矢野 智則

The safety of long-term proton pump inhibitor (PPI) and vonoprazan (VPZ) use is a relatively recent concern. Gastric mucosal redness was reported as a VPZ-associated lesion in a previous study. The aim of this study was to investigate the prevalence and risk factors for gastric mucosal redness. Between December 2020 and November 2021, 1,101 patients who underwent esophagogastroduodenoscopy were reviewed. The cohort was divided into four groups: Control (n=580), histamine-2 receptor antagonist (H2RA) (n=65), PPI (n=146) and VPZ groups (n=310). Gastric mucosal redness was present in 48/1,101 patients (4%). The prevalence in controls, H2RA, PPI and VPZ groups was 1.9% (11/580), 1.5% (1/65), 6.2% (9/146) and 8.7% (27/310), respectively. Both the PPI and VPZ groups had a significantly higher prevalence of gastric mucosal redness compared with the control group (P<0.001). In the multivariate analysis, PPI and VPZ use were significantly associated with gastric mucosal redness. Fundic gland polyps, gastric hyperplastic polyps, multiple white and flat elevated lesions, cobblestone-like mucosa, and stardust gastric mucosa were also significantly associated with PPI and VPZ use in the multivariate analysis. Back-to-back analysis showed that gastric mucosal redness was not seen before starting PPI/VPZ in most patients. The duration of treatment with VPZ was investigated to determine if it affected the prevalence of gastric mucosal redness. There were no significant differences in treatment duration among patients with and without gastric mucosal redness (mean ± standard deviation: 3.0±1.5 vs. 2.5±1.4 years, P=0.077). In conclusion, the prevalence of gastric mucosal redness was low but was associated with PPI and VPZ use.

Background and study aims  Endoscopic submucosal dissection (ESD) is a standard method for minimally invasive resection of superficial gastrointestinal tumors. The pocket creation method (PCM) facilitates ESD regardless of location in the gastrointestinal tract. The aim of this systematic review and meta-analysis is to evaluate the effectiveness and safety of ESD for superficial neoplasms in the upper and lower gastrointestinal tract comparing the PCM to the non-PCM. Methods  Randomized controlled, prospective, and retrospective studies comparing the PCM with the non-PCM were included. Outcomes included en bloc resection, R0 resection, dissection speed, delayed bleeding and perforation. Pooled odds ratios (ORs) with 95 % confidence intervals (CIs) using the Mantel-Haenszel random effect model were documented. Results  Eight studies including gastric, duodenal, and colorectal ESD were included. The en bloc resection rate was significantly higher in the PCM group than the non-PCM group (OR 3.87, 95 %CI 1.24-12.10 P  = 0.020). The R0 resection rate was significantly higher in the PCM group than the non-PCM group (OR 2.46, 95 %CI 1.14-5.30, P  = 0.020). The dissection speed was significantly faster in the PCM group than the non-PCM group (mean difference 3.13, 95 % CI 1.35-4.91, P  < 0.001). The rate of delayed bleeding was similar in the two groups (OR 1.13, 95 %CI 0.60-2.15, P =  0.700). The rate of perforation was significantly lower in the PCM group than the non-PCM group (OR 0.34, 95 %CI 0.15-0.76, P =  0.009). Conclusions  The PCM facilitates high-quality, fast and safe colorectal ESD. Further studies are needed regarding the utility of PCM in ESD of the upper gastrointestinal tract.

Yuki and colleagues report a case of successful endoscopic hemostasis of post-papillectomy bleeding with the gel immersion method and an endoscope with an attached balloon and a cylindrical hood. The visual field was improved with gel and maneuverability was improved using the cylindrical hood and the semi-inflating balloon.

When performing endoscopic reduction in patients with gastric volvulus, it is important to maintain a low level of intragastric pressure and to fix the endoscope in the duodenum. Gel immersion endoscopy is a new method for securing the visual field by injecting clear gel. The balloon-attached endoscope makes it easier to fix the tip in the duodenum without mucosal damage. We report successful reduction of a mesenteroaxial gastric volvulus using an endoscope with a balloon in combination with gel immersion endoscopy. A 3-year-old Japanese male developed gastric volvulus. Since gastric decompression using a nasogastric tube failed to reduce the volvulus, endoscopic reduction was performed under general anesthesia. After aspiration of intragastric gas, clear gel was injected through the accessory channel which secured the visual field in the stomach even with residue while maintaining low intragastric pressure. After reaching the descending portion of the duodenum, the balloon attached to the tip of the endoscope was inflated and fixed in the duodenum. The volvulus was successfully reduced by pulling back the endoscope with clockwise torque. Acute mesenteroaxial gastric volvulus has the potential to cause ischemia and perforation which can be life-threatening, so most patients are treated with surgical intervention. Gel immersion endoscopy is safe and effective to secure the visual field, even in children. Endoscopic reduction may be a viable treatment option for reducing gastric volvulus in non-emergent patients.

BACKGROUND: Helicobacter pylori (H. pylori) eradication success increases the incidence of erosive esophagitis by normalization of gastric acid secretion. The aim of this study is to clarify predictors and timing for the development of symptomatic gastroesophageal reflux disease (GERD) after successful H. pylori eradication based on long-term follow-up. METHODS: From April 2014 to October 2020, 330 patients with H. pylori infections treated with a standard triple-drug regimen were enrolled, and their records retrospectively reviewed. Development of symptomatic GERD was defined as requiring proton pump inhibitor or vonoprazan therapy to treat symptoms. RESULTS: The mean follow-up period was 2.8 years, and symptomatic GERD developed in 41 (12%) patients during the study period. Overall rates of GERD-symptom free patients at 6 months, 1, and 2 years after eradication were 97%, 93%, and 89%, respectively. We evaluated predictors for the development of symptomatic GERD using a Cox proportional hazards regression model. In multivariate analysis, being a current smoker, having functional dyspepsia, hiatal hernia, and severe gastric atrophy were identified as significant predictive factors. The GERD domain score in the Izumo scale was significantly decreased 1 month after vonoprazan therapy consistent with effective treatment of symptomatic GERD. CONCLUSIONS: The rate of development of symptomatic GERD after successful H. pylori eradication is low over long-term follow-up and is easily controlled by vonoprazan therapy. However, patients with smoking habits, functional dyspepsia, hiatal hernia, or severe gastric atrophy should be followed carefully after eradication.

Balloon enteroscopy-assisted endoscopic retrograde cholangiography (BEA-ERC) is useful and feasible in adults with pancreatobiliary diseases, but its efficacy and safety have not been established in pediatric patients. We compared the success rate and safety of BEA-ERC between adults and pediatric patients. This single-center retrospective study reviewed 348 patients (pediatric: 57, adult: 291) with surgically altered gastrointestinal anatomies who underwent BEA-ERC for biliary disorders from January 2007 to December 2019. The success rate of reaching the anastomosis or duodenal papilla was significantly lower in pediatric patients than in adult patients (66.7% vs. 88.0%, p < 0.01). The clinical success rate was also significantly lower in pediatric patients (64.9% vs. 80.4%, p = 0.014). The rate of adverse events was significantly higher in pediatric patients than in adults (14.2% vs. 7.7%, p = 0.037). However, if the anastomotic sites were reached in pediatric patients, the treatment was highly successful (97.3%). The time of reaching target site was significantly longer in pediatric patients than in adult patients. This study shows that BEA-ERC in pediatric patients is more difficult than that in adult patients. However, in patients where the balloon enteroscope was advanced to the anastomosis, clinical outcomes comparable to those in adults can be achieved.

BACKGROUND: This study aimed to compare the markers of potential pancreatic injury during antegrade double-balloon endoscopy (DBE) using the newly developed ultrathin EN-580XP system and the conventional EN-580T system. METHODS: Patients who were scheduled for antegrade DBE during daily clinical practice were enrolled. Clinical background, adverse events, and laboratory data of patients were compared between those who underwent endoscopy using the EN-580XP system and those in whom the EN-580T system was used. The primary end points were pancreatic hyperamylasemia and hyperlipasemia after DBE. RESULTS: A total of 295 cases were registered. Pancreatic hyperamylasemia occurred in 2 of 92 patients (2.2 %) in the EN-580XP group and in 28 of 147 patients (19.1 %) in the EN-580 T diagnosis group (P < 0.001). Hyperlipasemia was significantly different between the two groups (1.1 % [EN-580XP] vs. 13.6 % [EN-580 T diagnosis]; P < 0.001). Acute pancreatitis occurred in four patients (7.1 %) in the EN-580 T therapy group. Multiple logistic regression analyses revealed that the endoscope type EN-580 T was significantly associated with pancreatic hyperamylasemia (adjusted odds ratio [OR] 8.63, 95 % confidence interval [CI] 1.97 - 37.70; P < 0.01) and hyperlipasemia (adjusted OR 13.10, 95 %CI 1.70 - 100.70; P = 0.01). CONCLUSIONS: The EN-580XP system seemed less harmful to the pancreas during antegrade DBE.

Adenocarcinoma in a Meckel's diverticulum is rare and difficult to diagnose preoperatively. We report the first case of a metachronous Krukenberg tumor from adenocarcinoma in a Meckel's diverticulum. A 45-year-old woman was admitted for recurrent abdominal pain. Computed tomography scan showed a lesion with contrast enhancement, and a Meckel's diverticulum-associated tumor was suspected. Double-ballon enteroscopy revealed intestinal stenosis and biopsy showed adenocarcinoma. Operative findings showed a Meckel's diverticulum with tumor. Histopathological evaluation revealed well-differentiated adenocarcinoma, interrupted by ectopic gastric mucosa, diagnosed as adenocarcinoma in a Meckel's diverticulum. Two years postoperatively, a multi-cystic mass with contrast enhancement was observed in the pelvis on imaging evaluation and oophorectomy performed. Histological examination of the resected ovary showed proliferation of atypical glandular ducts, consistent with metastatic adenocarcinoma. This case demonstrates that adenocarcinoma in a Meckel's diverticulum may result in distant metastases and requires appropriate follow-up.

BACKGROUND: To decrease the risk of bleeding or perforation, ischemic polypectomy is performed using a detachable snare or endoclip with double-balloon endoscopy (DBE) for small-bowel polyps in patients with Peutz - Jeghers syndrome. The aim of this study was to determine the effectiveness and feasibility of ischemic polypectomy. METHODS: We retrospectively reviewed patients who underwent two or more sessions of ischemic polypectomy using DBE from July 2004 to August 2017. RESULTS: 67 therapeutic DBEs were performed in nine patients during the study period and 352 polyps were treated. The median observation period was 34 months (range 12 - 66). There was a declining trend over time in the median number of polyps > 15 mm treated per patient first DBE session 6, second 2, third 1.5, fourth 0.5, fifth 0.5; P = 0.11, Friedman test). No patient required laparotomy due to intussusception during the study period. One patient developed mild acute pancreatitis after the procedure. CONCLUSIONS: Ischemic polypectomy was feasible for the control of small-bowel polyps in patients with Peutz - Jeghers syndrome.

Backgrounds and study aims  Gel immersion endoscopy is a novel technique to secure the visual field during endoscopy. The aim of this study was to develop a dedicated gel for this technique. Methods  To identify appropriate viscoelasticity and electrical conductivity, various gels were examined. Based on these results, the dedicated gel "OPF-203" was developed. Efficacy and safety of OPF-203 were evaluated in a porcine model. Results  In vitro experiments showed that a viscosity of 230 to 1900 mPa·s, loss tangent (tanδ) ≤ 0.6, and hardness of 240 to 540 N/cm 2 were suitable. Ex vivo experiments showed electrical conductivity ≤ 220 μS/cm is appropriate. In vivo experiments using gastrointestinal bleeding showed that OPF-203 provided clear visualization compared to water. After electrocoagulation of gastric mucosa in OPF-203, severe coagulative necrosis was not observed in the muscularis but limited to the mucosa. Conclusions  OPF-203 is useful for gel immersion endoscopy.

BACKGROUND : Many patients with familial adenomatous polyposis (FAP) have adenomatous polyps of the duodenum and the jejunum. We aimed to elucidate the long-term outcomes after double-balloon endoscopy (DBE)-assisted endoscopic resection of duodenal and jejunal polyps in patients with FAP. METHODS : We retrospectively reviewed patients who underwent more than two sessions of endoscopic resection using DBE from August 2004 to July 2018. RESULTS : A total of 72 DBEs were performed in eight patients (median age 30 years, range 12-53; 1.4 DBE procedures/patient-year) during the study period, and 1237 polyps were resected. The median observation period was 77.5 months (range 8-167). There were 11 adverse events, including seven delayed bleeds and four episodes of acute pancreatitis. No delayed bleeding occurred after cold polypectomy. Although, in one patient, one endoscopically resected duodenal polyp was diagnosed as being intramucosal carcinoma, none of the patients developed an advanced duodenal or jejunal cancer during the study period. CONCLUSIONS : Endoscopic resection of duodenal and jejunal polyposis using DBE in patients with FAP can be performed safely, efficiently, and effectively.