DNA sequences and proteic antigens of H. pylori in cholecystic bile and tissue of patients with gallstones.

BACKGROUND: Although Helicobacter pylori DNA sequences have been detected in cholecystic bile and tissue of patients with gallstones, controversial results are reported from different geographic areas. AIM: To detect H. pylori in cholecystic bile and tissue of patients with gallstones from a previously uninvestigated geographic area, southern Italy. Detection included both the bacterial DNA and the specific antigen (H. pylori stool antigen) identified in the stools of infected patients for diagnostic purposes. PATIENTS AND METHODS: The study enclosed 33 consecutive patients undergoing laparoscopic cholecystectomy for gallstones. DNA sequences of H. pylori were detected by polymerase chain reaction in both cholecystic bile and tissue homogenate. Moreover, we assayed H.pylori stool antigen on gall-bladder cytosolic and biliary proteins after their extraction. Bacterial presence in the stomach was assessed by urea breath test in all patients and Deltadelta13CPDB value assumed as marker of intragastric load. Fisher's exact probability and Student's t-tests were used for statistical analysis. RESULTS: DNA sequences of H. pylori in bile were found in 51.5% and significantly correlated with its presence in cholecystic tissue homogenate (P<0.005), H. pylori stool antigen in gall-bladder (P=0.0013) and bile (P=0.04) proteins, gastric infection (P<0.01) and intragastric bacterial load (P<0.001). No correlation was found, however, with sex and age of the patients. CONCLUSIONS: Our prevalence value of bacterial DNA in bile and gall-bladder of patients with gallstones agreed with that of the only other Italian study. The simultaneous presence of both bacterial DNA and proteic antigen suggests that the same prototype of bacterium could be located at both intestinal and cholecystic level and, therefore, the intestine represents the source of biliary contagion.

The prolongation of triple therapy for Helicobacter pylori does not allow reaching therapeutic outcome of sequential scheme: a prospective, randomised study.

BACKGROUND AND AIM: One-week triple therapy for Helicobacter pylori revealed, during these last few years, a decrease in the eradication rate, so that the prolongation of its duration has been proposed. A sequential scheme recently showed very satisfactory results. We performed a prospective randomised study with the aim of either evaluating whether the triple therapy prolongation may improve its effectiveness and comparing its outcome with that of sequential regimen. PATIENTS AND METHODS: Three hundred and forty-two H. pylori positive patients completed the study. They were randomised to receive one of the following treatments: (i) a 7-day triple therapy comprising of rabeprazole (20 mg, b.i.d.) plus clarithromycin (500 mg, b.i.d.) and amoxycillin (1 g, b.i.d.); (ii) a 10-day triple therapy comprising the same scheme; (iii) a 10-day sequential regimen comprising of rabeprazole (20 mg, b.i.d.) plus amoxycillin (1 g, b.i.d.) for 5 days followed by rabeprazole (20 mg, b.i.d.) plus clarithromycin (500 mg, b.i.d.) and tinidazole (500 mg, b.i.d.) for the next 5 days. Therapeutic results were expressed using both intention-to-treat and per protocol analyses with 95% confidence intervals. A model of multivariate logistic regression analysis was performed using therapeutic outcome as a dependent variable and including endoscopic finding, smoking habit, age and sex as candidates for the model. RESULTS: Sequential regimen showed a significant gain in the eradication rate as compared to the 7-day (P < 0.0001) and the 10-day (P < 0.01) triple therapies, respectively. Overall eradication was lower in smokers than in non-smokers, but the difference remained significant only in the 7-day triple therapy (P < 0.01). Additionally, the overall eradication was higher in peptic ulcer than dyspepsia (P < 0.01), even if this difference was significant only for both triple therapies. CONCLUSIONS: Seven-day triple therapy achieves disappointing eradication rates in dyspeptics and smokers. Prolonging triple therapy to 10 days does not significantly improve the eradication rate. The novel 10-day sequential regimen is more effective and equally tolerated than the 10-day triple therapy.

Sequential treatment for Helicobacter pylori does not share the risk factors of triple therapy failure.

BACKGROUND: Predicting factors for the outcome of conventional Helicobacter pylori triple therapy have been identified. Of these, the presence of the CagA gene is a strong predictor of successful treatment. Our preliminary data show that this factor becomes irrelevant when sequential therapy is used. AIM: To identify predicting factors for the outcome of H. pylori eradication using two therapeutic schemes (triple and sequential) of equal duration (10 days). METHODS: Ninety-six patients with H. pylori infection were randomly assigned to receive one of the following therapeutic schemes: group A: rabeprazole (20 mg b.d.) plus amoxicillin (1 g b.d.) for 5 days, followed by rabeprazole (20 mg b.d.) plus tinidazole (500 mg b.d.) and clarithromycin (500 mg b.d.) for a further 5 days; group B: rabeprazole (20 mg b.d.) plus amoxicillin (1 g b.d.) and clarithromycin (500 mg b.d.) for 10 days. Age, sex, smoking, endoscopic and histological findings, and CagA and VacA status were considered as candidates for a model of multivariate analysis which used therapeutic outcome as the dependent variable. CagA and VacA status were assessed by polymerase chain reaction on DNA isolated from gastric antral specimens. RESULTS: The sequential scheme was significantly more effective than prolonged triple therapy (P < 0.05). Smoking (P < 0.001) and the absence of the CagA gene (P < 0.05) were significantly associated with the failure of triple therapy, but the effectiveness of sequential treatment was not predicted by these factors. CONCLUSION: Our data suggest that sequential therapy is not affected by bacterial and host factors which have, until now, predicted the outcome of conventional eradication treatments.