Probe-based Confocal Laser Endomicroscopy for In Vivo Assessment of Histological Healing in Ulcerative Colitis: Development and Validation of the ENHANCE Index.

BACKGROUND AND AIMS: Histological healing may represent the ultimate therapeutic goal in ulcerative colitis [UC], but it requires biopsies. Our aim was to develop a non-invasive index able to assess histological disease activity in ulcerative colitis, using probe-based confocal laser endomicroscopy [pCLE]. METHODS: One hundred patients with quiescent UC were prospectively included in five French centres. After fluorescein intravenous injection, during colonoscopy, the colorectal mucosa was analysed by white light imaging and pCLE, and then biopsied in different locations. Five endoscopists performed central reading of pCLE images blinded to clinical, endoscopic, and histological data. One expert pathologist performed a central histological reading [Nancy index: gold standard]. Univariate and multivariate analyses were performed to identify the endomicroscopic items associated with the presence of histologically active disease. RESULTS: Over 1000 pCLE videos sequences performed in 100 UC patients in endoscopic remission [Mayo 0 and 1] were evaluated. We observed that vessel diameter >20 µm, dilated crypt lumen, fluorescein leakage, and irregular crypt architecture were statistically associated with histologically proven inflammation according to the Nancy index. Hence, we built a pCLE index of mucosal inflammation with overall accuracy of 79.6% and overall sensitivity and specificity of, respectively, 57.8% and 82.8%. Negative predictive value, especially when a pCLE index ≤1 was observed, was high [93.1%]. CONCLUSIONS: Using a robust methodology, large vessel diameter, dilated crypt lumen, fluorescein leakage,and irregular crypt architecture are reliable endomicroscopic items defining the ENHANCE index for real-time assessment of histological disease activity in UC.

Three-year effectiveness and safety of vedolizumab therapy for inflammatory bowel disease: a prospective multi-centre cohort study.

BACKGROUND: Cohort studies have described the short-term effectiveness and safety of vedolizumab in treating patients with Crohn's disease (CD) and ulcerative colitis (UC), but data beyond 1 year are lacking. AIM: To assess the effectiveness and safety of vedolizumab after 162 weeks in patients with UC and CD. METHODS: Between June and December 2014, 294 patients including 173 patients with CD and 121 with UC were treated with vedolizumab induction therapy. Among them, 149 continued to be treated with vedolizumab beyond week 54 (78 patients with CD and 71 with UC). Disease activity was assessed using the Harvey-Bradshaw Index for CD and the partial Mayo Clinic score for UC. The primary outcome was steroid-free clinical remission at week 162, computed for the whole population included at week 0. RESULTS: Steroid-free clinical remission rates at week 162 were 19.9% and 36.1% in patients with CD and UC respectively. Vedolizumab dose optimisation to 300 mg every 4 weeks instead of 300 mg every 8 weeks was at investigator's discretion and occurred in 58.7% and 52.1% of patients with CD and UC respectively. The 1-, 2- and 3-year persistence rates of vedolizumab were 48.5%, 31.4% and 26.3% respectively, in patients with CD and 61.0%, 49.9% and 42.9% respectively, in patients with UC. No new safety signal was identified. CONCLUSION: Vedolizumab is able to maintain steroid-free clinical remission in patients with UC and CD up to week 162. Loss of response resulting in discontinuation of vedolizumab occurred in 10% of patients per year.

Increasing Infliximab Dose Based on Symptoms, Biomarkers, and Serum Drug Concentrations Does Not Increase Clinical, Endoscopic, and Corticosteroid-Free Remission in Patients With Active Luminal Crohn's Disease.

BACKGROUND & AIMS: A combination of infliximab and immunomodulators is the most efficacious treatment for Crohn's disease (CD). Patients have the best outcomes when their serum concentrations of these drugs are above a determined therapeutic threshold. We performed a prospective, randomized trial to determine whether therapeutic drug monitoring (TDM) to maintain serum levels of infliximab above 3 µg/mL produced higher rates of clinical and endoscopic remission than adapting dose based only on symptoms. METHODS: We performed a double-blind trial in which 122 biologic-naïve adult patients with active CD (71 female, median age 29.8 years) received induction treatment with infliximab in combination with an immunosuppressant, from July 2012 through September 2015 at 27 centers in Europe. At week 14 of treatment, patients were randomly assigned (1:1:1) to 3 infliximab maintenance groups: dose increases (2 maximum) in steps of 2.5 mg/kg based on clinical symptoms and biomarker analysis and/or serum infliximab concentrations (dose intensification strategy [DIS]1 group); dose increase from 5 to 10 mg/kg based on the same criteria (DIS2 group); dose increase to 10 mg/kg based on clinical symptoms alone (controls). Patients' CD activity index scores, levels of C-reactive protein, fecal levels of calprotectin, and serum concentrations of infliximab were determined at baseline and at weeks 2, 4, 6, 12, and 14 of treatment, and then every 4 weeks thereafter until week 54. The primary endpoint was sustained corticosteroid-free clinical remission (CD activity index <150) from weeks 22 through 54 with no ulcers at week 54. RESULTS: The primary endpoint was reached by 15 (33%) of 45 patients in the DIS1 group, 10 (27%) of 37 patients in the DIS2 group, and 16 (40%) of 40 patients in the control group (P = .50). CONCLUSIONS: In a prospective randomized exploratory trial of patients with active CD, we found increasing dose of infliximab based on a combination of symptoms, biomarkers, and serum drug concentrations does not lead to corticosteroid-free clinical remission in a larger proportion of patients than increasing dose based on symptoms alone. EUDRACT NUMBER: 2011-003038-14.

Are random biopsies still useful for the detection of neoplasia in patients with IBD undergoing surveillance colonoscopy with chromoendoscopy?

BACKGROUND: Colonoscopy with pan-chromoendoscopy (CE) is superior to standard colonoscopy in detecting neoplasia in patients with IBD. Performing random biopsies in unsuspicious mucosa after CE remains controversial. METHODS: Consecutive patients with IBD who underwent surveillance colonoscopy using CE were prospectively included. The standardised procedure used CE, performed targeted biopsies or endoscopic resection on suspicious lesions and then quadrant random biopsies every 10 cm. A panel of five expert pathologists reviewed histological slides with dysplasia. Logistic regression model was used to evidence the factors associated with neoplasia in any or in random biopsies. RESULTS: 1000 colonoscopes were performed in 1000 patients (495 UC, 505 Crohn's colitis). In 82 patients, neoplasia was detected from targeted biopsies or removed lesions, and among them dysplasia was detected also by random biopsies in 7 patients. Importantly, in 12 additional patients dysplasia was only detected by random biopsies. Overall, 140 neoplastic sites were found in 94 patients, 112 (80%) from targeted biopsies or removed lesions and 28 (20%) by random biopsies. The yield of neoplasia by random biopsies only was 0.2% per-biopsy (68/31 865), 1.2% per-colonoscopy (12/1000) but 12.8% per-patient with neoplasia (12/94). Dysplasia detected by random biopsies was associated with a personal history of neoplasia, a tubular appearing colon and the presence of primary sclerosing cholangitis (PSC). CONCLUSIONS: Despite their low yield, random biopsies should be performed in association with CE in patients with IBD with a personal history of neoplasia, concomitant PSC or a tubular colon during colonoscopy. TRIAL REGISTRATION NUMBER: IRB 001508, Paris 7 University.

Efficacy of adalimumab in patients with Crohn's disease and symptomatic small bowel stricture: a multicentre, prospective, observational cohort (CREOLE) study.

OBJECTIVE: The efficacy of anti-tumour necrosis factors (anti-TNFs) in patients with Crohn's disease (CD) and symptomatic small bowel stricture (SSBS) is controversial. The aim of this study was to estimate the efficacy of adalimumab in these patients and to identify the factors predicting success. DESIGN: We performed a multicentre, prospective, observational cohort study in patients with CD and SSBS. The included patients underwent magnetic resonance enterography at baseline and subsequently received adalimumab. The primary endpoint was success at week 24, defined as adalimumab continuation without prohibited treatment (corticosteroids after the eight week following inclusion, other anti-TNFs), endoscopic dilation or bowel resection. The baseline factors independently associated with success were identified using a logistic regression model, leading to a simple prognostic score. Secondary endpoints were prolonged success after week 24 (still on adalimumab, without dilation nor surgery) and time to bowel resection in the whole cohort. RESULTS: From January 2010 to December 2011, 105 patients were screened and 97 were included. At week 24, 62/97 (64%) patients had achieved success. The prognostic score defined a good prognosis group with 43/49 successes, an intermediate prognosis group with 17/28 successes and a poor prognosis group with 1/16 successes. After a median follow-up time of 3.8 years, 45.7%±6.6% (proportion±SE) of patients who were in success at week 24 (ie, 29% of the whole cohort) were still in prolonged success at 4 years. Among the whole cohort, 50.7%±5.3% of patients did not undergo bowel resection 4 years after inclusion. CONCLUSIONS: A successful response to adalimumab was observed in about two-thirds of CD patients with SSBS and was prolonged in nearly half of them till the end of follow-up. More than half of the patients were free of surgery 4 years after treatment initiation. CLINICAL TRIAL REGISTRATION NUMBER: NCT01183403; Results.

Costs of Crohn's Disease According to Severity States in France: A Prospective Observational Study and Statistical Modeling over 10 Years.

BACKGROUND: To describe the medico-economic characteristics of Crohn's disease (CD), we implemented a multicenter study in France. METHODS: From 2004 to 2006, disease severity states, direct (hospital and extra hospital) and indirect costs were prospectively collected over 1 year in patients with CD naive from anti-tumor necrosis factor alpha (infliximab) at inclusion. Economic valorization was performed from the French Social Insurance perspective, and a statistical modeling over 10 years was performed. RESULTS: In 341 patients, the mean total costs of management were &OV0556;6024 per year (&OV0556;4675 for direct costs). As compared to patients in remission, costs were 4 to 6 times higher in patients in an active period and 19 times higher for patients requiring surgery (SURG). The most important expense items were medical and surgical hospitalizations (56% of total costs), including cost of infliximab (36% of hospitalization costs, i.e., 20% of total costs), indirect costs (22%), and drugs (11%). The statistical modeling over 10 years showed that most of the clinical course was spent in drug-responsive state (54%) with 26% of costs or in remission (32%) with 11% of costs; time spent in a SURG state was small (3.2%) but generated 48% of total costs. CONCLUSIONS: Before the introduction of self-injectable anti-tumor necrosis factor alpha, the most important expenses were supported by hospitalizations, explaining why the most costly states were for patients requiring SURG or dependent on inhospital administrated drugs. Projected data show that most time is spent in a stabilized state with appropriate treatments or in remission, and that costs associated with SURG are high.

Interobserver Variation Study of the Rutgeerts Score to Assess Endoscopic Recurrence after Surgery for Crohn's Disease.

BACKGROUND: After resection surgery for Crohn's disease, recurrence of endoscopic lesions at the site of the anastomosis or in the neoterminal ileum is graded according to the Rutgeerts score (RS). The goal of this study was to test the interobserver variability for RS. METHODS: Thirteen trained endoscopists evaluated the RS on 39 videotapes of patients who had undergone resection for Crohn's disease with an ileocolonic anastomosis 6 months earlier. Videotapes were randomly assigned to endoscopists through a balanced incomplete block design. Each videotape was scored independently by four endoscopists, and each endoscopist evaluated 12 videotapes, making a total of 156 videotape assessments. Reproducibility levels of the RS were assessed through unweighted kappa estimates among multiple raters. The proportion of inappropriate therapeutic initiation was estimated by randomly selecting one endoscopist for each videorecording, assuming that the majority of endoscopists correctly classified endoscopic recurrence. RESULTS: The kappa estimates were 0.43 (95% confidence interval: 0.33-0.52) for the RS on a 5-grade scale, 0.47 (0.28-0.66) for RS < i2 vs. ≥ i2, and 0.64 (0.42-0.85) for RS ≤ i2 vs. > i2. The percentages of inappropriate therapeutic initiation were 12.8% (3.8-21.9) when initiation was triggered by a RS ≥ i2 and 8.3% (1.1-15.6) when initiation was triggered by a RS > i2 (p = 0.41). CONCLUSION: The reproducibility of the RS was moderate, especially when differentiating 10% of patients.

Effectiveness and Safety of Vedolizumab Induction Therapy for Patients With Inflammatory Bowel Disease.

BACKGROUND & AIMS: Phase 3 trials have shown the efficacy of vedolizumab, which binds to integrin α4ß7, in patients with Crohn's disease (CD) or ulcerative colitis (UC). We investigated the effectiveness and safety of vedolizumab in patients who failed anti-tumor necrosis factor therapy. METHODS: From June through December 2014, there were 173 patients with CD and 121 patients with UC who were included in a multicenter nominative compassionate early access program granted by French regulatory agencies. This program provided patients with access to vedolizumab before it was authorized for marketing. Vedolizumab (300 mg) was administered intravenously at weeks 0, 2, and 6, and then every 8 weeks. Disease activity was assessed using the Harvey-Bradshaw Index for CD and the partial Mayo Clinic score for UC. We report results obtained after the 14-week induction phase. RESULTS: Among the 294 patients treated with vedolizumab (mean age, 39.5 ± 14.0 y; mean disease duration, 10.8 ± 7.6 y; concomitant steroids, 44% of cases), 276 completed the induction period, however, 18 discontinued vedolizumab because of a lack of response (n = 14), infusion-related reaction (n = 2), or infections (n = 2). At week 14, 31% of patients with CD were in steroid-free clinical remission and 51% had a response; among patients with UC, 36% were in steroid-free clinical remission and 50% had a response. No deaths were reported. Severe adverse events occurred in 24 patients (8.2%), including 15 (5.1%) that led to vedolizumab discontinuation (1 case of pulmonary tuberculosis and 1 rectal adenocarcinoma). CONCLUSIONS: In a cohort of patients with CD or UC who failed previous anti-tumor necrosis factor therapy, approximately one third of patients achieved steroid-free clinical remission after 14 weeks of induction therapy with vedolizumab. This agent had an acceptable safety profile in these patients.

Drug resistance in inflammatory bowel diseases.

The management of patients with moderate to severe inflammatory bowel diseases, that is, Crohn's disease and ulcerative colitis, remains challenging. In recent years, therapeutic goal evolved from clinical remission to mucosal healing and deep remission. In order to achieve remission, it is important to appropriately choose and use available drugs. Therefore, anti-TNFα treatment should be rapidly used for severe and at-risk patients, sometimes in association with thiopurines or methotrexate. The monitoring of through levels and antibodies to anti-TNFα is relevant to optimize the treatment and to reduce drug inefficacy. However, the development of new drugs is required to offer alternative tools to severe and refractory patients.

Long-term outcome of enterocutaneous fistula in patients with Crohn's disease treated with anti-TNF therapy: a cohort study from the GETAID.

OBJECTIVES: Although anti-tumor necrosis factor (TNF) therapy is the treatment of choice for perianal fistulizing Crohn's disease (CD), the efficacy and safety of anti-TNF therapy in enterocutaneous fistula (ECF) remains unclear. METHODS: Between January 2008 and December 2009, we retrospectively reviewed the outcomes of all CD patients with ECF (excluding perianal fistula) treated with anti-TNF therapy followed up in Groupe d'Etude Thérapeutique des Affections Inflammatoires du tube Digestif (GETAID) centers. ECF closure and tolerance of anti-TNF therapy were studied using univariate and multivariate analyses. RESULTS: Forty-eight patients (twenty-six women; median age 34.6 (interquartile range=25.0-45.5) years) were included in this study. The median follow-up period was 3.0 (2.0-6.6) years. The fistula was located in the small bowel (n=38), duodenum (n=1), and colon (n=9). The fistula has been developed in ileocolonic anastomosis in 17 (35%) cases. Sixteen patients (33%) had complex fistulas with multiple tracts and eleven patients (23%) had a high ECF output (if wearing an ostomy bag). Complete ECF closure was achieved in 16 (33%) patients, of whom eight relapsed during the follow-up period. In multivariate analysis, complete ECF closure was associated with the absence of multiple ECF tracts and associated stenosis. An abdominal abscess developed in 15 (31%) patients. ECF resection was needed in 26 (54%) patients. One patient died after surgery owing to abdominal sepsis. CONCLUSIONS: In CD patients with ECF, anti-TNF therapy may be effective in up to one-third of patients, especially in the absence of stenosis and complex fistula. A careful selection of patients is mandatory to prevent treatment failure and improves the safety.

[Crohn's disease and ulcerative colitis]. / La maladie de Crohn et la rectocolite hémorragique.

Extremely variable in their clinical expression, inflammatory bowl diseases evolve by flare-ups interspersed with phases of remission. Complications can be severe, sometimes requiring surgery. While treatments have evolved considerably, therapeutic patient education plays an important role in the therapeutic approach.

Adaptor proteins intersectin 1 and 2 bind similar proline-rich ligands but are differentially recognized by SH2 domain-containing proteins.

BACKGROUND: Scaffolding proteins of the intersectin (ITSN) family, ITSN1 and ITSN2, are crucial for the initiation stage of clathrin-mediated endocytosis. These proteins are closely related but have implications in distinct pathologies. To determine how these proteins could be separated in certain cell pathways we performed a comparative study of ITSNs. METHODOLOGY/PRINCIPAL FINDINGS: We have shown that endogenous ITSN1 and ITSN2 colocalize and form a complex in cells. A structural comparison of five SH3 domains, which mediated most ITSNs protein-protein interactions, demonstrated a similarity of their ligand-binding sites. We showed that the SH3 domains of ITSN2 bound well-established interactors of ITSN1 as well as newly identified ITSNs protein partners. A search for a novel interacting interface revealed multiple tyrosines that could be phosphorylated in ITSN2. Phosphorylation of ITSN2 isoforms but not ITSN1 short isoform was observed in various cell lines. EGF stimulation of HeLa cells enhanced tyrosine phosphorylation of ITSN2 isoforms and enabled their recognition by the SH2 domains of the Fyn, Fgr and Abl1 kinases, the regulatory subunit of PI3K, the adaptor proteins Grb2 and Crk, and phospholipase C gamma. The SH2 domains mentioned were unable to bind ITSN1 short isoform. CONCLUSIONS/SIGNIFICANCE: Our results indicate that during evolution of vertebrates ITSN2 acquired a novel protein-interaction interface that allows its specific recognition by the SH2 domains of signaling proteins. We propose that these data could be important to understand the functional diversity of paralogous ITSN proteins.

Early administration of azathioprine vs conventional management of Crohn's Disease: a randomized controlled trial.

BACKGROUND & AIMS: Immunomodulator therapy is effective for patients with Crohn's disease (CD) but has not been shown to affect disease progression, presumably because it is given too late after diagnosis. We compared the efficacy of early treatment (within 6 months after diagnosis) with azathioprine versus conventional management of patients at high risk for disabling disease. METHODS: We performed an open-label trial of adults with a diagnosis of CD for less than 6 months who were at risk for disabling disease. From July 2005 to November 2010, patients at 24 French centers were randomly assigned to treatment with azathioprine (2.5 mg ∙ kg(-1) ∙ day(-1), n = 65) or conventional management (azathioprine only in cases of corticosteroid dependency, chronic active disease with frequent flares, poor response to corticosteroids, or development of severe perianal disease) (n = 67). The primary end point was the proportion of trimesters spent in corticosteroid-free and anti-tumor necrosis factor (TNF)-free remission during the first 3 years after inclusion. RESULTS: During the 3-year follow-up period, 16 patients in the azathioprine group were switched to mercaptopurine or methotrexate therapy because of intolerance or poor efficacy. Forty-one patients in the conventional management group required immunosuppressant therapy (61%; median time to first prescription, 11 months). In the azathioprine group, a median 67% of trimesters were spent in remission (interquartile range, 11%-85%) compared with 56% in the conventional management group (interquartile range, 29%-73%) (P = .69). Among secondary outcomes, a higher cumulative proportion of patients in the azathioprine group were free of perianal surgery than in the conventional management group (96% ± 3% and 82% ± 6% at month 36, respectively; P = .036). The cumulative proportion of patients free of intestinal surgery and anti-TNF therapy did not differ between groups. CONCLUSIONS: Based on results from a clinical trial, administration of azathioprine within 6 months of diagnosis of CD was no more effective than conventional management in increasing time of clinical remission. Clinicaltrials.gov, Number NCT00546546.

Endoscopic ultrasound and magnetic resonance cholangiopancreatography in patients with idiopathic acute pancreatitis.

BACKGROUND: The efficacy of endoscopic ultrasonography (EUS) to diagnose idiopathic acute pancreatitis has been demonstrated but that of magnetic-resonance cholangiopancreatography (MRCP) remains unclear. AIMS: The aim of our study was to prospectively compare the results of EUS and MRCP to diagnose idiopathic acute pancreatitis when performed later after an acute attack. METHODS: All patients admitted to our center for acute pancreatitis over a 2-year period received first-line investigations that included medical history, standard biological measurements, abdominal ultrasound, and computerized tomography. If no etiology was found, second-line investigations were scheduled at 2 months (or more if there was severe pancreatitis), which included clinical examinations, biological parameters, EUS, and MRCP. RESULTS: A total of 128 consecutive patients were included (male: 80, mean age: 55.3 years). After first-line investigations, 41 patients with idiopathic acute pancreatitis underwent second-line investigations and were followed-up (38 patients had both EUS and MRCP). EUS and/or MRCP led to recognize a possible etiology of pancreatitis in 19 patients (50 %). The diagnostic yield for EUS was higher than for MRCP (29 vs. 10.5 %). EUS more accurately detected biliary stones whereas MRCP identified pancreatic duct abnormalities, such as intraductal papillary mucinous neoplasm of the pancreas or chronic pancreatitis. CONCLUSIONS: The combination of EUS and MRCP, when performed later after idiopathic acute pancreatitis, revealed 50 % of etiologies. The association of these two procedures and the subsequent follow-up reduced the rate of idiopathic pancreatitis by ~66 %.

Portomesenteric vein thrombosis in patients with inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease (IBD) is associated with a high risk of deep venous thromboembolism. However, few data are available so far on portomesenteric vein thrombosis (PMVT). The aim of this study was to describe the characteristics of PMVT in patients with IBD. METHODS: A retrospective study was conducted at 13 GETAID (Groupe d'Etude Thérapeutique des Affections Inflammatoires du Tube Digestif) centers from January 1995 to June 2010. The following data were collected, using a standardized questionnaire: characteristics of IBD, disease status at the time of PMVT, PMVT characteristics and mode of discovery, concomitant prothrombotic disorders, anticoagulant therapy, and evolution of PMVT. RESULTS: Fifty cases (29 men and 21 women; median age, 41 years) were identified, including 14 patients with ulcerative colitis and 36 with Crohn's disease. Thirty-one patients (62%) presented with acute PMVT. Twenty-four patients had previously undergone surgical treatment, and IBD was active in 23 cases (77%) of acute thrombosis. The discovery of PMVT was fortuitous in 40% of our cases. Among the 43 patients screened for a prothrombotic disorder, abnormalities were observed in 17 patients (40%) (mainly hyperhomocysteinemia, n = 12). Forty-four patients (88%) were treated with anticoagulants. Recanalization of the vein was significantly more successful in patients with acute thrombosis (65% versus 37%, P = 0.05). CONCLUSIONS: PMVT can occur when IBD is inactive, and its diagnosis was fortuitous in 40% of our cases. Screening for prothrombotic disorders is essential because it is positive in more than one third of cases.

Dynamics of the subcellular localization of RalBP1/RLIP through the cell cycle: the role of targeting signals and of protein-protein interactions.

The small G protein Ras regulates many cell processes, such as gene expression, proliferation, apoptosis, and cell differentiation. Its mutations are associated with one-third of all cancers. Ras functions are mediated, at least in part, by Ral proteins and their downstream effector the Ral-binding protein 1 (RalBP1). RalBP1 is involved in endocytosis and in regulating the dynamics of the actin cytoskeleton. It also regulates early development since it is required for the completion of gastrulation in Xenopus laevis. RalBP1 has also been reported to be the main transporter of glutathione electrophiles, and it is involved in multidrug resistance. Such a variety of functions could be explained by a differential regulation of RalBP1 localization. In this study, we have detected endogenous RalBP1 in the nucleus of interphasic cells. This nuclear targeting is mediated by nuclear localization sequences that map to the N-terminal third of the protein. Moreover, in X. laevis embryos, a C-terminal coiled-coil sequence mediates RalBP1 retention in the nucleus. We have also observed RalBP1 at the level of the actin cytoskeleton, a localization that depends on interaction of the protein with active Ral. During mitosis RalBP1 also associates with the mitotic spindle and the centrosome, a localization that could be negatively regulated by active Ral. Finally, we demonstrate the presence of post-transcriptional and post-translational isoforms of RalBP1 lacking the Ral-binding domain, which opens new possibilities for the existence of Ral-independent functions.

Long-term clinical and imaging follow-up of nonoperated branch duct form of intraductal papillary mucinous neoplasms of the pancreas.

OBJECTIVES: The aim of our study was to perform a 10-year imaging and clinical prospective follow-up of patients with nonoperated branch duct (BD) intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. METHODS: Forty-nine patients with BD-IPMN who displayed a low probability for malignancy were followed up including a clinical component and a series of imaging techniques such as computed tomography, magnetic resonance cholangiopancreatography, and endoscopic ultrasonography. RESULTS: After a mean follow-up period of 77 months, 77.5% of patients remained free of symptoms. An increase in the size and number of BD cysts without mural nodules and with no significant increase of main duct size occurred in 18 patients at an average interval of 47 months. Five patients were operated on owing to recurrent pancreatitis and/or an increase in the size of either cysts or the main duct (mean time delay after diagnosis: 20 months). Pathologically, they were diagnosed as benign adenoma (n = 1) or borderline (n = 4). CONCLUSIONS: Our long-term clinical and imaging follow-up indicated that none of the patients with BD-IPMNs developed malignancy. Therefore, BD-IPMNs with no signs of malignancy should be managed conservatively. We propose that following a 2-year patient follow-up, biannual imaging follow-ups could be sufficient.

Is Crohn's creeping fat an adipose tissue?

BACKGROUND: In human pathology, the "creeping fat" (CF) of the mesentery is unique to Crohn's disease (CD). CF is usually referred to as an ectopic extension of mesenteric adipose tissue (MAT). However, since no animal model developing CF has ever been established, very little is known about this type of fat-depot expansion and its role in the development of the disease. METHODS: We developed and standardized an experimental protocol in mice that reproducibly induces CF development when a severe colonic inflammation is obtained by intracolonic instillation of DNBS. RESULTS: Macro-microscopic observations revealed a fatty appearance of CF. Yet when compared to MAT from the same animals, CF contains very little triglycerides, few adipocytes, and we observed a very low expression and protein levels of both adipose markers (hormone-sensitive lipase, perilipin) and adipocytokines (leptin, adiponectin). The decreased expression of perilipin in CF was also observed by immunohistochemistry. Conversely, the expression of proinflammatory and fibrous markers (Pref-1) was much higher in CF than in MAT. These observations were fully consistent with those made on CF recovered from five CD patients and compared with subcutaneous and mesenteric fat from the same patients. CONCLUSIONS: Altogether, this work reports an original experimental mice model of CF. In this model we establish for the first time that CF only occurs in severe colonic inflammation and shows an inflammatory, fibrous but not an adipose pattern.