Fucosyltransferase 2 Mutations Are Associated With a Favorable Clinical Course in Crohn's Disease.

BACKGROUND: Fucosyltransferase 2 (FUT2) participates in intestinal antigen secretion and bacterial adherence. FUT2 homozygous nonsense mutations (FUT2M) and subsequent nonsecretor status is associated with Crohn's disease (CD). The common null allele is rs601338. We assessed the relationship between FUT2M and disease course. METHODS: In consecutive adult CD outpatients, clinical, biochemical, and genetic data were collected at baseline visits. Patients were longitudinally followed over 5 years. The primary outcome analyzed the relationship between FUT2M and rates of CD patients in persistent steroid-free clinical remission requiring neither surgery, biologics, nor immunomodulators. RESULTS: Sixty-two CD patients were recruited. FUT2M homozygotes (rs601338 or any mutation in linkage disequilibrium) were detected in 27% of CD (17/62). Patients with rs601338 mutations had higher rates of the primary outcome (homozygous: 46.6%, heterozygous: 28.0%, wild-type: 5.3%, P=0.02). Similar findings existed for CD patients with homozygous mutations in any single-nucleotide polymorphism for FUT2 (homozygous: 41.2%, heterozygous: 25.9%, wild-type: 5.6%, P=0.04). On multivariable analysis, rs601338 mutation was associated with the primary outcome (odds ratio=3.4, 95% confidence interval: 1.3-8.7, P=0.01), while other parameters were not. Mutation of rs601338 was associated with lower rates of penetrating disease (homozygous: 13.3%, heterozygous: 28.0%, wild-type: 52.6%, P=0.05) and particularly in high-risk patients (homozygous: 0%, heterozygous: 37.5%, wild-type: 83.3%, P=0.01). CONCLUSIONS: FUT2 mutation status is associated with a favorable clinical course in CD. Further confirmatory studies are needed.

Increased Intestinal Permeability Is Associated With Later Development of Crohn's Disease.

BACKGROUND & AIMS: Increased intestinal permeability has been associated with Crohn's disease (CD), but it is not clear whether it is a cause or result of the disease. We performed a prospective study to determine whether increased intestinal permeability is associated with future development of CD. METHODS: We assessed the intestinal permeability, measured by the urinary fractional excretion of lactulose-to-mannitol ratio (LMR) at recruitment in 1420 asymptomatic first-degree relatives (6-35 years old) of patients with CD (collected from 2008 through 2015). Participants were then followed up for a diagnosis of CD from 2008 to 2017, with a median follow-up time of 7.8 years. We analyzed data from 50 participants who developed CD after a median of 2.7 years during the study period, along with 1370 individuals who remained asymptomatic until October 2017. We used the Cox proportional hazards model to evaluate time-related risk of CD based on the baseline LMR. RESULTS: An abnormal LMR (>0.03) was associated with a diagnosis of CD during the follow-up period (hazard ratio, 3.03; 95% CI, 1.64-5.63; P = 3.97 × 10-4). This association remained significant even when the test was performed more than 3 years before the diagnosis of CD (hazard ratio, 1.62; 95% CI, 1.051-2.50; P = .029). CONCLUSIONS: Increased intestinal permeability is associated with later development of CD; these findings support a model in which altered intestinal barrier function contributes to pathogenesis. Abnormal gut barrier function might serve as a biomarker for risk of CD onset.

Low Rate of Drug Discontinuation, Frequent Need for Dose Adjustment, and No Association with Development of New Arthralgia in Patients Treated with Vedolizumab: Results from a Tertiary Referral IBD Center.

BACKGROUND: Evaluating clinical data on the safety and efficacy of vedolizumab (VDZ) in 'real-world' setting is still desirable. Recent reports have raised concerns that arthralgia may be associated with VDZ. AIMS: The aim of this study is to present clinical experience with VDZ from a tertiary IBD center. METHODS: Retrospective chart reviews were performed of consecutive patients exposed to VDZ between 2015 and 2018. Clinical, biomarker, and endoscopic efficacy and safety data were evaluated. RESULTS: A total of 130 IBD (75CD, 55UC) patients were included. Median duration of VDZ therapy was 65 weeks. Probability of drug discontinuation was 4.9% and 9.4% at 1 and 2 years. Dose intensification was more frequent in CD compared to UC (at 1 and 2 years: 64.8/87.9% vs. 26.5/35.7%, p < 0.001). Clinical remission rates at 3-, 6- and 12 months were 44.4%, 71.4% and 77.1% in UC, and 9.1%, 26.7% and 29.2% in CD patients, respectively. Prior use of multiple biologic agents was associated with diminished efficacy of VDZ in CD. Three new cases of arthralgia were encountered during follow-up. CONCLUSION: Vedolizumab (VDZ) therapy displayed good drug sustainability and clinical efficacy in a population with severe disease phenotype and high rates of previous anti-TNF failure. Frequent dose intensification was required. The safety profile was good, and no association between newly onset arthralgia and VDZ therapy was observed.

Clinical Parameters Correlate With Endoscopic Activity of Ulcerative Colitis: A Systematic Review.

BACKGROUND & AIMS: Optimal management of patients with ulcerative colitis (UC) requires assessment of disease activity-usually by endoscopy, which is invasive, costly, and not risk free. We performed a systematic review to determine whether clinical symptoms correlate with findings from endoscopy assessments of patients with UC. METHODS: We performed a systematic review of publication databases from January 1980 through July 2018 to identify clinical trials and observational studies reporting correlations among symptoms, disease activity index scores and/or patient reported outcomes (rectal bleeding and/or stool frequency), and endoscopic disease activity. Correlations were ascertained in patients with active vs inactive disease and by disease extent and treatment type. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Because of significant heterogeneity, meta-analysis was not possible. Results were synthesized qualitatively and systematically. RESULTS: Our final analysis included 23 studies (1 randomized trial, 22 observational studies) comprising 3320 patients with UC. The studies used a variety of measures to assess clinical activity, endoscopic activity, and measures of correlation (sensitivity, specificity, correlation coefficients, area under the receiver operator curve). Overall, studies were at moderate-high risk of bias. Composite clinical measures, including rectal bleeding and stool frequency, had moderate to strong correlations with endoscopic disease activity; the absence of rectal bleeding identified patients with inactive disease with higher levels of sensitivity than normalization of stool frequency. In general, symptoms correlated more strongly with endoscopic activity in patients with left-sided colitis than extensive colitis. The effect of different medications on the correlation between clinical and endoscopic activity has not been well studied. CONCLUSIONS: In a systematic review, we found a moderate to strong correlation between clinical activity, particularly the combination of rectal bleeding and stool frequency, and endoscopic activity in patients with UC. Although these clinical assessments could help prioritize patients for endoscopic evaluation in resource-limited settings, challenges associated with treating patients based on symptoms alone preclude adaptation of current management algorithms.

Understanding Chylomicron Retention Disease Through Sar1b Gtpase Gene Disruption: Insight From Cell Culture.

BACKGROUND: Understanding the specific mechanisms of rare autosomal disorders has greatly expanded insights into the complex processes regulating intestinal fat transport. Sar1B GTPase is one of the critical proteins governing chylomicron secretion by the small intestine, and its mutations lead to chylomicron retention disease, despite the presence of Sar1A paralog. OBJECTIVE: The central aim of this work is to examine the cause-effect relationship between Sar1B expression and chylomicron output and to determine whether Sar1B is obligatory for normal high-density lipoprotein biogenesis. APPROACH AND RESULTS: The SAR1B gene was totally silenced in Caco-2/15 cells using the zinc finger nuclease technique. SAR1B deletion resulted in significantly decreased secretion of triglycerides (≈40%), apolipoprotein B-48 (≈57%), and chylomicron (≈34.5%). The absence of expected chylomicron production collapse may be because of the compensatory SAR1A elevation observed in our experiments. Therefore, a double knockout of SAR1A and SAR1B was engineered in Caco-2/15 cells, which led to almost complete inhibition of triglycerides, apolipoprotein B-48, and chylomicron output. Further experiments with labeled cholesterol revealed the downregulation of high-density lipoprotein biogenesis in cells deficient in SAR1B or with the double knockout of the 2 SAR1 paralogs. Similarly, there was a fall in the movement of labeled cholesterol from cells to basolateral medium containing apolipoprotein A-I, thereby limiting newly synthesized high-density lipoprotein in genetically modified cells. The decreased cholesterol efflux was associated with impaired expression of ABCA1 (ATP-binding cassette subfamily A member 1). CONCLUSIONS: These findings demonstrate that the deletion of the 2 SAR1 isoforms is required to fully eliminate the secretion of chylomicron in vitro. They also underscore the limited high-density lipoprotein production by the intestinal cells in response to SAR1 knockout.

A Study of Optimal Screening for Latent Tuberculosis in Patients with Inflammatory Bowel Disease.

BACKGROUND: Reactivation of LTBI in patients with IBD on anti-TNF-α agents can lead to serious life-threatening illness. No gold standard exists for the detection of LTBI. We examined whether a dual testing strategy with TST and IGRA would improve the detection of LTBI. METHODS: Consecutive IBD patients being considered for anti-TNF-α treatment underwent testing with a TST, IGRA and CXR. All patients completed a self-administered questionnaire. The association of both tests with demographic factors, LTBI risk factors, BCG vaccination, IS therapy and agreement between the TST and IGRA were evaluated. RESULTS: One-hundred and fifty-five IBD patients were included, 6% were TST positive and 5% were IGRA positive. Concordance between TST and IGRA was fair (κ = 0.21, 95% CI - 0.081-0.498). Neither test was affected by age, gender or BCG vaccination. The presence of risk factors for LTBI was found to be positively associated with TST (OR 19.8, 95% CI 3.9-102.1), but not IGRA. IGRA was negatively associated with IS therapy (OR 0.06, 95% CI 0.007-0.5), but not TST. Four patients who were IGRA positive but TST negative were treated for LTBI by a respirologist. CONCLUSION: An IGRA result was negatively associated with IS therapy, while the presence of risk factors for LTBI was found to be positively associated with TST results. There was fair agreement between positive TST and IGRA results. The addition of IGRA to the standard practice of TST and CXR increased the number of cases that were initiated on LTBI therapy.

Association Between Ustekinumab Trough Concentrations and Clinical, Biomarker, and Endoscopic Outcomes in Patients With Crohn's Disease.

BACKGROUND & AIMS: Ustekinumab, an inhibitor of the p40 subunit of interleukins 12 and 23, is an effective treatment for patients with Crohn's disease (CD). Trough concentrations of tumor necrosis factor (TNF) antagonists and presence of anti-drug antibodies are associated with important clinical and endoscopic outcomes. We investigated associations between trough concentrations of ustekinumab and clinical, biomarker, and endoscopic outcomes of real-world patients with CD. METHODS: We recruited 62 patients with CD who were either refractory or intolerant to TNF antagonists, treated with ustekinumab from April 2014 to September 2015. Patients received 90 mg of ustekinumab subcutaneously at weeks 0, 1, and 2 during induction and 90 mg every 4 or 8 weeks during maintenance. Clinical, biomarker, and endoscopic outcomes, trough concentrations of ustekinumab, and anti-drug antibodies were assessed at both week 10 postinduction therapy and at week 26 or later during maintenance therapy in a prospective longitudinal patient cohort or at week 26 or later during maintenance therapy in a cross-sectional patient cohort. Analysis was performed on data combined from both maintenance cohorts, which had similar outcomes at week 26 or later. A primary analysis determined if ustekinumab drug trough concentrations were associated with clinical response (reduction in Harvey Bradshaw Index score of 3 or greater), clinical remission (Harvey Bradshaw Index score <5), steroid-free clinical remission, biomarker (serum level of C-reactive protein [CRP] or level of fecal calprotectin) reduction, biomarker normalization (serum level of CRP below 5 mg/L or level of fecal calprotectin below 200 µg/g), endoscopic response (simple endoscopic score for CD reduced by 50% or more), or endoscopic remission (simple endoscopic score for CD of 2 or less). RESULTS: At week 26 or beyond, 80.7% of patients had a clinical response, 66.1% were in clinical remission, 50.0% were in steroid-free clinical remission, 58.9% had an endoscopic response, and 19.6% were in endoscopic remission. The mean trough concentration of ustekinumab at this time point was higher in patients with an endoscopic response (4.7 µg/mL) than without (3.8 ug/mL; P = .03). An optimal ustekinumab threshold trough concentration at week 26 or later was found to be 4.5 µg/mL (area under the curve, 0.67). A greater proportion of patients with trough concentrations of ustekinumab above 4.5 µg/mL at week 26 or later had an endoscopic response (75.9%) than did patients with trough concentrations below this level (40.7%; P = .008). Patients with trough concentrations of ustekinumab above 4.5 µg/mL at week 26 or later also had a lower mean level of CRP (12.6 mg/L) than did patients with trough concentrations below this level (mean level of CRP, 23.9 mg/L; P = .04). We did not detect antibodies against ustekinumab in any patient. CONCLUSIONS: Ustekinumab therapy was effective in patients with CD who had not responded to or were intolerant to treatment with a TNF antagonist. Maintenance trough concentrations of ustekinumab above 4.5 µg/mL at 26 weeks or later were associated with biomarker reduction and endoscopic response.

Vitamin D Reduces Colitis- and Inflammation-Associated Colorectal Cancer in Mice Independent of NOD2.

Inflammatory bowel disease (IBD) patients are at increased risk of developing colorectal cancer (CRC). Vitamin D (vD) induces NOD2 gene expression, enhancing immunity, while deficiency impairs intestinal epithelial integrity, increasing inflammation. This study investigated the effect of vD on CRC in colitis, and if preventive benefits are mediated via NOD2. Inflammation-associated CRC was induced by treating C57BL/6J and Nod2-/- mice with azoxymethane (AOM) and dextran sodium sulfate (DSS) cycles (×3). vD-deficient mice displayed more severe colitis compared to vD-supplemented mice, with greater weight loss, higher colitis activity index, increased colonic weight/length ratios, and lower survival rates. Increased histological inflammation score and increased IL-6 were observed in the mucosa of vD-deficient mice. Overall incidence of colonic tumors was not significantly different between vD-deficient and vD-supplemented mice. Higher tumor multiplicity was observed in vD-deficient vs vD-supplemented groups (both mouse strains). After AOM/DSS treatment, decreased plasma 25(OH)D3 levels and downregulation of vD target genes Cyp24 and Vdr were observed in both mice strains (vD-deficient or vD-supplemented diet), compared to saline-treated controls on the vD-deficient diet. In conclusion, vD supplementation reduced colitis severity and decreased the number of inflammation-associated colorectal tumors in both C57BL/6J and Nod2-/- mice, independent of NOD2.

A phenotype of IGFBP-3 knockout mice revealed by dextran sulfate-induced colitis.

BACKGROUND AND AIM: Insulin-like growth factor-1 (IGF-1) bioactivity has been shown to be attenuated by insulin-like growth factor binding protein-3 (IGFBP-3), one of six IGF-binding proteins. While prior work revealed no major phenotype associated with IGFBP-3 knockout mice, we explored the possibility that a phenotype could be revealed under specific conditions of gastrointestinal stress. METHODS: The dextran sodium sulfate (DSS) murine model of ulcerative colitis was used for this study. RESULTS: Insulin-like growth factor binding protein-3 knockout mice had significantly reduced colitis on exposure to DSS as measured by lower levels of pro-inflammatory cytokines IL-6 (P < 0.0001), TNF-α (P = 0.0035), and IL-1ß (P = 0.0112), reduced weight loss (P < 0.0001), reduced myeloperoxidase activity (P = 0.0025), and maintenance of colorectal length (P < 0.05), all relative to wild-type mice exposed to DSS. IGFBP-3 knockout mice also exhibited increased colon epithelial cell proliferation (P < 0.0001) following DSS exposure. Semi-quantitative immunohistochemistry showed greater IGF-1 receptor activation in colon epithelial cells of IGFBP-3 knockout mice compared with control mice following DSS exposure. CONCLUSION: Our data demonstrate that IGFBP-3 influences severity of DSS-induced colitis. The observations suggest that in the absence of IGFBP-3, enhanced IGF bioactivity leads to increased epithelial proliferation and mucosal barrier repair, thereby lessening inflammation.

Use of patency capsule in patients with established Crohn's disease.

BACKGROUND AND STUDY AIMS: Video capsule endoscopy (VCE) is invaluable in the diagnosis of small-bowel pathology. Capsule retention is a major concern in patients with Crohn's disease. The patency capsule was designed to evaluate small-bowel patency before VCE. However, the actual benefit of the patency capsule test in Crohn's disease remains unclear. The aim of this study was to evaluate the clinical impact of patency capsule use on the risk of video capsule retention in patients with established Crohn's disease. PATIENTS AND METHODS: This was a retrospective, multicenter study of patients with established Crohn's disease who underwent VCE for clinical need. The utilization strategy for the patency capsule was classified as selective (only in patients with obstructive symptoms, history of intestinal obstruction or surgery, or per treating physician's request) or nonselective (all patients with Crohn's disease). The main outcome was video capsule retention in the entire cohort and within each utilization strategy. RESULTS: A total of 406 patients who were referred for VCE were included in the study. VCE was performed in 132 /406 patients (32.5 %) without a prior patency capsule test. The patency capsule test was performed in 274 /406 patients (67.5 %) and was negative in 193 patients. Overall, VCE was performed in 343 patients and was retained in the small bowel in 8 (2.3 %). In this cohort, the risk of video capsule retention in the small bowel was 1.5 % without use of a prior patency capsule and 2.1 % after a negative patency test (P = 0.9). A total of 18 patients underwent VCE after a positive patency capsule test, with a retention rate of 11.1 % (P = 0.01). Patency capsule administration strategy (selective vs. nonselective) was not associated with the risk of video capsule retention. CONCLUSIONS: Capsule retention is a rare event in patients with established Crohn's disease undergoing VCE. The risk of video capsule retention was not reduced by the nonselective use of the patency capsule. Furthermore, VCE after a positive patency capsule test in patients with Crohn's disease was associated with a high risk of video capsule retention.

Association Between Fecal Calprotectin Levels and Small-bowel Inflammation Score in Capsule Endoscopy: A Multicenter Retrospective Study.

BACKGROUND: Accurate inflammation reporting in capsule endoscopy (CE) is important for diagnosis and monitoring of treatment of inflammatory bowel disease (IBD). Fecal calprotectin (FC) is a highly specific biomarker of gut inflammation. Lewis score (LS) was developed to standardize quantification of inflammation in small-bowel (SB) CE images. GOALS: Multicenter retrospective study aiming to investigate correlation between LS and FC in a large group of patients undergoing CE for suspected or known small-bowel IBD, and to develop a model for prediction of CE results (LS) based on FC levels. STUDY: Five academic centers and a district general hospital offering CE in UK, Finland, Sweden, Canada, and Israel. In total, 333 patients were recruited. They had small-bowel CE and FC done within 3 months. RESULTS: Overall, correlation between FC and LS was weak (r s: 0.232, P < 0.001). When two clinically significant FC thresholds (100 and 250 µg/g) were examined, the r s between FC and LS was 0.247 (weak) and 0.337 (moderate), respectively (P = 0.307). For clinically significant (LS ≥ 135) or negative (LS < 135) for SB inflammation, ROC curves gave an optimum cutoff point of FC 76 µg/g with sensitivity 0.59 and specificity 0.41. LIMITATIONS: Retrospective design. CONCLUSIONS: LS appears to show low correlation with FC as well as other serology markers of inflammation. FC does not appear to be a reliable biomarker for significant small-bowel inflammation. Nevertheless, FC level ≥ 76 µg/g may be associated with appreciable visual inflammation on small-bowel CE in patients with negative prior diagnostic workup.

New Insights In Intestinal Sar1B GTPase Regulation and Role in Cholesterol Homeostasis.

Sar1B GTPase is a key component of Coat protein complex II (COPII)-coated vesicles that bud from the endoplasmic reticulum to export newly synthesized proteins. The aims of this study were to determine whether Sar1B responds to lipid regulation and to evaluate its role in cholesterol (CHOL) homeostasis. The influence of lipids on Sar1B protein expression was analyzed in Caco-2/15 cells by Western blot. Our results showed that the presence of CHOL (200 µM) and oleic acid (0.5 mM), bound to albumin, increases Sar1B protein expression. Similarly, supplementation of the medium with micelles composed of taurocholate with monooleylglycerol or oleic acid also stimulated Sar1B expression, but the addition of CHOL (200 µM) to micelle content did not modify its regulation. On the other hand, overexpression of Sar1B impacted on CHOL transport and metabolism in view of the reduced cellular CHOL content along with elevated secretion when incubated with oleic acid-containing micelles for 24 h, thereby disclosing induced CHOL transport. This was accompanied with higher secretion of free- and esterified-CHOL within chylomicrons, which was not the case when oleic acid was replaced with monooleylglycerol or when albumin-bound CHOL was given alone. The aforementioned cellular CHOL depletion was accompanied with a low phosphorylated/non phosphorylated HMG-CoA reductase ratio, indicating elevated enzymatic activity. Combination of Sar1B overexpression with micelle incubation led to reduction in intestinal CHOL transporters (NPC1L1, SR-BI) and metabolic regulators (PCSK9 and LDLR). The present work showed that Sar1B is regulated in a time- and concentration-dependent manner by dietary lipids, suggesting an adaptation to alimentary lipid flux. Our data also suggest that Sar1B overexpression contributes to regulation of CHOL transport and metabolism by facilitating rapid uptake and transport of CHOL.

Diagnostic modalities for the evaluation of small bowel disorders.

PURPOSE OF REVIEW: This review summarizes the recent developments in the evaluation of small bowel disorders using videocapsule endoscopy (VCE) and serological and breath-test biomarkers. RECENT FINDINGS: The ability to visualize the small bowel was revolutionized with the introduction of VCE technology. VCE allows for accurate, noninvasive visualization of the small bowel mucosa. This device is invaluable in the investigation of obscure gastrointestinal bleeding (OGIB), occult bleeding with iron deficiency anaemia, small bowel Crohn's disease (CD), small bowel neoplasms and other mucosal disorders. Recent studies underscored the utility of VCE for documenting the extent and severity of small bowel CD as well as monitoring activity after therapy. The accuracy of the discrimination between small bowel tumours and benign bulges has been improved by a novel endoscopic algorithm. The accuracy of VCE was also evaluated as a potential noninvasive alternative to small bowel biopsies in suspected celiac disease. New findings have been made using breath tests and other biomarkers for the diagnosis of celiac disease, irritable bowel syndrome and bacterial overgrowth. SUMMARY: VCE as well as breath-test biomarkers play a major and expanding role in the diagnosis and monitoring of various small bowel disorders.

Hematologic indices as surrogate markers for monitoring thiopurine therapy in IBD.

BACKGROUND: Clinical efficacy and risk of complications are associated with intracellular levels of thiopurine metabolites 6-thioguanine nucleotides (6-TGN) and 6-methylmercaptopurines (6-MMP) in patients with Crohn's disease. Therapeutic monitoring of thiopurine metabolites is not widely available. Surrogate markers such as hematologic indices (MCV, leukopenia) have been proposed. AIMS: To evaluate accuracy of hematologic indices for prediction of therapeutic levels of thiopurine metabolites. METHODS: A retrospective cross-sectional study. We included patients treated with thiopurines for IBD between February 2008 and November 2013. Hematologic indices were correlated with thiopurine metabolites and compared to pre-treatment levels. RESULTS: A total of 168 patients with 608 measurements were included. Macrocytosis was observed in 4.5 % of the patients. On multivariate analysis, macrocytosis was associated with 6-TGN levels >235 pmol/8 × 10(8) erythrocytes and 6-mmp levels >5,700 pmol/8 × 10(8) erythrocytes. Therapeutic 6-TGN levels were associated with MCV, ΔMCV, macrocytosis and lymphocyte count. Sensitivity and Spearman's r correlation for prediction of therapeutic metabolite levels were poor for all hematologic indices. CONCLUSION: Although macrocytosis and an elevated MCV are associated with therapeutic 6-TGN levels, the correlation is weak. None of the evaluated hematologic indices is a reliable surrogate marker for thiopurine metabolite levels.

Capsule endoscopy is superior to small-bowel follow-through and equivalent to ileocolonoscopy in suspected Crohn's disease.

BACKGROUND & AIMS: Evaluation of the small intestine for inflammation has traditionally relied on small-bowel follow-through (SBFT), but multiple studies have demonstrated its low diagnostic accuracy. Capsule endoscopy (CE) transmits high-quality images of the small intestinal mucosa; it can be used to visualize the entire length of the small bowel and much of the mucosa. We compared the diagnostic yields of CE vs SBFT in a prospective study of patients with suspected small-bowel Crohn's disease. METHODS: Eighty patients with signs and/or symptoms of small-bowel Crohn's disease (age, 10-65 years) underwent CE, followed by SBFT and ileocolonoscopy. Readers were blinded to other test results. The primary outcome was the diagnostic yield for inflammatory lesions found with CE before ileocolonoscopy compared with SBFT and ileocolonoscopy. A secondary outcome was the incremental diagnostic yield of CE compared with ileocolonoscopy and CE compared with SBFT. RESULTS: The combination of CE and ileocolonoscopy detected 107 of 110 inflammatory lesions (97.3%), whereas the combination of SBFT and ileocolonoscopy detected only 63 lesions (57.3%) (P < .001). The diagnostic yield of CE compared with ileocolonoscopy was not different (P = .09). The diagnostic yield was higher for CE than for SBFT (P < .001). Of the 80 patients with suspected Crohn's disease, 25 (31.3%) had the diagnosis confirmed. Eleven were diagnosed by CE findings alone and 5 by ileocolonoscopy findings alone. In the remaining 9 patients, diagnostic findings were identified by at least 2 of the 3 modalities. No diagnoses were made on the basis of SBFT findings alone. CONCLUSIONS: CE was better than SBFT and equivalent to ileocolonoscopy in detecting small-bowel inflammation. Although ileocolonoscopy remains the initial diagnostic test of choice, CE is safe and can establish the diagnosis of Crohn's disease in patients when ileocolonoscopy results are negative or the terminal ileum cannot be evaluated. ClinicalTrials.gov Number: NCT00487396.

Tissue distribution and regulation of the small Sar1b GTPase in mice.

BACKGROUND/AIMS: Sar1b GTPase (Sar1b) represents an obligatory component of COPII vesicles that bud from the endoplasmic reticulum to transport proteins to the Golgi apparatus. Its genetic mutations lead to a severe disorder known as chylomicron retention disease. Despite growing knowledge on Sar1b, little is known about it tissue distribution and regulation, which constitute the aims of the present study. We aimed to determine the Sar1b tissue distribution and modulation by a high-fat diet and gene forcing using transgenic mice in comparison to wild-type mice. Methods : The expression pattern of Sar1b was studied in different organs of wild-type and Sar1b transgenic mice by qRT-PCR and Western blot. The effect of transgenesis and insulin resistance induced by a 12-week high-fat diet on Sar1b gene expression was also assessed by qRT-PCR. RESULTS: Evaluation of Sar1b mRNA revealed the skeletal muscle as the tissue with the highest Sar1b expression, followed by the heart and liver, the organs composing the digestive tract, the brain and finally the lung and the adipose tissue. Sar1b protein expression levels follow a similar pattern among the organs, except for its lower expression in the heart. While the high-fat diet did not exert any significant alterations, Sar1b transgenic mice displayed higher gene expression in the liver, ileum, jejunum, proximal and distal colon compared to wild-type mice. CONCLUSION: Our study supports the importance of Sar1b in organs involved in lipid transport and/or calcium trafficking such as the liver, intestine, skeletal muscle and heart.

Ulcerative jejunitis in a child with celiac disease.

BACKGROUND: Celiac disease can present in children and adults with a variety of manifestations including a rare complication known as ulcerative jejunitis. The latter has been associated with refractory celiac disease in adult onset patients. The objective of this case report is to describe the first pediatric case of ulcerative jejunitis in celiac disease, diagnosed by capsule endoscopy, which was not associated with refractory celiac disease. CASE PRESENTATION: The 9 year old girl presented with a history of abdominal pain and vomiting. Laboratory investigations revealed a slightly elevated IgA tissue transglutaminase antibody level in the setting of serum IgA deficiency. Initial upper endoscopy with biopsies was not conclusive for celiac disease. Further investigations included positive IgA anti-endomysium antibody, and positive HLA DQ2 typing. Video capsule endoscopy showed delayed appearance of villi until the proximal to mid jejunum and jejunal mucosal ulcerations. Push enteroscopy with biopsies subsequently confirmed the diagnosis of celiac disease and ulcerative jejunitis. Immunohistochemical studies of the intraepithelial lymphocytes and PCR amplification revealed surface expression of CD3 and CD8 and oligoclonal T cell populations. A repeat capsule study and upper endoscopy, 1 year and 4 years following a strict gluten free diet showed endoscopic and histological normalization of the small bowel. CONCLUSION: Ulcerative jejunitis in association with celiac disease has never previously been described in children. Capsule endoscopy was essential to both the diagnosis of celiac disease and its associated ulcerative jejunitis. The repeat capsule endoscopy findings, one year following institution of a gluten free diet, also suggest that ulcerative jejunitis is not always associated with refractory celiac disease and does not necessarily dictate a poor outcome.

Deleterious effects of indomethacin in the mid-gestation human intestine.

The use of the anti-inflammatory drug indomethacin (INDO) in preterm infants has been associated with an increased risk of developing enteropathies. In this study, we have investigated the direct impact of INDO on the human mid-gestation intestinal transcriptome using serum-free organ culture. After determining the optimal dose of 1 µM of INDO (90% inhibition of intestinal prostaglandin E2 production and range of circulating levels in treated preterm babies), global gene expression profiles were determined using Illumina bead chip microarrays in both small and large intestines after 48 h of INDO treatment. Using Ingenuity Pathway Analysis software, we identified critical metabolic pathways that were significantly altered by INDO in both intestinal segments including inflammation and also glycolysis, oxidative phosphorylation and free radical scavenging/oxidoreductase activity, which were confirmed by qPCR at the level of individual genes. Taken together, these data revealed that INDO directly exerts multiple detrimental effects on the immature human intestine.

Anti-inflammatory effects of epidermal growth factor on the immature human intestine.

The inflammatory response of the preterm infants' intestine underlines its inability to respond to hemodynamic stress, microbes, and nutrients. Recent evidence suggests that exogenous epidermal growth factor (EGF) exerts a therapeutic influence on neonatal enteropathies. However, the molecular mechanisms underlying the beneficial effects of EGF remain to be clarified. The purpose of this study was to evaluate the impact of EGF on the gene expression profiles of the developing human small and large intestine at midgestation in serum-free organ cultures using microarrays. The gene expression profiles of cultured human fetal ileal and colonic explants were investigated in the absence or presence of a physiological concentration of 50 ng/ml EGF for 48 h. Data were analyzed with the Ingenuity Pathway Analysis (IPA) software and confirmed by qPCR. We found a total of 6,474 differentially expressed genes in the two segments in response to EGF. IPA functional analysis revealed that in addition to differentially modulating distinct cellular, molecular, and physiological functions in the small and large intestine, EGF regulated the inflammatory response in both intestinal segments in a distinct manner. For instance, several intestinal-derived chemokines such as CCL2, CCL25, CXCL5, and CXCL10 were found to be differentially regulated by EGF in the immature ileum and colon. The findings showing the anti-inflammatory influence of exogenous EGF suggests a mechanistic basis for the beneficial effects of EGF on neonatal enteropathies. These results reinforce growing evidence that by midgestation, the human small intestine and colon rely on specific and distinct regulatory pathways.

Antioxidative properties of paraoxonase 2 in intestinal epithelial cells.

Paraoxonase (PON) family members seem central to a wide variety of human illnesses, but appreciation of their antioxidative function in the gastrointestinal tract is in its infancy. The major objective of the present work is to highlight the role of the ubiquitously expressed PON2 in the small intestine. With use of pLKO lentiviral vector containing short hairpin RNA (shRNA) lentivirus, PON2 expression was knocked down in intestinal Caco-2/15 cells, where antioxidative status, lipid peroxidation, and degree of inflammation were evaluated. As a consequence of PON2 inactivation in the epithelial cells, we observed 1) imbalanced primary and secondary antioxidative responses, characterized by increased superoxide dismutases and decreased catalase, 2) high concentrations of H(2)O(2) and malondialdehyde, along with low glutathione-to-glutathione disulfide ratio, 3) upregulation of TNF-α, IL-6, and monocyte chemoattractant protein-1 gene expression after induction of oxidative stress, and 4) raised level of the activation of transcription factor NF-κB, which was likely implicated in exacerbation of the inflammatory activation. These results suggest that PON2 is involved in the antioxidative and anti-inflammatory response in intestinal epithelial cells.