Bismuth absorption from 205Bi-labelled pharmaceutical bismuth compounds used in the treatment of peptic ulcer disease

Systematic Review and Meta-Analyses Assessment of the Clinical Efficacy of Bismuth Subsalicylate for Prevention and Treatment of Infectious Diarrhea

BACKGROUND

A large number of studies have evaluated the pharmacology, safety, and/or efficacy of bismuth subsalicylate for the relief of common gastrointestinal symptoms, diarrhea and vomiting due to acute gastroenteritis. In addition, short-term (48 h) medication with bismuth subsalicylate is known to be effective against infectious gastroenteritis such as travelers' diarrhea.

AIMS

Previous studies have documented the bacteriostatic/bactericidal effects of bismuth subsalicylate against a variety of pathogenic gastrointestinal bacteria. However, meta-analyses of the clinical efficacy of bismuth subsalicylate for both prevention and treatment of travelers' diarrhea have not yet been published.

METHODS

A total of 14 clinical studies (from 1970s to 2007) comprised the core data used in this assessment of efficacy of bismuth subsalicylate against infectious (including travelers') diarrhea. These studies allowed for statistical meta-analyses regarding prevention (three travelers' diarrhea studies) and treatment of infectious diarrhea (11 studies [five travelers' diarrhea]).

RESULTS

The results show that subjects treated with bismuth subsalicylate for up to 21 days have 3.5 times greater odds of preventing travelers' diarrhea compared with placebo (95% CI 2.1, 5.9; p < 0.001). In addition, subjects with infectious diarrhea treated with bismuth subsalicylate had 3.7 times greater odds of diarrhea relief (recorded on diaries as subjective symptomatic improvement) compared to those receiving placebo (95% CI 2.1, 6.3; p < 0.001).

CONCLUSIONS

This systematic review and meta-analysis suggests that bismuth subsalicylate can be beneficial for those at risk or affected by food and waterborne diarrheal disease such as traveler's (infectious) diarrhea, and may decrease the risk of inappropriate antibiotic utilization.

Addition of bismuth subnitrate to omeprazole plus amoxycillin improves eradication of Helicobacter pylori

OBJECTIVE

To evaluate whether the addition of bismuth subnitrate to a dual oral therapy regimen with omeprazole plus amoxycillin could improve Helicobacter pylori eradication.

METHODS

Fifty consecutive Helicobacter pylori-positive patients were randomly enrolled to receive either (A) bismuth subnitrate (300 mg q.d.s.), omeprazole (20 mg b.d.) and amoxycillin (500 mg q.d.s.), or (B) omeprazole (20 mg b.d.) and amoxycillin (500 mg q.d.s.). Both groups (n=25 each) received the medication for 14 days. H. pylori status was reassessed 30 days after completion of the therapy in order to evaluate eradication rates.

RESULTS

Six patients were lost to follow-up and therefore excluded from the study (three patients from each group). One patient from Group B withdrew from the study because of side-effects. The addition of bismuth subnitrate to omeprazole and amoxycillin significantly improved its efficacy in eradicating H. pylori, with 72% (18/25) eradication in Group A and 52% (13/25) in Group B (P=0.027). The addition of bismuth subnitrate to dual oral therapy was also capable of improving the healing of peptic ulcers when compared with dual oral therapy alone (100%, 8/8 vs. 58%, 4/7; P=0.021).

CONCLUSION

Our results demonstrate that the addition of bismuth subnitrate to dual oral therapy enhances H. pylori eradication, and improves healing of peptic ulcers.

Absorption of bismuth from several bismuth compounds during in vivo perfusion of rat small intestine

Evaluation of the amount of bismuth (Bi) absorbed from the gastrointestinal tract is important for assessment of the possible risks associated with the use of Bi compounds in the treatment of gastrointestinal disorders. We compared the absorption of Bi from media containing the equivalent of 1 g of elemental Bi from either Bi subnitrate (BSN), Bi subsalicylate (BSS), colloidal Bi subcitrate (CBS), Bi chloride (BiCl3), or Bi citrate (BCit) by an in vivo perfusion system of rat small intestine. The intestinal absorption was < 1% for all compounds, but higher from BCit and CBS than from BSN, BSS, and BiCl3. The dose dependency of Bi absorption from both CBS and BiCl3 in citrate buffer showed a nonlinear relationship between the concentration of Bi in perfusate and the concentration of Bi in blood after 60 min.

Quality of life and relapse of duodenal ulcer before and after eradication of Helicobacter pylori

BACKGROUND

The aim of the study was to compare relapse rates and quality of life before and after eradication of Helicobacter pylori in a group of patients with documented recurrent duodenal ulcer disease.

METHODS

Seventy-four patients with three endoscopically verified duodenal ulcers during the past 2 years received triple treatment consisting of bismuth subnitrate, oxytetracycline, and metronidazole for 14 days. Quality of life was measured with the Psychosocial Adjustment to Illness Scale (PAIS-SR) and H. pylori status with the 14C-urea breath test.

RESULTS

After triple treatment H. pylori was eradicated in 96%, and the ulcer was healed in all. Ulcer relapse was reduced from 100% before to 1.4% during a mean observation time of 111 weeks. The H. pylori reinfection rate was 2.4% during the 1st year. The patients were more satisfied with the health care system and had better sexual relationship and less psychologic distress 1 year after eradication of H. pylori than before.

CONCLUSIONS

For patients with recurrent duodenal ulcer, eradication of H. pylori with triple treatment leads to a significantly reduced ulcer relapse rate and improved quality of life.

Lack of evidence of neurotoxicity following 8 weeks of treatment with tripotassium dicitrato bismuthate

OBJECTIVE

To search for evidence of subclinical neurotoxicity in patients treated with tripotassium dicitrato bismuthate.

DESIGN

Prospective, controlled, triplicate study using urinary bismuth concentration, magnetic resonance imaging (MRI), nerve conduction studies, visual evoked response and a battery of 10 neuropsychological screening tests.

SETTING

Out-patient clinics, Walsgrave Hospital, Coventry, UK.

SUBJECTS

Fourteen dyspeptic patients; 8 (treatment group) treated with tripotassium dicitrato bismuthate one tablet q.d.s and 6 (control group) treated with ranitidine 150 mg b.d. for 8 weeks.

MAIN OUTCOME MEASURES

Changes in urinary bismuth, MRI, nerve conduction studies, visual evoked response, and neuropsychological tests performed before, immediately after and 8 weeks after the cessation of treatment.

RESULTS

In the treatment group the median (range) urinary bismuth concentration was 1 (1-12) ng/ml before treatment, increased to 560 (140-1300) immediately after treatment (P < 0.01, Wilcoxon Rank Sum test) and was still significantly elevated (23 (7-53) ng/ml) 8 weeks after the cessation of treatment. In the patient who recorded the highest urinary bismuth, a high intensity signal appeared in the globus pallidus immediately after treatment and was still present (though diminished in intensity) 8 weeks after the cessation of treatment. This isolated MRI finding was not associated with evidence of subclinical neurotoxicity. No changes in the MRI, nerve conduction studies, visual evoked response and neuropsychological tests were observed among the other patients studied.

CONCLUSIONS

Bismuth accumulation occurs in patients receiving a conventional course of treatment with tripotassium dicitrato bismuthate but this is not associated with significant changes in the nervous system.

205Bi/206Bi cyclotron production from Pb-isotopes for absorption studies in humans

Pb(p, xn) thick target excitation functions were measured in the energy range 10-38 MeV in order to optimize the production of isotopically pure radiobismuth from natPb, 206Pb, and 207Pb. Additionally, the decay of Po-isotopes from deuteron irradiation of natural bismuth (209Bi) was exploited for radiobismuth production. 205Bi was produced from 206Pb at 20 MeV with only 2% of 206Bi at 4 weeks post irradiation. Bismuth compounds as used in the treatment of peptic ulcer were labeled with 205Bi for absorption studies in animals and subjects.