Since the introduction of vonoprazan, a potassium-competitive acid blocker (P-CAB), it has been demonstrated to reversibly inhibit gastric acid secretion by engaging in potassium-competitive ionic binding to H+/K+-ATPase. In contrast, proton pump inhibitors (PPIs) achieve H+/K+-ATPase inhibition through covalent binding to cysteine residues of the proton pump. Reported cases have indicated an emerging trend of P-CAB-related gastropathies, similar to those associated with PPIs, as well as unique gastropathies specific to P-CAB use, such as the identification of web-like mucus. Pathologically, parietal cell profusions, which show a positively correlated with hypergastrinemia, have a higher incidence in P-CAB users compared to PPI users. Thus, this review aims to summarize the endoscopic and pathological findings reported to date concerning P-CAB-related gastric mucosal lesions. Additionally, it seeks to discuss the differences between the PPIs and P-CABs in terms of the formation and frequency of associated gastropathies. This review highlights the evident differences in the mechanism of action and potency of acid inhibition between P-CABs and PPIs, notably contributing to differences in the formation and frequency of associated gastropathies. It emphasizes the necessity to distinguish between P-CAB-related and PPI-related gastropathies in the clinical setting.

A 72-year-old man with jaundice by ampullary adenocarcinoma was treated at our hospital. For biliary decompression, a transpapillary, fully covered, self-expandable metal stent (FCSEMS) was deployed. Four days later, the patient developed acute cholangitis. Endoscopic carbon dioxide cholangiography revealed kinking of the common bile duct above the proximal end of the FCSEMS. A 7-F double-pigtail plastic stent was therefore placed through the FCSEMS to correct the kink, straightening the common bile duct (CBD) and improving cholangitis. This is the first report of a unique use of a double-pigtail plastic stent to correct CBD kinking. The placement of a double-pigtail plastic stent can correct CBD kinking, without requiring replacement or addition of a FCSEMS, and can lead to cost savings.
Aged ; Common Bile Duct/*injuries ; Constriction, Pathologic/surgery ; Decompression, Surgical/instrumentation/methods ; Humans ; Male ; Self Expandable Metallic Stents/adverse effects ; *Stents ; Torsion Abnormality/*surgery

A 69-year-old woman with jaundice was referred to our hospital. After a final diagnosis of pancreatic cancer with liver metastasis, we performed transpapillary biliary drainage with a covered self-expandable metal stent (SEMS). Three months later, we also placed an uncovered duodenal stent for duodenal stricture in a side-to-end fashion. Another month later, for biliary SEMS obstruction, we attempted a transpapillary approach. A duodenoscope was advanced and a guidewire was passed through the mesh of the duodenal stent into the bile duct with a flexible tip catheter, but the catheter was not. Thus, we exchanged the duodenoscope for a forward-viewing two-channel endoscope and used the left working channel with a flexible tip catheter. By adjusting the axis, we finally succeeded biliary cannulation and accomplished balloon cleaning for recanalization of the SEMS. This is the first case with successful biliary cannulation by combined use of a two-channel endoscope and a flexible tip catheter.
Aged ; Bile Ducts ; Catheterization ; Catheters ; Cholestasis ; Constriction, Pathologic ; Diagnosis ; Drainage ; Duodenoscopes ; Endoscopes ; Female ; Humans ; Jaundice ; Liver ; Neoplasm Metastasis ; Pancreatic Neoplasms ; Stents

BACKGROUND/AIMS: Although the risk of bleeding after endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is low, the safety of EUS-FNA in patients prescribed antithrom-botic agents is unclear. Therefore, this study evaluated the incidence of bleeding after EUS-FNA in those patients. METHODS: Between September 2012 and September 2015, patients who were prescribed antithrombotic agents underwent EUS-FNA at 13 institutions in Japan were prospectively enrolled in the study. The antithrombotic agents were managed according to the guidelines of the Japanese Gastrointestinal Endoscopy Society. The rate of bleeding events, thromboembolic events and other complications within 2 weeks after EUS-FNA were analyzed. RESULTS: Of the 2,629 patients who underwent EUS-FNA during the study period, 85 (62 males; median age, 74 years) patients were included in this stduy. Two patients (2.4%; 95% confidence interval [CI], 0.6% to 8.3%) experienced bleeding events. One patient required surgical intervention for hemothorax 5 hours after EUS-FNA, and the other experienced melena 8 days after EUS-FNA and required red blood cell transfusions. No thromboembolic events occurred (0%; 95% CI, 0.0% to 4.4%). Three patients (3.5%; 95% CI, 1.2% to 10.0%) experienced peri-puncture abscess formation. CONCLUSIONS: The rate of bleeding after EUS-FNA in patients prescribed antithrombotic agents might be considerable.
Abscess ; Asian Continental Ancestry Group ; Endoscopic Ultrasound-Guided Fine Needle Aspiration* ; Endoscopy, Gastrointestinal ; Erythrocyte Transfusion ; Fibrinolytic Agents* ; Hemorrhage* ; Hemothorax ; Humans ; Incidence ; Japan ; Male ; Melena ; Prospective Studies*