Search

Bezoars, including phytobezoars, trichobezoars, and pharmacobezoars, are accumulations of undigested substances in the gastrointestinal tract. We report three cases of gastric bezoars. Case 1: An 86-year-old woman presented with a one-month history of abdominal pain and vomiting. Esophagogastroduodenoscopy revealed gastric bezoars; consumption of 2 L of cola daily for 2 weeks resulted in complete disappearance of the bezoars. Case 2: An asymptomatic 63-year-old woman underwent esophagogastroduodenoscopy, which revealed a gastric bezoar. Cola spraying and endoscopic lithotomy were ineffective; therefore, the patient underwent laparoscopic removal of the bezoar for management of small bowel obstruction secondary to the bezoar fragments. Case 3: A 6-year-old girl with a history of pica underwent two laparoscopic surgeries 10 months apart for recurrent trichobezoars. We report our treatment approach in three patients who presented with gastric bezoars.

Background/Aims: The impact of sedation on cardio-cerebrovascular (CCV) adverse events after esophagogastroduodenoscopy (EGD) in patients with gastric cancer (GC) is unclear. We investigated the incidence rate and impact of sedation on CCV adverse events after surveillance EGD in patients with GC. Methods : We performed a nationwide population-based cohort study using the Health Insurance Review and Assessment Service databases from January 1, 2018, to December 31, 2020. Using a propensity score-matched analysis, patients with GC were divided into two groups: sedative agent users and nonusers for surveillance EGD. We compared the occurrence of CCV adverse events within 14 days between the two groups. Results : Of the 103,463 patients with GC, newly diagnosed CCV adverse events occurred in 2.57% of patients within 14 days after surveillance EGD. Sedative agents were used in 41.3% of the patients during EGD. The incidence rates of CCV adverse events with and without sedation were 173.6/10,000 and 315.4/10,000, respectively. Between sedative agent users and nonusers based on propensity score matching (28,008 pairs), there were no significant differences in the occurrence of 14-day CCV, cardiac, cerebral, and other vascular adverse events (2.28% vs 2.22%, p=0.69; 1.44% vs 1.31%, p=0.23; 0.74% vs 0.84%, p=0.20; 0.10% vs 0.07%, p=0.25, respectively). Conclusion : s: Sedation during surveillance EGD was not associated with CCV adverse events in patients with GC. Therefore, the use of sedative agents may be considered in patients with GC during surveillance EGD without excessive concerns about CCV adverse events.

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. Conclusion : s: Tegoprazan showed similar effects on post-ESD artificial ulcer healing in comparison with esomeprazole.

Background/Aims Metachronous gastric cancer (MGC) can occur after endoscopic resection for gastric cancer. Further studies on factors other than Helicobacter pylori infection are needed. This systematic review and meta-analysis aimed to evaluate risk factors for metachronous recurrence of endoscopically resected gastric cancer. Methods We searched medical literature published by February 2023 and identified patients with MGC after endoscopic resection for gastric cancer. The occurrence of MGC and the presence of intestinal metaplasia (IM), severe atrophic gastritis (AG), and H. pylori infection were quantitatively analyzed. Results We identified 2,755 patients from nine cohort studies who underwent endoscopic resection for gastric cancer by 2018. Those with severe AG or presence of IM had a significantly higher incidence of MGC than those without (RR 2.00, 95% CI 1.35–2.98, I2 = 52% for severe atrophy on antrum; RR 7.08, 95% CI 3.63–13.80, I2 = 0% for antral IM). Absolute risk difference of MGC occurrence was 7.1% in those with severe AG and 9.2% in those with IM. The difference in incidence rate per 1,000 person-years was 17.5 person-years for those with severe AG and 24.7 person-years for those with IM. However, H. pylori eradication did not significantly affect the occurrence of MGC (RR 1.18, 95% CI 0.88–1.59, I2 = 10%). Conclusions Gastric cancer patients with severe AG or presence of IM had a 2.0-fold or 7.0-fold higher risk of MGC occurrence after endoscopic resection than those without, respectively. They need more stringent follow-up to monitor MGC occurrences (CRD42023410940).

A 51-year-old man with a 10-day history of acute-onset dysphagia presented with inability to swallow anything orally. The patient was unable to swallow any radiopaque contrast medium; therefore, a videofluoroscopic swallow study could not be performed. Brain imaging, neurological findings, and initial endoscopy findings were normal. Neck computed tomography suggested left vocal cord paralysis. The patient was diagnosed with diabetes one year prior to presentation but did not receive any treatment. Insulin therapy during hospitalization controlled the patient’s blood glucose levels, and his symptoms improved without any sequelae. We present a rare case of vocal cord paralysis secondary to controlled diabetes. The initial endoscopic examination did not include thorough evaluation of the vocal cords; therefore, accurate diagnosis was challenging in this case.

Background/Aims: Dual priming oligonucleotide-based multiplex polymerase chain reaction (DPO-PCR) has recently been used for both the detection of Helicobacter pylori and the identification of H. pylori 23S ribosomal RNA point mutations that cause clarithromycin resistance. The aim of this study was to investigate the duration of effective standard triple therapy in a clarithromycin susceptible group and of bismuth-based quadruple therapy in a resistant group based on DPO-PCR. Methods: We retrospectively analyzed the electronic medical records of 184 patients who, between September 2019 and December 2020, received eradication therapy following detection of H. pylori, and the subsequent identification of the clarithromycin susceptibility of their H. pylori using DPO-PCR. Patients were treated with 7- or 14-day standard triple therapy in the clarithromycin susceptible group, whereas 7- or 14-day bismuth-based quadruple therapy in the clarithromycin resistance group. Results: In the clarithromycin susceptible group, per-protocol analyses showed eradication rates of 87.5% (42/48; 95% confidence interval [CI], 77.1% to 95.8%) for 7-day therapy and 87.2% (41/47; 95% CI, 78.7% to 95.7%) for 14-day therapy (p=0.969). The eradication rates in the clarithromycin resistance group were 91.4% (32/35; 95% CI, 80.0% to 100.0%) for 7-day therapy and 90.3% (28/31; 95% CI, 77.4% to 100.0%) for 14-day therapy (p=0.876). There was no significant difference in the eradication rates, patient compliance, or rate of adverse events between the 7- and 14-day therapies for both groups. Conclusions: Compared to the 14-day therapy, 7-day eradication therapy is sufficient after DPO-PCR-based clarithromycin susceptibility testing.

Abstract Radiative cooling is a passive cooling technology without any energy consumption, compared to conventional cooling technologies that require power sources and dump waste heat into the surroundings. For decades, many radiative cooling studies have been introduced but its applications are mostly restricted to nighttime use only. Recently, the emergence of photonic technologies to achieves daytime radiative cooling overcome the performance limitations. For example, broadband and selective emissions in mid-IR and high reflectance in the solar spectral range have already been demonstrated. This review article discusses the fundamentals of thermodynamic heat transfer that motivates radiative cooling. Several photonic structures such as multilayer, periodical, random; derived from nature, and associated design procedures were thoroughly discussed. Photonic integration with new functionality significantly enhances the efficiency of radiative cooling technologies such as colored, transparent, and switchable radiative cooling applications has been developed. The commercial applications such as reducing cooling loads in vehicles, increasing the power generation of solar cells, generating electricity, saving water, and personal thermal regulation are also summarized. Lastly, perspectives on radiative cooling and emerging issues with potential solution strategies are discussed.

Abstract Background Identifying clarithromycin resistance is essential for eradicating Helicobacter pylori (HP). Therefore, we evaluated the performance of Allplex™ H.pylori & ClariR Assay (Allplex™) for diagnosing and detecting clarithromycin resistance in HP. Methods Subjects who underwent esophagogastroduodenoscopy between April 2020 and August 2021 at Incheon St. Mary’s hospital were enrolled in this study. The diagnostic performances of Allplex™ and dual priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) were compared with sequencing as the gold standard. Results A total of 142 gastric biopsy samples were analyzed. Gene sequencing revealed 124 HP infections, 42 A2143G mutations, 2 A2142G mutations, one dual mutation, and no A2142C mutation. DPO-PCR showed 96.0% sensitivity and 100.0% specificity for HP detection; the corresponding rates for Allplex™ were 99.2% and 100.0%. DPO-PCR showed 88.3% sensitivity and 82.0% specificity for A2143G mutation, and Allplex™ showed 97.6% and 96.0%. The Cohen’s Kappa coefficient for overall test results was 0.56 for DPO-PCR and 0.95 for Allplex™. Conclusion Allplex™ showed comparable diagnostic performance with direct gene sequencing and non-inferior diagnostic performance to DPO-PCR. Further research is required to confirm whether Allplex™ is an effective diagnostic tool for the eradication of HP.

Gastric subepithelial tumors (SETs) are usually asymptomatic and are often detected incidentally during screening endoscopy. A gastric inverted hyperplastic polyp (IHP) is characterized by downward growth of hyperplastic mucosa into the submucosal layer. Owing to these characteristics, a gastric IHP is frequently misdiagnosed as a SET. Gastric IHPs are asymptomatic in most cases and are discovered incidentally. Notably, IHPs may be accompanied by an adenocarcinoma or anemia owing to chronic bleeding associated with this lesion; therefore, endoscopic submucosal dissection is recommended for complete excision of IHPs measuring > 2 cm. We report a case of gastric IHP that was diagnosed during screening endoscopy in an asymptomatic patient. We observed a whitish purulent exudate expressed from the SET, and endoscopic ultrasonography revealed a SET originating from the muscularis mucosa. Endoscopic submucosal dissection was performed to remove the SET, and final histopathological findings revealed a gastric IHP. This case report highlights that IHPs should be suspected in patients with a SET associated with whitish exudates.

This study proposes a rectangular-shaped optical module capable of simultaneously implementing crop cultivation and solar power generation. By employing a cylindrical Fresnel lens (CFL) array plate with a size of 100 × 100 mm2, multiple focal lines are formed, where some of the incident light transmits through the module while the rest is guided laterally through the rectangular lightguide structure. This guided sunlight is then concentrated by a cylindrical compound parabolic concentrator (CCPC) structure, resulting in a 20-fold concentration ratio, onto a 5 × 100 mm2 Si photovoltaic (PV) cell. To experimentally verify feasibility, both the CFL array plate and the lightguide plate were fabricated with three-axis machine tooling equipment and assembled. The power generated experimentally by the 5 × 100 mm2 Si PV cell was 54% of the expected value from the simulation results on the light-concentrated efficiency considering experimental conditions, while the results on experimental transmittance along with rotation angles were very close to the simulation results. However, overall, the tendency of the generated power along the rotation angles is close to the tendency of the light-concentrated efficiency along the rotation angles from the simulation. Additionally, this study dealt with further consideration to enhance light-concentrated efficiency, introducing a means to adjust the trade-off relationship between transmittance and light-concentrated efficiency.

Background/Aims: This study aimed to determine changes in endoscopist-driven sedation practices 5 years after the first nationwide survey in 2014 by the Korean Society of Gastrointestinal Endoscopy (KSGE). Methods: A 59-item survey covering current practices was electronically mailed to all members of the KSGE in 2019. Results: In total, 955 (12.8%) out of 7,486 questionnaires were returned. A total of 738 (77.7%) out of 955 respondents attended dedicated sedation education programs. The American Society of Anesthesiologists class was recorded by 464 (51.2%) out of 907 respondents. The recording rate was higher in respondents who completed sedation education (p=0.014) and worked in general or tertiary hospitals (p

Procedural sedation has become increasingly common in endoscopy. Sedatives and analgesics induce anxiolysis and amnesia. In addition, an appropriate level of sedation is necessary for safe procedures including therapeutic endoscopy. Midazolam and propofol are the most commonly used drugs in sedative endoscopy. In recent years, the need to ascertain the safety and effectiveness of sedation has increased in practice. Therefore, new sedatives and analgesic drugs for optimal sedative endoscopy, have recently emerged. This article reviews the characteristics of sedatives and analgesics, and describes their clinical use in gastrointestinal endoscopy.

Abstract Recent technological advances have re‐invigorated the interest in nuclear translation (NT), but the underlying mechanisms and functional implications of NT remain unknown. Here we show that NT is enhanced in malignant cancer cells and is associated with rapid cell growth. Nuclear ribopuromycylation analyses in a panel of diverse cell lines revealed that NT is scarce in normal immortalized cells, but is ubiquitous and robust in malignant cancer cells. Moreover, NT occurs in the nucleolus and requires normal nucleolar function. Intriguingly, NT is reduced by cellular stresses and anti‐tumor agents and positively correlates with cancer cell proliferation and growth. By using a modified puromycin‐associated nascent chain proteomics, we further identified numerous oncoproteins that are preferentially translated in the nucleus, such as transforming growth factor‐beta 2 (TGFB2) and nucleophosmin 1 (NMP1). Specific overexpression of TGFB2 and NMP1 messenger RNAs in the nucleus can increase their protein levels and promote tumorigenesis. These findings establish a previously unknown link between NT and malignancy and suggest that cancer cells might have adapted a mechanism of NT to support their need for rapid growth, which highlight the potential of NT in tumorigenesis and might also open up new possibilities for therapeutic targeting of cancer‐specific cellular functions.

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 (ClinicalTrials.gov identifier NCT03317223).

Background/Aims: Globally, the population aged 80 years or older is growing faster due to the rising life expectancy. Korea has already entered into an advanced aged society, and a post-aged society is expected in 2025. This study evaluated the patterns of gastrointestinal disease in the population aged 80 years or older during the recent decade in Korea. Method: This study retrospectively reviewed the medical records of patients admitted to the gastrointestinal department of Suwon St. Vincent’s hospital, Incheon St. Mary’s hospital, and Uijeongbu St. Mary's Hospital ― general hospitals of Seoul-Gyeonggi province in Korea. It was a repeated cross-sectional study in 2009 and 2019. Results: The number of admitted patients aged 80 years or older increased from 549 (9.0%) in 2009 to 1,073 (14.4%) in 2019 (p

CDK2 can drive the proliferation of cancer cells. Here, the authors screened for a non-ATP competitive inhibitor of the CDK2/cylinA complex and find that Homoharringtonine can disrupt the complex and promote the degradation of CDK2.

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing. The patient should maintain a state of consciousness to the extent that he or she can cooperate with the needs of the medical staff. Despite its benefits, endoscopic sedation has been associated with cardiopulmonary complications. Such cardiopulmonary complications are usually temporary, and most patients recover without sequelae. However, these events may progress to serious complications, such as cardiovascular collapse. Therefore, it is essential to screen high-risk patients before sedation and reduce complications by meticulous monitoring. Additionally, physicians should be familiar with the management of emergencies. The first Korean clinical practice guideline for endoscopic sedation was developed based on previous worldwide guidelines for endoscopic sedation using an adaptation process. The guideline consists of nine recommendations based on a critical review of currently available data and expert consensus when the guideline was drafted. These guidelines should provide clinicians, nurses, medical school students, and policy makers with information on how to perform endoscopic sedation with minimal risk.

Background/Aims The efficacy of propofol in gastrointestinal endoscopy for patients with midazolam-induced paradoxical reactions remains unclarified. This study aimed to compare the efficacy and safety of propofol-based sedation in patients who previously experienced paradoxical reactions. Methods This was a prospective, single-blinded, randomized controlled pilot study. Participants with a history of paradoxical reactions to midazolam during a previous esophagogastroduodenoscopy were recruited and randomly assigned to group I (propofol monosedation) or group II (combination of propofol and midazolam). The primary endpoint was the occurrence of a paradoxical reaction. Results A total of 30 participants (mean age, 54.7±12.6 years; male, 19/30) were randomly assigned to group I (n=16) or group II (n=14). There were no paradoxical reactions in group I, but there were two in group II, without a significant difference (p=0.209). The mean dose of propofol was higher in group I than in group II (p=0.002). Meanwhile, the procedure and recovery times did not differ between groups. Conclusions Propofol-based sedation was safe and effective for patients who experienced paradoxical reactions to midazolam. However, caution is needed because few cases of paradoxical reaction again can happen in group II in which midazolam was readministered.

Background/Aims This study aimed to determine the current status of facilities, equipment, and personnel for endoscopic sedation from endoscopy units of representative hospitals in South Korea. Methods A questionnaire survey was conducted on 50 qualified endoscopy units accredited by the Korean Society of Gastrointestinal Endoscopy. Results All included endoscopy units had regulations and educational programs regarding sedation training for endoscopists and nursing personnel. There present one assisting nurse during endoscopy in 35 units (70%) and at least two nurses in 12 units (24.0%). All endoscopy units had examination rooms equipped with oxygen supply and suction systems. Endoscopist-directed sedation was performed in 48 units (96.0%). Propofol-based sedation was the most used sedation method. All units had a separate recovery bay. The daily number of patients per bed was greater than 10 in 17 units (34.0%). In 26 (52.0%) units, a single nurse cared for ≥10 patients per day. All the units fulfilled the discharge criteria. Conclusions This study presents data regarding endoscopic sedation clinical practice in 50 endoscopy units in South Korea. This study presents the current status of endoscopic sedation clinical practice in 50 qualified endoscopy units accredited by the KSGE, which provide excellent quality management.

Background/Aims: The mucoprotective drug rebamipide is used to treat gastritis and peptic ulcers. We compared the efficacy of MucostaⓇ (rebamipide 100 mg) and its new formulation, AD-203 (rebamipide 150 mg), in treating erosive gastritis. Methods: This double-blind, active control, noninferiority, multicenter, phase 3 clinical trial randomly assigned 475 patients with endoscopically proven erosive gastritis to two groups: AD-203 twice daily or MucostaⓇ thrice daily for 2 weeks. The intention-to-treat (ITT) analysis included 454 patients (AD-203, n=229; MucostaⓇ, n=225), and the per-protocol (PP) analysis included 439 patients (AD-203, n=224; MucostaⓇ, n=215). The posttreatment assessments included the primary (erosion improvement rate) and secondary endpoints (erosion and edema cure rates; improvement rates of redness, hemorrhage, and gastrointestinal symptoms). Drug-related adverse events were evaluated. Results: According to the ITT analysis, the erosion improvement rates (posttreatment) in AD-203-treated and MucostaⓇ-treated patients were 39.7% and 43.8%, respectively. According to the PP analysis, the erosion improvement rates (posttreatment) in AD-203-treated and MucostaⓇ-treated patients were 39.3% and 43.7%, respectively. The one-sided 97.5% lower limit for the improvement rate difference between the study groups was −4.01% (95% confidence interval [CI], –13.09% to 5.06%) in the ITT analysis and −4.44% (95% CI, –13.65% to 4.78%) in the PP analysis. The groups did not significantly differ in the secondary endpoints in either analysis. Twenty-four AD-203-treated and 20 MucostaⓇ-treated patients reported adverse events but no serious adverse drug reactions; both groups presented similar adverse event rates. Conclusions: The new formulation of rebamipide 150 mg (AD-203) twice daily was not inferior to rebamipide 100 mg (MucostaⓇ) thrice daily. Both formulations showed a similar efficacy in treating erosive gastritis.

Background/Aims Endoscopic resection (ER) has recently been accepted as the standard treatment modality for superficial non-ampullary duodenal tumors (SNADTs). However, the procedure can cause adverse events such as perforation and bleeding. This study aimed to investigate the efficacy of prophylactic clipping in the prevention of delayed complications. Methods A retrospective review of the medical records of patients who underwent ER for SNADT from 3 centers was performed. Patients were divided into 2 groups: the immediate clipping group (ICG) and the no clipping group (NCG). Various baseline characteristics and factors associated with the appearance of delayed complications, such as size of the lesion, tumor location, histologic type, and co-morbidities, were compared between the two groups. Results A total of 99 lesions from 99 patients were included in this study. Fifty-two patients were allocated into ICG and 47 patients were allocated into NCG. Delayed bleeding occurred in 1 patient from ICG and in 8 patients from NCG. Delayed perforation occurred in 1 patient from ICG and in 3 patients from NCG. There were no procedure-related deaths in both groups. Conclusions Although the use of endoscopic clipping seemed to reduce the risk of developing delayed complications, further studies using a prospective design is required.

Background/Aims The use of endoscopic submucosal dissection (ESD) for treating undifferentiated-type early gastric cancer is controversial. The objective of this study was to perform a meta-analysis to compare the long-term outcomes of ESD and surgery for undifferentiated-type early gastric cancer. Methods The PubMed, Cochrane Library, and EMBASE databases were used to search for relevant studies comparing ESD and surgery for undifferentiated-type early gastric cancer. The methodological quality of the included publications was evaluated using the Risk of Bias Assessment tool for Nonrandomized Studies. The rates of overall survival, recurrence, adverse event, and complete resection were determined. Odds ratios (ORs) and 95% confidence intervals (CIs) were also evaluated. Results This meta-analysis enrolled five studies with 429 and 1,236 participants undergoing ESD and surgery, respectively. No significant difference was found in the overall survival rate between the ESD and surgery groups (OR, 2.29; 95% CI, 0.98–5.36; p=0.06). However, ESD was associated with a higher recurrence rate and a lower complete resection rate. The adverse event rate was similar between the two groups. Conclusions ESD with meticulous surveillance esophagogastroduodenoscopy may be as effective and safe as surgery in patients with undifferentiated-type early gastric cancer. Further large-scale, randomized, controlled studies from additional regions are required to confirm these findings.

Korean guidelines for nonsteroidal anti-inflammatory drug (NSAID)-induced peptic ulcer were previously developed in 2009 with the collaboration of the Korean College of Helicobacter and Upper Gastrointestinal Research and Korean Society of Gastroenterology. However, the previous guidelines were based mainly upon a review of the relevant literature and expert opinion. Therefore, the guidelines need to be revised. We organized a guideline Development Committee for drug-related peptic ulcer under the auspices of the Korean College of Helicobacter and Upper Gastrointestinal Research in 2017 and developed nine statements, including four for NSAIDs, three for aspirin and other antiplatelet agents, and two for anticoagulants through a de novo process founded on evidence-based medicine that included a literature search and a meta-analysis, A consensus was reached through the application of the modified Delphi method. The primary target of these guidelines is adult patients undergoing long-term treatment with NSAIDs, aspirin or other antiplatelet agents and anticoagulants. The revised guidelines reflect the expert consensus and is intended to assist clinicians in the management and prevention of druginduced peptic ulcer and associated conditions.

The Korean guidelines for nonsteroidal anti-inflammatory drug (NSAID)-induced peptic ulcers were previously developed under co-work with the Korean College of Helicobacter and Upper Gastrointestinal Research and Korean Society of Gastroenterology at 2009. On the other hand, the previous guidelines were based mainly on a literature review and expert opinions. Therefore, the guidelines need to be revised. In this study, a guideline development committee for drug-induced peptic ulcers was organized under the Korean College of Helicobacter and Upper Gastrointestinal Research in 2017. Nine statements were developed, including four for NSAID, three for aspirin and other antiplatelet agents, and two for anticoagulants through de novo processes based on evidence-based medicine, such as a literature search, meta-analysis, and the consensus was established using the modified Delphi method. The primary target of this guideline was adult patients taking long-term NSAIDs, aspirin, or other antiplatelet agent and anticoagulants. The revised guidelines reflect the consensus of expert opinions and are intended to assist relevant clinicians in the management and prevention of drug-induced peptic ulcers and associated conditions.

Background/Aims For systematic screening protocol for the stomach (SSS), 22 gastroscopy images are considered sufficient to avoid blind spots during gastroscopy. The aim of this study was to investigate the relationship between the number of gastroscopy images taken during the gastroscopy procedure and the detection rate of clinically significant gastric lesions (CSGLs). Materials and Methods We retrospectively reviewed the data obtained from a cohort of consecutive subjects at a health promotion center. The primary outcome measure was the detection rate of CSGLs per endoscopist, according to the number of gastroscopy images. We also analyzed whether all the CSGLs were detected via SSS. Results The mean number of gastroscopy images obtained by eight endoscopists was 27.6±10.5 in 2,912 subjects without CSGLs and without biopsies. Among the 5,970 subjects who underwent gastroscopy by the eight endoscopists, 712 CSGLs were detected in 551 subjects. Fifty-six CSGLs (7.9%) in 55 subjects (10.0%) were not detected during the SSS. Photo-endoscopists who took more images achieved a higher detection rate of CSGLs than those who took fewer images (adjusted OR 2.07, 95% CI 1.41~3.05; P

Nonvariceal upper gastrointestinal bleeding (NVUGIB) refers to bleeding that develops in the gastrointestinal tract proximal to the ligament of Treitz. NVUGIB requires hospitalization and is associated with significant morbidity and mortality. Although European and Asian-Pacific guidelines have been published, there have been no previous guidelines regarding management of NVUGIB in Korea. Korea has a high prevalence of Helicobacter pylori infections, and patients have easy accessibility to endoscopy. Therefore, we believe that guidelines regarding management of NVUGIB in Korea are essential. The Korean Society of Gastroenterology reviewed the recent evidence and recommends practical management guidelines on NVUGIB in Korea.

Non-variceal upper gastrointestinal bleeding (NVUGIB) refers to bleeding that develops in the gastrointestinal tract proximal to the ligament of Treitz. NVUGIB is an important cause for visiting the hospital and is associated with significant morbidity and mortality. Although European and Asian-Pacific guidelines have been published, there has been no previous guidelines regarding management of NVUGIB in Korea. Korea is a country with a high prevalence of Helicobacter pylori infection and patients have easy accessibility to receive endoscopy. Therefore, we believe that guidelines regarding management of NVUGIB are mandatory. The Korean Society of Gastroenterology reviewed recent evidence and recommends practical management guidelines on NVUGIB in Korea.

Background/Aims Predicting histological ulceration in early gastric cancer (EGC) during endoscopic examination is crucial for endoscopists deciding on the treatment modality. The aim of this study was to investigate the endoscopic factors that can predict histological ulcerations in EGCs. Methods We retrospectively analyzed patients who underwent endoscopic submucosal dissection (ESD) for EGC. Clinical features and endoscopic characteristics of EGC such as location, histological differentiation, longest diameter, tumor morphology, mucosal break, converging fold, color change, and surface irregularity were reviewed. Histological ulceration was defined based on ESD specimens. Results A total of 633 EGC lesions from 613 patients were included and histological ulcerations were found in 90 lesions (14.2%). Presence of converging folds, tumor morphology, and color changes on endoscopic examination were related to histological ulceration in the univariate analysis and converging folds along with color changes were statistically significant factors in the multivariate analysis. Kaplan–Meier analysis showed that patients with histological ulcerations in EGCs tended to have higher marginal recurrence rates. Conclusions Mucosal breaks are not equivalent to histological ulcerations. Rather, the existence of converging folds and color changes during endoscopic examination suggest histological ulcerations. Endoscopists should consider these factors when they decide the treatment modality for EGCs.

The area of endoscopic application has been continuously expanded since its introduction in the last century and the frequency of its use also increased stiffly in the last decades. Because gastrointestinal endoscopy is naturally exposed to diseased internal organs and contact with pathogenic materials, endoscopy mediated infection or disease transmission becomes a major concern in this field. Gastrointestinal endoscopy is not for single use and the proper reprocessing process is a critical factor for safe and reliable endoscopy procedures. What needed in these circumstances is a practical guideline for reprocessing the endoscope and its accessories which is feasible in the real clinical field to guarantee acceptable prevention of pathogen transmission. This guideline contains principles and instructions of the reprocessing procedure according to the step by step. And it newly includes general information and updated knowledge about endoscopy-mediated infection and disinfection. Multiple societies and working groups participated to revise; Korean Association for the Study of the Liver, the Korean Society of Infectious Diseases, Korean College of Helicobacter and Upper Gastrointestinal Research, the Korean Society of Gastroenterology, Korean Society of Gastrointestinal Cancer, Korean Association for the Study of Intestinal Diseases, Korean Pancreatobiliary Association, the Korean Society of Gastrointestinal Endoscopy Nurses and Associates and Korean Society of Gastrointestinal Endoscopy. Through this cooperation, we enhanced communication and established a better concordance. We still need more researches in this field and fill up the unproven area. And our guidelines will be renewed accordingly.

Background/Aims: The rate of nonneoplastic pathology (NNP) after endoscopic resection (ER) of gastric epithelial neoplasia (GEN) has been reported to be 3%–7%. However, to date, the associations of pretreatment characteristics with NNP have not been identified. The aim of this study was to develop a predictive model for NNP after ER. Methods: Among 817 patients who underwent ER for GEN, factors associated with NNP were identified by univariate and multivariate analyses. Weighted points considering the β coefficient were allocated to each variable that was significant in the multivariate analysis. The predictive score was calculated by the total points. The area under the receiver operating characteristic curve (AUROC) was calculated for the predictive score. Results: The rate of NNP was 8.8%. After multivariate analysis, poor demarcation from the background, no ulceration, a flat appearance, and low-grade dysplasia were significant factors predictive of NNP. One point each was allocated for no ulcer, flat appearance, and low-grade dysplasia. Two points were allocated for poor demarcation from the background. The predictive score ranged from 0 to 5 points. Patients were categorized as being at low risk (0, 1, or 2 points) or high risk (3, 4, or 5 points) for NNP. The AUROC was 0.82 (95% confidence interval, 0.77 to 0.88; p

BackgroundBismuth quadruple therapy (BQT) is recommended as empirical first-line therapy because it is not affected by antibiotic resistance. We examined whether past exposure to metronidazole affected BQT outcomes.MethodsThe records of seven hospitals were searched for patients who received BQT for Helicobacter pylori eradication between 2009 and 2020. The association between past metronidazole exposure and the eradication rate was evaluated.ResultsThis study was a multicenter retrospective study. Around 37,602 people tested for H. pylori infection were identified, and 7,233 received BQT. About 2,802 (38.7%) underwent a 13C-urea breath test to confirm eradication. The BQT efficacy was 86.4% among patients without metronidazole exposure and 72.8% among patients with exposure (p

Aortoduodenal fistula is a rare but life-threatening condition that can cause gastrointestinal bleeding. Due to its rarity, it is often overlooked as a cause of gastrointestinal blood loss. Notably, the mortality rate of aortoduodenal fistula is nearly 100% in undiagnosed and untreated cases. We report a case of aortoduodenal fistula, which resulted in the patient’s death. This report highlights the importance of considering even extremely rare causes of gastrointestinal bleeding in the differential diagnosis in patients with such a presentation.

Background/AimsAlthough acid suppressants are widely used for the prevention or treatment of drug-induced upper gastrointestinal bleeding (GIB), evidence regarding the prevention of anticoagulant-related GIB is scarce. The aim of this study was to evaluate the protective effect of acid suppressants against anticoagulant-related GIB.Methods : A systematic review was conducted of studies that evaluated the protective effect of acid suppressants against anticoagulant-related GIB found in PubMed, the Cochrane library, Embase, and KoreaMed from the date of database inception to April 2018. Random effect model meta-analyses with sensitivity analyses were conducted. The methodological quality of each included publication was evaluated using the Risk of Bias Assessment Tool for Nonrandomized Studies. Publication bias was assessed.Results : In total, six nested case-control or cohort studies were identified and analyzed. Proton-pump inhibitors (PPI) had a protective effect against upper GIB in patients on dicumarinics (risk ratio [RR], 0.56; 95% confidence interval [CI], 0.38 to 0.83; I2, 0%); however, the histamine-2 receptor antagonist did not have the same effect (RR, 0.97; 95% CI, 0.52 to 1.81; I2, 0%). Acid suppressants did not have a protective effect against GIB in patients on dabigatran (hazard ratio, 0.78; 95% CI, 0.44 to 1.37; I2, 81.8%).Conclusion : sThe protective effect of PPIs against dicumarinics-related upper GIB was clear, while there was no evidence supporting the protective effect of acid suppressants against dabigatran-related GIB. However, in the absence of randomized trials demonstrating a lack of bias, solid conclusions cannot be drawn.

Background/Aims The risk of peritoneal seeding following perforation after endoscopic resection in patients with early gastric cancer is unclear. The purpose of this study was to investigate long-term clinical outcomes including peritoneal seeding and overall survival rate following gastric perforation during endoscopic submucosal dissection (ESD). Methods : Between January 2002 and March 2015, 556 patients were diagnosed with early gastric cancer and underwent ESD. Among them, 34 patients (6.1%) experienced gastric perforation during ESD. Clinicopathological data of these patients were reviewed to determine the clinical outcome and evidence of peritoneal seeding. Results : Among 34 patients with perforation, macroperforations occurred during ESD in 17 cases (50%), and microperforation was identified in the remaining 17 cases (50%). All patients except one who underwent emergency surgery due to severe panperitonitis were managed successfully by endoscopic clipping (n=27) or conservative medical treatment (n=6). No evidence of peritoneal seeding after perforation associated with ESD was found in our cohort. Cumulative survival rates did not differ between the perforation and non-perforation groups (p=0.691). Furthermore, mortality was not associated with perforation. In addition, multivariate analysis showed that tumor size and achievement of curative resection were related to cancer recurrence. Perforation was not associated with cancer recurrence and survival. Conclusion : s Perforation associated with ESD does not lead to worse clinical outcomes such as peritoneal seeding or cumulative survival rate. Therefore, periodic follow-up might be possible if curative resection was achieved even if perforation occurred during ESD.

It is essential to maintain high-quality endoscopy given the increasing number of endoscopic screens performed in Korea. The training of fellows to perform endoscopies is challenging. The rapid development of endoscopic techniques and rising patient complexity increase the training pressures. At the end of training, all practitioners must perform endoscopy safely and effectively. Here, we examine the current status of endoscopy training in Korea. Although our system produces many competent endoscopists, there is room for improvement. Formal training programs should be developed to train the trainers. Specific assessment tools measuring performance and improving training are required. Changes should be made at all levels to improve our endoscopy training system.

In this paper, we propose a symmetric series convolutional neural network (SS-CNN), which is a novel deep convolutional neural network (DCNN)-based super-resolution (SR) technique for ultrasound medical imaging. The proposed model comprises two parts: a feature extraction network (FEN) and an up-sampling layer. In the FEN, the low-resolution (LR) counterpart of the ultrasound image passes through a symmetric series of two different DCNNs. The low-level feature maps obtained from the subsequent layers of both DCNNs are concatenated in a feed forward manner, aiding in robust feature extraction to ensure high reconstruction quality. Subsequently, the final concatenated features serve as an input map to the latter 2D convolutional layers, where the textural information of the input image is connected via skip connections. The second part of the proposed model is a sub-pixel convolutional (SPC) layer, which up-samples the output of the FEN by multiplying it with a multi-dimensional kernel followed by a periodic shuffling operation to reconstruct a high-quality SR ultrasound image. We validate the performance of the SS-CNN with publicly available ultrasound image datasets. Experimental results show that the proposed model achieves a high-quality reconstruction of the ultrasound image over the conventional methods in terms of peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM), while providing compelling SR reconstruction time.

Peptic ulcer bleeding (PUB) is the most common cause of non-variceal upper gastrointestinal bleeding, and its frequency has been declining over the past decades. However, mortality from PUB persists, and it is still a serious challenge in clinical practice. Although endoscopic intervention is the basic treatment modality for PUB, pharmacological therapy is an important adjunct. The emergence of proton pump inhibitors (PPIs) enables maintenance of intragastric pH ＞6, which greatly helps in the treatment of PUB. Continuous intravenous infusion of high-dose PPI reduces the re-bleeding rate, thereby helping avoid additional surgery in patients with high-risk stigmata. Moreover, administration of PPIs prior to endoscopy may reduce the need for additional endoscopic intervention. Recently introduced gastric acid suppressants, such as potassium-competitive acid blockers, have shown promising results in further treatment of PUB.

Accurate diagnosis of Helicobacter pylori (H. pylori) infection is mandatory for the effective management of many gastroduodenal diseases. Currently, various diagnostic methods are available for detecting these infections, and the choice of method should take into account the clinical condition, accessibility, advantage, disadvantage, as well as cost-effectiveness. The diagnostic methods are divided into invasive (endoscopic-based) and non-invasive methods. Non-invasive methods included urea breath test, stool antigen test, serology, and molecular methods. Invasive methods included endoscopic imaging, rapid urease test, histology, culture, and molecular methods. In this article, we provide a review of the currently available options and recent advances of various diagnostic methods.

Background/Aims Dual priming oligonucleotide-based multiplex polymerase chain reaction (DPO-based PCR) can detect the presence of clarithromycin resistance without culture. The aim of this study was to investigate the cost-effectiveness of DPO-based PCR for Helicobacter pylori eradication. Methods : From 2015 to 2016, medical records of patients who received H. pylori eradication therapy were analyzed. Patients were divided into two groups: tailored group patients who were treated based on DPO-based PCR and empirical group patients. Eradication rate and medical cost, including diagnostic tests, eradication regimens, and 13C-urea breath tests, were compared between the two groups. Cost for one successful eradication was calculated in each group. The expected cost of eradication for empirical treatment was investigated by varying the treatment duration and eradication rate. Results : A total of 527 patients were analyzed (tailored group 208, empirical group 319). The eradication success rate of the first-line therapy was higher in the tailored group compared to that in the empirical group (91.8% vs 72.1%, p

Antithrombotic agents are used increasingly in Asia. The management of patients on antithrombotics undergoing elective or emergency endoscopy has become an increasing clinical challenge for gastroenterologists. Current practice guidelines have been developed by societies from western countries. On the other hand, these guidelines cannot meet the specific needs of the Asian Pacific region, raising the need for separate guidelines in Asia. This review compares the recommendations of previous guidelines with the most recently published Asian guidelines regarding the management of patients on antithrombotic agents undergoing elective and emergency endoscopy.

Background/Aims Rebleeding is associated with mortality in patients with peptic ulcer bleeding (PUB), and risk stratification is important for the management of these patients. The purpose of our study was to examine the risk factors associated with rebleeding in patients with PUB. Methods : The Korean Peptic Ulcer Bleeding registry is a large prospectively collected database of patients with PUB who were hospitalized between 2014 and 2015 at 28 medical centers in Korea. We examined the basic characteristics and clinical outcomes of patients in this registry. Univariate and multivariate analyses were performed to identify the factors associated with rebleeding. Results : In total, 904 patients with PUB were registered, and 897 patients were analyzed. Rebleeding occurred in 7.1% of the patients (64), and the 30-day mortality was 1.0% (nine patients). According to the multivariate analysis, the risk factors for rebleeding were the presence of co-morbidities, use of multiple drugs, albumin levels, and hematemesis/hematochezia as initial presentations. Conclusion : s The presence of co-morbidities, use of multiple drugs, albumin levels, and initial presentations with hematemesis/hematochezia can be indicators of rebleeding in patients with PUB. The wide use of proton pump inhibitors and prompt endoscopic interventions may explain the low incidence of rebleeding and low mortality rates in Korea.

Background/Aims: In Korea, increasing clarithromycin resistance has led to the need for an alternative first-line therapy for the eradication of Helicobacter pylori (H. pylori) infection. Concomitant therapy (CT) and sequential therapy (ST) have been proposed as alternative regimens. The aim of this study was to compare the eradication rate from using CT and ST in Korea. Methods : A literature review was performed on studies comparing the efficacy of CT and ST in Korea. Data were pooled to obtain the odds ratio (OR) of the eradication rate with 95% confidence intervals (CIs). The eradication rates were considered both on an intention-to-treat (ITT) and a per-protocol (PP) bases. Results : Six studies provided data on 1,897 Korean adult patients. The pooled OR was 1.382 (95% CI: 1.031-1.853, p=0.031) for ITT analysis and 2.114 (95% CI: 1.502-2.974, p

Background/AimsThe aim of this study was to investigate the effects of rebamipide on tight junction proteins in the esophageal mucosa in a rat model of gastroesophageal reflux disease (GERD).Methods : GERD was created in rats by tying the proximal stomach. The rats were divided into a control group, a proton pump inhibitor (PPI) group, and a PPI plus rebamipide (PPI+R) group. Pantoprazole (5 mg/kg) was administered intraperitoneally to the PPI and PPI+R groups. An additional dose of rebamipide (100 mg/kg) was administered orally to the PPI+R group. Mucosal erosions, epithelial thickness, and leukocyte infiltration into the esophageal mucosa were measured in isolated esophagi 14 days after the procedure. A Western blot analysis was conducted to measure the expression of claudin-1, -3, and -4.Results : The mean surface area of mucosal erosions, epithelial thickness, and leukocyte infiltration were lower in the PPI group and the PPI+R group than in the control group. Western blot analysis revealed that the expression of claudin-3 and -4 was significantly higher in the PPI+R group than in the control group.Conclusion : sRebamipide may exert an additive effect in combination with PPI to modify the tight junction proteins of the esophageal mucosa in a rat model of GERD. This treatment might be associated with the relief of GERD symptoms.

Gastric adenoma (dysplasia) is a precancerous lesion. Therefore, managements of gastric adenomas are important for preventing the development of gastric cancers and for detecting gastric cancers at earlier stages. The Vienna classification divides gastric adenomas into two categories: high-grade dysplasia and low-grade dysplasia. Generally, endoscopic resection is performed for adenoma with high-grade dysplasia due to the coexistence of carcinoma and the potential of progression to carcinomas. However, the treatments of adenoma with low-grade dysplasia remain controversial. Currently two treatment strategies for the low-grade type have been suggested; First is the ‘wait and see’ strategy; Second is endoscopic treatment (e.g., endoscopic mucosal resection, endoscopic submucosal dissection, or argon plasma coagulation). In this review, we discuss the current optimal strategies for endoscopic management of gastric adenoma.

Sporadic non-ampullary duodenal adenoma is uncommon and found incidentally during endoscopic examinations. Brunner’s gland hyperplasia is commonly encountered during endoscopic examinations. Adenomas arising from Brunner’s gland hyperplasia originate from the glandular cells, and the surface epithelia are usually intact. Little has been reported on adenomas originating from the surface epithelium that overrides Brunner’s gland hyperplasia. Here, we report a case of a sporadic non-ampullary duodenal adenoma overriding the cystic dilatation of Brunner’s gland hyperplasia.

Background/Aims Early gastric cancer (EGC) with ulcerations can be treated via endoscopic resection (ER) when it is differentiated pathologically, limited to the mucosa, and

Gastrointestinal endoscopy is important in diagnosis, treatment, and prevention of many diseases of the digestive tract. The ability to perform esophagogastroduodenoscopy (EGD) safely, effectively, and efficiently has become the mainstay of gastroenterology practice. In Korea, EGD education is usually imparted as a component of gastroenterology training programs during fellowship. In this review, we discuss the general principles of EGD training. Formal curriculum development with devising clear goals and effective training methods should be developed in the future.

The Korean Society of Gastrointestinal Endoscopy (KSGE) issued guidelines for endoscope reprocessing for the first time in 1995, and the version of the guidelines was updated in August 2009, August 2012, and March 2015. Guidelines for endoscope reprocessing should be revised continuously, because new disinfectants and devices are developed and introduced. The current official version of the KSGE guidelines for endoscope reprocessing is explained herein to assist the reader in understanding the KSGE requirements for cleaning and disinfecting endoscopes.