Background: Up to 35% of H. Pylori-positive patients remain infected after a first eradication attempt. Lactoferrin, a natural anti-bacterial glycoprotein, seems a promising tool in treating H. Pylori infection, but it has never been used in second-line treatment. Material/Methods: A prospective, randomized study was conducted on 70 consecutive patients with persistent H. Pylori infection after failure of the first standard treatment schedule. All patients were randomly treated with ranitidine bismuth citrate (RBC, 400 mg b.d.), esomeprazole (40 mg/day), amoxycillin (1 g t.d.), and tinidazole (500 mg b.d.) without (group A) or with (group B) supplementation of bovine lactoferrin (200 mg b.d.). One month after conclusion of therapy, endoscopy was performed in those patients for whom the examination was clinically relevant. The remaining patients were checked by (13)C-urea breath test. Results: Sixty-seven patients were fully compliant and completed the study (33, i.e. 94.28%, in group A and 34, 97.14%, 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. H. Pylori eradication was obtained in 31/33 (on intention-to-treat: 88.57%, 95%CI: 87-99%) group A patients and in 33/34 (on intention-to-treat: 94.28%, 95%CI: 86-100%) group B patients (p=ns). 16/68 patients (23.53%) experienced side effects (29.41% in group A and 17.64% in group B, p= 0.05). Conclusions: Lactoferrin supplementation was found effective in reducing side-effect incidence. Moreover, it seems capable of achieving a slight (and not statistically significant) improvement in eradicating H. Pylori when used in second-line treatment.

Keywords: Helicobacter Infections - drug therapy, Tinidazole - therapeutic use, Ranitidine - therapeutic use, Prospective Studies, Lactoferrin - therapeutic use, Helicobacter pylori, Anti-Bacterial Agents - therapeutic use, Esomeprazole - therapeutic use, Endoscopy, Gastrointestinal, Breath Tests, Bismuth - therapeutic use, Amoxicillin - therapeutic use