H. Pylori Infection Status (h + pylori_infection_status)

Distribution by Scientific Domains


Selected Abstracts


Effect of Helicobacter pylori infection on cyclooxygenase-2 expression in gastric antral mucosa

JOURNAL OF DIGESTIVE DISEASES, Issue 2 2002
Hong LU
OBJECTIVE: Helicobacter pylori infection is a major etiological cause of chronic gastritis. Inducible cyclooxygenase (COX-2) is an important regulator of mucosal inflammation. Recent studies indicate that expression of COX-2 may contribute to gastro­intestinal carcinogenesis. The aim of this study was to investigate the effects of H. pylori infection and eradication therapy on COX-2 expression in gastric antral mucosa. METHODS: Antral biopsies were taken from 46 H. pylori- infected patients, who also had chronic gastritis, both before and after anti- H. pylori treatment. The COX-2 protein was stained by using immunohistochemical methods and COX-2 expression was quantified as the percentage of epithelial cells expressing COX-2. Gastritis and H. pylori infection status were graded according to the Sydney system. RESULTS: Cyclooxygenase-2 expression was detected in the cytoplasm of gastric antral epithelial cells both before and after the eradication of H. pylori. Cyclooxygenase-2 expression in mucosa with H. pylori infection was compared with the corresponding mucosa after successful H. pylori eradication (20.1 ± 13.1%vs 13.8 ± 5.9%; P < 0.05). At the same time, COX-2 expression in H. pylori -infected mucosa was com­pared with the normal controls (18.0 ± 14.1%vs 12.3 ± 4.6%, P < 0.05). Expression of COX-2 was correlated with the degree of chronic inflammation (r= 0.78, P < 0.05). CONCLUSIONS: Our results showed that H. pylori infection leads to gastric mucosal overexpression of COX-2 protein, suggesting that the enzyme is involved in H. pylori -related gastric pathology in humans. [source]


Low-dose intravenous pantoprazole for optimal inhibition of gastric acid in Korean patients

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 9 2007
Jung-Hwan Oh
Abstract Background and Aim:, Proton-pump inhibitor (PPI) therapy for bleeding ulcers is more efficacious in Asian patients than in non-Asian patients. The aim of this study was to evaluate the efficacy of various doses of pantoprazole on intragastric acidity in Korean patients. Methods:, A prospective randomized study was conducted in 52 patients either with bleeding peptic ulcers after successful endotherapy or who received endoscopic mucosal resection for gastric neoplasms. Patients were randomized into two doses of intravenous pantoprazole: 40 mg q.d. and 40 mg b.i.d. We compared these results with our preliminary study utilizing high-dose pantoprazole (80 mg + 8 mg/h). The potential contribution of CYP2C19 genetic polymorphisms and the presence of Helicobacter pylori were also assessed. Results:, Pantoprazole 40 mg b.i.d. and high-dose pantoprazole demonstrated better inhibition of intragastric acid than pantoprazole q.d. (P < 0.05). The pantoprazole 40 mg q.d. group exhibited significant variations in acid inhibition correlating with CYP2C19 genotype. Median 24 h pH values did not differ significantly between the pantoprazole b.i.d. and high-dose pantoprazole groups, regardless of H. pylori infection status. A median intragastric pH < 6.0 was observed in only three of 28 patients in the 40 mg b.i.d. group; these three patients were extensive metabolizers. Conclusion:, A 40 mg b.i.d. dose of pantoprazole is sufficient to maintain pH > 6.0 in Korean patients, except for patients with extensive metabolizing CYP2C19 genotypes. [source]


Appropriate cut-off value of 13C-urea breath test after eradication of Helicobacter pylori infection in Japan

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 12 2003
CHIEKO KATO
Abstract Background and Aim:, A cut-off value of 2.5, for the 13C-urea breath test (UBT) is recommended in Japanese persons, based on the result of a multicenter trial in patients prior to treatment for eradication of Helicobacter pylori. The cut-off value of 2.5, has also been used in the assessment of eradication after treatment. The 6,8-week evaluation after treatment is recommended in the guidelines of the Japanese Society of Gastroenterology. The present study aimed to prospectively re-assess the cut-off value of the 13C-UBT at 6 weeks after treatment by using the results obtained at 6 months as an indication of true positive or true negative H. pylori infection status. Methods:, One hundred and ninety patients who were positive for H. pylori underwent eradication treatment, and 177 patients of these patients who were assessed as having true positive or true negative H. pylori,status ,at ,6 months ,after ,treatment ,were ,evaluated ,in ,this ,study. ,Eradication ,was ,assessed ,by 13C-UBT, ,culture, ,and ,histology ,at ,6 weeks ,and ,at ,6 months ,after ,treatment, ,and ,the ,cut-off ,value ,of 13C-UBT at 6 weeks was re-assessed. Results:, A cut-off value of 3.5,. at 6 weeks after treatment showed 97.2% diagnostic accuracy, while a cut-off value of 2.5, at 6 weeks showed 96.0% diagnostic accuracy. For a 3.5, cut-off value, only five patients were positive by 13C-UBT and were negative by culture and histology at 6 weeks, and three patients were true positive and two were false positive by the 13C-UBT at 6 months. Conclusion:, A cut-off value of 3.5, for the 13C-UBT is recommended at 6 weeks after eradication treatment in Japanese persons. [source]


Changes of gastric histology in patients with erosive oesophagitis receiving long-term lansoprazole maintenance therapy

ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 1 2010
M. M. Haber
Aliment Pharmacol Ther 2010; 32: 83,96 Summary Background, Changes in gastric histology associated with long-term maintenance therapy with lansoprazole for erosive oesophagitis have not been well described. Aim, To evaluate the effect on gastric histology of long-term dose-titrated lansoprazole administered as maintenance therapy for up to 82 months in patients with erosive oesophagitis. Methods, Sequential gastric biopsy specimens were obtained for evaluation of histological changes and Helicobacter pylori infection status. Results, Active and chronic inflammation improved from baseline to final visit in a majority of patients receiving long-term therapy with lansoprazole, irrespective of baseline H. pylori infection status. Reductions in active inflammation in the gastric body and antrum were seen in 53% (17/32) and 67% (20/30) of H. pylori -positive patients, respectively, and in 88% (7/8) and 86% (12/14) of H. pylori -negative patients, respectively. Reductions in chronic inflammation in the gastric body and antrum were seen in 38% (12/32) and 47% (15/32) of H. pylori -positive patients, respectively, and in 58% (70/121) and 57% (68/120) of H. pylori -negative patients, respectively. No clinically meaningful increases in hyperplasia, dysplasia, neoplasia, intestinal metaplasia or atrophy were observed during the follow-up period. Conclusions, Lansoprazole administered as maintenance therapy for up to 6 years in patients with erosive oesophagitis demonstrated gastric mucosal safety and was well tolerated. [source]


Clinicopathologic Comparison between the API2-MALT1 Chimeric Transcript-positive and -negative Gastric Low-grade B-Cell Lymphoma of Mucosa-associated Lymphoid Tissue Type

CANCER SCIENCE, Issue 6 2002
Tsuneya Nakamura
Little is known about the clinicopathological differences between API2-MALT1 chimeric transcript-positive and -negative gastric low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) type. The aim of this study was to clarify those differences in gastric MALT lymphoma. Twenty-three patients with gastric MALT lymphoma were enrolled in a unicenter study. Helicobacter pylori (H. pylori) infection status and clinical stages were investigated. Antibacterial treatment was performed for every patient. Responsiveness of MALT lymphoma to this treatment was assessed by means of regular follow-up endoscopy combined with biopsy. All cases were examined for API2-MALT1 chimeric transcript by means of RT-PCR and sequencing analyses. H. pylori infection status was assessed as positive in 20 patients and negative in three. With regard to responsiveness to antibacterial treatment, complete remission was observed in two patients, partial remission in 12 and no change in nine. API2-MALT1 chimeric transcript was detected in seven patients, all of whom showed no change in response to antibacterial treatment. API2-MALT1 positivity was found to be significantly correlated with responsiveness to antibacterial treatment (P=0.0001), absence of H. pylori infection (P=0.0198), and gross cobblestone mucosa observed endoscopically (P=0.0198). For the other factors (age, sex, dominant site of lesion, high-grade component, infiltrated layer of gastric wall, nodal involvement or clinical stages), there were no differences between API2-MALT1 chimeric transcript-positive and -negative cases. Gastric API2-MALT1 chimeric transcript-positive MALT lymphoma generally features unresponsiveness to antibacterial treatment, and is thought to be unrelated to H. pylori infection in its pathogenesis. Our findings indicate the presence of different clinical subtypes in gastric MALT lymphomas. [source]