Background/Aims: Tegoprazan is a novel potassium-competitive acid blocker that has beneficial effects on acid-related disorders such as gastroesophageal reflux and peptic ulcer diseases.This study aimed to validate the effect of tegoprazan on endoscopic submucosal dissection (ESD)-induced artificial ulcers. Methods: Patients from 16 centers in Korea who underwent ESD for gastric neoplasia were enrolled. After ESD, pantoprazole was administered intravenously for 48 hours. The patients were randomly allocated to either the tegoprazan or esomeprazole group. Tegoprazan 50 mg or esomeprazole 40 mg were administered for 4 weeks, after which gastroscopic evaluation was performed. If the artificial ulcer had not healed, the same dose of tegoprazan or esomeprazole was administered for an additional 4 weeks, and a gastroscopic evaluation was performed. Results: One hundred sixty patients were enrolled in this study. The healing rates of artificial ulcers at 4 weeks were 30.3% (23/76) and 22.1% (15/68) in the tegoprazan and esomeprazole groups, respectively (p=0.006). At 8 weeks after ESD, the cumulative ulcer healing rates were 73.7% (56/76) and 77.9% (53/68) in the tegoprazan and esomeprazole groups, respectively (p=0.210). Delayed bleeding occurred in two patients in the tegoprazan group (2.6%) and in one patient in the esomeprazole group (1.5%). Other adverse events were negligible in both groups. Conclusions Tegoprazan showed similar effects on post-ESD artificial ulcer healing in comparison with esomeprazole.

Background/Aims: We examined the efficacy and safety of tegoprazan as a part of first-line triple therapy for Helicobacter pylori eradication. Methods: A randomized, double-blind, controlled, multicenter study was performed to evaluate whether tegoprazan (50 mg)-based triple therapy (TPZ) was noninferior to lansoprazole (30 mg)-based triple therapy (LPZ) (with amoxicillin 1 g and clarithromycin 500 mg; all administered twice daily for 7 days) for treating H. pylori. The primary endpoint was the H. pylori eradication rate. Subgroup analyses were performed according to the cytochrome P450 (CYP) 2C19 genotype, the minimum inhibitory concentration (MIC) of amoxicillin and clarithromycin, and underlying gastric diseases. Results: In total, 350 H. pylori-positive patients were randomly allocated to the TPZ or LPZ group. The H. pylori eradication rates in the TPZ and LPZ groups were 62.86% (110/175) and 60.57% (106/175) in an intention-to-treat analysis and 69.33% (104/150) and 67.33% (101/150) in a per-protocol analysis (non-inferiority test, p=0.009 and p=0.013), respectively. Subgroup analyses according to MICs or CYP2C19 did not show remarkable differences in eradication rate. Both first-line triple therapies were well-tolerated with no notable differences. Conclusions TPZ is as effective as proton pump inhibitor-based triple therapy and is as safe as first-line H. pylori eradication therapy but does not overcome the clarithromycin resistance of H. pylori in Korea

Background/Aims: Nutritional status influences quality of life among patients with inflammatory bowel disease (IBD), although there is no clear method to evaluate nutritional status in this setting. Therefore, this study examined whether bioelectrical impedance analysis (BIA) could be used to evaluate the nutritional status of patients with IBD. Methods: We retrospectively analyzed data from 139 Korean patients with IBD who were treated between November 2018 and November 2019. Patients were categorized as having active or inactive IBD based on the Harvey-Bradshaw index (a score of ≥5 indicates active Crohn’s disease) and the partial Mayo scoring index (a score of ≥2 indicates active ulcerative colitis). BIA results and serum nutritional markers were analyzed according to disease activity. Results: The mean patient age was 45.11±17.71 years. The study included 47 patients with ulcerative colitis and 92 patients with Crohn’s disease. Relative to the group with active disease (n=72), the group with inactive disease (n=67) had significantly higher values for hemoglobin (P<0.001), total protein (P<0.001), and albumin (P<0.001). Furthermore, the group with inactive disease had higher BIA values for body moisture (P=0.047), muscle mass (P=0.046), skeletal muscle mass (P=0.042), body mass index (P=0.027), and mineral content (P=0.034). Moreover, the serum nutritional markers were positively correlated with the BIA results. Conclusions Nutritional markers evaluated using BIA were correlated with serum nutritional markers and inversely correlated with disease activity. Therefore, we suggest that BIA may be a useful tool that can help existing nutritional tests monitor the nutritional status of IBD patients.

Background/Aims: Recently, 1-L polyethylene glycol-ascorbic acid (PEG-Asc) has been used to reduce the volume of preparation agents in colonoscopy. This clinical trial aimed to compare the efficacy and safety of two types of 1-L PEG-Asc (CleanViewAL ® [Tae Joon Pharmaceutical Company, Seoul, Korea] and Plenvu ® [Norgine, Harefield, United Kingdom]) in average-aged adults. Methods: This study was a prospective, randomized, non-inferiority, open-label, phase 4 clinical trial. The primary endpoint was the efficacy evaluated using the Boston bowel preparation scale (BBPS), and the secondary endpoint was clinical safety. Results: In total, 173 patients were assigned to either the CleanViewAL ® (n=84) or Plenvu ® (n=89) group. Overall cleansing successes of 97.6% (82/84) and 98.8% (88/89) were achieved in the CleanViewAL ® group and in the Plenvu ® group, respectively, showing that CleanViewAL ® has similar bowel cleansing efficacy to Plenvu ® (95% CI, -0.052 to 0.027; p=0.207). The total BBPS score was 8.67±1.00 and 8.70±0.76 in the CleanViewAL ® group and Plenvu ® group, respectively (p=0.869). The most common adverse symptom was nausea, and no adverse symptoms requiring hospitalization were reported in either group. There were no cases of critical hypernatremia and liver dysfunction exceeding the common terminology criteria for adverse events grade I. An overall satisfaction score (scale of 1 to 10) showed no difference between the two groups (p=0.289). However, the CleanViewAL ® group showed a higher taste satisfaction score (scale of 1 to 5) than the Plenvu ® group (CleanViewAL ® : 2.90±0.91, Plenvu ® : 2.60±0.86, p=0.028). Conclusions Both types of 1-L PEG-Asc, CleanViewAL ® and Plenvu ® , are effective and safe bowel cleansing agents in average-aged adults. CleanViewAL ® was preferred in terms of taste satisfaction.

Background/Aims: There is a recent increase in the use of stool multiplex PCR assay-based diagnostic tests in patients with acute diarrhea. We used multiplex PCR assays to analyze the distribution of diarrhea-causing bacteria and viruses, as well as the clinical features of patients with acute diarrhea. Methods: We retrospectively reviewed stool specimens of inpatients complaining of acute diarrhea from October 2018 to July 2020.The stool specimens had been tested for bacteria and viruses using multiplex PCR assays. Results: A total of 414 stool specimens from 346 patients were tested, and 152 pathogens were detected in 131 stool samples (131/414, 31.6%). Co-infection was detected in 20 patients (20/346, 5.8%). The common pathogens detected as causes of acute diarrhea, including co-infection, were Clostridium perfringens (34.9%), Clostridioides difficile (19.7%), and Campylobacter spp. (18.4%). The average age of patients with multiplex PCR-positive tests was lower than those with multiplex PCR-negative tests (p=0.001). In patients with suspected C. difficile infection (CDI), the RT-PCR for toxin gene assay was performed in 370 stool samples, 35 of which were positive (9.5%). Furthermore, 16 of the 35 samples were positive on the multiplex PCR assay (45.7%). Conclusions The multiplex PCR assay revealed that C. perfringens was the most common diarrhea-causing pathogen. In addition, in patients with suspected CDI, the multiplex PCR assay alone was insufficiently sensitive to detect pathogens and a conventional CDI test was additionally required.

The pegylated interferon plus ribavirin combination therapy has been used as the primary treatment for chronic hepatitis C (CHC) but fails to produce a sustained viral response (SVR) in many patients. In recent years, the treatment of CHC has been rapidly changing because of the introduction of direct-acting antivirals (DAAs), which have a high cure rate. However, retreatment of patients after failure of the first DAA therapy is difficult. We report two rare cases of CHC that showed acquired SVR with other DAA combinations after failure to daclatasvir and asunaprevir.

Background/Aims: The utility of endoscopic ultrasonography (EUS) for differentiating gastrointestinal stromal tumors (GISTs) and leiomyomas of the stomach is not well known. We aimed to evaluate the ability of EUS for differentiating gastric GISTs and leiomyomas. Methods: We retrospectively reviewed the medical records of patients with histopathologically proven GISTs (n=274) and leiomyomas (n=87). In two consensus meetings, the inter-observer variability in the EUS image analysis was reduced. Using logistic regression analyses, we selected predictive factors and constructed a predictive model and nomogram for differentiating GISTs from leiomyomas. A receiver operating characteristic (ROC) curve analysis was performed to measure the discrimination performance in the development and internal validation sets. Results: Multivariate analysis identified heterogeneity (odds ratio [OR], 9.48), non-cardia (OR, 19.11), and older age (OR, 1.06) as independent predictors of GISTs. The areas under the ROC curve of the predictive model using age, sex, and four EUS factors (homogeneity, location, anechoic spaces, and dimpling or ulcer) were 0.916 (sensitivity, 0.908; specificity, 0.793) and 0.904 (sensitivity, 0.908; specificity, 0.782) in the development and internal validation sets, respectively. Conclusions The predictive model and nomogram using age, sex and homogeneity, tumor location, presence of anechoic spaces, and presence of dimpling or ulcer on EUS may facilitate differentiation between GISTs and leiomyomas.

The rupture of a pyogenic liver abscess (PLA) with peritonitis is a rare occurrence but a surgical emergency with a high mortality rate in the case of gas-forming PLA. Rare cases of ruptured PLA that recovered completely with only medical treatment have been reported.This paper reports a case of a large PLA rupture with peritonitis. In this case, surgical intervention was too risky because of the patient’s age and poor general condition. The patient recovered fully with appropriate antibiotic therapy and sufficient percutaneous drainage. Therefore, medical treatment may be considered an alternative option in cases of a ruptured large PLA with peritonitis if surgical intervention is too risky.

The rupture of a pyogenic liver abscess (PLA) with peritonitis is a rare occurrence but a surgical emergency with a high mortality rate in the case of gas-forming PLA. Rare cases of ruptured PLA that recovered completely with only medical treatment have been reported.This paper reports a case of a large PLA rupture with peritonitis. In this case, surgical intervention was too risky because of the patient’s age and poor general condition. The patient recovered fully with appropriate antibiotic therapy and sufficient percutaneous drainage. Therefore, medical treatment may be considered an alternative option in cases of a ruptured large PLA with peritonitis if surgical intervention is too risky.

A visceral artery pseudoaneurysm after ERCP is a rare adverse event that is potentially life-threatening. Most cases reported previously originated from the peripancreatic arteries, including the splenic artery, gastroduodenal artery, or pancreaticoduodenal artery. The mechanism of the occurrence of visceral artery pseudoaneurysms after ERCP has not been elucidated until now. Recently, a pseudoaneurysm rupture originating from the superior mesenteric artery after ERCP was observed in a patient without a history of pancreatitis. This paper reports this case with a review of the relevant literature.