Insights into the Pathogenesis, Virulence Factors, and Diagnosis of Helicobacter pylori: A Comprehensive Review

Аннотация

Article Information The H. pylori bacterium, which resides in the human stomach and is linked to a number of gastrointestinal illnesses, is introduced in-depth in this article. We examine how H. pylori Received: Jun 20, 2023 establishes infection, thwarts the hosting immune response, and causes inflammation as Accepted: August 11, 2023 we explore the pathophysiology of this bacterium. We also talked about how H. pylori influences host cells and develops a favorable environment for survival. We also go over the Published: September 06, 2023 many methods for identifying H. pylori, such as endoscopy, biopsy, blood, breath, feces, and others. We stress the importance of an accurate and speedy diagnosis while outlining the Keywords advantages and disadvantages of each diagnostic strategy to manage disorders caused by H. pylori effectively. Throughout this review, we aim to unravel the mysteries surrounding H. Helicobacter pylori, Endoscopy, pylori, providing valuable insights into its pathogenesis, the intricate interplay of virulence PCR, Urea Breath Test, factors, and the diverse diagnostic strategies employed in clinical practice. Enhancing our Serology Test understanding of H. pylori can pave the way for improved therapies and patient outcomes. INTRODUCTION development of H. pylori - Escherichia coli shuttlecock Firstly, Helicobacter pylori infection has become more vectors for cloning investigations (Pohl et al., 2019). While frequent in recent years, affecting around population the presence of H. pylori-infected bacterial virus has been (Keller et al., 2021; Tonkic et al., 2012). Accurate H. recognized, there remains a need for comprehensive pylori detection is essential for treating symptomatic characterization in this regard. In contrast to highly clonal people who are infected. Since Marshall and others’ bacterial diseases such as Mycobacterium tuberculosis, 1983 discovery of this spiral-shaped, gram-negative H. pylori exhibits genetic diversity, indicating a lack of bacteria, many diagnostic methods have been created clonality (Leszczyńska et al., 2010). Consequently, each (Kim & Wang, 2021). Some tests base their results on patient harboring H. pylori carries a distinct strain, although a variety of bacterial traits, such as their appearance minor variations may exist among relatives. The genetic (histology, culture), immunology (serology, stool test, variability observed in H. pylori may represent an adaptive immunohistochemistry), genetics (PCR), or enzymatic response to the gastrointestinal environment of its host activity (13C-urea breath test, quick urease test) (Mišak & and the unique patterns exhibited (Leszczyńska et al., Hojsak, 2021). Generally, these techniques may be divided 2010). Various mechanisms such as DNA rearrangement, between invasive testing (histology, urease test, culture), as well as the insertion and deletion of foreign sequences, which demands endoscopy of the upper gastrointestinal are considered to contribute to the genetic heterogeneity tract and stomach biopsies, and non-invasive tests observed in H. pylori (Ferwana et al., 2015). (serology, 13C-urea breath test, stool antigen test). Each test has advantages, weaknesses, and restrictions that vary Virulence factors of H. pylori depending on the clinical circumstances and the inquest PAI cag (Mišak & Hojsak, 2021). Although H. pylori infection always leads in recurrent gastritis, the majority of infected patients have absence Description of H. pylori further issues and show no evident clinical indicators of Genomic characteristics, plasmid presence, and infection (Mezmale et al., 2020). This raised the possibility strain diversity are all pertinent factors that warrant that certain strains are more virulent than others. Early consideration. The two sequenced genomes of Helicobacter studies of H. pylori strains’ varied pathogenic qualities pylori exhibit a size of more or less 1.9 Mbp and possess a revealed that increasing pathogenicity was associated into G+C composition ranging from 31% to 45% (4). Notably, capacity of their in addition aggressive strains to generate this bacteria strain 27595 encompasses 1,587 genes, while phenotypic alterations, hyalinization, and progressive strain J99 contains a slightly lower count of 1,491 genes degeneration of in vitro-cultured cells. This gene is (Zamani et al., 2018). It is deserve noting with various present in around 60 to 80% it (Malfertheiner et al., strains of this bacteria may harbor cryptic plasmids 2017). and is a signal for a genomic PAI of about 40 kb that lack discernible antibiotic resistance or virulence that estimate between 37 and 51 proteins (Bessède et al., genes. Interestingly, certain plasmids are utilized in the 2017), depending on the strain examined. CagA+ strains 1 Department of science, Basic Education collage, Wasit University, Wasit, Iraq 2 Department of Biology, College of Science, Mustansiriyah University, Baghdad, Iraq * Corresponding author’s e-mail