Masaharu Miki

Difference in localization of esophageal mucosal breaks among grades of esophagitis

Background:  Gastroesophageal reflux occurs mainly during the daytime in patients with Los Angeles grade A esophagitis, but predominantly during the night in patients with grade C and D esophagitis. The purpose of the present paper was to investigate whether this difference in the pattern of gastroesophageal reflux influences the circumferential localization of erosions in the esophageal wall.

Effects of mosapride on esophageal functions and gastroesophageal reflux

Background and Aim:  A substantial number of patients with gastroesophageal reflux disease show symptomatic resistance to high‐dose proton pump inhibitors. In those cases, prokinetics are possible candidates for treatment. The aim of the present study was to determine whether mosapride, a prokinetic agent, stimulates esophageal functions, and prevents acidic and non‐acidic gastroesophageal reflux.

Tolerance to H2 receptor antagonist correlates well with the decline in efficacy against gastroesophageal reflux in patients with gastroesophageal reflux disease

Background and Aim:  The attenuated antisecretory activity of H2 receptor antagonists (H2RA) during continuous administration is known as the tolerance phenomenon. The authors recently clarified that presence or absence of Helicobacter pylori infection influences the occurrence of the tolerance phenomenon. The aim of this study was to clarify whether tolerance to H2RA is correlated with attenuation of the inhibitory effect against gastroesophageal acid reflux in patients with gastroesophageal reflux disease (GERD).

Half-solidification of nutrient does not decrease gastro-esophageal reflux events in patients fed via percutaneous endoscopic gastrostomy

BACKGROUND & AIMS Percutaneous endoscopic gastrostomy (PEG) tube feeding is widely used for patients with swallowing dysfunction, and aspiration pneumonitis induced by reflux of gastric contents is one of the most frequent and life-threatening events in such patients. We performed this study to clarify the effect of half-solidification of nutrient on gastro-esophageal reflux (GER) of acidic and non-acidic gastric contents in patients with PEG. METHODS The subjects were 14 elderly patients undergoing PEG feeding (female: 11, mean age 83.1 y). Twenty-four hour esophageal multichannel intraluminal impedance (MII) and pH (MII-pH) monitoring were performed during and after feeding with half-solid and liquid nutrient, respectively. The numbers of GER events during 4h after the start of feeding were compared. RESULTS There was no significant difference in the total number of GER events between half-solid nutrient feeding and liquid nutrient feeding (5.6+/-1.5 vs. 6.6+/-1.5). The number of acid reflux events after half-solid nutrient feeding tended to be higher than that after liquid nutrient feeding (1.9+/-1.1 vs. 1.4+/-0.8). CONCLUSION Half-solidification of nutrition does not appear to be effective for preventing GER caused by liquid PEG feeding.

Usefulness of catheterless radiotelemetry pH monitoring system to examine the relationship between duodenal acidity and upper gastrointestinal symptoms.

Background and Aim:  To clarify the usefulness of a newly designed method for measuring intraduodenal pH to examine the relationship between duodenal acidity and upper gastrointestinal symptoms during intragastric acid infusion.

A comparative study of intragastric acidity during post‐breakfast and pre‐dinner administration of low‐dose proton pump inhibitors: a randomized three‐way crossover study

The absorption and bioavailability of proton pump inhibitors is influenced by food intake. Proton pump inhibitors bind to the parietal cell active proton pump, which is maximally stimulated after dinner: usually the largest meal of the day. However, it has not been fully clarified whether the efficacy of proton pump inhibitors differs between post‐breakfast and pre‐dinner dosing.

Study of arteriosclerosis in patients with hiatal hernia and reflux esophagitis

Background and Aim:  It has been reported that the prevalence of hiatal hernia (HH) and reflux esophagitis (RE) increases with age, as does the degree of arteriosclerosis. However, it has not been investigated whether or not arteriosclerosis is correlated with the presence of HH and RE. Therefore, we prospectively investigated the degree of arteriosclerosis in patients with HH and RE compared with subjects without HH and RE.

Generation of Gastroesophageal Reflux Disease Symptoms During Esophageal Acid Infusion With Concomitant Esophageal pH Monitoring in Healthy Adults

Background/Aims The sensitivity of the upper and lower esophageal mucosa to acid is considered to differ. We investigated the relationship between pH changes in different sites of the esophagus and generation of gastroesophageal reflux symptoms during an acid infusion test. Methods An acid infusion catheter was placed at 5 or 15 cm above the lower esophageal sphincter (LES) in 18 healthy volunteers, while a 2-channel pH sensor catheter was also placed in each with the sensors set at 5 and 15 cm above the LES. Solutions containing water and hydrochloric acid at different concentrations were infused through the infusion catheter. Results Acid infusion in the upper esophagus caused a pH drop in both upper and lower esophageal sites, whereas that in the lower esophagus resulted in a significant pH drop only in the lower without a corresponding pH decline in the upper esophagus. Stronger heartburn, chest pain, and chest oppression symptoms were noted when acid was infused in the upper as compared to the lower esophagus, while increased intra-esophageal acidity strengthened each symptom. Regurgitations caused by upper and lower esophageal acid infusions were similar, and not worsened by a larger drop in intra-esophageal pH. Chest pain was caused only by lowered intra-esophageal pH, while heartburn, chest oppression, and regurgitation were induced by a less acidic solution. Conclusions Higher intra-esophageal acidity caused stronger heartburn, chest pain, and chest oppression symptoms. However, regurgitation was not significantly influenced by intra-esophageal acidity. The upper esophagus showed higher acid sensitivity than the lower esophagus.