Association of LEC and tnpA Helicobacter pylori genes with gastric cancer in a Brazilian population

<p>Abstract</p> <p>Background</p> <p><it>H. pylori </it>seroprevalence in Brazilians varies and is dependent on socioeconomic status, sanitation conditions and ethnicity; furthermore, <it>H. pylori </it>is not always associated with the incidence of gastric cancer, suggesting the role of more virulent strains. The purpose of this study was to analyze the association of more virulent <it>H. pylori </it>strains with gastric cancer.</p> <p>Methods</p> <p>DNA was extracted from gastric biopsies of thirty-four cases of gastric cancer (11 intestinal-type, 23 diffuse-type), and thirty-four of patients with endoscopic gastritis. The presence of <it>cag</it>PAI genes (<it>cagA</it>, <it>cagA </it>promoter, <it>cagE</it>, <it>cagM</it>, <it>tnpB</it>, <it>tnpA</it>, <it>cagT </it>and the left end of the <it>cag</it>II (LEC)) and <it>babA </it>were analyzed by PCR.</p> <p>Results</p> <p>Comparison of <it>H. pylori </it>isolates from gastric cancer and gastritis patients showed significant associations of <it>tnpA </it>and LEC with gastric cancer (73.5% [OR, 6.66; 95% CI, 2.30-19.25] and 58.8% [OR, 10.71; 95% CI, 3.07-37.28] of cases, respectively). Other <it>cag</it>PAI genes were detected in both groups at similar frequencies.</p> <p>Conclusions</p> <p><it>tnpA </it>and LEC of <it>H. pylori cag</it>PAI were associated with gastric cancer; nonetheless, these results were restricted within this group of patients and further studies are needed to confirm these results in a larger sample and determine their role in gastric carcinogenesis.</p

Efficacy of a 7-day course of furazolidone, levofloxacin, and lansoprazole after failed Helicobacter pylori eradication

<p>Abstract</p> <p>Background</p> <p>Increasing resistance to clarithromycin and nitroimidazole is the main cause of failure in the <it>Helicobacter pylori </it>eradication. The ideal retreatment regimen remains unclear, especially in developing countries, where the infection presents high prevalence and resistance to antibiotics. The study aimed at determining the efficacy, compliance and adverse effects of a regimen that included furazolidone, levofloxacin and lansoprazole in patients with persistent <it>Helicobacter pylori </it>infection, who had failed to respond to at least one prior eradication treatment regimen.</p> <p>Methods</p> <p>This study included 48 patients with peptic ulcer disease. <it>Helicobacter pylori </it>infection was confirmed by a rapid urease test and histological examination of samples obtained from the antrum and corpus during endoscopy. The eradication therapy consisted of a 7-day twice daily oral administration of lansoprazole 30 mg, furazolidone 200 mg and levofloxacin 250 mg. Therapeutic success was confirmed by a negative rapid urease test, histological examination and 14C- urea breath test, performed 12 weeks after treatment completion. The Chi-square method was used for comparisons among eradication rates, previous treatments and previous furazolidone use.</p> <p>Results</p> <p>Only one of the 48 patients failed to take all medications, which was due to adverse effects (vomiting). Per-protocol and intention-to-treat eradication rates were 89% (95% CI- 89%–99%) and 88% (88–92%), respectively. Mild and moderate adverse effects were reported by 41 patients (85%). For patients with one previous treatment failure, the eradication rate was 100%. Compared to furazolidone-naïve patients, eradication rates were lower in those who had failed prior furazolidone-containing regimen(s) (74% vs. 100%, p = 0.002).</p> <p>Conclusion</p> <p>An empiric salvage-regimen including levofloxacin, furazolidone and lansoprazole is very effective in the eradication of <it>Helicobacter pylori</it>, particularly in patients that have failed one prior eradication therapy.</p

Short-term triple therapy with azithromycin for Helicobacter pylori eradication: Low cost, high compliance, but low efficacy

<p>Abstract</p> <p>Background</p> <p>The Brazilian consensus recommends a short-term treatment course with clarithromycin, amoxicillin and proton-pump inhibitor for the eradication of <it>Helicobacter pylori </it>(<it>H. pylori)</it>. This treatment course has good efficacy, but cannot be afforded by a large part of the population. Azithromycin, amoxicillin and omeprazole are subsidized, for several aims, by the Brazilian federal government. Therefore, a short-term treatment course that uses these drugs is a low-cost one, but its efficacy regarding the bacterium eradication is yet to be demonstrated. The study's purpose was to verify the efficacy of <it>H. pylori </it>eradication in infected patients who presented peptic ulcer disease, using the association of azithromycin, amoxicillin and omeprazole.</p> <p>Methods</p> <p>Sixty patients with peptic ulcer diagnosed by upper digestive endoscopy and <it>H. pylori </it>infection documented by rapid urease test, histological analysis and urea breath test were treated for six days with a combination of azithromycin 500 mg and omeprazole 20 mg, in a single daily dose, associated with amoxicillin 500 mg 3 times a day. The eradication control was carried out 12 weeks after the treatment by means of the same diagnostic tests. The eradication rates were calculated with 95% confidence interval.</p> <p>Results</p> <p>The eradication rate was 38% per intention to treat and 41% per protocol. Few adverse effects were observed and treatment compliance was high.</p> <p>Conclusion</p> <p>Despite its low cost and high compliance, the low eradication rate does not allow the recommendation of the triple therapy with azithromycin as an adequate treatment for <it>H. pylori </it>infection.</p

Validation of a rapid stool antigen test for diagnosis of Helicobacter pylori infection

The aim of this study was to validate the rapid lateral flow Helicobacter pylori stool antigen test (One step H. pylori antigen test, ACON laboratories, San Diego, USA; Prime diagnostics, São Paulo), using 13C-Urea Breath Test as the gold standard for H. pylori infection diagnosis. A total of 98 consecutive patients, asymptomatic or dyspeptic, entered the study. Sixty-nine were women, with a mean age of 45.76 &plusmn; 14.59 years (14 to 79 years). In the H. pylori-positive group, the rapid stool antigen test detected H. pylori antigen in 44 of the 50 positive patients (sensitivity 88%; 95% CI: 75.7-95.5%), and six false-negative; and in the H. pylori-negative group 42 presented negative results (specificity 87.5%; 95% CI: 74.7-95.3%), and six false-positive, showing a substantial agreement (Kappa Index = 0.75; p O objetivo desse trabalho foi avaliar o teste rápido de antígeno de H. pylori nas fezes (One step H. pylori antigen test, ACON laboratories, San Diego, USA; Prime diagnostics, São Paulo), usando teste respiratório com uréia marcada com 13C (TRU-13C), como padrão ouro. Noventa e oito pacientes assintomáticos ou com dispepsia participaram do estudo. Sessenta e nove eram mulheres; a média de idade dos pacientes foi de 45.76 &plusmn; 14.59 (14 a 79 anos). No grupo H. pylori positivo, o teste rápido detectou antígenos de H. pylori nas fezes em 44 dos 50 pacientes positivos (sensibilidade de 88%; 95% IC: 75.7-95.5%), com seis falso-negativos; e no grupo H. pylori negativo, 42 apresentaram resultados negativos (especificidade de 87,5%; 95% IC: 74.7-95.3%), com seis falso-positivos, mostrando concordância substancial (índice Kappa = 0.75; p < 0.0001; 95% IC: 0.6-0.9). Quarenta e quatro dos 50 que tiveram teste de antígeno fecal positivo eram H. pylori positivos, sendo o VPP do teste 88% (95% IC: 75.7-95.5%), e 42 pacientes com teste de antígeno fecal negativo eram H. pylori negativos, com VPN de 87,5% (95% IC: 74.7-95.3%). Concluímos que o teste de antígeno fecal imunocromatográfico pode ser usado como alternativa ao teste respiratório para diagnóstico de infecção pelo H. pylori, principalmente em países em desenvolvimento

Peptic Ulcer [ulcera Peptica]

[No abstract available]55SPEC. IIS.127138Kurata, J.H., An assessment of nonsteroidal anti-inflammatory drugs as a risk factor in ulcer disease (1991) Ann Intern Med, 114, pp. 311-315Langman, M.J.S., Epidemiologic evidence on the association between peptic ulceration and anti-inflammatory drug use (1989) Gastroenterology, 96 (2), pp. 640-646Kurata, J.H., Abbey, D.E., The effect of chronic aspirin use on duodenal and gastric ulcer hospitalizations (1990) J Clin Gastroenterolog, 12, pp. 260-266Zaterka, S., Eisig, J.N., Chinzon, D., Gastrinoma. Diagnóstico e tratamento (1993) GED, 1, pp. 7-14Vaira, D., Menegatti, M., Miglioli, M., What is the role of Helicobacter pylori in complicated ulcer disease? 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Comparison with cimetidine (1991) Dig Dis Sci, 36 (10), pp. 1377-1381Helicobacter pylori infection in peptic ulcer disease (1994) Jama, 272, pp. 65-69Forbes, G.M., Glaser, M.E., Cullen, J.E., Duodenal ulcer treatment with Helicobacter pylori eradication. Seven-year follow up (1994) Lancet, 1, pp. 258-260Graham, D., Lew, G., Klein, P., Effect of treatment of Helicobacter pylori infection on the long-term recurrence of gastric or duodenal ulcer (1992) Ann Intern Med, 116, pp. 705-708Tytgat, G.N.J., Noach, L.A., Rauws, E.A.J., Helicobacter pylori infection and duodenal ulcer disease (1993) Gastroenterol Clin North Am, 22, pp. 127-139Zaterka, S., Eisig, J.N., Sadowski, E., Chinzon, D., Is Helicobacter Pylori Reinfection Rate Really Higher in Developing Countries? 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Philadelphia, WB SaundersBianchi-Porro, G., Barbara, I., Cheli, R., Comparison of tripotassium dicitrato bismuthate (TDB) tablets and ranitidine in the healing and relapse of duodenal ulcer (1984) Proc LiverpoolParente, F., Lazzaroni, M., Petrillo, M., Bianchi-Porro, G., Colloidal bismuth subcitrate and ranitidine in the short-term treatment of benign gastric ulcer (1986) Scand J Gastroenterol, 21 (122 SUPPL.), pp. 42-45Barbara, L., Corinaldesi, R., Rea, E., The role of colloidal bismuth subcitrate in the short-term treatment of duodenal ulcer (1986) Scand J Gastroenterol, 21 (122 SUPPL.), pp. 30-34Hamilton, I., Wormsley, B.W., O'Connor, H.J., Axon, A.T.R., Effects of tripotassium dicitrato bismuthate (TDB) tablets or cimetidine in the treatment of duodenal ulcer (1983) Gut, 24, pp. 1148-1151Coste, T., Rautureau, J., Beaugrand, M., Comparison of two sucralfate dosages presented in tablet form in duodenal ulcer healing (1987) Am J Med, 83 (SUPPL. 3B), pp. 86-90Gorbach, S.L., Bismuth therapy in gastrointestinal diseases (1990) Gastroenterology, 99, pp. 863-875Dammann, H.G., Dreyer, M., Muller, K.P., Simon, B., First-choice treatment in uncomplicated ulcer disease: A case for acid inhibitors (1988) Scand J Gastroenterol, 23 (153 SUPPL.), pp. 62-70Walan, A., A review of the clinical experience with omeprazole (1988) Ital J Gastroenterol, 20 (SUPPL.), pp. 35-38Walan, A., Bader, J.P., Classen, M., Effect of omeprazole and ranitidine on ulcer healing and relapse rates in patients with benign gastric ulcer (1989) N Engl J Med, 320, pp. 69-75Bate, C.M., Wilkinson, S.P., Bradby, G.V.H., Randomised, double blind comparison of omeprazole and cimetidine in the treatment of symptomatic gastric ulcer (1989) Gut, 30, pp. 1323-1328McFarland, R.J., Bateson, M.C., Green, J.R.B., Omeprazole provides quicker symptoms relief and duodenal ulcer healing than ranitidine (1990) Gastroenterology, 98, pp. 278-283Valenzuela, J.E., Berlin, R.G., Snape, W.J., US experience with omeprazole in duodenal ulcer. 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(1990) Gastroenterology, 99, pp. 345-351Mignon, M., Hochlaf, S., Forestier, S., Effet dose-response du lansoprazole chez des malades atteints d'un syndrome de Zollinger-Ellison (1994) Gastroenterol Clin Biol, 18, pp. 13-16Andersson, T., Regardh, C.G., Dahl-Puustinen, M.L., Bertilsson, L., Slow omeprazole metabolizers are also poor S-mephenytoin hydroxilators (1990) Ther Drug Monit, 12, pp. 415-416Andersson, T., Regardh, C.G., Lou, Y.C., Polymorphic hydroxilation of S-mephenytoin and omeprazole metabolism in Caucasian and Chinese subjects (1992) Pharmacogenetics, 2, pp. 25-31Steinijans, V.W., Huber, R., Hartmann, M., Lack of pantoprazole drug interactions in man (1994) Intern J Pharmacol Ther, 32, pp. 385-399Arnold, R., Koop, H., Omeprazole: Long-term safety (1989) Digestion, 44 (1 SUPPL.), pp. 77-86Jensen, R.T., Metz, D.C., Koviack, P.D., Feigenbaum, K.M., Prospective study of the long-term efficacy and safety of lansoprazole in patients with the Zollinger-Ellison syndrome (1993) Aliment Pharmacolog Ther, 7 (1 SUPPL.), pp. 41-50Zaterka, S., Inibidores da bomba de prótons (IBPs): Tolerabilidade esegurança (1998) GED, 17, pp. 153-157Festen, H.P.M., Prevention of duodenal ulcer relapse by long-term treatment with omeprazole (1994) Scand J Gastroenterol, 29 (201 SUPPL.), pp. 39-41Eriksson, S., Langström, G., Rikner, L., Omeprazole and H2-receptor antagonists in the acute treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis: A meta-anlysis (1995) Eur J Gastroenterol Hepatol, 7, pp. 467-475Hunt, R.H., Peptic ulcer diseases: Defining the treatment strategies in the era of Helicobacter pylori (1997) Am J Gastroenterol, 92, pp. 36S-43SHowden, C.W., Optimizing the pharmacology of acid control in acid-related disorders (1997) Am J Gastroenterol, 92, pp. 17S-21SHoskimg, S.W., Ling, T.K.W., Chung, S.C.S., Duodenal ulcer healing by eradication of Helicobacter pylori without anti-acid treatment: Randomized controlled trial (1994) Lancet, 343, pp. 508-510Logan, R.P.H., Gummett, P.A., Misiewicz, J.J., One week's anti-Helicobacter pylori treatment for duodenal ulcer (1994) Gut, 35, pp. 15-18Zaterka, S., Eisig, J.N., Chinzon, D., Five day X tem day triple therapy (amoxacillin, furazolidone and metronidazole) in the treatment of duodenal ulcer and H. pylori erradication. 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