Role of Bismuth in the Eradication of Helicobacter pylori

Abstract

Bismuth salts exert their activity within the upper gastrointestinal tract through action of luminal bismuth. Bismuth exerts direct bactericidal effect on Helicobacter pylori by different ways: forms complexes in the bacterial wall and periplasmic space, inhibits different enzymes, ATP synthesis, and adherence of the bacteria to the gastric mucosa. Bismuth also helps ulcer healing by acting as a barrier to the aggressive factors and increasing mucosal protective factors such as prostaglandin, epidermal growth factor, and bicarbonate secretion. To date, no resistance to bismuth has been reported. Also synergism between bismuth salts and antibiotics was present. It was shown that metronidazole and clarithromycin resistant H. pylori strains become susceptible if they are administered together with bismuth. Bismuth-containing quadruple therapy was recommended both by the Second Asia-Pacific Consensus Guidelines and by the Maastricht IV/Florence Consensus Report as an alternative first choice regimen to standard triple therapy, in areas with low clarithromycin resistance, and it is recommended as the first-line therapeutic option in areas with a high prevalence of clarithromycin resistance. Greater than 90% eradication success can be obtained by bismuth-containing quadruple therapy. Choosing bismuth as an indispensable part of first-line therapy is logical as both metronidazole and clarithromycin resistances can be overcome by adding bismuth to the regimen.

Treatment of Helicobacter pylori in Special Patient Populations

“…Both bismuth salts and PPIs are active in vitro, whereas histamine H 2 ‐receptor antagonists (H 2 RAs) lack activity against H. pylori . Although the different bismuth salts vary in their in vitro activity, high concentrations achieved in the gastric lumen after oral administration may mitigate these differences, making all bismuth salts similarly efficacious . Of the various PPIs, lansoprazole and rabeprazole have the most potent antibacterial activity, and pantoprazole has the least .…”

Bismuth supplements as the first‐line regimen for Helicobacter pylori eradication therapy: Systemic review and meta‐analysis

“…Most bismuth compounds are insoluble in water, and the absorption rate is <0.5% . This explains the low rate of adverse events for taking bismuth, although abdominal pain, dark stool, dizziness, nausea, and a metallic taste have been previously reported.…”

“…In detail, only seven studies were published in the last 10 years, which is an already protracted period when dealing with H pylori therapy. Second, several studies enrolled were not standard triple therapy for H pylori eradication therapy, as Table mentioned. However, we performed subgroup analysis to evaluate the effectiveness of a bismuth add‐on to standard triple therapy, although the number of trials in the subgroup analysis was only 3.…”

“…Furthermore, it has antimicrobial activity, especially in cases of H pylori infection. The most striking points are that H pylori strains that are resistant to bismuth have not been reported, and bismuth is effective in treating cases with an established resistance to other antibiotics . We hypothesized that bismuth supplement as a first‐line regimen would be more beneficial and is effective on clarithromycin‐resistant H pylori .…”

“…The most striking points are that H pylori strains that are resistant to bismuth have not been reported, and bismuth is effective in treating cases with an established resistance to other antibiotics. 8,9 We hypothesized that bismuth supplement as a first-line regimen would be more beneficial and is effective on clarithromycin-resistant H pylori. To test this hypothesis, we evaluated the eradication rate of bismuth supplement to the firstline regimen for H pylori infection.…”