Antimicrobial therapy of peptic ulcers

Efficacy and Safety of Standard Triple Therapy for Helicobacter pylori Eradication in Latin America : A Systematic Review and Meta-Analysis

GOALS

To evaluate the efficacy and safety of standard triple therapy (STT) in Latin America.

BACKGROUND

Helicobacter pylori infection affects more than 50% of the Latin Americans and leads to gastric mucosa damage. Scarce data on effective therapeutic approaches in the region underscores the need for comprehensive information.

STUDY

The analysis included Randomized Controlled Trials published up to the year 2020, comparing STT with other treatments. Cumulative relative risks (RR) were estimated, with 95% CI, according to intention-to-treat (ITT) and per protocol (PP) analysis.

RESULTS

Eleven studies (clinical trials conducted between 1995 and 2013), revealed cumulative eradication rates of 78.31-90.63% (ITT) and 76.71-93.55% (PP). The eradication with the STT was superior to sequential therapy (ITT-RR: 10.6, 95% CI: 1.01 to 1.12) (PP-RR: 10.6, 95% CI: 1.02-1.11) and dual therapy (ITT-RR: 1.61, 95% CI: 1.13-2.30) (PP-RR: 1.72, 95% CI: 1.25-2.37), but is less effective than other triple therapies (PP-RR: 0.85, 95% CI: 0.78-092). Regarding adverse effects, diarrhea, metallic taste, nausea, vomiting, and headache were the most common symptoms across treatments. Abdominal pain was associated with STT (ITT-RR: 1.75, 95% CI: 1.07-2.86).

CONCLUSION

STT was a safe regimen but with acceptable efficacy (most eradication rates <90%). Due to rising clarithromycin resistance, the study suggests avoiding STT as a first-line treatment. These results must be considered with caution due to the low representativeness of several Latin American countries and the lack of recent high-quality randomized studies.

Preparation and function of composite asymmetric chitosan/CM-chitosan membrane

A novel composite asymmetric chitosan/CM-chitosan membrane (C-P-C) was prepared, the top-layer was chitosan (CS), the intermediate was PVA, and the substrate was carboxymethyl chitosan (CM-CS). C-P-C membrane had capability in mechanical strength, light transparence, vapor permeability, and wound skin joining. The CS and CM-CS in C-P-C membrane were selected by series independent experiments, respectively. CS (MW 90,000 Da) had the highest antibacterial activity for E.coli. CM-CS had biocompatibility, no cytotoxicity, and had the activity of promoting growth of human skin fibroblast and inhibiting the growth of keloid fibroblast. The normal skin fibroblast can growth on the CM-CS surface of C-P-C, and have no conglomeration in higher cell density, and the keloid fibroblast could not growth on CM-CS surface of C-P-C. The animal experiment demonstrated that wound, covered with the C-P-C membrane, was hemostatic, healing quickly and had histocompatibility. The results indicated that the C-P-C membrane could be used as dressing of skin repair, and had the potential in promoting wound healing and inhibiting the keloid formation.

Simultaneous determination of amoxicillin and ranitidine in rat plasma by high-performance liquid chromatography

A high-performance liquid chromatography method using ultraviolet detection at 230 nm for the simultaneous determination of amoxicillin and ranitidine in rat plasma has been validated. Plasma samples after pretreatment with acetonitrile to effect deproteinization were dried under N2 and reconstituted with water. The standard calibration curves for amoxicillin and ranitidine were linear (r2=0.9999) over the concentration range of 0.2-20 microg ml-1 and 0.03-6 microg ml-1 in rat plasma, respectively. The intra- and inter-day assay variability range for amoxicillin was 2.4-8.5% and 3.2-11.7%, and for ranitidine was 1.7-9.0% and 4.5-10.1%, respectively. This method has been successfully applied to a pharmacokinetic study after oral coadministration of amoxicillin and ranitidine to rats.

Pathogenesis and therapy of gastric and duodenal ulcer disease

Despite the decreasing frequency of Helicobacter pylori-induced peptic ulcers, peptic ulcer disease remains a major clinical problem partly because nonsteroidal anti-inflammatory drug ulcers have increased in frequency. The reduction in nonsteroidal anti-inflammatory drug ulcers by use of selective cyclooxygenase-2 inhibitors will not eliminate the problem because of increased use of aspirin for cardiovascular prophylaxis. This article reviews current concepts of peptic ulcer pathogenesis and therapy according to ulcer etiology; discusses potential interactions between etiologies; and considers the therapy for H pylori infection including the effects of antimicrobial resistance, and the role of bismuth quadruple therapy or furazolidone salvage therapy.

Helicobacter pylori

H. pylori infection is now recognized as causing serious and life threatening disease in 20% to 30% of those infected. Reliable therapy is problematic. This article addresses the current approach to diagnosis and therapy and new considerations regarding whom to treat. The emphasis of the association of the gastric cancer phenotype of H. pylori infection (cagA positive H. pylori corpus gastritis) and protection against gastroesophageal reflux disease is an example of epidemiology without regard to the biology. Improvements in health and diet and an increase in body mass have accompanied the natural loss of H. pylori from the population. The search for virulence factors to help direct therapy to those who would most benefit has, to date, proved fruitless. Whenever H. pylori is diagnosed, it should be treated.

Chemical speciation applied to bio-inorganic chemistry

The processes of converting new chemistry into new healthcare, environment-friendly, products are considerably facilitated when chemical speciation data are available. These identify causal links between speciation and biological responses based upon specific chemical species rather than total concentrations. The effective roles of bismuth for ulcer treatment, of Ca, Zn, Sn and F in dentifrices, and of zinc species and common cold symptoms are described. A new readily biodegradable ligand for minimising the environmental impact of washing powders, Al and Alzheimer's disease (and the absence of a causal link), and an audit of Cu and Zn flow from wound dressing through wound fluid to healing tissue, are all discussed in detail.

Practical advice on eradicating Helicobacter pylori infection

Peptic ulcer disease associated with H pylori infection is curable. The important factors in selecting therapy are efficacy of eradication, prevention of resistance, avoidance or minimization of adverse effects, patient compliance, and cost. The most effective regimens include a bismuth preparation or antisecretory drug (proton pump inhibitor or H2 receptor antagonist) plus two antibiotics administered for 14 days. Dual-drug therapies are not recommended. Triple-drug regimens are more likely to eradicate H pylori and less likely to generate resistant strains among surviving organisms. In general, cure of the infection should be confirmed 4 weeks after completion of the treatment. Antibiotic resistance is an important consideration in choosing therapy, and patients should be taught the importance of compliance. When treatment fails, antibiotic combinations should not be repeated. Considerations for anti-H pylori treatment in a managed care environment mirror those for good medical practice in general, with special attention to stringent cost-control or outcomes-driven measures.