Double-blind comparison of absorbable colloidal bismuth subcitrate and nonabsorbable bismuth subnitrate in the eradication of Helicobacter pylori and the relief of nonulcer dyspepsia

A Review on the Recent Advancements on Therapeutic Effects of Ions in the Physiological Environments

This review focuses on the therapeutic effects of ions when released in physiological environments. Recent studies have shown that metallic ions like Ag+, Sr2+, Mg2+, Mn2+, Cu2+, Ca2+, P+5, etc., have shown promising results in drug delivery systems and regenerative medicine. These metallic ions can be loaded in nanoparticles, mesoporous bioactive glass nanoparticles (MBGNs), hydroxyapatite (HA), calcium phosphates, polymeric coatings, and salt solutions. The metallic ions can exhibit different functions in the physiological environment such as antibacterial, antiviral, anticancer, bioactive, biocompatible, and angiogenic effects. Furthermore, the metals/metalloid ions can be loaded into scaffolds to improve osteoblast proliferation, differentiation, bone development, fibroblast growth, and improved wound healing efficacy. Moreover, different ions possess different therapeutic limits. Therefore, further mechanisms need to be developed for the highly controlled and sustained release of these ions. This review paper summarizes the recent progress in the use of metallic/metalloid ions in regenerative medicine and encourages further study of ions as a solution to cure diseases.

Cost-Effectiveness of Empirical Bismuth-Based Quadruple Therapy and Tailored Therapy After Clarithromycin Resistance Tests for Helicobacter pylori Eradication

BACKGROUND

The eradication rate of clarithromycin-based standard triple therapy (STT) for Helicobacter pylori infection has decreased due to clarithromycin resistance (CR). We evaluated the cost-effectiveness of tailored therapy according to CR test results, and compared the results of STT with those of empirical bismuth quadruple therapy (BQT).

METHODS

The prospectively collected data of 490 H. pylori-positive patients with chronic gastritis or peptic ulcer disease were retrospectively analyzed. Among them, 292 patients underwent CR testing using dual-priming oligonucleotide-based polymerase chain reaction. The tailored group (n = 292) consisted of patients treated with STT for 7 days and BQT for 10 days as per their CR test results. The remaining patients were assigned to the empirical group (n = 198) and received BQT for 10 days without a CR test. The eradication rate, adverse events and medical costs associated with H. pylori eradication therapy were investigated.

RESULTS

In the tested patients (tailored group), the CR-positive rate was 32.2% (n = 94/292). The eradication rate according to an intention-to-treat analysis was 87.7% in the tailored group and 91.8% in the empirical group (P = 0.124); the respective rates were 94.4% and 97.9% by per-protocol analysis (P = 0.010). The frequency of adverse events was lower in the empirical group than the tailored group (35.1% vs. 52.7%, P < 0.001). Total per capita medical costs were $406.50 and $503.50, respectively.

CONCLUSIONS

Ten-day empirical BQT was more effective, safer, and less expensive than tailored therapy based on a CR test for H. pylori eradication.

A Novel Synthetic Compound, Bismuth Zinc Citrate, Could Potentially Reduce Cisplatin-Induced Toxicity Without Compromising the Anticancer Effect Through Enhanced Expression of Antioxidant Protein

Cisplatin is a common anticancer drug, but it comes with significant nephrotoxicity. Further cisplatin-induced oxidative stress contributes to the pathogenesis of the nephrotoxicity. A new compound, BiZn, can potentially prevent this complication. We verified our postulation by in vitro and in vivo models. From our findings, BiZn did not affect cisplatin-induced cytotoxicity on neuroblastoma cells under both in vitro and in vivo settings. However, BiZn significantly reduced the blood urea nitrogen and creatinine levels in cisplatin-treated mice. Under the lethal dosage of cisplatin, co-treatment of BiZn significantly increased the survival rate. BiZn stimulated antioxidant proteins metallothionein (MT) and glutathione (GSH) generation from kidney cells and minimized cisplatin-induced apoptosis. Knocking down MT-IIA and inhibiting GSH abolished such protection. In conclusion, pretreatment of BiZn decreased cisplatin-induced renal toxicity without affecting its antitumor activity. BiZn-induced antioxidant proteins MT and GSH may contribute to the renal protection effect.

Efficacy of bismuth-containing quadruple therapies for clarithromycin-, metronidazole-, and fluoroquinolone-resistant Helicobacter pylori infections in a prospective study

BACKGROUND & AIMS

We assessed the efficacy and safety of 4 bismuth-containing quadruple regimens as empiric therapies for Helicobacter pylori infections in patients who did not respond to previous treatment.

METHODS

We performed a prospective single-center study of 424 patients with H pylori infection that was not eradicated by previous therapies. Patients were assigned randomly to groups given lansoprazole (30 mg twice daily) and bismuth potassium citrate (220 mg twice daily), along with 500 mg tetracycline and 400 mg metronidazole 4 times daily (LBTM), 500 mg tetracycline and 100 mg furazolidone 3 times daily (LBTF), 1000 mg amoxicillin 3 times and 500 mg tetracycline 4 times daily (LBAT), or 1000 mg amoxicillin and 100 mg furazolidone 3 times daily (LBAF). Eradication was assessed by a (13)C-urea breath test. Antimicrobial susceptibility was assessed in 188 patients by the agar dilution method.

RESULTS

Per-protocol rates of H pylori eradication were greater than 90% for all regimens: 93.1% for LBTM (95% confidence interval [CI], 88.1%-98.0%), 96.1% for LBTF (95% CI, 92.4%-99.8%), 94.6% for LBAT (95% CI, 90.0%-99.2%), and 99.0% for LBAF (95% CI, 97.0%-100%). The intention-to-treat response rates were 87.9% for LBTM (95% CI, 81.7%-94.0%), 91.7% for LBTF (95% CI, 87.1%-96.3%), 83.8% for LBAT (95% CI, 76.8%-90.9%), and 95.2% for LBAF (95% CI, 91.1%-99.3%). Significantly more patients had infections eradicated by furazolidone-containing regimens than nonfurazolidone regimens (P = .01). Side effects occurred in 33.6% of subjects and occurred significantly more frequently in the LBTM group than the other 3 groups (vs LBTF, P = .006; vs LBAT, P = .003; vs LBAF, P = .02). Metronidazole resistance was 96.8%; no isolates were resistant to amoxicillin, tetracycline, or furazolidone.

CONCLUSIONS

Four bismuth-containing quadruple therapies achieved greater than 90% eradication of H pylori in patients who did not respond to previous treatment, including patients with metronidazole resistance. For patients allergic to penicillin, tetracycline and either metronidazole- or furazolidone-containing regimens are recommended. ClincialTrials.gov number, NCT01668927.

Multiple-antibiotic-resistant Helicobacter pylori infection eradicated with a tailor-made quadruple therapy

In 2008, a 44-year-old woman with mild epigastralgia diagnosed as having Helicobacter pylori-positive chronic gastritis without peptic ulcer underwent eradication therapy with lansoprazole (LPZ), amoxicillin (AMPC) and clarithromycin (CAM) for 7 days, but it failed, so treatment with rabeprazole, AMPC, and metronidazole (MNZ) for another 7 days was given, but it also failed. She was then prescribed a modified, 14-day sequential therapy of LPZ and AMPC with an increased dose of CAM followed by MNZ supplement, but the infection was still not eradicated. The H. pylori was cultured and examined for antibiotic susceptibility with the agar dilution method and was found to be resistant to CAM, MNZ, and levofloxacin, and non-sensitive to AMPC, namely multiple-antibiotic-resistant, although sensitive to minocycline. The CYP2C19 genotype of the patient was an extensive metabolizer (G681A: G/A, G636A: G/G). In 2010, she gave informed consent for a 14-day, tailor-made, modified classical (or modified high-dose PPI + AMPC) quadruple therapy comprising 30 mg LPZ, 500 mg AMPC and 500 mg bismuth subnitrate, qid, and 100 mg minocycline, bid. Two months later, her urea breath test was negative. Histology and bacterial culture were still negative 1 year after the therapy. She did not have any adverse events during or after the novel therapy, nor did she feel any further epigastralgia.

Adverse events with bismuth salts for Helicobacter pylori eradication: systematic review and meta-analysis

AIM

To assess the safety of bismuth used in Helicobacter pylori (H pylori) eradication therapy regimens.

METHODS

We conducted a systematic review and meta-analysis. MEDLINE and EMBASE were searched (up to October 2007) to identify randomised controlled trials comparing bismuth with placebo or no treatment, or bismuth salts in combination with antibiotics as part of eradication therapy with the same dose and duration of antibiotics alone or, in combination, with acid suppression. Total numbers of adverse events were recorded. Data were pooled and expressed as relative risks with 95% confidence intervals (CI).

RESULTS

We identified 35 randomised controlled trials containing 4763 patients. There were no serious adverse events occurring with bismuth therapy. There was no statistically significant difference detected in total adverse events with bismuth [relative risk (RR) = 1.01; 95% CI: 0.87-1.16], specific individual adverse events, with the exception of dark stools (RR = 5.06; 95% CI: 1.59-16.12), or adverse events leading to withdrawal of therapy (RR = 0.86; 95% CI: 0.54-1.37).

CONCLUSION

Bismuth for the treatment of H pylori is safe and well-tolerated. The only adverse event occurring significantly more commonly was dark stools.

Prevalence of Helicobacter pylori seropositivity among patients undergoing bariatric surgery: a preliminary study

BACKGROUND

The objective of this study was to compare the prevalence of Helicobacter pylori (HP) seropositivity in patients undergoing bariatric surgery with that of the general population.

METHODS

H. pylori serologies, tested by ELISA, were collected on 240 morbidly obese patients seen at the Cleveland Clinic Florida and on 2444 randomly selected patients seen at the Cleveland Clinic Health System from 2003-2005.

RESULTS

H. pylori prevalence was 61.3% in the bariatric surgery group versus 48.2% in the general population control group (p < 0.001). Bariatric patients had a 1.7-fold increased likelihood of having HP when compared with controls (95% CI = 1.3-2.2). Age over 35 years was an independent risk factor for HP seropositivity (p < 0.01) in both the bariatric and control groups. There was no association found between body mass index and seropositivity within the bariatric group. There was no significant association between seropositivity and gender (p = 0.776). However, there was a significant association between seropositivity and race (p < 0.01). African-Americans had four times more (OR = 4.05) probability of having HP seropositivity than Caucasians (p < 0.01). Hispanics had almost three times (OR = 2.6) more probability of having HP seropositivity than Caucasians (p < 0.01).

CONCLUSION

The prevalence of HP seropositivity among bariatric patients is significantly higher than the general population control group.

Adverse events with bismuth salts for Helicobacter pylori eradication: Systematic review and meta-analysis

AIM: To assess the safety of bismuth used in Helicobacter pylori (H pylori) eradication therapy regimens.

METHODS: We conducted a systematic review and meta-analysis. MEDLINE and EMBASE were searched (up to October 2007) to identify randomised controlled trials comparing bismuth with placebo or no treatment, or bismuth salts in combination with antibiotics as part of eradication therapy with the same dose and duration of antibiotics alone or, in combination, with acid suppression. Total numbers of adverse events were recorded. Data were pooled and expressed as relative risks with 95% confidence intervals (CI).

RESULTS: We identified 35 randomised controlled trials containing 4763 patients. There were no serious adverse events occurring with bismuth therapy. There was no statistically significant difference detected in total adverse events with bismuth [relative risk (RR) = 1.01; 95% CI: 0.87-1.16], specific individual adverse events, with the exception of dark stools (RR = 5.06; 95% CI: 1.59-16.12), or adverse events leading to withdrawal of therapy (RR = 0.86; 95% CI: 0.54-1.37).

CONCLUSION: Bismuth for the treatment of H pylori is safe and well-tolerated. The only adverse event occurring significantly more commonly was dark stools.

Review article: the treatment of refractory Helicobacter pylori infection

The occurrence of refractory Helicobacter pylori infection is increasing. When the bacteria are not eradicated it means that the antibiotics have not reached the gastric mucosa at a sufficient concentration and over a sufficient time lapse to kill them. The main reasons for this are poor patient compliance, resistant bacteria, low gastric pH and a high bacterial load. Therefore, when administering a new treatment, it is important to choose antibiotics which do not face resistance problems and which increase the dosage of antisecretory drugs and the duration of treatment and, if possible, to add a topical agent such as bismuth salt. The recommended empirical strategy is to prescribe quadruple therapy or, alternatively, 2-week triple therapy including amoxicillin-metronidazole, tetracycline-metronidazole or amoxicillin-rifabutin. However, when H. pylori is susceptible, clarithromycin can still be used. In the case of a high level of metronidazole resistance, furazolidone can be employed. In each case, it is important to ensure good patient compliance, and counselling is helpful in this regard. However, the best approach remains the prevention of refractory H. pylori infection and, for this purpose, antimicrobial susceptibility testing before first-line therapy is important and should be encouraged.

Is eradication of Helicobacter pylori with colloidal bismuth subcitrate quadruple therapy safe?

BACKGROUND

When standard triple therapy fails to eradicate Helicobacter pylori, quadruple 'rescue' therapy is often used which, in Europe, generally comprises colloidal bismuth subcitrate (CBS) based triple therapy and a proton pump inhibitor. Since hypochlorhydria could greatly increase absorption of the toxic bismuth ion from CBS, we investigated the bismuth status of patients receiving anti-H. pylori quadruple therapy.

MATERIALS AND METHODS

In a prospective open label study 34 patients with nonulcer dyspepsia or peptic ulcer disease, who had failed to eradicate H. pylori with standard triple therapy, were subsequently treated with CBS, omeprazole, amoxycillin and metronidazole (BOAM). A further 35 patients received triple therapy for the eradication of H. pylori: CBS, amoxycillin and metronidazole (BAM) (n = 18); placebo bismuth, amoxycillin and metronidazole (AM) (n = 9); or omeprazole, amoxycillin and metronidazole (OAM) (n = 8). Whole blood bismuth levels were determined before and within 24 hours of completing treatment. Analysis of bismuth was by inductively coupled plasma mass spectrometry, and concentrations were compared between groups and with the Hillemand 'alarm level' for blood bismuth (50-100 microg/l).

RESULTS

BOAM gave higher blood bismuth levels than BAM (difference in means 13.1, CI 6.0-20.2, p <.001); three (8.8%) patients taking BOAM had concentrations within the Hillemand alarm level at 54.2, 64.7 and 91.8 microg/l. OAM and AM did not alter baseline blood bismuth levels.

CONCLUSIONS

Caution should be observed in prescribing CBS with gastric acid suppression, and alternative bismuth preparations should be considered.