Assessing risk stratification in long-term outcomes of rectal neuroendocrine tumors following endoscopic resection: a multicenter retrospective study.

OBJECTIVES: While endoscopic resection of rectal neuroendocrine tumors (NETs) has significantly increased, long-term data on risk factors for recurrence are still lacking. Our aim is to analyze the long-term outcomes of patients with rectal NETs after endoscopic resection through risk stratification. METHODS: In this multicenter retrospective study, we included patients who underwent endoscopic resection of rectal NETs from 2009 to 2018 and were followed for ≥12 months at five university hospitals. We classified the patients into three risk groups according to the clinicopathological status of the rectal neuroendocrine tumors: low, indeterminate, and high. The high-risk group was defined if the tumors have any of the followings: size ≥ 10 mm, lymphovascular invasion, muscularis propria or deeper invasion, positive resection margins, or mitotic count ≥2/10. RESULTS: A total of 346 patients were included, with 144 (41.6%), 121 (35.0%), and 81 (23.4%) classified into the low-, indeterminate-, and high-risk groups, respectively. Among the high-risk group, seven patients (8.6%) received salvage treatment 28 (27-67) days after the initial endoscopic resection, with no reported extracolonic recurrence. Throughout the follow-up period, 1.1% (4/346) of patients experienced extracolonic recurrences at 56.5 (54-73) months after the initial endoscopic resection. Three of these patients (75%) were in the high-risk group and did not undergo salvage treatment. The risk of extracolonic recurrence was significantly higher in the high-risk group compared to the other groups (p = 0.039). CONCLUSION: Physicians should be concerned about the possibility of metastasis during long-term follow-up of high-risk patients and consider salvage treatment.

Deep learning in negative small-bowel capsule endoscopy improves small-bowel lesion detection and diagnostic yield.

OBJECTIVES: Although several studies have shown the usefulness of artificial intelligence to identify abnormalities in small-bowel capsule endoscopy (SBCE) images, few studies have proven its actual clinical usefulness. Thus, the aim of this study was to examine whether meaningful findings could be obtained when negative SBCE videos were reanalyzed with a deep convolutional neural network (CNN) model. METHODS: Clinical data of patients who received SBCE for suspected small-bowel bleeding at two academic hospitals between February 2018 and July 2020 were retrospectively collected. All SBCE videos read as negative were reanalyzed with the CNN algorithm developed in our previous study. Meaningful findings such as angioectasias and ulcers were finally decided after reviewing CNN-selected images by two gastroenterologists. RESULTS: Among 202 SBCE videos, 103 (51.0%) were read as negative by humans. Meaningful findings were detected in 63 (61.2%) of these 103 videos after reanalyzing them with the CNN model. There were 79 red spots or angioectasias in 40 videos and 66 erosions or ulcers in 35 videos. After reanalysis, the diagnosis was changed for 10 (10.3%) patients who had initially negative SBCE results. During a mean follow-up of 16.5 months, rebleeding occurred in 19 (18.4%) patients. The rebleeding rate was 23.6% (13/55) for patients with meaningful findings and 16.1% (5/31) for patients without meaningful findings (P = 0.411). CONCLUSION: Our CNN algorithm detected meaningful findings in negative SBCE videos that were missed by humans. The use of deep CNN for SBCE image reading is expected to compensate for human error.

Association between regular physical activity and lower incidence of colorectal cancer in patients with diabetes mellitus: a nationwide cohort study.

AIM: The aim of this work was to investigate the association between changes in physical activity (PA) status and the development of colorectal cancer (CRC) in patients with diabetes. METHOD: This nationwide population study included 1 439 152 patients with diabetes who underwent a health screening provided by the Korean National Health Insurance Service between January 2009 and December 2012 and a follow-up screening after 2 years. Based on changes in PA status, participants were categorized into four groups: remained inactive, remained active, active-to-inactive and inactive-to-active. RESULTS: During the median follow-up period of 5.2 years, 38 244 new cases of CRC were diagnosed. Compared with the remained inactive group, among the three other groups, the remained active group had the lowest risk of CRC [adjusted hazard ratio (aHR) 0.93; 95% CI 0.90-0.96], followed by the inactive-to-active group (aHR 0.97; 95% CI 0.94-1.00) and active-to-inactive group (aHR 0.99; 95% CI 0.96-1.02), after adjusting for confounding variables (p = 0.0007). This reduction in cancer incidence in the remained active group was observed for both rectal cancer (aHR 0.87, 95% CI 0.79-0.95) and colon cancer (aHR 0.93, 95% CI 0.90-0.97), irrespective of sex. In terms of the intensity and amount of PA, moderate intensity PA was the most effective, and a positive correlation was found between the amount of PA and the reduction in CRC incidence. CONCLUSION: Regular PA was independently associated with a decreased risk of CRC in patients with diabetes. The intensity and amount of physical activity both play a role in reducing the risk.

Five-year Progress of Gastric MALT Lymphoma Presenting as Gastric Outlet Obstruction.

This paper reports a 70-year-old female with gastric extranodal marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (gastric MALT lymphoma) as a rare case of gastric outlet obstruction. Five years earlier, she initially presented with weight loss and anemia. Esophagogastroduodenoscopy (EGD) revealed multiple gastric and duodenal ulcers with a pyloric deformity, while histology revealed chronic active inflammation and a Helicobacter pylori (H. pylori) infection. Three years earlier, she underwent EGD per the National Cancer Screening Program and was diagnosed with antral and duodenal ulcers. A forceps biopsy specimen from one of the ulcers showed the findings of gastric MALT lymphoma, but she did not visit the hospital for proper management. She visited complaining of a loss of appetite. EGD revealed a gastric outlet obstruction (GOO) caused by antral deformity and pyloric narrowing. A staged workup with CT and PET revealed full-layered, encircling antral wall thickening and several enlarged mesenteric lymph nodes. She was finally diagnosed with a gastric MALT lymphoma at Ann Arbor stage I1E with translocation t(11;18). She was treated with palliative surgery for GOO and systemic chemotherapy with a CHOP regimen. This paper reports a gastric MALT lymphoma that progressed from superficial mucosal lesions to an overt mass with regional lymph node metastasis for five years.

Quantitative multiplex real-time polymerase chain reaction assay for the detection of Helicobacter pylori and clarithromycin resistance.

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.

The pattern of metachronous recurrence after endoscopic submucosal dissection for gastric adenocarcinoma and dysplasias.

BACKGROUND/AIMS: Metachronous recurrence incidences and risk factors following endoscopic submucosal dissection (ESD) for gastric adenocarcinoma and dysplasias were investigated. METHODS: Retrospective review of electronic medical records of patients who underwent gastric ESD at The Catholic University of Korea, Yeouido St. Mary's Hospital. RESULTS: A total of 190 subjects were enrolled for analysis during the study period. The mean age was 64.4 years-old and the male sex occupied 73.7%. The mean observation period following ESD was 3.45 years. The annual incidence rate of metachronous gastric neoplasms (MGN) was about 3.96%. The annual incidence rate was 5.36% for the low-grade dysplasia group, 6.47% for the high-grade dysplasia group, and 2.74% for the EGC group. MGN was more frequent in the dysplasia group than in the EGC group (p<0.05). For those with MGN development, the mean time interval from ESD to MGN was 4.1 (±1.8) years. By using the Kaplan-Meier model, the estimated mean MGN free survival time was 9.97 years (95% confidence interval, 8.53-11.40) The histological types of MGN were not related to the primary histology types. CONCLUSION: MGN following ESD developed in 3.96% annually and MGN was more frequent in the dysplasia group. The histological types of MGN did not correlate with those of primary neoplasm.

The benefit of the bismuth add-on to the 2-week clarithromycin-based triple regimen for Helicobacter pylori eradication: a propensity score-matched retrospective study.

BACKGROUND: Bismuth salt is bacteriostatic and bactericidal against Helicobacter pylori (H. pylori). Little is known about the benefit of bismuth itself. Recently in Korea, government regulation changed to allow bismuth add-on to conventional triple eradication regimens. Study aimed the additional benefit of the bismuth add-on to the 2-week clarithromycin-based triple regimen for H. pylori eradication. METHODS: A single-centered retrospective review of electronic medical records was conducted in Seoul, Korea. Treatment-naïve H. pylori infected subjects treated with the clarithromycin-based triple regimen were consecutively enrolled. After propensity score matching, 118 subjects who were treated with rabeprazole 20 mg, amoxicillin 1 g, and clarithromycin 500 mg twice daily for 14 days (PAC) and matched 118 subjects with PAC plus bismuth subcitrate potassium 300 mg twice daily for 14 days (PACB) were included in the final analysis. The primary endpoint was the eradication success rates in each group.Article title: Kindly check and confirm the edit made in the article title.Yes, I agree with the article title.  RESULTS: The eradication success rates were 91.5% (86.4-96.6%) for PACB regimen and 81.4% (74.2-88.5%) for PAC in the intention-to-treat analysis, and 97.3% (94.2-100%) for PACB and 88.1% (81.9-94.3%) for PAC in the per-protocol analysis. The relative risk of eradication failure for PACB over PAC was calculated as 0.184 (0.0492-0688, p value = 0.005) in multiple regression logistic analysis. Compliance and adverse event incidence were not different between the two groups.Author names: Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 1 Given name: [Da Wit], Last name: [Shin]. Author 2 Given name: [Dae Young], Last name: [Cheung]. Author 3 Given name: [Ji Hee], Last name: [Song]. Author 4 Given name: [Fan Hee], Last name: [Lee]. Author 5 Given name: [Jin Il], Last name: [Kim]. Yes. I found the names presented are accurate and in the correct sequence. Author 1 Given name: [Da Wit], Last name: [Shin].Author 2 Given name: [Dae Young], Last name: [Cheung].Author 3 Given name: [Ji Hee], Last name: [Song].Author 6 Given name: [Han Hee], Last name: [Lee].Author 7 Given name: [Jin Il], Last name: [Kim]. CONCLUSION: The bismuth add-on to the 2-week clarithromycin-based triple regimen increased the eradication success rate.

[Clinical Impact Assessment and Utilization Prospects of the t(11:18) Chromosomal Translocation in Gastric MALT Lymphoma in Koreans: A Single Center Retrospective Analysis].

Background/Aims: The gastric extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (gastric MALT lymphoma) are mostly related to Helicobacter pylori infections. However, chromosomal aberration involving translocation t(11;18) is also frequently reported in these patients. Methods: The study was a retrospective review and analysis of electronic medical records to assess the factors which affect complete remission (CR) in patients with gastric MALT lymphoma. Based on the medical records, subjects with gastric MALT lymphoma were enrolled consecutively from January 2004 to December 2021. Results: Among the 77 subjects who were found with gastric MALT lymphoma in the database, 65 cases with complete records were analyzed. Of these, 66.2% (43/65) were H. pylori positive. Genetic analyses for t(11:18) were done on 41 subjects. The t(11:18) chromosomal translocation with MALT1:BIRC3 fusion was found in 31.7% (13/41) of the subjects. With H. pylori eradication therapy, 75% (21/28) of the subjects without t(11:18) achieved CR. However, only 23.1% (3/13) subjects with t(11:18) could achieve CR (p-value= 0.009). In the H. pylori-positive group, 85.7% (18/21) subjects without t(11:18) achieved CR with eradication therapy, but 71.4% (5/7) subjects with t(11:18) failed to achieve CR (p-value=0.004). In the H. pylori-negative group, 42.3% (3/7) of the subjects without t(11:18) achieved CR with eradication therapy. However, 83.3% (5/6) of H. pylori-negative subjects with t(11:18) failed to achieve CR with eradication therapy and needed additional radiotherapy (p-value=0.396). Conclusions: H. pylori negativity and the presence of t(11:18) were both risk factors for failure to achieve CR with H. pylori eradication therapy as the first line of treatment.

Factors associated with the risk of colorectal neoplasia in young adults under age 40.

BACKGROUND/AIMS: Recent epidemiologic studies have shown a continued increase in colorectal cancer incidence among younger adults. Little is known about the factors that contribute to the development of young-onset colorectal neoplasia (CRN). METHODS: A cross-sectional analysis was performed for individuals younger than 40 years who underwent colonoscopy in Seoul St. Mary's Hospital and its affiliated health screening center. High-risk CRN was defined as adenoma or sessile serrated lesion ≥ 10 mm, with three or more adenomas, villous histology, high grade dysplasia, or carcinoma. RESULTS: Of these 13,621 included participants, 2,023 (14.9%) had one and more CRN. Young patients with CRN tended to be elderly, male, obese, smoker, having a habit of drinking, and having comorbidities such as hypertension, dyslipidemia, diabetes, and chronic kidney disease. In a multivariate analysis adjusted for age, sex, obesity, smoking status, and alcohol intake, old age (odds ratio [OR], 1.086; 95% confidence interval [CI], 1.054 to 1.119), male sex (OR, 1.748; 95% CI, 1.247 to 2.451), obesity (OR, 1.439; 95% CI, 1.133 to 1.828), and smoking (OR, 1.654; 95% CI, 1.287 to 2.127) were independent risk factors for overall CRN. Obesity and smoking as two modifiable factors increased the risk for high-risk CRN even more than for overall CRN (OR, 1.734; 95% CI, 1.168 to 2.575 and OR, 1.797; 95% CI, 1.172 to 2.753, respectively). CONCLUSION: Obesity and smoking were modifiable risk factors for CRN in young adults. They increased the risk for highrisk CRN even more than for overall CRN. A colonoscopy might be beneficial for young individuals with these factors.

[Factors Associated with the Clinical Outcomes of Iatrogenic Colonic Perforation].

Background/Aims: This study evaluated the incidence of iatrogenic colonic perforation (ICP) in a high-volume center and analyzed the clinical outcomes and associated factors. Methods: As a retrospective study of the electronic medical records, the whole data of patients who underwent colonoscopy from June 2004 to May 2020 were reviewed. Results: During 16 years, 69,458 procedures were performed, of which 60,288 were diagnostic and 9,170 were therapeutic. ICP occurred in 0.027% (16/60,288) for diagnostic colonoscopies and in 0.076% (7/9,170) for therapeutic purposes (p=0.015; hazard ratio 2.878; 95% CI, 1.184-6.997). Fifty-two percent (12 cases) were managed with endoscopic clip closure, and 43.5% (10 cases) required surgery. The reasons for the procedure and the procedure timing appeared to affect the treatment decision. Perforations during therapeutic colonoscopy were treated with surgery more often than those for diagnostic purposes (66.7% [4/6] vs. 37.5% [6/16], p=0.221). Regarding the timing of the procedure, ICP that occurred in the afternoon session was more likely treated surgically (56.3% [9/16] vs. 0/5, p=0.027). Mortality occurred in two patients (2/23, 8.7%). Both were aged (mean age 84.0±1.4 vs. 65.7±10.5, p<0.001) and lately recognized (mean elapsed time [hours], 43.8±52.5 vs. 1.5±3.0, p<0.001) than the surviving patients. Conclusions: ICP occurs in less than 0.1% of cases. The events that occurred during the morning session were more likely managed endoscopically. Age over 80 years and a longer time before perforation recognition were associated with mortality.

The Influence of Past Metronidazole Exposure on the Outcome of Helicobacter pylori Eradication.

Background: Bismuth 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. Methods: The 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. Results: This 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 < 0.001). The eradication rate of BQT 14 days in patients with past exposure was higher than that of BQT <14 days (85.5 vs. 66.0%, p = 0.009). Multivariate analysis revealed that past metronidazole exposure [odds ratio (OR) 2.6, 95% CI 1.8-3.7; p < 0.001] and BQT <14 days (OR 1.5, 95% CI 1.2-2.0; p = 0.002) were independent risk factors for eradication failure. Conclusion: Past metronidazole exposure significantly lowered the BQT eradication rate. BQT 14 days should be recommended for patients with suspected metronidazole exposure.

Convolutional neural network-based object detection model to identify gastrointestinal stromal tumors in endoscopic ultrasound images.

BACKGROUND AND AIM: We aimed to develop a convolutional neural network (CNN)-based object detection model for the discrimination of gastric subepithelial tumors, such as gastrointestinal stromal tumors (GISTs), and leiomyomas, in endoscopic ultrasound (EUS) images. METHODS: We used 376 images from 114 patients with histologically confirmed gastric GIST or leiomyoma to train the EUS-CNN. We constructed the EUS-CNN using an EfficientNet CNN model for feature extraction and a weighted bi-directional feature pyramid network for object detection. We assessed the performance of our EUS-CNN by calculating its accuracy, sensitivity, specificity, and area under receiver operating characteristic curve (AUC) using a validation set of 170 images from 54 patients. Four EUS experts and 15 EUS trainees were asked to judge the same validation dataset, and the diagnostic yields were compared between the EUS-CNN and human assessments. RESULTS: In the per-image analysis, the sensitivity, specificity, accuracy, and AUC of our EUS-CNN were 95.6%, 82.1%, 91.2%, and 0.9234, respectively. In the per-patient analysis, the sensitivity, specificity, accuracy, and AUC for our object detection model were 100.0%, 85.7%, 96.3%, and 0.9929, respectively. The EUS-CNN outperformed human assessment in terms of accuracy, sensitivity, and negative predictive value. CONCLUSIONS: We developed the EUS-CNN system, which demonstrated high diagnostic ability for gastric GIST prediction. This EUS-CNN system can be helpful not only for less-experienced endoscopists but also for experienced ones. Additional EUS image accumulation and prospective studies are required alongside validation in a large multicenter trial.

Improved classification and localization approach to small bowel capsule endoscopy using convolutional neural network.

BACKGROUND: Although great advances in artificial intelligence for interpreting small bowel capsule endoscopy (SBCE) images have been made in recent years, its practical use is still limited. The aim of this study was to develop a more practical convolutional neural network (CNN) algorithm for the automatic detection of various small bowel lesions. METHODS: A total of 7556 images were collected for the training dataset from 526 SBCE videos. Abnormal images were classified into two categories: hemorrhagic lesions (red spot/angioectasia/active bleeding) and ulcerative lesions (erosion/ulcer/stricture). A CNN algorithm based on VGGNet was trained in two different ways: the combined model (hemorrhagic and ulcerative lesions trained separately) and the binary model (all abnormal images trained without discrimination). The detected lesions were visualized using a gradient class activation map (Grad-CAM). The two models were validated using 5,760 independent images taken at two other academic hospitals. RESULTS: Both the combined and binary models acquired high accuracy for lesion detection, and the difference between the two models was not significant (96.83% vs 96.62%, P = 0.122). However, the combined model showed higher sensitivity (97.61% vs 95.07%, P < 0.001) and higher accuracy for individual lesions from the hemorrhagic and ulcerative categories than the binary model. The combined model also revealed more accurate localization of the culprit area on images evaluated by the Grad-CAM. CONCLUSIONS: Diagnostic sensitivity and classification of small bowel lesions using a convolutional neural network are improved by the independent training for hemorrhagic and ulcerative lesions. Grad-CAM is highly effective in localizing the lesions.

Positive Fecal Occult Blood Test is a Predictive Factor for Gastrointestinal Bleeding after Capsule Endoscopy in Patients with Unexplained Iron Deficiency Anemia: A Korean Multicenter CAPENTRY Study.

BACKGROUND/AIMS: Capsule endoscopy (CE) is recommended as the primary method for the evaluation of unexplained anemia. This study aimed to assess the diagnostic yield of CE in patients with unexplained iron deficiency anemia (IDA) without overt bleeding, and to evaluate their long-term outcomes and related clinical factors. METHODS: Data of patients who underwent CE for the evaluation of IDA were reviewed from a CE registry in Korea. Additional clinical data were collected by the involved investigators of each hospital through a review of medical records. RESULTS: Among a total of 144 patients, the diagnostic yield of CE was 34%. Gastrointestinal (GI) bleeding was found in 6.3% (n=9) of the patients (occult bleeding in four patients and overt bleeding in five patients) during a mean follow-up of 17.8 months. Patients with a positive fecal occult blood test (FOBT) result at the initial diagnosis had a higher rate of GI bleeding after CE (p=0.004). In addition, a positive FOBT result was the only independent predictive factor for GI bleeding (hazard ratio, 5.30; 95% confidence interval, 1.41-19.85; p=0.013). CONCLUSION: Positive FOBT is a predictive factor for GI bleeding during follow-up after CE in patients with unexplained IDA without overt bleeding. Thus, patients with positive FOBT need to be more closely followed up.

Multidisciplinary and Multisociety Practice Guideline on Reprocessing Flexible Gastrointestinal Endoscopes and Endoscopic Accessories.

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.

Comparison of 7- and 14-Day Eradication Therapy for Helicobacter pylori with First- and Second-Line Regimen: Randomized Clinical Trial.

BACKGROUND: Although Helicobacter pylori is a key cause of gastric cancer development, its eradication rate has been decreasing by standard regimens. For successful eradication, duration of treatment has been issued for overcoming antibiotics resistance. We were to compare the eradication rate of 7-day vs. 14-day treatment in first- and second-line regimens. METHODS: This study was an open-label randomized controlled trial. A total of 369 H. pylori-infected patients were enrolled and assigned either to 7-day or 14-day proton pump inhibitor (PPI)-based standard triple therapy (STT; PPI-clarithromycin-amoxicillin). Bismuth-containing quadruple therapy was used as second-line therapy. Eradication success was defined as a negative 13C-urea breath test. RESULTS: In first-line treatment, eradication rate was 78.5% (106/135) and 78.6% (114/143) in the 7-day and 14-day treatment in per-protocol (PP) analysis (P = 0.805). In intention-to-treat (ITT) analysis, eradication rate was 64.0% (114/178) and 66.0% (126/191), respectively (P = 0.924). There was no significant difference in drug compliance (81.5% vs. 84.3%, P = 0.320). In second-line therapy, eradication rate was not significantly different in both treatments of PP analysis (91.7% [33/36] vs. 100% [45/45], P = 0.084). In the ITT analysis, eradication rate was 79.6% (35/44) and 90.4% (47/52), respectively (P = 0.080). Drug compliances were not significantly different between the two groups (95.5% vs. 98.1%, P = 0.728). CONCLUSION: PPI-based STT for H. pylori is not efficient as a first-line therapy both in 7 days and 14 days in Korea. Although bismuth-containing quadruple therapy for 14 days as a second line therapy tend to show higher eradication rate compared to 7-day therapy, this should be elucidated by further larger scaled studies. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02487511.

Risk factors for peritonitis in patients on continuous ambulatory peritoneal dialysis who undergo colonoscopy: a retrospective multicentre study.

BACKGROUND: Colonoscopy is associated with a risk of peritonitis in patients on peritoneal dialysis. However, no study has yet described the risk factors in play. METHODS: This was a retrospective multicentre study. The medical records of patients on continuous ambulatory peritoneal dialysis (CAPD) who underwent colonoscopy from January 2003 to December 2012 were analysed. We recorded demographic characteristics, colonoscopic factors, use of prophylactic antibiotics, and development of peritonitis. Colonoscopy-related peritonitis was defined as peritonitis developing within 1 week after colonoscopy. Demographic and clinical characteristics were compared between patients who did and those who did not develop peritonitis. RESULTS: During the study period, 236 patients on CAPD underwent colonoscopy, of whom 9 (3.8%) developed peritonitis. The rates of polypectomy/endoscopic mucosal resection were significantly higher in the peritonitis group than in the no peritonitis group (66.7 vs. 23.4%, p = 0.009). Prophylactic antibiotics were prescribed before colonoscopy in 65 patients; none developed peritonitis. No patient who developed peritonitis received prophylactic antibiotics (p = 0.067). CONCLUSIONS: Advanced procedures including polypectomy or endoscopic mucosal resection increase colonoscopy-related peritonitis in patients on CAPD. Randomized controlled trials to investigate whether prophylactic antibiotics are needed to prevent peritonitis in all CAPD patients are warranted.

Nationwide antibiotic resistance mapping of Helicobacter pylori in Korea: A prospective multicenter study.

INTRODUCTION: The eradication rates for Helicobacter pylori have decreased in Korea although the prevalence of this bacterium has also decreased. Antibiotic resistance is likely to be a crucial factor in H. pylori eradication success, and we therefore mapped these resistance patterns nationwide in Korea. MATERIALS AND METHODS: Five hundred and ninety adult subjects were prospectively enrolled from 2017 to 2018 from 15 centers across six geographic areas of Korea. A total of 580 biopsy tissues had been sampled from these patients during an upper endoscopy and were frozen at -80°C and delivered to a central laboratory. The agar dilution method was used to determine the minimum inhibitory concentration of amoxicillin, clarithromycin, metronidazole, tetracycline, ciprofloxacin, and levofloxacin for each H. pylori isolate. RESULTS: The culture success rate was 60.2% (349/580). Resistance rates against clarithromycin, metronidazole, amoxicillin, tetracycline, levofloxacin, and ciprofloxacin were 17.8%, 29.5%, 9.5%, 0%, 37.0%, and 37.0%, respectively. The geographic distribution of metronidazole and quinolone resistance was highly variable. Some subjects had multiple H. pylori strains in the antrum and body of the stomach and showed a heterogeneous resistance profile between these anatomic areas. The H. pylori multidrug resistance (MDR) rate was 25.2% (88/349) among amoxicillin, clarithromycin, metronidazole, tetracycline, and quinolone and 11.2% (39/349) among four of these major antibiotics except for quinolone. The Seoul and Chungcheong areas showed a relatively lower MDR rate. CONCLUSION: The antibiotic resistance of H. pylori differs by drug and geographic area in Korea. Detailed nationwide antibiotic resistance mapping is needed to develop an effective H. pylori eradication strategy.

A Case of Esophageal Squamous Cell Carcinoma in situ Arising from Esophageal Squamous Papilloma.

Squamous papilloma is a common benign tumor of the esophagus. Patients with papilloma are usually asymptomatic, and they are diagnosed incidentally during esophagogastroduodenoscopy. Most papillomas are small and easily removed by forceps biopsy. Recurrence of papilloma after removal is rare. Human papilloma virus infection is supposed to play a role in the development of esophageal papilloma; however, malignant transformation of papilloma is extremely unusual. Here, we report a case of malignant transformation of esophageal squamous papilloma at the gastroesophageal junction into squamous cell carcinoma in situ, which was treated by endoscopic submucosal dissection.