BACKGROUND: Probiotics have never been used as second-line treatment in patients resistant to a first course of anti-H. pylori treatment. MATERIAL/METHODS: 70 consecutive patients with persistent H. pylori infection were enrolled and treated with ranitidine bismuth citrate (RBC) 400 mg b.d, esomeprazole or pantoprazole 40 mg/day, amoxycillin 1 g t.d, tinidazole 500 mg b.d. with (group A) or witlhout (group B) supplementation with 750 mg daily containing 16 billion bacteria Lactobacillus casei subsp. casei DG. Esomeprazole or pantoprazole 40 mg/day was administered for a further 4 weeks in cases of active peptic ulcer or severe gastritis detected at endoscopy. In these cases endoscopy was repeated one month after conclusion of therapy. The remaining patients were checked by 13C-urea breath test. RESULTS: Sixty-six patients completed the study, 34 in group A and 32 in group B. One group A patient (2.85%) was excluded for protocol violation and one group B patient (2.85%) was lost to follow-up. 33/34 group A patients were H. pylori-negative [per-protocol: 97.05%, on intention-to-treat: 94.28%]. 5/34 patients (14.7%) showed side-effects, but all of them completed the treatment. In group B, two patients (5.71%) showed severe side-effects and were withdrawn from the study. 30/32 patients were H. pylori-negative [per-protocol: 93.75%, on intention-to-treat: 85.71% (p = n.s.)]. 11/32 patients (34.37%) showed side-effects, but all of them completed the study (p < 0.05). CONCLUSIONS: This 10-day quadruple therapy obtains a high eradication rate, but probiotic supplementation reduces side-effects and permits a slight improvement in eradicating H. pylori.

Keywords: Anti-Bacterial Agents - adverse effects, Anti-Bacterial Agents - therapeutic use, Anti-Ulcer Agents - adverse effects, Anti-Ulcer Agents - therapeutic use, Drug Therapy, Combination, Gastrointestinal Diseases - drug therapy, Gastrointestinal Diseases - microbiology, Helicobacter Infections - complications, Helicobacter Infections - drug therapy, Helicobacter pylori, Lactobacillus casei, Probiotics - therapeutic use, Treatment Failure, Anti-Bacterial Agents - therapeutic use, Anti-Ulcer Agents - therapeutic use, Drug Therapy, Combination, Gastrointestinal Diseases - microbiology, Helicobacter Infections - drug therapy, Helicobacter pylori, Lactobacillus casei, Probiotics - therapeutic use, Treatment Failure