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Duodenal Ulcer Disease (duodenal + ulcer_disease)
Selected AbstractsThe Helicobacter pylori plasticity region locus jhp0947,jhp0949 is associated with duodenal ulcer disease and interleukin-12 production in monocyte cellsFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2004Ramon De Jonge Abstract Colonization with Helicobacter pylori always results in chronic gastritis, which is controlled by infiltration of mononuclear cells and the subsequent release of cytokines like interleukin (IL)-12. To identify H. pylori factors involved in inducing cytokine production in mononuclear cells, a random H. pylori mutant library was screened for the inability to induce IL-12 production in monocyte THP-1 cells. Of the 231 random mutants screened, one mutant (M1) showed a consistent twofold decrease in the amount of IL-12 induction compared to the parental strain 1061 (P<0.01). Further characterization of mutant M1 revealed that the kanamycin resistance cassette had integrated in the jhp0945 gene, which is situated in an H. pylori strain-specific plasticity region. Three reference strains possessing this plasticity region induced significantly higher amounts of IL-12 when compared to the H. pylori 26695 reference strain, which does not possess this plasticity region. The role in disease outcome of jhp0945 as well as the neighbouring plasticity region genes jhp0947 and jhp049 was assessed in a Dutch population cohort. Firstly, the presence of jhp0947 was completely linked with that of jhp0949 and was roughly associated with jhp0945 (P=0.072), but not with the cag pathogenicity island (PAI) (P=0.464). The presence of the jhp0947 and jhp0949 genes, but not of jhp0945, was significantly associated with duodenal ulcer disease when compared to gastritis (P=0.027). Therefore, the jhp0947,jhp0949 locus may be a novel putative H. pylori marker for disease outcome independent of the cag PAI. [source] Disease-specific Helicobacter pylori Virulence Factors: The Unfulfilled PromiseHELICOBACTER, Issue S1 2000David Y. Graham A number of putative virulence factors for Helicobacter pylori have been identified including cagA, vacA and iceA. The criteria for a true virulence factor includes meeting the tests of biologically plausibility with the associations being both experimentally and epidemiologically consistent. Although disease-specific associations have been hypothesized/claimed, there are now sufficient data to conclusively state that none of these putative virulence factors have disease specificity. CagA has been claimed to be associated with increased mucosal IL-8 and inflammation, increased density of H. pylori in the antrum, duodenal ulcer (DU), gastric cancer, and protection against Barrett's cancer. Only the increase in IL-8/inflammation is direct and substantiated. Different H. pylori strains with functional cag pathogenicity islands do not vary in virulance as it has been shown that mucosal IL-8 levels are proportional to the number of cagA +H. pylori independent of the disease from which the H. pylori were obtained. It is now known that the density of either cagA + and cagA,H. pylori in the antrum of patients with H. pylori gastritis is the same. In contrast, the mean density of H. pylori in the antrum in DU is greater than in the antrum of patients with H. pylori gastritis. Of interest, the density of H. pylori is higher in the corpus of patients with H. pylori gastritis than those with DU, suggesting that acid secretion plays a critical role in these phenomena. The presence of a functional cag pathogenicity island increases inflammation and it is likely that any factor that results in an increase in inflammation also increases the risk of a symptomatic outcome. Nevertheless, the presence of a functional cag pathogenicity island has no predictive value for the presence, or the future development of a clinically significant outcome. The hypothesis that iceA has disease specificity has not been confirmed and there is currently no known biological or epidemiological evidence for a role for iceA as a virulence factor in H. pylori -related disease. The claim that vacA genotyping might prove clinically useful, e.g. to predict presentation such as duodenal ulcer, has been proven wrong. Analysis of the worldwide data show that vacA genotype s1 is actually a surrogate for the cag pathogenicity island. There is now evidence to suggest that virulence is a host-dependent factor. The pattern of gastritis has withstood the test of time for its relation to different H. pylori -related diseases (e.g. antral predominant gastritis with duodenal ulcer disease). The primary factors responsible for the different patterns of gastritis in response to an H. pylori infection are environmental (e.g. diet), with the H. pylori strain playing a lesser role. Future studies should work to eliminate potential bias before claiming disease associations. Controls must exclude regional or geographic associations related to the common strain circulation and not to the outcome. The authors must also control for both the presence of the factor and for the disease association. The study should be sufficiently large and employ different diseases and ethnic groups for the results to be robust. The findings in the initial sample (data derived hypothesis) should be tested in a new group (hypothesis testing), preferably from another area, before making claims. Finally, it is important to ask whether the results are actually a surrogate for another marker (e.g. vacA s1 for cagA) masquerading for a new finding. Only the cag pathogenicity island has passed the tests of biological plausibility (increased inflammation) and experimental and epidemiological consistency. [source] The risk of pancreatic cancer in patients with gastric or duodenal ulcer diseaseINTERNATIONAL JOURNAL OF CANCER, Issue 2 2007Juhua Luo Abstract Although Helicobacter pylori (H. pylori) seropositivity is linked to an excess risk of pancreatic cancer, the biologic mechanism is unknown. Gastric ulcer is primarily associated with corpus colonization of H. pylori, atrophic gastritis and formation of N -nitrosamines. Duodenal ulcer is a marker of antral colonization, hyperacidity and uninhibited secretin release. We estimated relative risks for pancreatic cancer among patients with gastric or duodenal ulcer, based on a register-based retrospective cohort study with 88,338 patients hospitalized for gastric ulcer and 70,516 patients for duodenal ulcer recorded in the Swedish Inpatient Register between 1965 and 2003. Following operation, the 14,887 patients who underwent gastric resection and 8,205 with vagotomy were analyzed separately. Multiple record-linkages allowed complete follow-up and identification of all incident cases of pancreatic cancer until December 31, 2003. Standardized incidence ratios (SIRs) estimated relative risks. During years 3,38 of follow-up, we observed a 20% excess risk (95% confidence interval [CI] 10,40%) for pancreatic cancer among unoperated gastric ulcer patients. The excess increased to 50% (95% CI 10,110%) 15 years after first hospitalization (p for trend = 0.03). SIR was 2.1 (95% CI 1.4,3.1) 20 years after gastric resection. Unoperated duodenal ulcer was not associated with pancreatic cancer risk, nor was vagotomy. Our results lend indirect support to the nitrosamine hypothesis, but not to the hyperacidity hypothesis in the etiology of pancreatic cancer. © 2006 Wiley-Liss, Inc. [source] Review article: Helicobacter pylori -negative duodenal ulcer diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 8 2009J. P. GISBERT Aliment Pharmacol Ther,30, 791,815 Summary Background,Helicobacter pylori infection rates in duodenal ulcer (DU) patients may be lower than previously estimated. Aim, To review the real prevalence of H. pylori -negative DUs and its possible causes. Methods, Bibliographical searches in MEDLINE looking for the terms ,H. pylori' and ,duodenal ulcer'. Results, Mean prevalence of H. pylori infection in DU disease, calculated from studies published during the last 10 years including a total of 16 080 patients, was 81%, and this figure was lower (77%) when only the last 5 years were considered. Associations with H. pylori -negative DU were: (1) False negative results of diagnostic methods, (2) NSAID use (21% in studies with <90% infection rate), (3) Complicated DU (bleeding, obstruction, perforation), (4) Smoking, (5) Isolated H. pylori duodenal colonization, (6) Older age, (7) Gastric hypersecretion, (8) Diseases of the duodenal mucosa, (9) Helicobacter,heilmanii' infection and (10) Concomitant diseases. Conclusion, In patients with H. pylori -negative DU disease, one should carefully confirm that the assessment of H. pylori status is reliable. In truly H. pylori -negative patients, the most common single cause of DU is, by far, the use of NSAIDs. Ulcers not associated with H. pylori, NSAIDs or other obvious causes should, for the present, be viewed as ,idiopathic'. True idiopathic DU disease only exceptionally exists. [source] Bleeding peptic ulcer , time trends in incidence, treatment and mortality in SwedenALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2009J. SADIC Summary Background, The incidence of peptic ulcer disease was expected to decrease following the introduction of acid inhibitors and Helicobacter pylori eradication. Aim, To analyse possible changes in the incidence of bleeding peptic ulcer, treatment and mortality over time. Methods, Residents of Malmö hospitalized for bleeding gastric or duodenal ulcer disease during 1987,2004 were identified in hospital databases (n = 1610). The material was divided into 6-year periods to identify changes over time. All patients who had been submitted to emergency surgery (n = 137) were reviewed. Results, The incidence rate for bleeding gastric or duodenal ulcers decreased by one half in males and by one-third in females and emergency operations decreased significantly (9.2%, 7.5% and 5.7% during the three time periods, respectively (P < 0.05). The post-operative mortality tended to decrease (9.7, 2.4 and 3.7%, respectively) and the 30-day mortality rates in the whole material were 1.2%, 3.6% and 3.4% during the different time periods. Conclusion, The incidence of bleeding gastric and duodenal ulcer disease has decreased markedly. Operative treatment has been replaced by endoscopic treatment. The bleeding ulcer-related mortality was less than 4% and has not changed over time. [source] Review article: should we kill or should we save Helicobacter pylori?ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 2001R.H. Hunt Results from epidemiological studies and therapeutic clinical trials have shown that Helicobacter pylori infection causes acute and chronic active gastritis and is the initiating factor for the majority of peptic ulcer disease. Eradication of the infection with antibiotics resolves gastritis and restores normal gastric physiology, accelerates healing of peptic ulcer disease, and virtually eliminates recurrence of duodenal ulcer disease. The infection also plays an important role in the initiation and/or progression of gastric atrophy and intestinal metaplasia, which may eventually lead to the development of distal gastric cancer. Furthermore, almost all patients with gastric MALT lymphoma are infected with H. pylori and cure of the infection leads to histological regression of the tumor and maintains the regression in over 80% of patients during long-term follow-up. Preliminary uncontrolled data from Japan show that eradication of the infection significantly reduced metachronous intestinal-type gastric cancer following initial endoscopic resection of early gastric cancer and might also prevent the progression of gastric adenoma to gastric dysplasia or gastric cancer. Although this overwhelming evidence has demonstrated that H. pylori infection is bad for humans, some have questioned the wisdom of eradicating the infection in all those infected. Their arguments are largely based on hypothesis and circumstantial evidence: 1) Less than 20% of all H. pylori infected persons will develop significant clinical consequences in their lifetime. 2) H. pylori strains are highly diverse at a genetic level and are of different virulence. 3) The antiquity of H. pylori infection in humans and their co-evolution suggests that H. pylori may be a commensal to humans. Eradication of H. pylori may remove some beneficial bacterial strains and may provoke esophageal disease or gastric cancer at the cardia. However, careful review of the literature confirms that H. pylori infection is a serious pathogen albeit in a minority of those infected. It remains for carefully designed prospective studies, rather than hypothesis to make changes in the current consensus position. [source] Triple therapy with clarithromycin, omeprazole, and amoxicillin for eradication of Helicobacter pylori in duodenal ulcer patients in Asia and AfricaALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 11 2000B. C. Y. Wong Background: Studies assessing the efficacy of triple therapy containing clarithromycin and amoxicillin for the eradication of Helicobacter pylori infection and healing of duodenal ulcers in Asian and African countries are limited. Aim: To determine the efficacy and safety of 1-week triple therapy with omeprazole, amoxicillin and clarithromycin for eradicating H. pylori infection in patients with active duodenal ulcer living in Asian and African regions. Methods: This was an open-label, multicentre study in 11 centres in Asia and Africa. Patients with endoscopy-proven duodenal ulcer and who were H. pylori -positive were treated with clarithromycin 500 mg, omeprazole 20 mg, and amoxicillin 1000 mg, all given twice daily for 7 days. Upper endoscopy was repeated at week 6 to check for ulcer healing and H. pylori status. Results: A total of 117 patients were recruited. H. pylori eradication rates were 85% by per protocol analysis and 80% by intention-to-treat analysis. Ulcer healing was found in 94% of subjects (per protocol analysis). Clinical success, measured by change of pre-treatment ulcer symptoms, was strongly supported by complete resolution or improvement in 100% of the evaluable patients (per protocol analysis). Since treatment-related adverse events, when present, were largely mild or moderate, the triple therapy regimen was considered safe. Conclusion: Seven-day triple therapy with omeprazole, amoxicillin, and clarithromycin was efficacious for treating Asian and African patients with duodenal ulcer disease associated with H. pylori infection, and the treatment regimen was well-tolerated. [source] The Nobel Prize in 2005 for the discovery of Helicobacter pylori: Implications for child healthACTA PAEDIATRICA, Issue 1 2006Rolf ZetterströmArticle first published online: 2 JAN 200 Abstract The Nobel Prize in Physiology or Medicine in 2005 has been awarded to B. Marshall and R. Warren for their discovery that peptic ulcer disease is caused by an infection with Helicobacter pylori. This infection, which affects about half of the world's population and is already extremely prevalent in adolescents in developing countries, starts as an asymptomatic gastritis which, under certain conditions, is followed by gastric or duodenal ulcer disease. Conclusion: No proven benefit has yet been found by treating H. pylori -infected children with gastritis unless they have a peptic ulcer. Vaccination against H. pylori infection during early childhood is considered a means of preventing peptic ulcer disease and also possibly adenocarcinoma. [source] | ||||||||||