammation [1], but they have limited value in evaluating isolated mucosal inflammation. Capsule endoscopy (CE), on the other hand, is an excellent, relatively non-invasive modality for direct mucosal visualization and thus can detect more subtle inflammatory change. As a result, CE is a useful tool for evaluating ulcerating diseases of the small bowel and may potentially aid in assessing disease activity and extent, as well as monitoring mucosal healing [2, 3]. However, one of the limitations has been the lack of an accurate and reproducible standardized scoring system that objectively assesses the severity of small bowel inflammation. In 2008, Gal et al. [4] published a simple, validated Capsule Endoscopy Crohn’s Disease Activity Index (CECDAI). This scoring index evaluates three parameters of small bowel pathology in CD: inflammation, extent of disease and presence of a stricture. All three parameters are calculated separately for the proximal and distal segments of the small bowel. This index has a high overall correlation (range 0.8–0.93; p 0.001) and agreement (0.867). Later, Gralnek et al. [5] developed the Lewis score (LS), which is based on villous edema, ulceration and stenosis detected on CE. An excellent inter-observer agreement for the global assessment of mucosal disease severity (84–86%) was noted, although the LS has not been prospectively validated. Both of these scoring indices potentially can be used for objectively measuring the degree of inflammatory activity. They may also be of benefit in assessing the degree of mucosal healing, which appears to be an important goal in the management of CD. Though these scoring indices are a step forward, there are important limitations. These indices were developed initially to standardize capsule reporting, but their use as a clinical tool is not yet clear and more prospective validation studies are needed. Simply stated, we do not know how accurately they measure the degree of mucosal inflammation. In addition, they have no discriminatory ability in differentiating CD from NSAID enteropathy, celiac disease, and/or ischemia. Other non-invasive methods have been studied to assess and quantify small bowel inflammation. One promising method is measurement of fecal calprotectin (FC). FC is a human protein, released into feces from activated granulocytes and inflamed epithelia [6]. The amount of FC in feces is proportional to the granulocyte migration to the gastrointestinal mucosa. Unlike the CE scoring indices, several studies have shown an excellent correlation of FC with the severity of mucosal inflammation [7, 8]. There are many studies that confirm that FC can differentiate inflammatory from non-inflammatory gastrointestinal disorders, including small bowel inflammation [8, 9]. Therefore, many consider FC a ‘‘gold standard,’’ reliable and highly specific marker of inflammation. So one might wonder if there is a correlation between FC and the current CE scoring indices and how it matters in measuring inflammation. S. R. Gurudu (&) J. A. Leighton Division of Gastroenterology and Hepatology, Mayo Clinic Arizona, 13400 East Shea Blvd, Scottsdale, AZ 85259, USA e-mail: Gurudu.Suryakanth@mayo.edu

Constitutive TL1A Expression under Colitogenic Conditions Modulates the Severity and Location of Gut Mucosal Inflammation and Induces Fibrostenosis

Intestinal fibrostenosis is a hallmark of severe Crohn's disease and can lead to multiple surgeries. Patients with certain TNFSF15 variants overexpress TL1A. The aim of this study was to determine the effect of TL1A overexpression on intestinal inflammation and the development of fibrostenosis. We assessed the in vivo consequences of constitutive TL1A expression on gut mucosal inflammation and fibrostenosis using two murine models of chronic colitis. In the dextran sodium sulfate (DSS) and adoptive T-cell transfer models, there was proximal migration of colonic inflammation, worsened patchy intestinal inflammation, and long gross intestinal strictures in Tl1a transgenic compared to wild-type littermates. In the DSS model, myeloid- and T-cell-expressing Tl1a transgenic mice had increased T-cell activation markers and interleukin-17 expression compared to wild-type mice. In the T-cell transfer model, Rag1(-/-) mice receiving Tl1a transgenic T cells had increased interferon-γ expression but reduced T-helper 17 cells and IL-17 production. Narrowed ureters with hydronephrosis were found only in the Tl1a transgenic mice in all chronic colitis models. In human translational studies, Crohn's disease patients with higher peripheral TL1A expression also exhibited intestinal fibrostenosis and worsened ileocecal inflammation with relative sparing of rectosigmoid inflammation. These data show that TL1A is an important cytokine that not only modulates the location and severity of mucosal inflammation, but also induces fibrostenosis.

Is sigmoidoscopy sufficient for evaluating inflammatory status of ulcerative colitis patients?

An adequate range of colonic observations for precise evaluation of inflammation in ulcerative colitis (UC) patients has not been reported. Retrospective analysis of 545 colonoscopic examinations of UC patients was carried out. Severity of mucosal inflammation was evaluated using the Mayo score of endoscopic index at each location (rectum, sigmoid colon, descending colon, and the oral side of the splenic flexure) in each patient. The colonic site with maximum inflammation was determined for each patient. Of 545 patients, 319 (59%) had maximum inflammation in the rectum, 79 (14%) in the sigmoid colon, 70 (13%) in the descending colon, and 77 (14%) on the oral side of the splenic flexure. Severe inflammatory activity (Mayo 3) was observed more frequently in patients who had maximum activity in the descending colon or the more proximal portion than those who had this in the rectum or sigmoid colon (42% vs 25%, P<0.0001). The first-attack patients were significantly more frequently found in patients with maximum severity in the descending colon or the oral side of splenic flexure than those with maximum severity in the rectum or sigmoid colon (P=0.016). Moreover, among 134 patients with no inflammation in the rectum and sigmoid colon, 54 (40%) had inflamed mucosa in the descending colon or the more proximal portion. Sigmoidoscopy is not sufficient for evaluating inflammation in UC patients. In particular, colonoscopy is necessary for first-attack patients and patients who have a discrepancy between rectosigmoid observation and symptoms.