Helicobacter pylori infection in Korea

Overview of Helicobacter pylori Infection in Indonesia: What Distinguishes It from Countries with High Gastric Cancer Incidence?

Helicobacterpylori infects more than half the human population. However, the prevalence in Indonesia is low, as is the prevalence of gastric cancer. Hence, it could be instructive to compare these prevalence rates and their determining factors with those of countries that have high gastric cancer incidence. Ethnicity and genetic characteristics of H. pylori are important determinants of the H. pylori infection rate in Indonesia. The infection rate is higher in Bataknese, Papuans and Buginese than in Javanese, the predominant ethnic group. Ethnicity is also an important determinant of the genetic characteristics of H. pylori. Analysis of CagA in the EPIYA segment showed that the predominant genotypes in Papuans, Bataknese and Buginese are ABB-, ABD- and ABC-type CagA, respectively. Meanwhile, in the countries with high gastric cancer incidence, almost all strains had East Asian type CagA. An antibiotic susceptibility evaluation showed that the standard triple therapy can still be used with caution in several cities. There is a very high rate of resistance to second-line regimens such as levofloxacin and metronidazole. Recent studies have shown that furazolidone, rifabutin and sitafloxacin are potential alternative treatments for antibiotic-resistant H. pylori infection in Indonesia. Rather than focusing on early detection and eradication as in countries with high gastric cancer prevalence, countries with low gastric cancer prevalence should focus on screening the several groups that have a high risk of gastric cancer. (Gut Liver 2021;15:-665)

Degranulated Eosinophils Contain More Fine Nerve Fibers in the Duodenal Mucosa of Patients With Functional Dyspepsia

Background/Aims

Functional dyspepsia (FD) is characterized as chronic recurrent upper gastrointestinal symptoms in the absence of any organic disorder. We hypothesized that duodenal low-grade inflammation activates superficial afferent nerve sprouting, thereby contributing to hypersensitivity in patients with FD.

Methods

A prospective case-control study was conducted in a tertiary referral center. FD was defined using the Rome III criteria. Standardized endoscopic biopsies were performed in the stomach and duodenum. Hematoxylin and eosin staining and immunohistochemical staining for major basic proteins were performed to detect granulated eosinophil-derived granules, and S-100 staining was performed to detect fine nerve fibers.

Results

A total of 51 patients with FD (82% female; mean age 35.8 ± 13.4 years) and 35 controls were enrolled. Activated eosinophil counts in the duodenum were significantly higher in patients with FD than in controls (41.4% vs 17.1%, P = 0.005). Microscopic duodenitis was more frequently detected in patients with FD than in controls. Fine nerve fibers were more abundant in patients with FD than in controls (45.1% vs 11.4%, P = 0.029). The abundance of fine nerve fibers highly correlated with the degree of activated eosinophils.

Conclusion

Duodenal low-grade inflammation, such as mucosal eosinophilic accumulation with degranulation, promoted mucosal enteric nerve fiber density and sprouting in patients with FD.

Helicobacter pylori: bacterial strategy for incipient stage and persistent colonization in human gastric niches

Helicobacter pylori (H. pylori) undergoes decades long colonization of the gastric mucosa of half the population in the world to produce acute and chronic gastritis at the beginning of infection, progressing to more severe disorders, including peptic ulcer disease and gastric cancer. Prolonged carriage of H. pylori is the most crucial factor for the pathogenesis of gastric maladies. Bacterial persistence in the gastric mucosa depends on bacterial factors as well as host factors. Herein, the host and bacterial components responsible for the incipient stages of H. pylori infection are reviewed and discussed. Bacterial adhesion and adaptation is presented to explain the persistence of H. pylori colonization in the gastric mucosa, in which bacterial evasion of host defense systems and genomic diversity are included.

Current status of functional dyspepsia in Korea

Dyspepsia refers to group of commonly occurring upper gastrointestinal symptoms. The majority of patients with dyspepsia suffer from functional (nonulcer) dyspepsia. Although there is a lack of epidemiological data from population-based or patient cohort studies in Korea, the current understanding of this condition has been updated using data from various recent research studies, which have facilitated the development of clinical guidelines for functional dyspepsia. According to a survey using the Rome III criteria, more than 40% of respondents who visited primary clinics and tertiary hospitals were defined as having functional dyspepsia, most of who were within a subgroup of patients with postprandial distress syndrome. In addition, a population-based cross-sectional survey revealed considerable overlap between functional dyspepsia and other functional gastrointestinal disorders, including gastroesophageal reflux disease (especially nonerosive reflux disease) and irritable bowel syndrome. In contrast to the results of Western trials, there is insufficient evidence to recommend a Helicobacter pylori test-and-treat strategy as an initial management approach to functional dyspepsia in Korea, suggesting the need for early endoscopic evaluation. Additional studies are necessary to adjust the cutoff age for implementation of immediate endoscopic evaluation of patients without alarm symptoms. Considering the prevalence of H. pylori infection and the limited efficacy of symptomatic relief after its eradication, further well-qualified studies in Korea are warranted.

[Guidelines for the treatment of functional dyspepsia]

Functional dyspepsia (FD) is defined as the presence of symptoms thought to originate in the gastroduodenal area, in the absence of any organic, systemic, or metabolic disease that is likely to explain the symptoms. Based on the available evidence and consensus opinion, thirteen consensus statements for the treatment of FD were developed using the modified Delphi approach. Proton pump inhibitor, prokinetics, and histamine 2 receptor antagonists are effective for the treatment of FD. Mucosal protecting agents, fundus relaxant, and drugs for visceral hypersensitivity can improve symptoms in FD. Antacids and antidepressants may help improving symptoms in FD. Comparing endoscopy with 'test and treat' of Helicobacter pylori, endoscopy may be more effective initial strategy for managing patients with FD in Korea given high incidence of gastric cancer and low cost of endoscopy. Helicobacter pylori eradication can be one of the therapeutic options for patients with FD. Psychotherapy is effective for those who have severe symptoms and refractoriness. Further studies are strongly needed to develop better treatment strategies for Korean patients with FD.

Efficacy of Helicobacter pylori eradication therapy in chronic liver disease

BACKGROUND/AIMS

Peptic ulcers occur more commonly in patients with liver cirrhosis (LC). Helicobacter pylori is recognized as the most important etiology in the pathogenesis of peptic ulcers. We investigated the efficacy of proton pump inhibitor (PPI)-based triple therapy in patients with chronic liver disease and peptic ulcer.

PATIENTS AND METHODS

One hundred sixty-three patients with LC or chronic hepatitis (CH) with a peptic ulcer and proven H. pylori infection were included. The combination of PPI, amoxicillin (1.0 g), and clarithromycin (500 mg), each given twice daily, was administered for 1 or 2 weeks. The eradication of H. pylori was determined by the rapid urease test, histology, or the 13C-urea breath test at least 4 weeks after completing the treatment.

RESULTS

The eradication rate of H. pylori was similar between the LC and CH groups; 82.6% and 88.1%, respectively. In addition, there were no significant differences in eradication rates between the patients with Child-Pugh class A and Child-Pugh class B/C disease. The side effects in each group were generally mild. Only the serum ALT levels showed a significant correlation with the success of H. pylori eradication in both the LC and CH groups.

CONCLUSION

The PPI-based triple therapy achieves high eradication rates for H. pylori infection, in patients with chronic liver disease, without significant side effects.

Prognosis for patients in a Korean population with ocular adnexal lymphoproliferative lesions

PURPOSE

To analyze the clinical features, treatment outcomes, and prognostic factors associated with lymphoproliferative lesions of the ocular adnexa in a Korean population.

METHODS

Data from 69 patients treated for adnexal lymphoproliferative disease in the 12-year period from 1991 to 2002 were retrospectively evaluated.

RESULTS

The 69 patients had a median age of 46 years (range, 15-73 years); 60 of these patients were diagnosed with extranodal marginal zone B cell lymphomas (MALT lymphomas) and had 10 year cause specific survival and relapse free survival rates of 95.6% and 82.6%, respectively. Of 6 patients (8.7%) with concurrent systemic lymphoma, including 4 diagnosed with stage IV disease, 3 died from lymphoma. Only one patient with a primary ocular adnexal MALT lymphoma developed systemic lymphoma, which was treated with surgical resection. Local recurrence either at the primary site or in the fellow eye occurred in 11.6% of patients at a median follow-up time of 102 months (range, 79-132 months), and was controlled using repeat irradiation in all cases. Statistical analysis showed the presence of concurrent systemic lymphoma, bilateral disease, and an advanced stage at diagnosis, were linked to lymphoma-related death (Log-rank test, p < 0.05) and systemic progression (Fisher's exact test, p < 0.05), and that the tumor location was not a prognostic factor for lymphoma-related death or relapse at any site.

CONCLUSIONS

Ocular adnexal lymphoproliferative disease in Koreans occurred at a relatively young age, and was mostly orbitally located and of the MALT subtype, which is highly localized and rarely associated with extraorbital relapse. Primary or secondary status, stage at presentation, and bilaterality were found to be prognostic factors.

Epidemiology and diagnosis of Helicobacter pylori infection

There have been no major breakthroughs in the field of epidemiology and diagnosis of Helicobacter pylori infection over the last year, thus for this reason, these two topics will be treated in the same chapter. Information on the incidence of infection, as in the study of Malaty et al. are now being published from long-term cohort follow-ups. The route of transmission of H. pylori remains controversial, with circumstantial evidence for infection via exposure to animals, contaminated water supplies and oral reservoirs being reported. The value of citric acid to improve urea breath test (UBT) results has been documented. A novel stool test has been released on the market and we are awaiting more information, while detection of antibodies in urine gave satisfactory results. However, the most interesting data comes from the study of McColl et al. who clearly proved on a large sample and a 1-year follow-up that the 'test and treat' strategy using UBT, as proposed in the Maastricht Consensus Report, is definitely the method to use.

East Asian genotypes of Helicobacter pylori strains in Amerindians provide evidence for its ancient human carriage

Phylogenies of indigenous microbes have been used as surrogates for the origins of the hosts that carry them. Conversely, polymorphisms may be used to date the spread of a microbial species when information about their host populations is available. Therefore, we examined polymorphisms in Helicobacter pylori, which persistently colonize the human stomach, to test the hypothesis that they have been ancient inhabitants of humans. Three H. pylori loci that previously have been shown to have phylogeographic affinity have been analyzed for two populations with different ethnic origins from Venezuela. In a group of Amerindian subjects from Amazonia, East Asian H. pylori genotypes were present for each of the loci examined but were absent in a mestizo population from Caracas. These findings provide evidence that H. pylori has been present in humans at least since ancestors of Amerindians migrated from Asia more than 11,000 years ago.