Helicobacter pylori

In vitro effects of RBC against H pylori: Resistant strains of H pylori are increasingly recognized. In vitro data have shown that RBC is effective in killing 14 different strains of H pylori. The MIC90 of RBC against H pylori is 15 pg/mL to 16 pg/mL. Both in vitro and in a mouse model, the combination of RBC with clarithromycin resulted in a synergistic increase in the activity against H pylori strains, even in those resistant to clarithromycin. Osato et al, demonstrated in 10 of 11 H pylori isolates that clarithromycin MIC90 values could be reduced by ninefold, on average, when combined with RBC, and still achieve microbial killing. Thus, RBC and clarithromycin acted syner-gistically to overcome resistance to clarithromycin. In another in vitro study, RBC showed synergy with clarithromycin and tetracycline against both sensitive and resistant strains of the bacterium. The mechanism of synergy remains unknown. RBC combined with metronidazole in vitro also demonstrated either total or partial synergy against metronidazole-resistant strains. Choose a perfect online pharmacy to get cialis professional and treat your health issue.

In vitro emergence of antibiotic resistance: An in vitro study analyzed the emergence of resistance in H pylori strains subcultured with metronidazole and clarithromycin. Coculturing H pylori with RBC was found to reduce significantly the rate of emergence of resistance to metronidazole, more than clarithromycin; resistance to spiramycin was unaltered. Why this occurs is unknown; however, the authors observed that in the strain that showed a larger reduction in resistance, there was a higher density of bismuth molecules surrounding the H pylori organisms.