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Query: UMLS:C0038358 (gastric ulcer)
 5,179 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Diagnosis and successful eradication of Helicobacter pylori infection has been shown to be significantly related to symptom improvement in patients affected by chronic gastritis, duodenal and gastric ulcer. There is, therefore, an increasing need for the development of new, easy to use, reliable and non-invasive techniques to detect this organism. One such test is Flex-Sure (SmithKline Diagnostics Inc., United States), a new, rapid immunochromatographic test which requires a drop of the patient's serum to be placed on the absorbent pad of a strip. If specific antibodies to H. pylori are present a red colour line appears. The present study compared Flex-Sure with a homologous quantitative immunoenzymatic test (HM-CAP, EPI, US) using the same antigen (high molecular weight protein), the second generation GAP test (Bio-Rad, USA), a rapid urease test, culture and histology in a cohort of dyspeptic patients. We produced a semiquantitative visual scale with which to perform this comparison. Our results show that Flex-Sure possesses a sensitivity of 96.1%, a specificity of 73.9%, an overall accuracy of 78.8%, a positive predictive value of 72% and a negative predictive value of 91.6%. It showed a highly significant correlation with histological and cultural results (P < 0.001), and with the other serological tests (P < 0.0001). Based on our data we conclude that Flex-Sure may yield quick (within 4 min), simply readable, qualitative, and according to our colourimetric scale, even semiquantitative results. Furthermore, it does not require any sample dilution, any particular equipment, or any specialized training for the operator.
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PMID:Serodiagnosis of Helicobacter pylori: evaluation of a rapid, miniaturized immunochromatographic test. 785 77

In a prospective study 27 patients (13 women, 14 men; mean age 62 [45-83] years) with Helicobacter (H.) pylori associated disease received over 7 days pantoprazole (40 mg twice daily), clarithromycin (500 mg twice daily) and metronidazole (500 mg twice daily). Six patients had gastric ulcer, 4 duodenal ulcer, 4 erosive gastritis, 6 erosive duodenitis and 7 had H. pylori-positive functional dyspepsia. Pre-treatment oesophago-gastro-duodenoscopy was combined in 4 patients with antral and in 4 others with body-of-stomach biopsies to demonstrate H, pylori (urease test, specific culture and histology). The H. pylori status was checked with the 13C-urea breath test 4 weeks after the end of treatment. In addition, 9 patients with peptic ulcer were examined endoscopically at least 2 weeks after onset of the treatment to check for any healing of the ulcers, 25 of the patients completed the study according to the protocol. The H. pylori eradication rate was 100% (25 of 25 patients), while the "intention to treat" analysis gave a rate of 92.6% (25 of the 27 patients). The peptic ulcers were found to be healed in all 9 patients who had been endoscoped. One woman developed a reversible stomatitis, but the drug treatment did not have to be stopped. -These findings indicate that short-term triple treatment in the described manner is efficacious in curing H. pylori infection and any peptic ulcer. It is thus a highly promising treatment of H. pylori-associated diseases.
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PMID:[Short-term triple therapy with pantoprazole, clarithromycin and metronidazole for the healing of Helicobacter pylori infection]. 788 16

Helicobacter pylori (HP) is now recognized as a major etiologic agent of chronic gastritis and peptic ulcer and is recently presumed to be a cofactor in the occurrence of gastric cancer. HP has a high urease activity, which possibly plays a role in the pathogenesis of gastroduodenal diseases. In this paper, the function and the genetic structure of HP urease gene and the restriction fragment length polymorphism (RFLP) among HP strains using a probe of HP urease alpha subunit gene were described. HP urease gene cluster, which included structure genes, regulatory genes and accessory genes was identified and associated with the activity and the assembly. The RFLP pattern of HP tends to be distinct in gastric diseases, 460 bp pattern in gastric ulcer and 1,100 bp pattern in chronic gastritis, by Hae III digestion. HP showing a 460 bp RFLP pattern possessed a relatively high urease activity.
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PMID:[Polymorphism of Helicobacter pylori urease genes and gastric diseases]. 790 20

Helicobacter pylori (HP) in 41 patients (10 with stomach ulcer and 31 with duodenum ulcer) was found in gastro-biopsies from the stomach antrum before and after the treatment. The following methods to reveal HP were used: Giemsa staining, immunoperoxidase reaction with polyclonal monospecific antibodies against HP, urease rapid test. HP was also revealed in the blood serum by antibodies against HP by means of enzyme immunoassay. Electron microscopy was performed in 5 patients and bacteriologic study in 10 patients. Immunohistochemical method allows one to judge about real HP colonization of the gastric mucosa. Bacterioscopy with Giemsa staining gives good results but they are not true markers of HP presence this being explained by other methods. Serologic enzyme immunoassay gives an idea about the patient contamination, but not about HP eliminations as a result of treatment. Urease-test is adjuvant.
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PMID:[Diagnostic criteria of pyloric helicobacter infection in peptic ulcer]. 812 76

The in vitro effect of urea and hydrolysis of urea by urease on mucus H+ permeability is reported here. The effective DHCl values indicate a strong pH dependence for H+ diffusion in both water and mucus layers, with no apparent trend at concentrations between 1 and 50 mM urea. However, the estimated DHCl at near-neutral and alkaline pH are 4- to 10-fold lower through mucus than through aqueous films. Moreover, the pKa values of HCO3- and NH3 (generated by urease action on urea) had a profound effect on measured DHCl. These in vitro studies suggest that a high local concentration of NH3 and HCO3- within the mucus layer, generated by the action of Helicobacter pylori urease on endogenous intragastric urea, could greatly accelerate proton flux to the surface epithelium by operation of a buffer shuttle. This results in enhanced H+ permeability, particularly at pKa values of HCO3- and NH3, and in extreme circumstances it may result in gastric ulcer formation.
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PMID:An in vitro study of enhanced H+ diffusion by urease action on urea. Implications for Helicobacter pylori-associated peptic ulceration. 826 22

A prospective study of infection due to Helicobacter pylori in 104 Southern Appalachian veterans with upper gastrointestinal symptoms revealed a prevalence of 67%. There was no age difference observed between those with and without H pylori. The organism was shown to be present in 12 of 13 patients with duodenal ulcer (92%), 6 of 10 with gastric ulcer (60%), and 52 of 81 with nonulcer dyspepsia (64%). Using culture as standard, the urease test showed a sensitivity of 76% and specificity of 100%, while the biopsy stain had a sensitivity of 97%. The presence of acute inflammation in the antrum and body of the stomach closely correlated with the presence of the organism. Somewhat at variance with previous studies, our study indicated that H pylori in the body mucosa was strongly associated with chronic superficial gastritis with and without acute inflammation. Such a finding may reflect the natural history of infection due to H pylori and the advanced age of our patients.
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PMID:Chronic gastritis associated with infection due to Helicobacter pylori in southern Appalachian veterans with dyspepsia. 827 11

Since Helicobacter pylori is isolated very frequently from gastric ulcer specimens, the combination therapy of antimicrobial agent and proton pump inhibitor has recently been used. A study was made on whether cefdinir (CFDN), amoxicillin (AMPC), metronidazole (MNZ), omeprazole (OPZ), and omeprazole-M (OPZ-M) have antimicrobial activity against H. pylori and whether they can inhibit H. pylori-producing urease. 1) CFDN, AMPC and MNZ showed a potent antimicrobial activity against H. pylori, and especially, AMPC showed a marked bactericidal activity in a short time. 2) OPZ is reported to be converted to OPZ-M, and active form, in the body. OPZ and OPZ-M showed a moderate antimicrobial activity against H. pylori, and scarcely any bactericidal activity. 3) CFDN and OPZ or AMPC and OPZ in combination did not show any synergistic effect on the antimicrobial activity, but MNZ and OPZ in combination showed additive effect on the antimicrobial activity against H. pylori. 4) OPZ and OPZ-M inhibited H. pylori-producing urease and the inhibitory effect of OPZ-M was more stronger than that of OPZ. CFDN, AMPC and MNZ did not show any inhibitory effect on H. pylori-producing urease at 10 micrograms/ml. From these data, antimicrobial agents and proton pump inhibitors in combination are expected to exert the in vivo synergistic effect since these drugs eradicate H. pylori and inhibit H. pylori-producing urease.
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PMID:[Antibacterial activity of cefdinir and omeprazole against Helicobacter pylori and their inhibition on H. pylori-producing urease]. 840 93

The in vitro effect of ammonium bicarbonate buffer on mucus H+ permeability is reported here. The diffusional resistance of mucus and water was demonstrated to be dependent on buffer concentration, and the contrast between the two types of layers was most pronounced for low buffer concentration near neutrality. Moreover, the pKa values of HCO3- and NH3 had a profound effect on measured DHCl. These in vitro studies suggest that a potentially damaging high local concentration of NH3 and HCO3- within the mucus layer generated by the action of Helicobacter pylori urease on endogenous intragastric urea could greatly accelerate proton flux to the surface epithelium by operation of a buffer shuttle. This results in enhanced H+ permeability, particularly at pKa values of HCO3- and NH3, and that in extreme circumstances this may result in gastric ulcer formation.
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PMID:Enhanced H+ diffusion by NH4+/HCO3-: implications for Helicobacter-pylori-associated peptic ulceration. 851 85

Many diagnostic methods have been developed and used for detecting Helicobacter pylori to evaluate the success of treatment of H. pylori infection. We investigated and compared the suitability of the rapid urease test (RUT), polymerase chain reaction (PCR), 13C-urea breath test (13C-UBT), and serology with culture for evaluating cure of H. pylori infection. Forty-seven H. pylori-positive gastric ulcer patients received dual therapy of lansoprazole (30 mg u.i.d.) and clarithromycin (200 mg b.i.d.). Four weeks after the completion of treatment, RUT, PCR, 13C-UBT, and culture were performed and the negative rates of these tests were compared. Anti-H. pylori IgG antibodies were measured by enzyme-linked immunosorbent assay (ELISA) before and 4 weeks after completion of the treatment to evaluate changes of titers during the treatment. The negative rate of RUT (55%) was significantly greater than that of culture (27%). Significant declines in titers were seen in the patients who had negative culture results, while the decline in the titer was not significant in the patients who had positive results. PCR assay and 13C-UBT were suitable for the evaluation of H. pylori eradication, but RUT was not suitable, because of its sensitivity. By monitoring anti-H. pylori IgG antibody titers, therapeutic failure can be detected early after completion of treatment.
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PMID:Validity of various diagnostic tests to evaluate cure of Helicobacter pylori infection. 868 May 35

Helicobacter pylori are believed to play an important role in the formation of gastric ulcer in a syndrome characterized by a high urease activity. On the other hand, the production of oxygen radicals and platelet activating factor (PAF) is enhanced in gastric ulcers. The present study is designed to investigate the relationship between the different aspects of gastric mucosal injury, urease activity, oxygen radical production, and PAF content in gastric specimens. Biopsy specimens taken from 35 gastric ulcer patients were studied. Urease activity was detected by a rapid urease test (CLO). Oxygen radical production was measured as a value of luminol-dependent chemiluminescence (ChL) and PAF content was determined by radioimmunoassay in the biopsy samples. The CLO-positive rate was significantly higher in the gastric ulcer group in comparison with that in controls. ChL values and PAF content were significantly increased in gastric ulcers, especially in CLO-positive specimens. The CLO-positive rate, ChL values, and PAF content were also found to be increased at a distant site beyond the ulcer lesions. During the course of macroscopic ulcer healing of CLO-positive cases, the CLO positive level and the ChL values were not significantly decreased, although PAF content was significantly lower. Enhanced oxygen radical and PAF production were observed not only in the ulcer region but also at a distant site from the ulcer in the urease-positive gastric mucosa. The persistent enhancement of ChL values during the healing stage of urease-positive gastric ulcers suggests its involvement in the recurrence of gastric ulcers.
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PMID:Enhanced levels of chemiluminescence and platelet activating factor in urease-positive gastric ulcers. 872 Sep 17


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