The Korean Journal of Helicobacter and Upper Gastrointestinal Research最新文献

Owing to their superior pharmacokinetic and pharmacodynamic profiles, potassium-competitive acid blockers (P-CABs) score over proton pump inhibitors (PPIs) in the treatment of gastric acid-related disorders and may provide clinical benefit in the management of these conditions. Previous studies have compared P-CABs with PPIs for treatment of gastric acid-related disorders, and current data show that P-CABs are non-inferior to PPIs in the treatment of erosive esophagitis and as maintenance therapy. P-CABs are useful for effective healing and as maintenance medications in patients with severe esophagitis. These drugs also aid with healing of peptic ulcers and artificial ulcers secondary to gastric endoscopic submucosal dissection (ESD). Few studies have discussed prevention of delayed ulcer bleeding after gastric ESD and ulcers associated with long-term nonsteroidal anti-inflammatory drug administration. Well-controlled, large-scale prospective studies are warranted in future to compare P-CABs with PPIs.

The escalating prevalence of clarithromycin resistance in cases of Helicobacter pylori, insufficient acid suppression, and pharmacodynamic variations secondary to inter-individual differences in CYP2C19 polymorphism collectively contribute to suboptimal eradication rates observed with proton pump inhibitor (PPI)-based therapy. Compared with PPIs, potassium-competitive acid blockers (PCABs) produce rapid, potent, and long-lasting suppression of gastric acid through reversible inhibition of gastric H⁺, K⁺-ATPase. PCAB-based therapy results in significant inhibition of acid secretion and has therefore emerged as a novel and effective approach for H. pylori eradication. In this study, we review the efficacy and safety profile of PCAB-based eradication regimens comprising vonoprazan, tegoprazan, and fexuprazan.

Gastric acid-related disorders are commonly encountered in clinical practice. Acetylcholine, gastrin, and histamine are physiological agonists that stimulate acid secretion from parietal cells. Histamine plays a decisive role in the transformation of parietal cells into acid-secreting forms. The H⁺, K⁺- ATPase proton pump, which represents the final step of acid secretion, translocates from cytoplasmic tubulovesicles to secretory canaliculi upon parietal cell stimulation and facilitates exchange of intracellular H⁺ with extracellular K⁺ in a 1:1 ratio. Histamine-2 receptor antagonists and proton pump inhibitors (PPIs) are widely used in clinical practice, and potassium-competitive acid blockers (P-CABs) have gained attention in recent times. P-CABs address the unmet needs of patients who receive conventional PPIs and have broadened the spectrum of drug choices; however, further research is warranted to confirm long-term safety of these drugs. Comprehensive understanding of the mechanisms of actions, characteristics, advantages and disadvantages, and the adverse effect profile is essential for appropriate prescription of gastric acid-suppressive drugs. In this review, we provide a developing history and outline the pharmacological mechanisms underlying various gastric acid-suppressive drugs used in clinical settings.

Background/aims: Identification of Helicobacter pylori infection status is necessary as H. pylori is associated with gastric malignancy. Recently, a red linear scrape-like appearance on the gastric mucosa, called the "scratch sign," was reported to be associated with H. pylori-negative gastric mucosal status. Herein, we aimed to validate the association between the scratch sign and H. pylori infection status.

Methods: The data of patients who underwent screening endoscopy at Bundang Jesaeng General Hospital between March 2023 and April 2023 were reviewed. Patients were classified as having an H. pylori current infection or non-infection status based on the results of rapid urease tests. Patients who had undergone H. pylori eradication therapy were excluded. Endoscopic features of the gastric mucosa were assessed using the Kyoto classification of gastritis.

Results: The scratch sign appeared more frequently in patients with non-infection than in those with current infection status (32.7% vs. 10.6%, respectively; P<0.001). Multivariate analysis showed that only the presence of sticky mucus was significantly associated with the presence of the scratch sign. Patient without the scratch sign had a higher prevalence of open-type atrophy, intestinal metaplasia, enlarged folds, and diffuse redness, which reflected a higher Kyoto score.

Conclusions: Presence of the gastric mucosal scratch sign, a novel endoscopic marker, is indicative of H. pylori-negative status and appears to be inversely correlated with the presence of sticky mucus. In addition to the Kyoto classification of gastritis, detection of the scratch sign may facilitate identification of the H. pylori infection status.

Recent advances in endoscopic technology, including high-definition and image-enhanced endoscopy such as narrow-band imaging have facilitated close observation and detailed imaging of the gastric mucosa. Currently, endoscopy is performed in Korea primarily for evaluation of premalignant conditions and gastric cancer detection. Recent research has established the Kyoto classification of gastritis, a novel grading system for endoscopic gastritis, which enables prediction of Helicobacter pylori (H. pylori) infection. The Kyoto classification score is calculated based on the sum of scores for five main items (of 19 endoscopic findings indicative of H. pylori infection) such as atrophy, intestinal metaplasia, enlarged gastric folds, nodularity, and diffuse redness with/without regular arrangement of collecting venules (RAC). Of these five endoscopic findings, atrophy, intestinal metaplasia, enlarged gastric folds, and nodularity are associated with an increased risk and RAC with a decreased risk of gastric cancer. Previous studies have reported that a Kyoto classification score ≥2 indicates current or past H. pylori infection. An increase in the Kyoto classification score is associated with a high risk of gastric cancer; specifically, a Kyoto classification score ≥4 indicates a high risk of gastric cancer. However, H. pylori eradication is followed by disappearance of enlarged gastric folds, nodularity, and diffuse redness; therefore, this grading system cannot accurately reflect the gastric cancer risk in patients with previous H. pylori infection. Limited studies have discussed the Kyoto classification of gastritis in Korea. Therefore, further large-scale multicenter studies are warranted for validation of the Kyoto classification to predict H. pylori infection and gastric cancer risk.