Current development of <i>Helicobacter pylori</i> eradication protocols

Abstract

H. pylori is one of the most common commensal microorganisms in the human body, colonizing up to 60% of the inhabitants of all continents. Some strains of H. pylori have acquired virulent properties and their presence can significantly complicate the course of atrophic gastritis of type B, gastric ulcer and duodenal ulcer, as well as malignant diseases of the stomach. In such situations, eradication therapy seems to be pathogenetically justified. International recommendations for standard first-line triple eradication therapy, including a proton pump inhibitor (PPI), amoxicillin and clarithromycin in a course of 7–10 days, were proposed in 1996. Until the beginning of the XXI century, it was actively and with high efficiency (up to 90%) used everywhere, but later reports began to appear about a catastrophic decrease in results (up to 60%). Then it turned out that the effectiveness of the three-component (triple) therapy directly correlates with the resistance to clarithromycin, which has increased significantly in recent decades, and so necessitated the creation of new H. pylori elimination schemes. The results of various schemes for H. pylori eradication were analyzed, including variants of modified triple therapy associated with the inclusion of new drugs or an increase in the duration of eradication. In particular, it was proposed to replace amoxicillin with metronidazole. However, further studies have shown that the combination of clarithromycin with amoxicillin seems to be preferable, which is due to the high level of H. pylori resistance to metronidazole in many countries. Attempts to use probiotics in parallel, in particular cultures of various Lactobacillus species, were analyzed, which increases the level of eradication during standard triple therapy from 61.5 to 81.6%, and also significantly reduces the severity of side effects. It has been shown that a promising way to increase the effectiveness of 7-day first-line therapy schemes with clarithromycin is the use of modern effective PPIs (for example, esomeprazole or rabeprazole). The scheme of modified sequential therapy with the replacement of clarithromycin with tetracycline or levofloxacin, which has shown high efficiency, is considered. A variant of standard triple therapy modified into quadrotherapy with the addition of metronidazole or tinidazole was analyzed. It has been shown that the sequential therapy scheme is ineffective for eradication of multidrug-resistant strains. Ideally, the treatment of bacterial infections should be based on endoscopic sampling of gastric mucosa biopsies, followed by microbiological determination of the sensitivity of the isolated isolates to antibacterial drugs in vitro.