Associations among Gastric Juice pH, Atrophic Gastritis, Intestinal Metaplasia and Helicobacter pylori Infection

BACKGROUND/AIMS: Gastric juice plays a crucial role in the physiology of the stomach. The aim of this study is to evaluate associations among the pH of gastric juice, atrophic gastritis (AG), intestinal metaplasia (IM), pepsinogen, and Helicobacter pylori infection. METHODS: Gastric biopsies and juice were collected from 46 subjects who underwent endoscopies at Seoul National University Bundang Hospital between November 2011 and March 2013. H. pylori, AG and IM were evaluated, and pepsinogen I or II, I/II ratio, and interleukin (IL)-1β levels were measured. RESULTS: The mean pH of gastric juice was higher in the H. pylori-positive group (n=17) than that in the H. pylori-negative group (n=29) (4.54 vs 2.46, p=0.002). When patients were divided into pH < 3 (n=28) and pH ≥3 (n=18) groups, H. pylori was lower in the pH < 3 group (21.4%) than in the pH ≥3 group (61.1%) (p=0.007). The pH ≥3 group demonstrated AG and IM more frequently than the pH < 3 group in the body (p=0.047 and p=0.051, respectively) but not in the antrum. There were no differences in pepsinogen I or II, I/II ratio, and IL-1β levels between the two groups. CONCLUSIONS: There is a relationship between chronic H. pylori infection and gastric juice pH ≥3, which may originate from AG and IM in the body.

Rifabutin-based Fourth and Fifth-line Rescue Therapy in Patients with for Helicobacter pylori Eradication Failure / 대한소화기학회지

BACKGROUND/AIMS: Optimized regimen has not yet been established for failures of multiple Helicobacter pylori (H. pylori) eradication. Hence, we aimed to evaluate the efficacy of rifabutin-based rescue therapy, at least after three eradication failures. METHODS: Twelve patients, who failed in the treatment for H. pylori eradication at least three times, were consecutively enrolled between 2007 and 2015 at Seoul National University Bundang Hospital. The rifabutin-based rescue regimen was consisted of proton pump inhibitor (PPI), rifabutin (150 mg b.i.d.), and amoxicillin (1 g b.i.d.), given for 7 or 14 days. MIC concentration test by the agar dilution method was performed on six patients prior to rifabutin-based rescue therapy. RESULTS: One patient did not take this regimen, and per-protocol (PP) analysis was performed in 11 patients. The overall eradication rate by intention-to-treat and PP analysis with rifabutin-based rescue therapy was 50.0% (6/12 patients) and 54.5% (6/11 patients), respectively. There was no difference of the eradication rate depending on the underlying disease, smoking, alcohol, number of previous eradication failures, and CYP2C19 genotype. All of the six patients were susceptible to rifabutin, but only three of them succeeded in eradicating with H. pylori. Side effects occurred in two patients (18.2%), and compliance was 90.9%. CONCLUSIONS: Even the eradication rate of rifabutin-based rescue therapy was not very good. Rifabutin-based rescue therapy could be considered as a rescue therapy, perhaps as the fourth or the fifth-line treatment option. No correlation of rifabutin sensitivity with eradication success rate of H. pylori suggests that frequent administration of high dose PPI and amoxicillin might be important.

Effects of Age on Esophageal Motility: Use of High-resolution Esophageal Impedance Manometry

BACKGROUND/AIMS: Disturbances of esophageal motility have been reported to be more frequent the aged population. However, the physiology of disturbances in esophageal motility during aging is unclear. The aim of this study was to evaluate the effects of age on esophageal motility using high-resolution esophageal impedance manometry (HRIM). METHODS: Esophageal motor function of 268 subjects were measured using HRIM in 3 age groups, 65 years (Group C, n = 62). Lower esophageal sphincter (LES) and upper esophageal sphincter (UES) pressures, integrated relaxation pressure, distal contractile integral, contractile front velocity, distal latency, and pressures and duration of contraction on 4 positions along the esophagus, and complete bolus transit were measured. RESULTS: Basal UES pressure was lower in Group C (P < 0.001) but there was no significant difference in the LES pressure among groups. Contractile duration on position 3 (10 cm from proximal LES high pressure zone) was longer in Group C (P = 0.001), and the contractile amplitude on position 4 (5 cm from proximal LES high pressure zone) was lower in Group C (P = 0.005). Distal contractile integral was lower in Group C (P = 0.037). Contractile front velocity (P = 0.015) and the onset velocity (P = 0.040) was lower in Group C. There was no significant difference in impedance values. CONCLUSIONS: The decrease of UES pressure, distal esophageal motility, and peristaltic velocity might be related with esophageal symptoms in the aged population.

Comparison of Gastric Microbiota Between Gastric Juice and Mucosa by Next Generation Sequencing Method

BACKGROUND: Not much is known about the role of gastric microbiota except for Helicobacter pylori in human health and disease. In this study, we aimed to detect human gastric microbiota in both gastric mucosa and gastric juice by barcoded 454-pyrosequencing of the 16S rRNA gene and to compare the results from mucosa and juice. METHODS: Gastric biopsies and stomach juices were collected from 4 subjects who underwent standard endoscopy at Seoul National University Bundang Hospital. Gastric microbiota of antral mucosa, corpus mucosa samples, and gastric fluids were analyzed by barcoded 454-pyrosequencing of the 16S rRNA gene. The analysis focused on bacteria, such as H. pylori and nitrosating or nitrate-reducing bacteria. RESULTS: Gastric fluid samples showed higher diversity compared to that of gastric mucosa samples. The mean of operational taxonomic units was higher in gastric fluid than in gastric mucosa. The samples of gastric fluid and gastric mucosa showed different composition of phyla. The composition of H. pylori and Proteobacteria was higher in mucosa samples compared to gastric fluid samples (H. pylori, 66.5% vs. 3.3%, P = 0.033; Proteobacteria, 75.4% vs. 26.3%, P = 0.041), while Actinobacteria, Bacteroidetes, and Firmicutes were proportioned relatively less in mucosa samples than gastric fluid. However there was no significant difference. (Actinobacteria, 3.5% vs. 20.2%, P = 0.312; Bacteroidetes, 6.0% vs. 14.8%, P = 0.329; Firmicutes, 12.8% vs. 33.4%, P = 0.246). CONCLUSIONS: Even though these samples were small, gastric mucosa could be more effective than gastric fluid in the detection of meaningful gastric microbiota by pyrosequencing.

The Effect of Sex on the Azoxymethane/Dextran Sulfate Sodium-treated Mice Model of Colon Cancer

BACKGROUND: The colitis-associated cancer exhibits different characteristics according to sex in the initiation and progression of the tumors. The aim of this study was to investigate the sex-associated difference in the azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis-associated cancer model. METHODS: The AOM/DSS ICR mouse model was established to compare male with female, and then the severity of colitis-associated carcinogenesis was examined macroscopically and histologically regarding the number, size, and location of tumors. Subsequently, levels of colonic mucosal cytokine, interleukin (IL)-1β and myeloperoxidase (MPO) were assessed. RESULTS: At the 16th week, the tumor multiplicity and the pro-inflammatory factors differed according to sex. The total tumor number was significantly higher in male (P = 0.020) and the number of large tumors (diameter > 2 mm) was higher in male (P = 0.026). In male, the tumors located more in distal colon (P = 0.001). MPO was significantly higher in AOM/DSS-treated male mice compared to the control group (P = 0.003), whereas the corresponding female group showed no significant change (P = 0.086). Colonic IL-1β level significantly increased in AOM/DSS groups compared to control groups both in male and female (male, P = 0.014; female, P = 0.005). It was higher in male group; however, there was no statistical significance (P = 0.226). CONCLUSIONS: In AOM/DSS murine model, colitis-associated colon tumorigenesis are induced more severely in male mice than female probably by way of inflammatory mediators such as IL-1β and MPO. The sex-related differences at the animal model of colon cancer suggest the importance of approach to disease with sex-specific medicine in human.