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Dive into the research topics where Marcel Groenen is active.

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Featured researches published by Marcel Groenen.


Canadian Journal of Gastroenterology & Hepatology | 2009

Incidence of duodenal ulcers and gastric ulcers in a Western population: back to where it started.

Marcel Groenen; Ernst J. Kuipers; Bettina E. Hansen; Rob J. Ouwendijk

BACKGROUND/OBJECTIVES As recently as 40 years ago, a decline in the incidence of peptic ulcers was observed. The discovery of Helicobacter pylori had a further major impact on the incidence of ulcer disease. Our aim was to evaluate the trends in the incidence and bleeding complications of ulcer disease in the Netherlands. METHODS From a computerized endoscopy database of a district hospital, the data of all patients who underwent upper gastrointestinal endoscopy from 1996 to 2005 were analyzed. The incidence of duodenal and gastric ulcers, with and without complications, were compared over time. RESULTS Overall, 20,006 upper gastrointestinal endoscopies were performed. Duodenal ulcers were diagnosed in 696 (3.5%) cases, with signs of bleeding in 158 (22.7%). Forty-five (6.5%) of these ulcers were classified as Forrest I and 113 (16.2%) as Forrest II. Gastric ulcers were diagnosed in 487 cases (2.4%), with signs of bleeding in 60 (12.3%). A Forrest 1 designation was diagnosed in 19 patients (3.9%) and Forrest 2 in 41 patients (8.4%). The incidence of gastric ulcers was stable over time, while the incidence of duodenal ulcers declined. CONCLUSIONS The incidence of duodenal ulcer disease in the Dutch population is steadily decreasing over time. Test and treatment regimens for H pylori have possibly contributed to this decline. With a further decline in the prevalence of H pylori, the incidence of gastric ulcers is likely to exceed the incidence of duodenal ulcers in the very near future, revisiting a similar situation that was present at the beginning of the previous century.


Gastrointestinal Endoscopy | 2015

Safety experience with the duodenal-jejunal bypass liner: an endoscopic treatment for diabetes and obesity

Bark Betzel; Parviez Koehestanie; Edo O. Aarts; Kemal Dogan; Jens Homan; Ignace Janssen; Peter J. Wahab; Marcel Groenen; Frits J. Berends

BACKGROUND The duodenal-jejunal bypass liner (DJBL) is a new, device-based endoscopic treatment for type 2 diabetes mellitus (T2DM) and obesity. OBJECTIVE To report serious safety events of subjects treated with the DJBL while offering a simple guideline to mitigate risk. DESIGN Single-center observational study. SETTING Tertiary referral center. PATIENTS For commercial use, patients were eligible for implantation of the DJBL when they met the following criteria: age 18 to 65 years, body mass index 28 to 45 kg/m(2), T2DM, and negative serum Helicobacter pylori test. INTERVENTIONS Endoscopic implantation of the DJBL. MAIN OUTCOME MEASUREMENTS Adverse events, serious adverse events, early explantation. RESULTS Between October 2007 and January 2014, 152 of 165 planned implantations (92%) and 94 explantations were performed in our center. Significant weight loss and improvement in T2DM and other cardiovascular parameters were achieved. Early removal of the device occurred because of persistent GI symptoms in 16 patients (11%). Serious adverse events were observed in a subset of patients: 7 GI bleeds, 5 of which required early removal; 2 cases of pancreatitis; 1 case of hepatic abscess; and 1 obstruction of the sleeve. Explantation resulted in an esophageal tear in 2 cases. LIMITATIONS Single-center study. CONCLUSION The DJBL improves glycemic control while causing weight loss. The safety profile of the DJBL demonstrates a reasonable tolerability profile. However, serious safety adverse events can occur. Patient selection, expert use of the device at placement and removal, and the supportive care of an experienced multidisciplinary team are key for safe and effective use of the DJBL.


Digestive Surgery | 2012

Routine screening for colon cancer after conservative treatment of diverticulitis.

Pim J.C. Schout; Ernst Jan Spillenaar Bilgen; Marcel Groenen

Background and Aims: It is generally advised to perform colonoscopy after conservatively treated diverticulitis because colon cancer may present itself with similar symptoms, laboratory and radiological results. With this study we investigated in what percentage of patients a malignancy was found by performing routine colonoscopy or radiologic imaging after a conservatively treated episode of diverticulitis, and whether this follow-up programme could be reserved for a selected group of patients. Methods: In our hospital, routine colonoscopy or, as a second choice, radiologic imaging has been standard practice over the last decade. We collected all colonoscopy and radiologic imaging results that were conducted of all 516 patients who were diagnosed with diverticulitis in this period. Results: Of those 516 patients, 378 had undergone colonoscopy, 45 radiologic imaging and 93 did not undergo any additional investigation. Eight cases of malignant neoplasia were found in those patients (2.1%), and an additional number of 40 adenomatous polyps (9.5%). Six out of 8 patients with colon cancer reported rectal blood loss, significant weight loss or persisting abdominal pain after being treated for diverticulitis. Conclusions: In patients who were conservatively treated with routine colonoscopy or radiologic imaging for apparent diverticulitis, a malignant tumour was found in the colon in 2.1% of them. If only performed in patients reporting alarm symptoms, a case of colon cancer would be missed in only 0.5% of patients conservatively treated for diverticulitis. Therefore, screening for colon cancer after conservative treatment of diverticulitis is only indicated in symptomatic patients.


Digestive Diseases and Sciences | 2007

Gastrointestinal Endoscopic Terminology Coding (GET-C): A WHO-Approved Extension of the ICD-10

Marcel Groenen; Willem Hirs; Henk Becker; Ernst J. Kuipers; Gerard P. van Berge Henegouwen; P. Fockens; Rob J. Ouwendijk

Technological developments have greatly promoted interest in the use of computer systems for recording findings and images at endoscopy and creating databases. The aim of this study was to develop a comprehensive WHO-approved code system for gastrointestinal endoscopic terminology. The International Classification of Diseases, 10th edition (ICD-10), and the ICD-10 clinical modification (ICD-10-CM) were expanded to allow description of every possible gastrointestinal endoscopic term under conditions defined by the WHO. Classifications of specific gastrointestinal disorders and endoscopic locations were added. A new chapter was developed for frequently used terminology that could not be classified in the existing ICD-10, such as descriptions of therapeutic procedures. The new extended code system was named Gastrointestinal Endoscopic Terminology Coding (GET-C). The GET-C is a complete ICD-10-related code system that can be used within every endoscopic database program for all specific endoscopic terms. The GET-C is available for free at http://www.trans-it.org/.


World Journal of Gastroenterology | 2015

Intragastric band erosion: Experiences with gastrointestinal endoscopic removal

Edo O. Aarts; Bas van Wageningen; Frits J. Berends; Ignace Janssen; Peter J. Wahab; Marcel Groenen

AIM To remove the migrated bands using a gastrointestinal endoscopic approach. Little is published on complications that can occur. METHODS From June 2006 to June 2010, eight patients developed intragastric band migration. Two patients had received their AGB in a different hospital, the remaining six were operated by the same surgeon. In all patients gastrointestinal endoscopic removal of the band was attempted by two individual gastroenterologists. Clinical signs of band migration were: persisted nausea, abdominal pain, weight gain, recurrent infection of the port and tubing system and hematemesis. RESULTS In four patients removal was performed without complications. In two patients extracting the cleaved gastric band into the stomach appeared impossible. The two remaining patients presented with acute hematemesis and melena. One of these patients was readmitted with hematemesis. The other patient started bleeding during the gastroscopy and was converted to a laparoscopy in which one of the branches of the left gastric artery was oversewn. CONCLUSION Band migration after gastric banding can be life threatening. Gastrointestinal endoscopic removal is a feasible technique that holds the promise of fast reconvalescence.


Inflammatory Bowel Diseases | 2014

Naive T cells in the gut of newly diagnosed, untreated adult patients with inflammatory bowel disease.

Carmen S. Horjus Talabur Horje; Sabine Middendorp; Elly van Koolwijk; Lian Roovers; Marcel Groenen; Peter J. Wahab; Ellen G. van Lochem

Background:The phenotype of the T-cell subpopulations and their related cytokine networks in the gastrointestinal mucosa of patients with inflammatory bowel disease can potentially be used as a predictive value for clinical course and response to therapy. Here, we analyzed T-cell subpopulations in newly diagnosed, untreated adult patients and correlated them with clinical presentation. Methods:Mucosal biopsies from duodenum, ileum, and colon mucosa of patients with Crohns disease and ulcerative colitis and controls were obtained. The simple endoscopy score in Crohns disease and the full Mayo score in ulcerative colitis were used to score disease activity. Mucosa-infiltrating T cells were characterized by flow cytometric immunophenotyping and were stimulated to assess cytokine secretion. Results:Based on the expression of the maturation and activation markers CD45RA and CD27, we identified 4 different profiles. Profile A contained mainly CD45RA+CD27+ naive T cells; profile B contained mainly CD45RA−CD27+ central memory T cells; profile C contained mainly CD45RA−CD27− effector memory T cells; and profile D consisted of similar percentages of these aforementioned subpopulations. Profile A was only observed in the ileum/colon of patients with inflammatory bowel disease, associated with upper gastrointestinal location and perianal disease in Crohns disease and expressed more tumor necrosis factor &agr; and less interferon &ggr;. In contrast, profile D was restricted to controls. There was no correlation between the different T-cell profiles and endoscopic disease activity. Conclusions:Newly diagnosed patients with inflammatory bowel disease display different T-cell maturation profiles in the gut mucosa, corresponding to distinct cytokine responses. Follow-up studies are needed to determine whether the profiles associate with clinical course and response to therapy.


PLOS ONE | 2015

Contrast Enhanced Abdominal Ultrasound in the Assessment of Ileal Inflammation in Crohn's Disease: A Comparison with MR Enterography.

C. S. Horjus Talabur Horje; R. Bruijnen; L. Roovers; Marcel Groenen; F. B. M. Joosten; Peter J. Wahab

Background and Aims To prospectively examine the feasibility and accuracy of Contrast Enhanced Ultrasound (CEUS) in the assessment of Crohn’s disease (CD) activity in the terminal ileum in comparison to Magnetic Resonance Enterography (MRE), using endoscopy as a reference standard. Methods 105 consecutive patients with alleged clinically active CD were assessed by MRE and CEUS. CEUS of the terminal ileum was performed using an intravenous microbubble contrast enhancer. Accuracy values of CEUS and MRE for the presence of active terminal ileitis were evaluated using the Receiver Operating Characteristic method, using endoscopic findings as a reference standard. Sensitivity and specificity values of MRE and CEUS were compared by the McNemar test. Results CEUS was feasible in 98% of patients, MRE in all. Optimal diagnostic accuracy in CEUS was obtained at a peak intensity value of 10%, showing 100% sensitivity, 92% specificity and an accuracy of 99% in demonstrating ileal mucosal inflammation. For MRE, overall sensitivity, specificity and accuracy were, 87%, 100%, and 88%, respectively. CEUS and MRE were highly correlated in assessing length and wall thickness of the terminal ileum. CEUS identified 11 of 16 MRE-detected strictures, but no fistulae. Conclusion The accuracy of CEUS is comparable to that of MRE in the assessment of active, uncomplicated terminal ileal CD and therefore a valuable bedside alternative to MRE in the follow-up of these patients.


Inflammatory Bowel Diseases | 2016

Prevalence of Upper Gastrointestinal Lesions at Primary Diagnosis in Adults with Inflammatory Bowel Disease.

Carmen S. Horjus Talabur Horje; Jos W. R. Meijer; Lian Rovers; Ellen G. van Lochem; Marcel Groenen; Peter J. Wahab

Background:The prevalence of upper gastrointestinal (GI) involvement in adult inflammatory bowel disease has mostly been studied in patients with long-standing disease. The aim of this study was to prospectively evaluate the prevalence of upper GI involvement in a consecutive series of newly diagnosed, treatment-naive adult patients with inflammatory bowel disease, irrespective of upper GI tract symptoms. Methods:Consecutive patients with suspected inflammatory bowel disease underwent combined ileocolonoscopy and upper endoscopy with biopsies. Patients diagnosed with either Crohns disease (CD) or ulcerative colitis (UC), denying use of nonsteroidal anti-inflammatory drug, were included in the study. Helicobacter pylori infection was diagnosed histologically and positive patients were excluded from the analysis. Endoscopic and histologic lesions in the stomach and duodenum were recorded. Upper GI location (+L4) was defined as a combination of endoscopic and histological lesions. Results:A total of 152 patients (108 CD and 44 UC) were analyzed. Endoscopic lesions were only seen in patients with CD (60 of 108, 55%). Histological lesions were present in both patients with CD and patients with UC: focally enhanced gastritis in 58 CD (54%) and 10 UC (23%), granulomas in 30 CD (28%). Upper GI disease location was diagnosed in 44 patients with CD (41%) and no patients with UC. Upper GI tract symptoms were reported in 14 of 44 patients (32%) with upper GI location. Conclusions:A high prevalence of upper GI involvement was observed in newly diagnosed patients with CD, with a majority of the patients being asymptomatic. Focally enhanced gastritis was common in both patients with CD and patients with UC, whereas granulomatous inflammation was restricted to patients with CD.


Inflammatory Bowel Diseases | 2015

On naivety of T cells in inflammatory bowel disease: a review.

Carolijn Smids; Carmen S. Horjus Talabur Horje; Peter J. Wahab; Marcel Groenen; Sabine Middendorp; Ellen G. van Lochem

Abstract:Little is known about different phases of T-cell maturation in gut mucosa. Based on current knowledge about the migratory pathways of naive and memory T cells, it is believed that access to peripheral, nonlymphoid tissues is restricted to memory T cells. Surprisingly, there is increasing evidence of high numbers of naive T cells in the chronically inflamed gut tissue of patients with inflammatory bowel disease. This could partially be explained by new formation of ectopic lymphoid organs. Ongoing recruitment of naive T cells at inflammatory sites might play a role in the immunopathogenesis of inflammatory bowel disease.


Endoscopy | 2015

Acute pancreatitis as an adverse event in patients with the duodenal-jejunal bypass liner

Bark Betzel; Jens Homan; Edo O. Aarts; Ignace Janssen; Marcel Spanier; Peter J. Wahab; Marcel Groenen; Frits J. Berends

Placement of the duodenal-jejunal bypass liner (DJBL) is a minimally invasive technique for the management of patients with type 2 diabetes mellitus and obesity. Acute pancreatitis was seen in 5 of 167 patients (3 %) in our series. It is suggested that acute pancreatitis in patients with the DJBL results from either direct blockage or edema of the major duodenal papilla, which may be caused by the following: migration of the anchor of the DJBL, accumulation of food debris between the liner and the duodenal wall, or reflux of duodenal contents into the pancreatic duct due to intraluminal hypertension caused by the liner. Early removal of the DJBL resulted in fast and complete recovery, whereas delayed diagnosis and removal led to severe, necrotizing acute pancreatitis.

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Dive into the Marcel Groenen's collaboration.

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Peter J. Wahab

Erasmus University Rotterdam

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Carmen S. Horjus

Radboud University Nijmegen

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Ernst J. Kuipers

Erasmus University Rotterdam

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Arjun D. Koch

Erasmus University Medical Center

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Bark Betzel

Radboud University Nijmegen

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Bettina E. Hansen

Erasmus University Medical Center

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Dirk J. de Jong

Radboud University Nijmegen

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