Helicobacter pylori (H. pylori) infection is a common bacterial infection for humans. Current knowledge implies that acquisition of H. pylori seems to occur predominantly in childhood and that a major role of intrafamilial spread is not controversial. However, the major route of transmission remains poorly understood. According to the nation-wide seroprevalence study for 5,732 asymptomatic Korean population in 1998, the seroprevalence of H. pylori infection was 46.6%, showing the transition from a developing country to a developed country. The seroprevalence in children (neonate-15 yr) and adult (16-79 yrs) were 17.2% and 66.9%, respectively. According to multivariate analysis, variables such as sex, age, geographic area, crowding (number of person per room) in childhood, economic status in childhood, and types of housing in childhood were significantly and independently associated with H. pylori seroprevalence of adults. In children, age, geographic area, household income, mother's education, and drinking water source were significant factors of H. pylori infection. The seroprevalence survey in 2005 showed that it decreased to 59.6% from 66.9% in the adult (16-79 yrs) over the period of 7 years, especially, in young subjects less than 50 years, Seoul and Gyeonggi suggesting that this decrease may be due to the improvement of socioeconomic status and hygiene.
Adult ; Bacterial Infections ; Child ; Crowding ; Developed Countries ; Developing Countries ; Drinking Water ; Education ; Family Characteristics ; Gyeonggi-do ; Helicobacter pylori ; Housing ; Humans ; Hygiene ; Multivariate Analysis ; Prevalence* ; Seoul ; Seroepidemiologic Studies ; Social Class

Gastric cancer, the most common cancer in Korea, has come to be more frequently detected in the early stage thanks to regular endoscopy regardless of gastrointestinal symptoms. Early gastric cancer can be treated by endoscopic submucosal dissection or laparoscopic surgery, and its prognosis is very excellent. Thus, it is of an utmost importance to develop efficient screening method and set appropriate interval for the accurate diagnosis of early gastric cancer. Endoscopic screening for every two year is recommended, but the interval could be shortened in case of precancerous condition such as atrophic gastritis and intestinal metaplasia or subjects in a family with a history of gastric cancer. During the investigation, the benefit of using serology of H. pylori infection and serum pepsinogen I/II ratio of less than or equal to 3, instead of direct endoscopy, should also be considered for the selection of a high risk group of gastric cancer in Korea. Recently, appropriate screening and accurate diagnosis of early gastric cancer has become one of the most important issues.
Endoscopy ; Gastritis, Atrophic ; Humans ; Korea ; Laparoscopy ; Mass Screening ; Metaplasia ; Pepsinogen A ; Precancerous Conditions ; Prognosis ; Stomach Neoplasms

Gastric cancer is associated with high morbidity and mortality worldwide. To reduce the socioeconomic burden related to gastric cancer, it is very important to identify and manage high risk group for gastric cancer. In this review, we describe the general risk factors for gastric cancer and define high risk group for gastric cancer. We discuss strategies for the effective management of patients for the prevention and early detection of gastric cancer. Atrophic gastritis (AG) and intestinal metaplasia (IM) are the most significant risk factors for gastric cancer. Therefore, the accurate selection of individuals with AG and IM may be a key strategy for the prevention and/or early detection of gastric cancer. Although endoscopic evaluation using enhanced technologies such as narrow band imaging-magnification, the serum pepsinogen test, Helicobacter pylori serology, and trefoil factor 3 have been evaluated, a gold standard method to accurately select individuals with AG and IM has not emerged. In terms of managing patients at high risk of gastric cancer, it remains uncertain whether H. pylori eradication reverses and/or prevents the progression of AG and IM. Although endoscopic surveillance in high risk patients is expected to be beneficial, further prospective studies in large populations are needed to determine the optimal surveillance interval.
Gastroscopy ; Helicobacter Infections/complications/diagnosis ; Humans ; Risk Factors ; Socioeconomic Factors ; Stomach Neoplasms/*diagnosis/etiology/prevention & control/therapy

Serum pepsinogen (sPG) is a marker of gastric mucosal atrophy, a condition that has been associated with an increased risk of gastric neoplasia. A low sPGI level and a low PG I/II ratio have been associated with severe gastric atrophy, and are frequently found in gastric cancer. Because the prevalence of gastric cancer is high in Korea, it would be convenient if a good biomarker for gastric cancer were developed. Two studies recently investigated the efficacy of sPG along with Helicobacter pylori (H. pylori) as a screening tool for gastric cancer. In these studies, sPG was measured using a Latex enhanced Turbidimetric Immunoassay. We found that H. pylori IgG status, age and gender were associated with serum pepsinogen levels. Thus, to increase the ability of the PG I/II ratio to detect atrophic gastritis, the cutoff value for the PG I/II ratio should be stratified according to the H. pylori IgG status. In addition, a PG I/II ratio (< or =3.0), which has been widely used as an international standard for gastric cancer, was found to be a reliable marker for the detection of gastric dysplasia or gastric cancer, especially of the intestinal type. The efficacy of the test in Korea was lower than the efficacy in Japan. However, the detecting power of a PG I/II ratio (< or =3.0) was significantly increased in the presence of H. pylori. The ratio together with H. pylori psotivitiy could provide a means of identifying persons at high risk of developing gastric cancer in Korea.
Atrophy ; Gastrins ; Gastritis, Atrophic ; Helicobacter pylori ; Humans ; Immunoassay ; Immunoglobulin G ; Japan ; Korea ; Latex ; Mass Screening ; Pepsinogen A ; Prevalence ; Stomach Neoplasms

Proton pump inhibitor (PPI) is a prodrug which is activated by acid. Activated PPI binds covalently to the gastric H+, K+-ATPase via disulfide bond. Cys813 is the primary site responsible for the inhibition of acid pump enzyme, where PPIs bind. Omeprazole was the first PPI introduced in market, followed by pantoprazole, lansoprazole and rabeprazole. Though these PPIs share the core structures benzimidazole and pyridine, their pharmacokinetics and pharmacodynamics are a little different. Several factors must be considered in understanding the pharmacodynamics of PPIs, including: accumulation of PPI in the parietal cell, the proportion of the pump enzyme located at the canaliculus, de novo synthesis of new pump enzyme, metabolism of PPI, amounts of covalent binding of PPI in the parietal cell, and the stability of PPI binding. PPIs have about 1hour of elimination half-life. Area under the plasmic concentration curve and the intragastric pH profile are very good indicators for evaluating PPI efficacy. Though CYP2C19 and CYP3A4 polymorphism are major components of PPI metabolism, the pharmacokinetics and pharmacodynamics of racemic mixture of PPIs depend on the CYP2C19 genotype status. S-omeprazole is relatively insensitive to CYP2C19, so better control of the intragastric pH is achieved. Similarly, R-lansoprazole was developed in order to increase the drug activity. Delayed-release formulation resulted in a longer duration of effective concentration of R-lansoprazole in blood, in addition to metabolic advantage. Thus, dexlansoprazole showed best control of the intragastric pH among the present PPIs. Overall, PPIs made significant progress in the management of acid-related diseases and improved health-related quality of life.
2-Pyridinylmethylsulfinylbenzimidazoles ; Benzimidazoles ; Gastric Acid ; Genotype ; Half-Life ; Hydrogen-Ion Concentration ; Imidazoles ; Nitro Compounds ; Omeprazole ; Proton Pump Inhibitors ; Proton Pumps ; Protons ; Pyridines ; Quality of Life

Although there are many guidelines recommending Helicobacter pylori (H. pylori) eradication therapy for atrophic gastritis (AG) and intestinal metaplasia (IM), there have been contradictory reports regarding the reversibility of precancerous lesions such as AG and IM after eradication of H. pylori. There have been many reports that have shown AG seems to improve upon eradication of H. pylori to some extent. In contrast, IM has been regarded as ‘the point of no return’ according to previous reports. However, as recent studies have suggested the improvement of intestinal metaplasia as well, early eradication therapy for reversible histological status is important and necessary for the prevention of gastric cancer. In this review, we focused on the progress of gastritis resulting in AG and IM mainly by H. pylori, the relationship of AG and IM with gastric cancer, the subtype of IM, and the reversibility of AG and IM by eradication of H. pylori. Finally, we introduced the recent extension of indications for H. pylori eradication with coverage by medical insurance, which was published by the Korean Ministry of Health and Welfare in January 2018.
Gastritis ; Gastritis, Atrophic* ; Helicobacter pylori* ; Helicobacter* ; Insurance ; Metaplasia* ; Stomach Neoplasms

The distribution of gut microbiota varies according to age and sex. Gut microbiota are known to contribute to gastrointestinal (GI) diseases such as irritable bowel syndrome, inflammatory bowel disease, and colon cancer; however, the exact etiology remains elusive.Sex hormone such as estrogen and testosterone control the microbiota mainly due to different effect on the immunity. In addition, the diet depending on gender also affect the gut microbiota. Furthermore, the metabolism of estrogen and androgen was reported to be related to the gut microbiome. However, there have been few comprehensive review articles regarding the effect of microbiota on GI diseases. In this review, the factors which affect the gut microbiota and the interplay of microbiota and GI diseases in terms of sex- and gender differences were briefly summarized.

We aimed to evaluate associations between the ratio of serum estrone (E1) to estradiol (E2) and parameters related to serum glucose metabolism and insulin resistance in women with polycystic ovary syndrome (PCOS). Methods: In total, 133 women between the ages of 18 and 35 diagnosed with PCOS were enrolled in this study. All participants with PCOS underwent blood tests to determine hormonal and biochemical metabolic parameters and a standard 2-hour 75-g oral glucose tolerance test. They were divided into two groups according to the serum E1-to-E2 ratio: group 1 (E1/E2 ratio <2.0) and group 2 (E1/E2 ratio ≥2.0). Results: In the comparative analysis, the waist-to-hip ratio (WHR) was the only clinical variable that was significantly different between the two groups. Patients with a higher E1/E2 ratio showed higher fasting insulin levels, homeostasis model for insulin resistance, and postprandial glucose level at 2 hours (PPG2). In a correlation analysis, only PPG2 was significantly related to the serum E1/E2 ratio. However, after controlling for the confounding effects of body mass index (BMI) and WHR, fasting glucose was also significantly correlated with the serum E1/E2 ratio. Conclusion: Women with PCOS with a higher serum E1/E2 ratio were found to be more likely to show higher fasting insulin and postprandial glucose levels. Significant correlations were found between the serum E1/E2 ratio and both fasting and postprandial serum glucose levels after adjusting for BMI and WHR in women with PCOS.