Bismuth salts with versus without acid suppression for Helicobacter pylori infection: A transmission electron microscope study

Rapid diagnosis and precision treatment of Helicobacter pylori infection in clinical settings

Helicobacter pylori is a gram-negative bacterium that colonizes the stomach of approximately half of the worldwide population, with higher prevalence in densely populated areas like Asia, the Caribbean, Latin America, and Africa. H. pylori infections range from asymptomatic cases to potentially fatal diseases, including peptic ulcers, chronic gastritis, and stomach adenocarcinoma. The management of these conditions has become more difficult due to the rising prevalence of drug-resistant H. pylori infections, which ultimately lead to gastric cancer and mucosa-associated lymphoid tissue (MALT) lymphoma. In 1994, the International Agency for Research on Cancer (IARC) categorized H. pylori as a Group I carcinogen, contributing to approximately 780,000 cancer cases annually. Antibiotic resistance against drugs used to treat H. pylori infections ranges between 15% and 50% worldwide, with Asian countries having exceptionally high rates. This review systematically examines the impacts of H. pylori infection, the increasing prevalence of antibiotic resistance, and the urgent need for accurate diagnosis and precision treatment. The present status of precision treatment strategies and prospective approaches for eradicating infections caused by antibiotic-resistant H. pylori will also be evaluated.

Bioactive Bismuth Compounds: Is Their Toxicity a Barrier to Therapeutic Use?

Bismuth compounds are considered relatively non-toxic, with their low solubility in aqueous solutions (e.g., biological fluids) being the major contributing factor to this property. Bismuth derivatives are widely used for the treatment of peptic ulcers, functional dyspepsia, and chronic gastritis. Moreover, the properties of bismuth compounds have also been extensively explored in two main fields of action: antimicrobial and anticancer. Despite the clinical interest of bismuth-based drugs, several side effects have also been reported. In fact, excessive acute ingestion of bismuth, or abuse for an extended period of time, can lead to toxicity. However, evidence has demonstrated that the discontinuation of these compounds usually reverses their toxic effects. Notwithstanding, the continuously growing use of bismuth products suggests that it is indeed part of our environment and our daily lives, which urges a more in-depth review and investigation into its possible undesired activities. Therefore, this review aims to update the pharmaco-toxicological properties of bismuth compounds. A special focus will be given to in vitro, in vivo, and clinical studies exploring their toxicity.

Helicobacter pylori infection

Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated. The infection affects around half of the population in the world but prevalence varies according to location and sanitation standards. H. pylori has unique properties to colonize gastric epithelium in an acidic environment. The pathophysiology of H. pylori infection is dependent on complex bacterial virulence mechanisms and their interaction with the host immune system and environmental factors, resulting in distinct gastritis phenotypes that determine possible progression to different gastroduodenal pathologies. The causative role of H. pylori infection in gastric cancer development presents the opportunity for preventive screen-and-treat strategies. Invasive, endoscopy-based and non-invasive methods, including breath, stool and serological tests, are used in the diagnosis of H. pylori infection. Their use depends on the specific individual patient history and local availability. H. pylori treatment consists of a strong acid suppressant in various combinations with antibiotics and/or bismuth. The dramatic increase in resistance to key antibiotics used in H. pylori eradication demands antibiotic susceptibility testing, surveillance of resistance and antibiotic stewardship.

The benefit of the bismuth add-on to the 2-week clarithromycin-based triple regimen for Helicobacter pylori eradication: a propensity score-matched retrospective study

BACKGROUND

Bismuth salt is bacteriostatic and bactericidal against Helicobacter pylori (H. pylori). Little is known about the benefit of bismuth itself. Recently in Korea, government regulation changed to allow bismuth add-on to conventional triple eradication regimens. Study aimed the additional benefit of the bismuth add-on to the 2-week clarithromycin-based triple regimen for H. pylori eradication.

METHODS

A single-centered retrospective review of electronic medical records was conducted in Seoul, Korea. Treatment-naïve H. pylori infected subjects treated with the clarithromycin-based triple regimen were consecutively enrolled. After propensity score matching, 118 subjects who were treated with rabeprazole 20 mg, amoxicillin 1 g, and clarithromycin 500 mg twice daily for 14 days (PAC) and matched 118 subjects with PAC plus bismuth subcitrate potassium 300 mg twice daily for 14 days (PACB) were included in the final analysis. The primary endpoint was the eradication success rates in each group.Article title: Kindly check and confirm the edit made in the article title.Yes, I agree with the article title.  RESULTS: The eradication success rates were 91.5% (86.4-96.6%) for PACB regimen and 81.4% (74.2-88.5%) for PAC in the intention-to-treat analysis, and 97.3% (94.2-100%) for PACB and 88.1% (81.9-94.3%) for PAC in the per-protocol analysis. The relative risk of eradication failure for PACB over PAC was calculated as 0.184 (0.0492-0688, p value = 0.005) in multiple regression logistic analysis. Compliance and adverse event incidence were not different between the two groups.Author names: Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 1 Given name: [Da Wit], Last name: [Shin]. Author 2 Given name: [Dae Young], Last name: [Cheung]. Author 3 Given name: [Ji Hee], Last name: [Song]. Author 4 Given name: [Fan Hee], Last name: [Lee]. Author 5 Given name: [Jin Il], Last name: [Kim]. Yes. I found the names presented are accurate and in the correct sequence. Author 1 Given name: [Da Wit], Last name: [Shin].Author 2 Given name: [Dae Young], Last name: [Cheung].Author 3 Given name: [Ji Hee], Last name: [Song].Author 6 Given name: [Han Hee], Last name: [Lee].Author 7 Given name: [Jin Il], Last name: [Kim].

CONCLUSION

The bismuth add-on to the 2-week clarithromycin-based triple regimen increased the eradication success rate.

Mass screening and eradication of Helicobacter pylori as the policy recommendations for gastric cancer prevention

Gastric cancer is an inflammation-related cancer triggered by Helicobacter pylori infection. Understanding of the natural disease course has prompted the hypothesis that gastric cancer can be prevented by administering a short-course antibiotic treatment to eradicate the H. pylori infection and interrupt this carcinogenic cascade. Results from randomized controlled trials and cohort studies have repeatedly confirmed this concept, which has moved attention from individual management of H. pylori infection to population-wide implementation of screening programs. Such a paradigm shift follows a three-tier architecture. First, healthcare policy-makers determine the most feasible and applicable eligibility, invitation, testing, referral, treatment, and evaluation methods for an organized screening program to maximize the population benefits and cost-effectiveness. Second, provision of knowledge and effective feedback to frontline general practitioners, including choice of diagnostic tests, selection of eradication regimens, and the indication of endoscopic examination, ensures the quality of care and increases the likelihood of desired treatment responses. Third, initiatives to raise population awareness are designed regarding the impact of H. pylori infection and risky lifestyle habits on the stomach health. These programs, with increased accessibility and geographic coverage in progress, will accelerate the decline in morbidity, mortality, and associated costs of this preventable malignancy.

The Influence of Past Metronidazole Exposure on the Outcome of Helicobacter pylori Eradication

Background

Bismuth quadruple therapy (BQT) is recommended as empirical first-line therapy because it is not affected by antibiotic resistance. We examined whether past exposure to metronidazole affected BQT outcomes.

Methods

The records of seven hospitals were searched for patients who received BQT for Helicobacter pylori eradication between 2009 and 2020. The association between past metronidazole exposure and the eradication rate was evaluated.

Results

This study was a multicenter retrospective study. Around 37,602 people tested for H. pylori infection were identified, and 7,233 received BQT. About 2,802 (38.7%) underwent a 13C-urea breath test to confirm eradication. The BQT efficacy was 86.4% among patients without metronidazole exposure and 72.8% among patients with exposure (p < 0.001). The eradication rate of BQT 14 days in patients with past exposure was higher than that of BQT <14 days (85.5 vs. 66.0%, p = 0.009). Multivariate analysis revealed that past metronidazole exposure [odds ratio (OR) 2.6, 95% CI 1.8–3.7; p < 0.001] and BQT <14 days (OR 1.5, 95% CI 1.2–2.0; p = 0.002) were independent risk factors for eradication failure.

Conclusion

Past metronidazole exposure significantly lowered the BQT eradication rate. BQT 14 days should be recommended for patients with suspected metronidazole exposure.