Ej van der Wouden

The influence of in vitro, nitroimidazole resistance on the efficacy of nitroimidazole-containing anti-Helicobacter pylori regimens : A meta-analysis

OBJECTIVES:The aim of this study was to determine the influence of nitroimidazole resistance (NIR) on the efficacy of treatment for Helicobacter pylori (H. pylori) infections by meta-analysis of the world literature.METHODS:A MEDLINE search, a manual search of all major gastroenterological journals from 1993 to 1997, and abstracts of gastroenterological and H. pylori meetings from 1993 to 1997 were performed. All treatment studies using a nitroimidazole and providing data about the medication used, dose frequency, total daily dose, duration of treatment, and eradication results in relation to NIR were included. Eradication had to be assessed by two biopsy-based tests or a urea breath test ≥4 wk after treatment. Individual studies were pooled into groups according to the medication used and the duration of treatment. The pooled estimate of the odds ratio (OR) of NIR for treatment failure and its 95% confidence interval (95% CI) were calculated for each group using the logit method. To detect any possible bias, funnel plots (plots of effect estimates against sample size) were constructed.RESULTS:A total of 91 treatment arms, including a total of 4823 patients, were evaluated. The pooled ORs of NIR for treatment failure (95% CI) of protonpump inhibitors, bismuth, and quadruple regimens were 5.2 (3.8–7.1), 5.9 (4.1–8.3), and 7.0 (3.1–16.0), respectively. Eradication rates were 90% in susceptible strains but <75% in resistant strains. In susceptible strains, neither treatment duration nor the choice of the second antibiotic influenced efficacy. In resistant strains, tetracycline was more effective than amoxicillin (bismuth regimens), and the longer the duration of regimens (bismuth-amoxicillin regimens) the more effective they were. Only quadruple regimens given for ≥1 wk were effective in resistant strains.CONCLUSIONS:NIR decreases treatment efficacy. Treatment duration and choice of other drugs influence the impact of NIR on treatment efficacy. If NIR is present, a nitroimidazole-containing regimen should be avoided or a quadruple regimen should be given for >1 wk.

The influence of metronidazole resistance on the efficacy of ranitidine bismuth citrate triple therapy regimens for Helicobacter pylori infection

: To assess the influence of metronidazole resistance on the efficacy of ranitidine bismuth citrate‐based triple therapy regimens in two consecutive studies.

One-week triple therapy with omeprazole, amoxycillin and tinidazole for Helicobacter pylori infection: the significance of imidazole resistance

Background: Triple therapy involving a proton pump inhibitor and two antibiotics has been suggested as an effective treatment for Helicobacter pylori infection. The impact of imidazole resistance on the efficacy of such regimens is largely unknown.

One-Week Triple Therapy With Ranitidine Bismuth Citrate, Clarithromycin and Metronidazole Versus Two-Week Dual Therapy With Ranitidine Bismuth Citrate and Clarithromycin for Helicobacter pylori Infection: A Randomized, Clinical Trial

Objective:The aim of this study was to compare the efficacy and side effects of 1-wk triple therapy with ranitidine bismuth citrate (RBC) 400 mg b.i.d., clarithromycin 500 mg b.i.d., and metronidazole 500 mg b.i.d., to 2-wk dual therapy with RBC 400 mg b.i.d. and clarithromycin 500 mg b.i.d. for H. pylori infection in a randomized, clinical trial.Methods:Patients (18–80 yr) with a culture proven H. pylori infection were randomized to one of these regimens. Side effects were scored on a semiquantitative scale. Endoscopy was performed ≥4 wk after treatment. Antral biopsy samples were taken for hematoxylin-eosin stain (HE), rapid urease test, and culture and corpus samples for culture and HE. Two weeks after the endoscopy, a 13C-urea breath test was performed. Eradication failure was defined as detection of H. pylori by culture or by at least two other tests.Results:A total of 104 patients, 54 men, age 54 ± 14 yr, (36 duodenal ulcer, 16 gastric ulcer, and 52 functional dyspepsia) were included. Gender, age, and diagnosis were comparable in both groups. Fourteen of 52 patients in both triple and dual therapy, respectively, had significant side effects, but all patients completed the course. Eradication results were 49 of 52 (94%; 95% CI: 84–99%) and 50 of 52 (96%; 95% CI: 87–100%) on intention to treat analysis and 44 of 46 (96%; 95% CI: 85–99%) and 48 of 49 (98%; 95% CI: 89–100%) on per protocol analysis for triple and dual therapy respectively.Conclusion:Both regimens are very effective and well tolerated in the treatment of H. pylori infection. The triple regimen has the advantage of being shorter.

Low cure rate of Helicobacter pylori infection with omeprazole and furazolidone dual therapy for one week

Furazolidone is an inexpensive antibiotic that has considerable anti‐Helicobacter pylori activity in vitro.

Implications of the simultaneous presence of metronidazole-susceptible and -resistant Helicobacter pylori colonies within a single biopsy specimen

Abstract This study examined whether the simultaneous presence of metronidazole-susceptible and -resistant Helicobacter pylori colonies in a single biopsy specimen is caused by a multiple strain infection with a susceptible and a resistant strain or by two subpopulations within a single strain. Single colonies obtained from seven biopsy specimens known to harbour both susceptible and resistant Helicobacter pylori were fingerprinted by restricted fragment length polymorphism typing of the ureC gene and by the random amplified polymorphic DNA procedure. Metronidazole susceptibility was determined by the E test. The results indicated that the occurrence of metronidazole-resistant and metronidazole-susceptible bacteria within a single biopsy does not imply the presence of a multiple strain infection with one resistant and one sensitive strain.

Six-year follow-up after successful triple therapy for Helicobacter pylori infection in patients with peptic ulcer disease

Objective & Design We question whether Helicobacter pylori eradication in peptic ulcer disease patients leads to a decrease in symptoms and reduced use of anti-dyspeptic drugs. Therefore, the recurrence rate of H. pylori, upper abdominal symptoms and the use of acid-suppressive drugs were determined 6 years after successful triple therapy. Methods Peptic ulcer disease patients successfully treated in 1990–1993 with ‘classic’ triple therapy were eligible. Patients were asked about symptoms and invited for a 13C-urea breath test or endoscopy in 1997–1998. Data on the use of anti-dyspeptic drugs were obtained from the pharmacy or general practitioner. Results Of the 113 eligible patients, 90 could be included in the study. The mean follow-up time was 6 years (range 4.6–7.6 years). H. pylori infection recurred in one patient (recurrence rate: 0.19% per patient-year; 95% confidence interval: 0.01–1.1%). Moderate or severe symptoms were experienced before therapy by 79% of the patients and after therapy by 18% of the patients (P< 10−7). Before triple therapy, 98% of the patients used H2-receptor antagonists and 54% were on maintenance treatment. After treatment, 30% used anti-dyspeptic medication and only 13% were on maintenance treatment (P < 10−7). Conclusions Six years after successful triple therapy in peptic ulcer disease patients, the recurrence rate of H. pylori infection is low and both symptoms and the use of anti-dyspeptic drugs have decreased significantly.