Sigmoid Biopsies Research Articles

Mo1728 Cytokine and microRNA Expression in Colonic and Ileal Crohn's Disease Is Modified by Drug Therapy in an Ex Vivo Model

Introduction MicroRNAs (miRNA) are short 19–23 nucleotide long strands of RNA which modify post transcriptional gene expression by inhibiting mRNA translation. Studies show there is dysregulation of miRNA expression in IBD but do not take account of factors such as disease activity and drug treatment. The specific function of miRNAs in Crohns Disease (CD) or how they might be utilised is yet to be investigated. We aim to show that mucosal miRNA and mRNA expression in CD is influenced by drugs and has varying effects on the expression in ileum and sigmoid. We use an ex vivo model with active drug to replicate these changes. Method Sigmoid or ileal biopsies from 68 patients with either untreated active CD, inactive CD, or monotherapy with Azathioprine, Infliximab or Adalimumab, as well as normal controls, were snap frozen. RT-qPCR assessed expression of miR31, 155 and 146a and genes CCL18 and SOCS1. Ex vivo model: 6 biopsies were taken from the sigmoid colon of 8 patients with active sigmoid CD, and ileum of 7 patients with active ileal CD with a CDAI of 150 or greater. Biopsies were placed in culture media in separate wells with either no treatment, 5-ASA, 6-TG, Infliximab, or Adalimumab, then incubated at 37 o C. RT-qPCR analysed expression of miRNA and mRNA. Results miR31 and CCL18 expression was raised in active sigmoid CD compared to normal mucosa. miR31 expression was not raised in inactive sigmoid disease compared to normal mucosa, however CCL18 expression was. Only Azathioprine decreased miR31 expression. All treatments reduced CCL18 expression, but Azathioprine reduced it lower than untreated inactive disease. Ileal CD showed no increase of miR31 in active disease. CCL18 is reduced in ileal mucosa of CD compared to normal tissue. Only Adalimumab altered CCL18 expression in ileal CD. The ex vivo model showed all the treatments reduced CCL18 expression in active sigmoid CD. miR31 expression was reduced by 6-TG and Infliximab but not Adalimumab. In ileal CD drugs do not change miR31 or CCL18 expression, except for Adalimumab which increased CCL18 expression. Conclusion CCL18 and miR31 expression is only increased in sigmoid CD, suggesting different immunological pathways in ileal and colonic CD. Thiopurines are more effective at altering expression in colonic disease. Differential effects of anti-TNFs are of significant interest but require further investigation before any clinical significance can be made. Our data sheds new light on mechanisms of action of current therapy and highlights the importance of controlling for medication when analysing miRNA expression. For the first time we show expression profiles can be manipulated in an ex vivo model. This model could be useful in predicting individual treatment response. Disclosure of interest None Declared.

Mo1727 Drug Therapies in Ulcerative Colitis Influence the Expression of MicroRNAs and Cytokines in the Sigmoid Mucosa in an Ex Vivo Model

Introduction UC is thought to be characterised by a TH-2 predominant immune response. MicroRNAs (miRNA) are short 19–23 nucleotide long strands of single-stranded RNA which modify post transcriptional gene expression by degrading or inhibiting translation of mRNA. miR31 and miR155 are miRNA that directly and indirectly target genes in the IL-13 dependant pathway. Confounding factors in current IBD miRNA studies include disease activity and medication. The specific function of miRNAs in UC, how they might be influenced by medications, and potential clinical utility is yet to be investigated. In this study we aim to investigate how the expression of a number of miRNA and mRNA is influenced by medications and then explore these findings further using a human ex-vivo culture system. Method Sigmoid biopsies from 40 patients with untreated active and inactive UC, normal controls, and patients treated with 5-ASA, Azathioprine, Infliximab and Adalimumab were frozen in liquid nitrogen. RT-qPCR was performed to analyse the relative expression of miRNA and mRNA. An ex vivo model was designed. 6 biopsies were taken from 8 patients with active untreated UC, with a Mayo score of 6 or greater. Biopsies were placed in tissue culture media in 6 separate wells with either no treatment, 5-ASA, 6-TG, Infliximab, or Adalimumab, were incubated for 24hrs at 37 o C. RT-qPCR was performed to assess expression of miR31 and miR155 and mRNA of CCL18 and SOCS1 that are important in the TH-2 pathway. Results miR31 and miR155 expression was increased in patients with untreated active and inactive UC compared to normal mucosa. CCL18 expression was also increased in untreated active disease compared to inactive and normal mucosa. Azathioprine reduced miR31, miR155 and CCL18 expression to levels seen in quiescent disease. Infliximab treatment reduced miR155, and CCL18 expression to that of inactive disease, which was not seen in Adalimumab. Anti-TNFs did not reduce miR31 expression to the level of untreated inactive disease. 5ASAs had no impact on expression of the miRNA nor mRNA studied. Ex vivo treated samples confirmed down regulation of miR31 was confined to 6-TG and not seen in anti-TNF treatment, and that CCL18 expression is also reduced by 6-TG and Infliximab, but not Adalimumab. Conclusion Our data confirmed that miR31 miR155 and CCL18 are increased in active UC compared to normal mucosa and inactive disease. We demonstrate that thiopurine therapy reduces expression of miR31 and CCl18 in contrast to anti-TNF agents. This model may have utility in increasing understanding of the mechanisms of action of IBD medications. It highlights the importance of controlling for medication when analysing miRNA expression in whole tissue biopsies. Disclosure of interest None Declared.

Efficacy and mode of action of mesalazine in the treatment of diarrhoea-predominant irritable bowel syndrome (IBS-D): a multicentre, parallel-group, randomised placebo-controlled trial

BackgroundDiarrhoea-predominant irritable bowel syndrome (IBS-D) is a common outcome after inflammation due to bacterial gastroenteritis. Several studies have shown ongoing immune activation in the mucosa of patients with IBS-D and a number of studies have suggested that mesalazine slow-release granule formulation (2 g; PENTASA®, Ferring Pharmaceuticals Ltd) may provide benefit including a reduction in stool frequency.ObjectivesOur primary aim was to compare the effect of mesalazine with placebo on stool frequency. Our secondary aims were to assess the effect of mesalazine on abdominal pain, stool consistency, urgency and satisfactory relief of irritable bowel syndrome (IBS) symptoms.Design/participants/interventionWe performed a double-blind, randomised placebo-controlled trial of 2 g mesalazine twice daily compared with placebo for 3 months in Rome III criteria patients with IBS-D.SettingsParticipants were recruited from the primary care research network and secondary care hospitals. Participants were randomised after a 2-week baseline stool diary. All participants completed a 12-week stool diary and at the end of each week recorded the presence of ‘satisfactory relief of IBS symptoms’. Those recruited in Nottingham had sigmoid biopsies and/or magnetic resonance imaging of the abdomen at the start and end of the trial.ResultsA total of 136 patients with IBS-D (82 female, 54 male) were randomised; 10 patients withdrew from each group. Analysis by intention to treat showed that the mean daily average stool frequency during weeks 11 and 12 was 2.8 [standard deviation (SD) 1.2] in the mesalazine group and 2.7 (SD 1.9) in the placebo group, with a group difference of 0.1 (95% confidence interval –0.33 to 0.53);p = 0.66.ConclusionsMesalazine did not improve abdominal pain, stool consistency or percentage with satisfactory relief compared with placebo during the last 2 weeks’ follow-up. A post hoc analysis in 13 postinfectious patients with IBS appeared to show benefit but this needs confirmation in a larger group. More precise subtyping based on underlying disease mechanisms may allow more effective targeting of treatment in IBS.Trial registrationCurrent Controlled Trials ISRCTN76612274.FundingThis project was funded by the Efficacy and Mechanism Evaluation (EME) programme, a MRC and NIHR partnership.

PTU-105 Expression Of Micrornas Mir-31, Mir-146a And Mir-155 Is Significantly Elevated In Anti-tnf-alpha Treatment Failure In Colonic Cd

IntroductionCrohn’s disease (CD) is a Th1/Th17 driven disease in which TNF-α and INF-γ play important roles. Anti-TNF-α drugs are used in moderate-severe CD to induce and maintain remission. Mucosal healing...

Large intestine permeability is increased in patients with compensated liver cirrhosis

Intestinal barrier dysfunction, facilitating translocation of bacteria and bacterial products, plays an important role in the pathophysiology of liver cirrhosis and its complications. Increased intestinal permeability has been found in patients with liver cirrhosis, but data on small and large intestine permeability and tight junctions (TJs) in patients with compensated cirrhosis are scarce. We aimed to investigate both small and large intestine permeability in patients with stable compensated cirrhosis compared with healthy controls and evaluated the expression of TJ proteins in mucosal biopsies at duodenal and sigmoid level. Intestinal permeability was assessed in 26 patients with compensated cirrhosis and 27 matched controls using a multisugar test. Duodenal and sigmoid biopsies were available from a subgroup for analyses of gene transcription and expression of key TJ proteins by qRT-PCR and ELISA, respectively. Median 0-5-h urinary sucrose excretion and lactulose/rhamnose ratio were comparable between patients with compensated cirrhosis and controls, whereas 5-24-h urinary sucralose/erythritol ratio was increased in these patients. Downregulation of gene transcription was found for claudin-3 in duodenal biopsies and claudin-4 in sigmoid biopsies, and at the protein level occludin expression was significantly increased in both duodenal and sigmoid biopsies. This study shows that gastroduodenal and small intestine permeability are not altered, whereas large intestine permeability is increased in patients with stable compensated cirrhosis. Only limited alterations were found regarding the expression of TJ proteins in both the small and large intestine.

The Relation and Value Of Endoscopy Biopsy In Different Sites For The Diagnosis Of Lower and Upper intestinal Graft-Versus-Host Disease

IntroductionGraft-versus-host disease (GvHD) causes morbidity and mortality in recipients of allogeneic hematopoietic stem cell transplantation (ASCT). This study assessed the distribution of GvHD in gastrointestinal (GI) biopsies from the upper and lower GI tract in all patients who had undergone ASCT in our institution between 2005 to 2013 and evaluated the correlation between biopsy of upper and lower GI, possible relation with CMV Infection in GI biopsy and Blood sample, GvHD GI grade and extra-intestinal manifestations of GvHD MethodsWe performed a retrospective pathology records review for all patients diagnosed with positive GI GvHD biopsy, who underwent both upper and lower endoscopy. We also reviewed pathology and clinical reports to determine which biopsy sites were diagnostic of GvHD and to evaluate for the possible presence of extra-intestinal manifestations GvHD at the time of biopsy, CMV Status on the biopsy findings and blood sample. ResultsOne hundred eighty nine patients (78 children and 111 adults) received ASCT transplant between 2005 to 2013. Twenty eight patients ( 14,8%) had undergone both upper and lower positive biopsy for acute GvHD diagnosis. Seventeen ( 60,7%) were male. The median age was 28 (1.50- 63.6) years old. Eleven patients had AML (39%), 6 had benign diseases (21.4%); five had ALL (17.9%); 2 lymphomas; 02 (7.1%) CML and 01 (3.1%) MDS. Main stem cell source was bone marrow 14 (50%), followed by PSCB in 7 (25%) and SCUP in 7 (25%). ATG was used in 16 (57, 1%) patients. Extra- intestinal manifestation of GVHD was: skin in 19 (67, 9%); liver in 6 (21,4%) patients. Five (17,9%) had the 3 organ involvement. The GI GvHD grade was: grade I in 7 ( 25%) , grade II in 4 ( 14,3%), grade III in 9 ( 32.1% ) and grade IV in 8 ( 28,6%). Regarding the concordance between the biopsy findings, there is agreement only between Ileum Biopsy Negative plus ileum and Rectum, because both have a higher percentage of positive GvHD. The stomach has a higher percentage of negative GvHD, and therefore there is no agreement with Colon plus ileum and Rectum. The frequency and correlation between involvement of different parts of GI-GVHD are presented in Tables 1,2 and 3. Just 2 ( 11.1%) patients had negative rectal biopsy and positive colon + ileum. Nine (32, 1%) had blood CMV detected. Five ( 17.9%) had positive Biopsy for CMV ( one in stomach, 3 in Colum and on in rectum), and just one patients had both positive.There is no association between clinical grade of GI-GVHD and the presence of CMV in biopsy and blood (CMV positive X GvHD grade, p=0.885; and biopsy CMV positive X GvHD grade, p= 0.859).It has no association between clinical grade of GI- GVHD and conditioning (p= 0.070) and use of ATG (p=0.867). HLA disparity was related with higher grades of GI-GVHD (p=0.029). All patients with Grade I are Fullmatch, whereas patients with Grade III and IV had highest percentage of mismatch [grade III= 5 (55.6%); and grade IV= 4 (57.15%) patients].The median follow up was 7.2 (1.8-90.6) month. Overall survival (OS) was 40% in 60 month and patients with grade IV GVHD had worst OS ( P= 0.004). ConclusionUse of sigmoid biopsy for GvHD diagnosis is effective, safe, and less expensive compared to other endoscopic interventions, because it was most frequent site of lower GI-GVHD and only 11% of biopsies were discordant. CMV infection may be underdiagnosted with this approach, where colonocospy study should be considered as most of CMV positivity in biopsy was in Colum. Disclosures:No relevant conflicts of interest to declare.

Colonic Involvement in Celiac Disease and Possible Implications of the Sigmoid Mucosa Organ Culture in its Diagnosis

Celiac disease (CD), a systemic autoimmune disorder that typically involves duodenal mucosa, can also affect other intestinal areas. Duodenal and oral mucosa organ culture has already been demonstrated as a reliable procedure to identify CD. The present study investigated gluten-dependent immunological activation of colonic mucosa in CD patients. We took advantage of the numerous colonoscopies performed for various clinical conditions or only for defensive medicine. Forty-four patients with gastrointestinal symptoms or in need of colorectal cancer screening were divided into patients with serum anti-endomysium (EMA) and anti-tissue transglutaminase (anti-tTG) antibody positive results (Group A), patients with serum antibody negative results (Group B), and patients with inflammatory bowel disease (IBD) (Group C). The autoantibodies EMA and anti-tTG were evaluated in supernatants of cultured sigmoid and duodenal biopsies from patients on a gluten-containing diet. In Group A, EMA and anti-tTG resulted positive in all duodenal culture supernatants. In sigmoid culture supernatants, EMA and anti-tTG were detected in 12/16 (75%) and 13/16 (81.3%) patients, respectively. In Group B, none of the 17 patients showed EMA and anti-tTG positive results in both duodenal and sigmoid cultures. In Group C, all 11 patients presented EMA negative results in sigmoid cultures. Only in one patient, anti-tTG were detectable in the sigmoid culture supernatant, as expected in cases of IBD. Data confirm that the gluten-dependent immunological activation affects more intestinal tracts with different degrees of involvement, suggesting that the organ culture of colonic biopsies could represent a new tool to opportunistically detect CD.

Endoscopy in the diagnosis of intestinal graft-versus-host disease: Is lower endoscopy with biopsy as effective in diagnosis as upper endoscopy combined with lower endoscopy?

Graft-versus-host disease (GvHD) causes morbidity and mortality in recipients of hematopoietic stem cell transplantation (SCT). This study assessed the distribution of GvHD in gastrointestinal (GI) biopsies from the upper and lower GI tract in pediatric patients who had undergone SCT and evaluated if there was correlation between biopsy findings and possible extra-intestinal manifestations of GvHD. We performed a retrospective chart review for all patients diagnosed with GvHD, who underwent both upper and lower endoscopy. We also reviewed pathology and clinical reports to determine which biopsy sites were diagnostic of GvHD and to evaluate for the possible presence of extra-intestinal manifestations GvHD at the time of biopsy. Twenty patients were identified who had undergone both upper and lower endoscopy for evaluation of GvHD. Patients with GvHD diagnosed on upper endoscopy also had GvHD identified in the sigmoid colon region 100% of the time (positive predictive value [PPV] = 1). In patients that were found to have underlying liver disease, GvHD was diagnosed in the sigmoid colon region 90% of the time (PPV = 0.9). Use of sigmoid biopsy for GvHD diagnosis is effective, safe, and less expensive compared to other endoscopic interventions.

Colonic Perforation After Rituximab Treatment for Posttransplant Lymphoproliferative Disorder

A 3-year-old girl presented with hematochezia. Her medical history included heart transplantation for hypoplastic left heart syndrome. Investigations demonstrated an Epstein-Barr virus polymerase chain reaction of 2307 genomes. Magnetic resonance enterography of the abdomen showed changes consistent with posttransplant lymphoproliferative disorder (PTLD) (Fig. 1). Her tacrolimus target trough was decreased to 4 to 7 ng/mL. Her initial colonoscopy showed ulcerations in the sigmoid colon and biopsies confirmed polymorphic PTLD (Fig. 2). She was treated with 4 weekly doses of rituximab and she remained clinically stable. Repeat colonoscopy to assess resolution of PTLD revealed a large perforation of the sigmoid colon; the patient subsequently underwent immediate bowel resection (Fig. 3). The gross specimen (Fig. 4) revealed granulation tissue, suggesting the perforation occurred before the colonoscopy. The pathology demonstrated persistent PTLD.FIGURE 1: Magnetic resonance enterography of the abdomen showing retroperitoneal lymphadenopathy, evidence of mesenteric infiltration, focal dilatation, and bowel wall thickening in the sigmoid colon (yellow arrow) suggestive of posttransplant lymphoproliferative disorder.FIGURE 2: Histology of colonic biopsy shows nuclear positivity for Epstein-Barr virus–encoded RNA (EBER) by in situ hybridization (black arrows) (EBER in situ hybridization; original magnification × 200).FIGURE 3: Colonoscopy performed postrituximab therapy. Large perforation noted in the sigmoid colon.FIGURE 4: Gross pathology specimen showing a 1.5-cm defect in the sigmoid colonic wall.PTLD is a rare but potentially fatal complication of solid organ transplantation. Extranodal involvement is highest within the gastrointestinal (GI) tract (1). In our case, rituximab, an anti-CD20 monoclonal antibody, was used to treat PTLD; however, its use has been associated with spontaneous GI perforation from rapid chemotherapeutic lysis of the tumor (2). Rituximab should be used cautiously in GI presentations of PTLD, especially in advanced disease and patients with multiple sites of involvement (3).

Metformin and biomarkers relevant to neoplasia in nondiabetic patients.

e14615 Background: Use of the anti-diabetic drug Metformin has been associated with reduced risk or improved prognosis of several cancers in both lab models and retrospective population studies of diabetics. Plausible mechanisms of action include (1) reduction in serum levels of insulin or inflammatory cytokines and (2) direct effects on target cells due to action of the drug as an inhibitor of mitochondrial respiration, including activation of AMPK. Methods: Non-diabetic subjects (n = 47) consented to bloodwork and sigmoid biopsy at screening colonoscopy, metformin administration (500 mg TID) for 10 weeks, and end-of-study sigmoid biopsy and bloodwork. Serum assays were performed on both fasting and post standard oral glucose load specimens. Metformin levels were measured by mass spectroscopy. Anti-phospho-histone-3 immunostaining was used to quantify proliferation. Results: Metformin reduced fasting levels of c-peptide, insulin, and IL-6 levels by < 10%, a magnitude of change that laboratory studies suggest is unlikely to be biologically significant. However, postprandial insulin levels following metformin were reduced by 18 % relative to baseline postprandial levels, a finding of potential physiologic relevance. Serum metformin level showed considerable variation between subjects (1005 ± 769 ng/ml) and this variation was not correlated with effects of metformin on epithelial proliferation. Proliferation index fell from 5.9 to 3.3, (p<0.03), a change greater than predicted by in vitro studies of direct action of metformin at the concentrations measured in serum. Conclusions: Metformin lowers insulin levels even in non-diabetic subjects, and post prandial insulin levels are more sensitive indicators of metformin action than fasting biomarkers. As high insulin level has been linked to increased cancer risk and/or worse prognosis (eg J Natl Cancer Inst. 2004;96:546), this systemic action suggests clinical applications. However, direct exposure of colonic epithelial cells to high luminal concentrations of metformin may also be relevant and is one of several factors that may explain the greater inhibitory effect of the drug on colonic epithelium proliferation than that previously reported for breast or prostate.

S100A Expression and Interleukin-10 Polymorphisms Are Associated with Ulcerative Colitis and Diarrhea Predominant Irritable Bowel Syndrome

Both ulcerative colitis (UC) and diarrhea-predominant irritable bowel syndrome (IBS-D) are associated with alterations in enteric serotonin (5-HT) signaling. The purpose of this study was to compare the rectal and sigmoid colonic mucosal expression of S100A proteins and functional polymorphisms of the 5-HT transporter (5HTT) and interleukin-10 genes in patients with IBS-D or UC with healthy controls. mRNA expression of S100 proteins was measured in sigmoid and rectal biopsies and in rectal epithelium isolated by laser-captured microdissection. Leucocyte DNA was analyzed by PCR-based reaction fragment length polymorphisms and direct sequencing. Clinical symptoms were assessed by the self-rating depression scale and by the gastrointestinal symptom rating scale. Fifty patients with IBS-D, 56 with UC and 50 healthy controls were studied. Colonic mucosal expression of S100A8 and S100A9 in UC was significantly higher than in IBS or controls and correlated with the UC disease activity index (r = 0.65, p < 0.001). S100A10 expression in the rectal epithelium of the IBS patients was significantly higher (0.643 vs. 0.402, p = 0.01) than in controls and correlated with the SDS scores (r = 0.41, p = 0.002). The frequency of IL10-819 CC genotype was significantly higher in IBS-D (10.7 vs. 0 %, p = 0.047) and UC (16 vs. 0 %, p = 0.007) than that in controls. Overexpression of S100A10 in the rectum may play a role in IBS as it is involved in modulating 5-HT1B receptors. The IL10-819 CC is a candidate genotype for both IBS and UC in Japanese.

Colonic mucosal microbiome differs from stool microbiome in cirrhosis and hepatic encephalopathy and is linked to cognition and inflammation

Although hepatic encephalopathy (HE) is linked to the gut microbiota, stool microbiome analysis has not found differences between HE and no-HE patients. This study aimed to compare sigmoid mucosal microbiome of cirrhotic patients to controls, between HE vs. no-HE patients, and to study their linkage with cognition and inflammation. Sixty cirrhotic patients (36 HE and 24 no-HE) underwent cognitive testing, stool collection, cytokine (Th1, Th2, Th17, and innate immunity), and endotoxin analysis. Thirty-six patients (19 HE and 17 no-HE) and 17 age-matched controls underwent sigmoid biopsies. Multitag pyrosequencing (including autochthonous genera, i.e., Blautia, Roseburia, Fecalibacterium, Dorea) was performed on stool and mucosa. Stool and mucosal microbiome differences within/between groups and correlation network analyses were performed. Controls had significantly higher autochthonous and lower pathogenic genera compared with cirrhotic patients, especially HE patients. HE patients had worse MELD (model for end-stage liver disease) score and cognition and higher IL-6 and endotoxin than no-HE. Mucosal microbiota was different from stool within both HE/no-HE groups. Between HE/no-HE patients, there was no difference in stool microbiota but mucosal microbiome was different with lower Roseburia and higher Enterococcus, Veillonella, Megasphaera, and Burkholderia abundance in HE. On network analysis, autochthonous genera (Blautia, Fecalibacterium, Roseburia, and Dorea) were associated with good cognition and decreased inflammation in both HE/no-HE, whereas genera overrepresented in HE (Enterococcus, Megasphaera, and Burkholderia) were linked to poor cognition and inflammation. Sigmoid mucosal microbiome differs significantly from stool microbiome in cirrhosis. Cirrhotic, especially HE, patients' mucosal microbiota is significantly different from controls with a lack of potentially beneficial autochthonous and overgrowth of potentially pathogenic genera, which are associated with poor cognition and inflammation.

A clinicopathological study of serotonin of sigmoid colon mucosa in association with chronic symptoms in uncomplicated diverticulosis

Neurotransmitter imbalance is hypothesised as a pathogenetic mechanism in several bowel conditions. We previously reported increased 5-HT in the sigmoid mucosa of colon resected for complicated diverticular disease (DD). We aimed to identify if abnormal 5-HT expression is associated with symptoms of uncomplicated DD. This was a prospective, comparative study and follow-up survey of symptoms. We examined the differences in 5-HT between DD patients and controls, as well as the presence of bowel symptoms at time of endoscopy and also 2years later. Sigmoid biopsies were collected at colonoscopy. Immunohistochemical staining for 5-HT cells was performed. Eighty-seven patients were recruited, 37 (42.5%) DD and 50 (57.5%) controls. No patients underwent surgery. There was no significant difference in total mean number of 5-HT-positive cells in DD compared to controls or between patients and controls with abdominal symptoms. Forty-one patients (47.1%) responded to questionnaires at median 57.8months from biopsy. Eighteen (43.9%) were DD and 23(56.1%) controls. 5-HT counts showed no significant association to symptom persistence. Although 5-HT expression has previously been found to be increased in complicated DD in whole bowel-resected specimens, the same is not confirmed on colonic mucosal biopsies. This raises the suggestion that 5-HT may be involved in the development of acute complications but may not be involved in the pathogenesis of chronic symptoms.

OC-119 Mechanistic randomised control trial of mesalazine in symptomatic diverticular disease

IntroductionPainful symptomatic diverticular disease (SDD) is a common but poorly understood condition. Approximately 20% of patients with diverticulosis complain of pain, but there are currently no effective treatments. We have...

Impact of multi-targeted antiretroviral treatment on gut T cell depletion and HIV reservoir seeding during acute HIV infection.

BackgroundLimited knowledge exists on early HIV events that may inform preventive and therapeutic strategies. This study aims to characterize the earliest immunologic and virologic HIV events following infection and investigates the usage of a novel therapeutic strategy.Methods and FindingsWe prospectively screened 24,430 subjects in Bangkok and identified 40 AHI individuals. Thirty Thais were enrolled (8 Fiebig I, 5 Fiebig II, 15 Fiebig III, 2 Fiebig IV) of whom 15 completed 24 weeks of megaHAART (tenofovir/emtricitabine/efavirenz/raltegravir/maraviroc). Sigmoid biopsies were completed in 24/30 at baseline and 13/15 at week 24.At baseline, the median age was 29 years and 83% were MSM. Most were symptomatic (87%), and were infected with R5-tropic (77%) CRF01_AE (70%). Median CD4 was 406 cells/mm3. HIV RNA was 5.5 log10 copies/ml. Median total blood HIV DNA was higher in Fiebig III (550 copy/106 PBMC) vs. Fiebig I (8 copy/106 PBMC) (p = 0.01) while the median %CD4+CCR5+ gut T cells was lower in Fiebig III (19%) vs. Fiebig I (59%) (p = 0.0008).After 24 weeks of megaHAART, HIV RNA levels of <50 copies were achieved in 14/15 in blood and 13/13 in gut. Total blood HIV DNA at week 0 predicted reservoir size at week 24 (p<0.001). Total HIV DNA declined significantly and was undetectable in 3 of 15 in blood and 3 of 7 in gut. Frequency of CD4+CCR5+ gut T cells increased from 41% at baseline to 64% at week 24 (p>0.050); subjects with less than 40% at baseline had a significant increase in CD4+CCR5+ T cells from baseline to week 24 (14% vs. 71%, p = 0.02).ConclusionsGut T cell depletion and HIV reservoir seeding increases with progression of AHI. MegaHAART was associated with immune restoration and reduced reservoir size. Our findings could inform research on strategies to achieve HIV drug-free remission.

Effect of raltegravir intensification on HIV proviral DNA in the blood and gut mucosa of men on long-term therapy

Highly active antiretroviral therapy (HAART) dramatically reduces plasma HIV-1 viremia. However, despite completely suppressive HAART, it has been suggested that low-levels of viral replication may persist in the gut mucosa and elsewhere in individuals on long-term HAART. We conducted a double-blind randomized, placebo-controlled trial evaluating whether intensification of HAART in long-term virologically suppressed individuals with raltegravir is associated with a reduction in the level of proviral HIV-1 DNA in CD4(+) T cells in blood and the sigmoid colon (gut). Long-term (>4 years) virologically suppressed HIV-infected individuals on standard HAART were randomized 1 : 1 in a double-blind fashion to receive raltegravir (400 mg twice/day) or placebo for 48 weeks. After week 48, all participants were treated with raltegravir to week 96. Blood and sigmoid biopsies were sampled and the frequency of CD4(+) T cells carrying HIV-1 proviral DNA was determined. Twenty-four study patients were recruited. At 48 weeks, no difference was apparent between participants receiving raltegravir or placebo in blood HIV-1 proviral levels (P = 0.62), CD4(+) T-cell counts (P = 0.25) and gut proviral loads (P = 0.74). Similarly, prolonged raltegravir intensification up to week 96 had no further effect on both blood and gut HIV-1 proviral loads and blood CD4(+) T-cell counts. In long-term virologically suppressed patients on standard HAART, intensification with raltegravir did not result in further decay of CD4(+) T cells carrying HIV-1 proviral DNA in either the blood or gut after 48 or 96 weeks of therapy, or in any increase in CD4(+) T-cell counts.

Prospective Evaluation of Acute Graft-Versus-Host Disease

Graft-versus-host disease (GVHD) is a common complication of allogeneic bone marrow transplantation. Severe GVHD carries significant morbidity and mortality and remains one of the leading causes of treatment failure. Unfortunately, intestinal GVHD may present with a variety of non-specific symptoms and diagnosis based on clinical presentation is often inaccurate; biopsy is therefore needed for definitive diagnosis. At present, the optimal endoscopic approach to the diagnosis of gastrointestinal GVHD remains uncertain. The primary aims of our study were: (1) to evaluate the yield of upper versus lower endoscopy, and (2) to determine which anatomic regions were most likely to provide a histologic diagnosis. We conducted a prospective study of 27 consecutive patients who had undergone stem cell transplantation within the past 100 days and were referred to the Yale Gastrointestinal Procedure center between August 2002 and February 2006 for the evaluation of suspected acute GVHD. All patients underwent standardized endoscopic evaluation of the upper and lower gastrointestinal tract with biopsies. The diagnostic yield of upper versus lower endoscopy was compared in all patients. GVHD was identified in 18 of the 27 patients (67%). Of those with GVHD, 15 patients (83%) had diffuse intestinal involvement. Six of 10 patients (60%) with an endoscopically normal EGD had GVHD on biopsies of the upper gastrointestinal tract. Six of 13 (46%) patients with an endoscopically normal appearing colonoscopy had GVHD on colonic biopsies. Two of 18 (11%) patients had isolated GVHD of the upper intestinal tract and 1 (6%) had isolated colonic GVHD. Rectal biopsy alone identified 89% (16 of 18) of GVHD cases and all 16 cases of GVHD with colonic involvement. A diagnosis of GVHD was not altered by the additional performance of biopsy of the proximal colon or terminal ileum. In the present study, the majority of cases of acute GVHD demonstrate diffuse upper and lower gastrointestinal involvement with rectal, sigmoid, gastric and duodenal biopsies having similarly diagnostic yield. Based on our findings, we recommend starting with flexible sigmoidoscopy with rectal biopsy alone in patients who are poor candidates to undergo full colonoscopy with sedation or in those in whom GVHD is strongly suspected based on clinical findings. However, more extensive evaluations may be necessary to rule out infection and should be considered in those with no contraindications to sedation and in whom other differential diagnoses are also being considered.

Symptoms in patients with ulcerative colitis in remission are associated with visceral hypersensitivity and mast cell activity

Objective. Patients with ulcerative colitis in remission (UCR) frequently report irritable bowel syndrome (IBS)-like symptoms. Recent studies have pointed to the role of mast cells in mediating visceral hypersensitivity in IBS. We hypothesized that visceral hypersensitivity is frequently present in patients with UCR and is related to the quantity and activity of mast cells in the sigmoid mucosa. Material and methods. A group of 17 controls and 19 patients with UCR were studied. Rectal compliance and perception were measured by electronic barostat. Sigmoid biopsies were taken to quantify the amount of mast cells, degranulating mast cells and mast cells in close proximity to mucosal nerve endings. Results. Visceroperception significantly increased in UCR (p < 0.05) versus controls. Rectal perception correlated positively with IBS-like symptoms in UCR (r = 0.969; p < 0.05). The amount of mucosal mast cells (per 100 crypts) was significantly increased in UCR versus controls: 228 ± 20 versus 163 ± 18 (p < 0.05). In the UCR patients a higher percentage of mucosal mast cells was in close proximity to nerve endings (58 ± 4 vs. 38 ± 3% in controls; p < 0.05) or was degranulating (40 ± 7 vs. 16 ± 4% in controls; p < 0.05). There was a significant but weak correlation between quantity of mucosal mast cells and pain perception (r = 0.32; p < 0.05). Conclusion. Rectal hypersensitivity is associated with mucosal presence and activation of mast cells and with IBS-like symptoms in patients with UCR.

Sigmoid Th17 populations, the HIV latent reservoir, and microbial translocation in men on long-term antiretroviral therapy

Th17 cells play an important role in mucosal defence and repair and are highly susceptible to infection by HIV. Antiretroviral therapy (ART) suppresses HIV viremia and can restore CD4(+) numbers in the blood and gastrointestinal mucosa, but the resolution of systemic inflammation and gut microbial translocation is often incomplete. We hypothesized that this might relate to persistent dysregulation of gut CD4(+) Th17 subsets. Blood and sigmoid biopsies were collected from HIV-uninfected men, chronically HIV-infected, ART-naive men, and men on effective ART for more than 4 years. Sigmoid provirus levels were assayed blind to participant status, as were CD4(+) Th17 subsets, systemic markers of microbial translocation, and cellular immune activation. There was minimal CD4(+) Th17 dysregulation in the blood until later stage HIV infection, but gastrointestinal Th17 depletion was apparent much earlier, along with increased plasma markers of microbial translocation. Plasma lipopolysaccharide (LPS) remained elevated despite overall normalization of sigmoid Th17 populations on long-term ART, although there was considerable interindividual variability in Th17 reconstitution. An inverse correlation was observed between plasma LPS levels and gut Th17 frequencies, and higher plasma LPS levels correlated with an increased gut HIV proviral reservoir. Sigmoid Th17 populations were preferentially depleted during HIV infection. Despite overall CD4(+) T-cell reconstitution, sigmoid Th17 frequencies after long-term ART were heterogeneous and higher frequencies were correlated with reduced microbial translocation.

Crohnʼs Colitis Complicated by “Secondary” Entamoeba Histolytica Infection

Purpose: Amebiasis, caused by Entamoeba histolytica, is a disease of worldwide importance and is estimated to result in 40,000 to 100,000 deaths annually. The clinical characteristics and colonoscopic findings of amebic colitis can resemble Inflammatory Bowel Disease. A 46 year old veteran with a past medical history of Crohn's disease diagnosed in 1993 presented to the outpatient clinic complaining of abdominal pain, intermittent bright red blood per rectum and chronic diarrhea. Previous evaluation of his chronic diarrhea included sigmoidoscopies in 2000, 2004, and 2008, all of which had biopsy proven Crohn's disease. The patient was started on Asacol 800 mg TID and Imuran 50 mg daily in 2000. Due to an inadequate clinical response, he was transitioned to Remicade in 2006. Despite symptom improvement, he stopped taking Remicade in 2009 because of insurance issues. The patient had no other past medical history and took no other medications. He also denied any recent antibiotic use, hospitalizations, or sick contacts. His travel included the East Coast of the U.S., Texas, and Southern California. While in the army, he spent significant time in Germany, France, Italy, and Austria. Stool studies were negative for ova/parasites, C. difficile toxin, Cryptosporidium and Giardia. A colonoscopy revealed flask shaped ulcers within the sigmoid colon and cecum. Sigmoid biopsies revealed trophozoites, consistent with E. histolytica; none of the biopsies were consistent with Crohn's disease. The patient's immune hemagglutination assay for E. histolytica and amebiasis were positive. The patient was started on metronidazole 500 mg 3 times daily for 10 days, followed by paromomycin 30 mg/kg PO daily for 7 days. After completion of metronidazole and paromomycin, the patient had complete resolution of his abdominal pain, bright red blood per rectum, and diarrhea. Patients with IBD have a greater prevalence of amebiasis as compared to the normal population. Diagnosis can be challenging as patients with E. histolytica often present with non specific symptoms such as diarrhea and abdominal pain. Examination of stool may reveal trophozoites of E. histolytica. Diagnosis can also be made using both the serum and indirect hemagglutination antibody and the enzyme linked immunosorbent assay, which are highly sensitive. Colonoscopic findings of amebic colitis can mimic IBD, and the presence of discrete ulcers with normal intervening mucosa is more likely to be mistaken for Crohn's disease. Metronidazole, 500 to 750 mg PO TID for 7 to 10 days, is the treatment of choice for invasive colitis. Because E. histolytica can persist in the intestine, it is recommended that treatment be followed with paromomycin.