1.
Review: Helicobacter pylori infection in children.
Seo, JH, Bortolin, K, Jones, NL
Helicobacter. 2020;:e12742
Abstract
Helicobacter pylori infection in children and adolescents differs in comparison to adults with respect to epidemiology, host responses, and disease manifestations. Furthermore, treatment options are limited in this population and antibiotic resistance rates continue to increase. Therefore, ongoing research is vital to understand disease pathogenesis and provide optimal management of children with infection. This review summarizes relevant publications from April 2019 to March 2020. Similar to adults, recent studies show a decreasing prevalence of infection in the pediatric population. Studies of pathogenesis investigated serum immune responses and the potential inverse association of infection and allergy. Several studies investigated the effect of H pylori and related inflammation on the gut microbiome. The recommendation of endoscopy-based testing to identify the cause of symptoms and not just H pylori, reserving noninvasive UBT or stool antigen tests for post-eradication follow-up, was supported by the current literature.
2.
Biological properties and pathogenicity factors of Helicobacter pylori.
Isaeva, GS, Fagoonee, S
Minerva gastroenterologica e dietologica. 2018;(3):255-266
Abstract
The unexpected discovery of Helicobacter pylori (H. pylori) has revolutionised the history of microbiology as well as of gastroenterology in the last 30 years, with an invaluable benefit for millions of persons worldwide. The confirmation that this Gram-negative spiral bacterium could live in the stomach has rendered out-of-date the concept of inhospitality of micro-organisms in the gastric environment, after a long history of unheard reports on the presence of spiral bacteria in the stomach. The pathogenicity of H. pylori depends on its ability to colonize as well as the capability to survive in the harsh gastric environment. This is possible by a coevolution between the pathogen itself and the host. Any perturbation of this equilibrium disrupts the host-pathogen interaction, promoting the pathological effects. H. pylori has a wide range of pathogenicity factors, in particular cytotoxins, enzymes of aggression, and factors providing protection against human defense systems. The most well-characterized cytotoxins contributing to epithelial cell damage are the vacuolating cytotoxin A (VacA) and the cytotoxin-associated gene A (CagA). Only detailed knowledge of the microbiology and genomics of H. pylori infection will allow a vaccine to be produced. Today, we know that H. pylori induces strong humoral and cellular immune responses, but these are incapable of eliminating the bacterium, raising doubts about the possibility of developing an effective vaccine easily. This review highlights microbiological findings concerning H. pylori infection, focusing on colonization, survival and pathogenicity.