الفهرس 
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Abstract
Helicobacter pylori, a member of Epsilon proteobacteria, is a Gram-negative microaerophilic bacterium that colonizes gastric mucosa of about 50% of the human population. Although most infections caused by H. pylori are asymptomatic, the microorganism is strongly associated with serious diseases of the upper gastrointestinal tract such as chronic gastritis, peptic ulcer, duodenal ulcer, and gastric cancer, and it is classified as a group I carcinogen. The prevalence of H. pylori infections varies worldwide. The H. pylori genotype, host gene polymorphisms, and environmental factors determine the type of induced disease. Currently, the most common therapy to treat H. pylori is the first line clarithromycin–based triple therapy or a quadruple therapy replacing clarithromycin with new antibiotics. Despite the enormous recent effort to introduce new therapeutic regimens to combat this pathogen, treatment for H. pylori still fails in more than 20% of patients, mainly due to the increased prevalence of antibiotic resistant strains. As one of the most prevalent infections globally, Helicobacter pylori (H. pylori) continues to present diagnostic and therapeutic challenges for clinicians worldwide. Diagnostically, the “test-and-treat” strategy is the recommended approach for healthcare practitioners when managing this potentially curable disease. The choice of testing method should be based on several factors including patient age, presenting symptoms, and medication use, as well as test reliability, availability, and cost. With rising antibiotic resistance, particularly of macrolides, care must be taken to ensure that therapy is selected based on regional resistance patterns and prior antibiotic exposure. In the USA, macrolide antibiotic resistance rates in some areas have reached or exceeded a generally accepted threshold, such that clarithromycin triple therapy may no longer be an appropriate first-line empiric treatment. Instead, bismuth quadruple therapy should be considered, while levofoxacin-based or alternative macrolide-containing therapies are also options. Once treated, it is essential to test for eradication as untreated H. pylori is associated with serious complications including peptic ulcer disease, mucosa-associated lymphoid tissue lymphoma, and gastric cancer.