Jacob C. Thijs

The importance of vacA, cagA, and iceA genotypes of Helicobacter pylori infection in peptic ulcer disease and gastroesophageal reflux disease

OBJECTIVE:To study the relationship between the presence of H. pylori virulence factors and clinical outcome in H. pylori infected patients.METHODS:DNA was isolated from an antral biopsy sample and vacA, cagA, and iceA genotype were determined by PCR and a reverse hybridization technique in 183 patients with culture-proven H. pylori infection: 51 with peptic ulcer disease (PUD), 62 with gastroesophageal reflux disease (GERD), and 70 with a normal endoscopy (gastritis only; GO).RESULTS:Forty-four samples (24%) showed more than one allelic variant in the vacA s- or m-region and/or both iceA1 and iceA2 genotypes, indicating multiple strain infection. These were excluded from statistical analysis. vacA s1 and cagA were significantly more common in PUD than in GERD and GO. Logistic regression analysis showed that GERD patients were more often infected with strains lacking both cagA and iceA than GO patients (OR = 0.36; CI = 0.15–0.89). Trend analysis showed that GERD patients were most often infected with less virulent strains (p < 0.002).CONCLUSION:Multiple strain infection is common. H. pylori strains possessing the vacA s1 genotype and/or cagA are associated with PUD. GERD patients, infected with H. pylori, mostly carry less virulent strains possessing neither cagA nor iceA1. Our findings support the hypothesis that virulent strains protect against the development of GERD.

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.

Serology to monitor the efficacy of anti-Helicobacter pylori treatment

Objective. To assess the usefulness of monitoring anti-Helicobacter pylori antibodies to judge the efficacy of anti-Helicobacter treatment.Patients and methods. Twelve patients in whom eradication of H. pylori by triple therapy failed were compared with 24 successfully treated patients, matched for