Biomedical subjects

J H Kleibeuker

Publications and source records attributed to J H Kleibeuker.

At least 19 recordsLinked to original sources

PubMed2007

Effects of different immunosuppressive regimens on regulatory T-cells in noninflamed colon of liver transplant recipients.

BACKGROUND: Regulatory T-cells (Treg) are natural suppressors of autoimmunity. Previous studies indicate that immunosuppressive drugs, especially calcineurin-inhibitors, may interfere with Treg homeostasis. Inflammatory bowel disease (IBD) can relapse or develop de novo after liver transplantation. IBD is associated with a relative deficiency of Treg. The aim of this study was to determine the effect of long-term immunosuppression on the presence of Treg in the noninflamed colonic mucosa of liver transplant recipients. METHODS: Colonic biopsies of normal mucosa of 36 liver transplant recipients on different types of immunosuppression and 11 controls were studied. Treg marker Foxp3 and Treg products transforming growth factor-beta (TGF-beta) and interleukin-10 (IL-10) were studied by quantitative polymerase chain reaction (Q-PCR) and immunohistochemistry. TGF-beta-induced Smad-protein 3 and 7 were studied by Q-PCR. RESULTS: No significant differences between controls and patients were observed in IL-10, TGF-beta, and Smad expression. Mucosal Foxp3 mRNA levels and Foxp3+CD3+ cells were significantly reduced in transplant recipients using prednisone/azathioprine/tacrolimus compared with controls but no direct relationship between Foxp3 expression and 1 specific drug was detected. CONCLUSIONS: These results challenge the hypothesis that calcineurin-induced reduction of Treg or TGF-beta expression predisposes nontransplanted tissue to inflammation, but indicate that combined immunosuppression hampers Treg development in the intestine.

Adult↗

PubMed2006

[Screening the population for colorectal cancer: the background to a number of pilot studies in the Netherlands].

Colorectal cancer is one of the most common cancers in the Netherlands, where it is now the second most commonly-occurring cancer in terms of both incidence (10,000 new cases each year) and mortality rate (4,400 each year). - In 40% of all cases the disease is diagnosed at a late stage, which is associated with a poor outcome. - Research has shown that screening of the general population for colorectal cancer by means of the faecal occult blood test (FOBT) results in a reduction in mortality of approximately 16%. Whether endoscopic screening will result in a greater reduction in the mortality rate is currently under investigation. - This year, the first pilot study on implementation of screening for colorectal cancer using two different types of FOBT will start in the Netherlands.

Colorectal Neoplasms↗

PubMed2006

Increased risk of fundic gland polyps during long-term proton pump inhibitor therapy.

BACKGROUND: It is controversial whether proton pump inhibitor use leads to fundic gland polyp development. AIM: To determine whether fundic gland polyp development is due to proton pump inhibitor use and to investigate mechanisms involved. METHODS: Proton pump inhibitor use and the presence of fundic gland polyps were assessed in consecutive patients undergoing oesophagogastroduodenoscopy. Biopsies from fundic gland polyps and gastric mucosa were taken. Dysplasia was graded as negative, low or high grade. Prevalence of parietal cell hyperplasia and parietal cell protrusions and the proportional cystic area were assessed. RESULTS: 599 patients participated, 322 used proton pump inhibitors, 107 had fundic gland polyps. Long-term proton pump inhibitor use was associated with an increased risk of fundic gland polyps (1-4.9 years use: OR 2.2, 95% CI: 1.3-3.8; > or =5 years: OR 3.8, 95% CI: 2.2-6.7) while short-term therapy (<1 year) was not (OR 1.0, 95% CI: 0.5-1.8). Low-grade dysplasia was found in one fundic gland polyp. Fundic gland polyps associated with long-term proton pump inhibitor use had a larger proportional cystic area and higher frequency of parietal cell hyperplasia and parietal cell protrusion. CONCLUSIONS: Long-term proton pump inhibitor use is associated with an up to fourfold increase in the risk of fundic gland polyps. Risk of dysplasia is negligible. Aetiologically, these polyps seem to arise because of parietal cell hyperplasia and parietal cell protrusions resulting from acid suppression.

Adolescent↗

PubMed2006

CARD15 in inflammatory bowel disease and Crohn's disease phenotypes: an association study and pooled analysis.

BACKGROUND: Three major polymorphisms of the Caspase-Activation Recruitment Domain containing protein 15 gene have been described to be associated with Crohn's disease. Genotype-phenotype studies reported in literature provide conflicting data on disease localisation and behaviour. We investigated the relation of Caspase-Activation Recruitment Domain containing protein 15 with inflammatory bowel disease and Crohn's disease phenotypic characteristics in a large Dutch cohort and performed a pooled analysis on inflammatory bowel disease patients and Crohn's disease phenotypic characteristics reported in association studies. METHODS: We genotyped 781 cases and 315 controls for the R702W, G908R and 1007fsinsC variants and for six microsatellite markers in and close to Caspase-Activation Recruitment Domain containing protein 15. In the pooled analysis data of 7201 inflammatory bowel disease patients and 3720 controls from 20 studies were included. RESULTS: Association was found for Crohn's disease with R702W and 1007fsinsC, including several disease characteristics, and not for ulcerative colitis. In the pooled analysis all three common Caspase-Activation Recruitment Domain containing protein 15 variants showed strong association with Crohn's disease (p<0.00001; odds ratio varying from 3.0 for single heterozygotes to 14.7 for compound heterozygotes) and not with ulcerative colitis. Phenotype analysis showed association with small bowel involvement, stricturing and penetrating disease. CONCLUSION: Caspase-Activation Recruitment Domain containing protein 15 is associated with Crohn's disease and not with ulcerative colitis. All three common Crohn's disease-associated variants are associated with small bowel involvement, the G908R and 1007fsinsC alleles also being associated with a complicated disease course.

Adolescent↗

PubMed2006

What is the appropriate screening protocol in Lynch syndrome?

INTRODUCTION: Lynch syndrome families have a substantial risk of developing colorectal cancer (CRC). The recommended surveillance protocol includes colonoscopy every 2 years from age 20-25 years. It is yet unknown whether annual screening of patients aged 40-60 years is more effective than bi-annual screening, whether patients who had an adenoma removed should be re-examined after a year and whether surveillance of second-degree relatives is indicated. The aim of this study was to address these issues. METHODS: All carriers of a mismatch repair gene mutation who participated in the surveillance program were selected from the Dutch Lynch syndrome registry. The results of colonoscopy were prospectively collected. RESULTS: A total of 666 mutation carriers were identified in 110 families. Fourty-one CRCs were detected during endoscopic follow-up, of which 34 (83%) were diagnosed between age 40 and 60 years. In five of 34 patients, CRC was diagnosed within 1 year after colonoscopy, eight cancers were diagnosed between 1 and 2 years and the remaining tumors more than 2 years after colonoscopy. All eight CRCs detected between 1 and 2 years were at local stage. At least one adenoma was diagnosed at 141 examinations. The risk of developing CRC during follow-up in carriers with an adenoma was similar as in carriers without an adenoma at the previous colonoscopy. 280 parent-child couples with at least one Lynch syndrome-related carcinoma were identified in 110 families. In only 19 (6.8%) of these couples, CRC developed earlier in the child than an Lynch syndrome-associated cancer in the parent. CONCLUSION: The current surveillance protocol, i.e., bi-annual colonoscopy in first-degree relatives independent of age and endoscopic findings, appears to be appropriate.

Adenoma↗

PubMed2006

[Endoluminal treatment of gastro-oesophageal reflux disease: too early to determine a clear role].

Gastro-oesophageal reflux disease is a chronic disorder. The most important therapeutic measure is long-term pharmacological acid inhibition. Anti-reflux surgery plays a role in cases where pharmacological treatment fails. A new development is endoluminal treatment for reflux disorders. The various methods used are based on one of the following principles: radiofrequency ablation, gastroplication and implantation of a bulking agent. Short-term results with endoluminal treatment are not very positive and longer-term results have been disappointing so far. Results from randomised studies are still largely unavailable. Longer follow-up and controlled randomised studies are needed before a well-founded judgment can be made regarding the place of endoluminal treatment in the therapeutic armamentarium.

Antacids↗

PubMed2006

Identification of mismatch repair gene mutations in young patients with colorectal cancer and in patients with multiple tumours associated with hereditary non-polyposis colorectal cancer.

BACKGROUND: Patients with early-onset colorectal cancer (CRC) or those with multiple tumours associated with hereditary non-polyposis colorectal cancer (HNPCC) raise suspicion of the presence of germline DNA mismatch repair (MMR) gene mutations. AIM: To analyse the value of family history, microsatellite instability (MSI) analysis and MMR protein staining in the tumour to predict the presence of an MMR gene mutation in such patients. METHODS: In 281 patients diagnosed with CRC before the age of 50 years or with CRC and at least one additional HNPCC-associated cancer, germline mutation analysis in MLH1, MSH2 and MSH6 was carried out with denaturing gradient gel electrophoresis and multiplex ligation-dependent probe amplification. MSI analysis with five consensus markers and MMR protein staining for MLH1, MSH2 and MSH6 were carried out in the tumours. RESULTS: 25 pathogenic mutations (8 in MLH1, 9 in MSH2 and 8 in MSH6) were found. MSI analysis missed three and immunohistochemistry (IHC) missed two mutation carriers. Sensitivities of family history, MSI analysis and IHC for the presence of a mutation were 76%, 82% and 88%, specificities were 64%, 70% and 84%, and positive predictive values were 19%, 23% and 38%, respectively. Multivariate analysis showed the highest odds ratio for IHC (38.3, 95% confidence interval 9.0 to 184). Prevalence of pathogenic germline MMR gene mutations in patients with CRC before the age of 50 years was 6% and in those with > or =2 HNPCC-associated tumours was 22%. In the second group, no mutation carriers were found among the 29 patients who were diagnosed with their first tumour after the age of 60 years. CONCLUSION: Family history, MSI analysis and IHC are indicative parameters to select patients with CRC for MMR gene mutation analysis. The data show that IHC is the best single selection criterion.

Adaptor Proteins, Signal Transducing↗

PubMed2006

[Treatment of servere ulcerative colitis].

10-15% of patients with ulcerative colitis experience a severe episode of colonic inflammation that does not respond to mesalazine and oral corticosteroids. These patients require hospitalisation and treatment with intravenous corticosteroids. However, 25% of these patients do not respond to treatment. In these cases, intravenous cyclosporin is effective. Infliximab, an antibody against tumour necrosis factor alpha, is also beneficial. With these new treatment options, the colectomy rate in the acute phase has declined to about 35%. Other new therapies are under investigation in phase 2 and 3 trials. Surgery remains an important treatment option. Patients, gastroenterologists and surgeons should be involved in the clinical decision-making process.

Adrenal Cortex Hormones↗

PubMed2006

Novel approaches in the outpatient care of patients with chronic inflammatory bowel disease.

Treatment strategies for Crohn's disease are targeted toward lifelong management. Optimization of outpatient care is mandatory, because of many clinics facing capacity issues, and, along with routine follow-up of patients with inflammatory bowel disease, is putting increasing pressure on outpatient clinics. Recent studies demonstrate clearly that alternative management strategies are feasible and effective with a high rate of patient satisfaction. It is recommended that future research evaluates the way in which medical care is provided and explores the long-term effects of novel management strategies in IBD. This approach can then be extrapolated to other chronic conditions.

Ambulatory Care↗

PubMed2006

Inflammatory bowel disease after liver transplantation: risk factors for recurrence and de novo disease.

Inflammatory bowel disease (IBD) is associated with primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) and can recur or develop de novo after orthotopic liver transplantation (OLT). The aim of this study was to investigate the incidence and severity of IBD after liver transplantation and to perform a multivariate analysis for possible risk factors. In this retrospective study, 91 patients transplanted for PSC or AIH, without prior colectomy, were included. Sixty patients were transplanted for PSC, 31 for AIH. IBD activity before and after OLT and other possible risk factors were analysed in a multivariate model. Forty-nine patients (54%) had IBD before OLT. Forty patients (44%) had active IBD after transplantation: recurrence in 32 and de novo in 8. Cumulative risk for IBD after OLT was 15, 39 and 54% after 1, 5 and 10 years, respectively. In 59% of patients with IBD prior to OLT the disease was more active after transplantation. Risk factors for recurrent disease were: symptoms at time of OLT, short interval of IBD before OLT and use of tacrolimus. 5-aminosalicylates were protective. A cytomegalovirus positive donor/negative recipient combination increased the risk for de novo IBD.

Adult↗

PubMed2005

[The Nobel Prize in Physiology or Medicine for 2005 for the discovery of the stomach bacterium Helicobacter pylori].

This year, the Nobel Prize in Physiology or Medicine was awarded to the Australian doctors Marshall and Warren for their discovery and further identification of the stomach bacterium Helicobacter pylori. Thanks to their confidence in their own observations, we are now able to cure people with peptic-ulcer disease and low-grade gastric lymphoma and are potentially able to prevent gastric cancer.

Gastritis↗

PubMed2005

[Statins for the prevention of colorectal carcinoma: not yet recommended].

Statins are widely prescribed as lipid-lowering agents in the primary and secondary prevention of cardiovascular disease. They are increasingly associated with potential chemopreventive effects with respect to cancer. A recent case-control study reported a 47% relative reduction in the risk of colorectal cancer associated with statin use after adjustment for other known risk factors. There is evidence of an inhibitory effect of statins on colorectal carcinogenesis from in vitro studies, animal experiments, and observational and epidemiological reports in humans. Although statins seem promising as chemopreventive agents, it is still too early to recommend their use against colorectal cancer outside the context of clinical trials.

Case-Control Studies↗

PubMed2005

[More hereditary intestinal cancer can be detected if patients with colorectal carcinoma that are selected by the pathologist are examined for microsatellite instability].

OBJECTIVE: To determine whether an investigation of microsatellite instability (MSI) in patients with colorectal carcinoma that have been selected by the pathologist could increase the number of detected families with hereditary non-polyposis colorectal carcinoma (HNPCC). DESIGN: Prospective inventory. METHOD: Pathologists selected patients with a newly diagnosed colorectal carcinoma for MSI analysis of their tumour tissue if they met one of the following four criteria: (a) colorectal carcinoma diagnosed below 50 years of age; (b) a second colorectal carcinoma; (c) a combination of colorectal carcinoma and another HNPCC-related cancer; (d) colorectal adenoma with high-grade dysplasia diagnosed below 40 years of age. Patients with a positive MSI-test were referred to a clinical geneticist. The new strategy was introduced and explored in 5 hospitals for a period of to months. RESULTS: The new strategy was adopted and implemented successfully by pathologists and surgeons and accepted with satisfaction by the patients. Of the 55 patients included, 10 had a positive MSI-test. In 8/10 patients, DNA-mutation analysis was started by the clinical geneticist and 3 germline mutations in the MSH2-gene were detected. In 2 of 3 families with a pathogenic mutation, the family history alone did not fulfil the clinical criteria for HNPCC. CONCLUSION: Selection by the pathologist for MSI investigation was feasible in daily practice and identified more HNPCC patients than selection based on family history alone.

Adult↗

PubMed2005

[Screening for coeliac disease currently not indicated].

Coeliac disease is a common disorder, but most persons with coeliac disease remain undetected because they have only mild aspecific symptoms or are free of symptoms. For a definitive diagnosis small bowel biopsies showing partial or (sub)total villous atrophy are required. The presence of anti-endomysium and/or anti-tissue-transglutaminase antibodies in serum is strongly predictive for coeliac disease. In case of clear clinical suspicion the most straightforward way to diagnose or exclude coeliac disease is by taking endoscopic biopsies from the distal duodenum. When the suspicion is low, determination of the above mentioned antibodies as a first step suffices. At present there are insufficient reasons to initiate population-wide screening for coeliac disease by means of serological testing or individual screening by taking duodenal biopsies during each gastroscopy.

Antibodies, Anti-Idiotypic↗

PubMed2005

Review article: the potential of combinational regimen with non-steroidal anti-inflammatory drugs in the chemoprevention of colorectal cancer.

Non-steroidal anti-inflammatory drugs are chemopreventive agents in colorectal cancer. Non-steroidal anti-inflammatory drugs do not, however, offer complete protection against adenoma and carcinoma development. There is increasing interest in combining non-steroidal anti-inflammatory drugs with agents that target specific cell signalling pathways in malignant and premalignant cells. This review aims to describe the current knowledge regarding the efficacy of peroxisome proliferator-activated receptor-gamma ligands, cholesterol synthesis inhibitors (statins), epidermal growth factor signalling inhibitors and tumour necrosis factor-related apoptosis-inducing ligand against colorectal neoplasms and the rationale for combining these drugs with non-steroidal anti-inflammatory drugs to improve efficacy in the chemoprevention of colorectal cancer, a PUBMED computer search of the English language literature was conducted to identify relevant papers published before July 2004. Peroxisome proliferator-activated receptor-gamma ligands and statins, both in clinical use, reduce the growth rate of human colon cancer cells in vitro and in rodents models. In vitro, preclinical in vivo and clinical studies have shown efficacy of epidermal growth factor signalling inhibition in colorectal cancer. In vitro, tumour necrosis factor-related apoptosis-inducing ligand induces apoptosis in human colon cancer cells, but not in normal cells. These drugs have all been shown to interact with non-steroidal anti-inflammatory drugs in colorectal cancer cells and/or in rodent models. Combinational regimen are a promising strategy for the chemoprevention of colorectal cancer and should be further explored.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2005

Cost effectiveness of a new strategy to identify HNPCC patients.

BACKGROUND: Distinguishing hereditary non-polyposis colorectal cancer (HNPCC) from non-hereditary colorectal cancer (CRC) can increase the life expectancy of HNPCC patients and their close relatives. AIM: To determine the effectiveness, efficiency, and feasibility of a new strategy for the detection of HNPCC, using simple criteria for microsatellite instability (MSI) analysis of newly detected tumours that can be applied by pathologists. Criteria for MSI analysis are: (1) CRC before age 50 years; (2) second CRC; (3) CRC and HNPCC associated cancer; or (4) adenoma before age 40 years. METHODS: The efficacy and cost effectiveness of the new strategy was evaluated against current practice. Decision analytic models were constructed to estimate the number of extra HNPCC mutation carriers and the costs of this strategy. The incremental costs and gain in life expectancy for a HNPCC mutation carrier were evaluated by Markov modelling. Feasibility was explored in five hospitals. RESULTS: Using the new strategy, 2.2 times more HNPCC patients can be identified among a CRC population compared with current practice. This new strategy was found to be cost effective with an expected cost effectiveness ratio of 3801 per life year gained. When including the group of siblings and children, the cost effectiveness ratio became 2184 per life year gained. Sensitivity analysis showed these findings to be robust. CONCLUSIONS: MSI testing in a selection of newly diagnosed CRC patients was shown to be cost effective and a feasible method to identify patients at risk for HNPCC who are not recognised by family history.

Colorectal Neoplasms↗

PubMed2005

Expression of apoptosis related proteins during malignant progression in chronic ulcerative colitis.

BACKGROUND: Chronic ulcerative colitis (CUC) is associated with increased risk of developing colon cancer through a dysplasia (intraepithelial neoplasia)-carcinoma sequence. AIMS: To investigate the expression of apoptosis and inflammatory related proteins in CUC. METHODS: The expression of proteins involved in apoptosis and inflammation (inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), Bcl-xl, Fas, and active caspase 3) was investigated and compared with that seen in sporadic colon carcinoma. RESULTS: COX-2 was negative in the epithelium of all samples. iNOS was clearly present in inflammatory areas in CUC epithelium, weakly expressed in dysplasia, and absent or weakly expressed in tumour cells. Bcl-xl was absent in CUC, increased in dysplasia, and highly expressed in most carcinomas. Fas expression was positive in the surface epithelium of CUC, dysplasia, and most tumour cells. Activated caspase 3 was weakly positive in all samples, indicating limited apoptosis. Compared with CUC associated carcinoma, iNOS was consistently expressed in sporadic colon carcinoma cells, whereas Bcl-xl was almost absent in these tumour cells and Fas was only weakly expressed. Activated caspase 3 was present in normal mucosal samples and some tumour cells. CONCLUSION: Apoptosis related proteins--particularly iNOS, Bcl-xl, and Fas-show a distinct pattern of expression in the CUC to carcinoma sequence, which differs from that seen in sporadic carcinoma, but bears a striking resemblance to that seen during neoplastic progression in Barrett's oesophagus. These results support a causal role for chronic inflammation in cancer development in CUC, and treatment of ulcerative colitis should aim to minimise inflammation.

Adenocarcinoma↗

PubMed2005

Microscopic colitis: prevalence and distribution throughout the colon in patients with chronic diarrhoea.

BACKGROUND: Microscopic colitis presents with chronic diarrhoea with or without abdominal pain. Microscopic colitis is an important cause of chronic diarrhoea. It can be distributed throughout the colon, as well as limited to the right colon. Microscopic colitis is associated with coeliac disease. We studied the prevalence and distribution of microscopic colitis in patients with diarrhoea and normal colonoscopy and we studied the association with coeliac disease. METHODS: Colonoscopy was performed. Biopsies were taken from every segment of the colon. Lymphocytic colitis was defined as the presence of more than 20 lymphocytes per 100 epithelial cells and collagenous colitis was defined as thickening of the basal membrane of more than 10 microm. Upper endoscopy was performed if upper intestinal symptoms were present. If this was the case, small bowel biopsies were taken. RESULTS: Microscopic colitis was found in 13 out of 103 patients. The distribution was diffuse throughout the colon in ten and restricted to the right colon in three patients. In seven patients, upper endoscopy was performed. Marsh I/II lesions were found in six out of seven patients. CONCLUSION: Microscopic colitis was limited to the right colon in 23% of patients. Biopsies of macroscopically normal colonic mucosa in patients with diarrhoea is mandatory.

Adolescent↗