Search

Abstract Colon polyp detection and removal via colonoscopy are essential for colorectal cancer screening and prevention. This study aimed to develop a colon polyp detection program based on the RetinaNet algorithm and verify its clinical utility. To develop the AI-assisted program, the dataset was fully anonymized and divided into 10 folds for 10-fold cross-validation. Each fold consisted of 9,639 training images and 1,070 validation images. Video data from 56 patients were used for model training, and transfer learning was performed using the developed still image-based model. The final model was developed as a real-time polyp-detection program for endoscopy. To evaluate the model’s performance, a prospective randomized controlled trial was conducted at six institutions to compare the polyp detection rates (PDR). A total of 805 patients were included. The group that utilized the AI model showed significantly higher PDR and adenoma detection rate (ADR) than the group that underwent colonoscopy without AI assistance. Multivariate analysis revealed an OR of 1.50 for cases where polyps were detected. The AI-assisted polyp-detection program is clinically beneficial for detecting polyps during colonoscopy. By utilizing this AI-assisted program, clinicians can improve adenoma detection rates, ultimately leading to enhanced cancer prevention.

Background/Aims: A quick and accurate diagnosis of Helicobacter pylori (H. pylori) infections is vital for effectively managing many upper gastrointestinal tract diseases. Many diagnostic methods have been developed for rapid and accurate diagnosis, including invasive and non-invasive methods, but each tool has some limitations. Among the invasive diagnostic methods, the rapid urease test (RUT) is a relatively time-saving and accurate method, but a variation in the reaction time range causes inconvenience and inefficiency in the clinical field. This study developed a liquid-type medium, Helicotest®, to enable faster detection. This study examined the reaction time of a new liquid-type RUT kit with other commercial kits. Methods: Two H. pylori strains were cultured (H. pylori ATCC 700392 and 43504), and the urease activity of H. pylori was measured using a urease activity assay kit (MAK120, Sigma Aldrich). Four RUT kits were used to compare the time of H. pylori detection, including Helicotest® (Won Medical, Bucheon, Korea), Hp kit (Chong Kun Dang, Seoul, Korea), CLO kit (Halyard, Alpharetta, GA, USA), and ASAN Helicobacter Test® (ASAN, Seoul, Korea). Results: The detection of H. pylori was possible in bacterial amounts less than 10 μL. The color change was detected from five minutes with bacterial densities of 5 μL and 10 μL for both strains, whereas 30 minutes and one hour were required for 0.5 μL and a 1 μL bacterial density of ATCC 43504 and 700392 strains, respectively. Conclusions: Compared to other RUT kits, Helicotest® showed the fastest reaction. Therefore, faster diagnosis in clinical practice is expected.

Background/Aims: Rapid and accurate diagnostic tools are essential for the timely recognition of Helicobacter pylori (H. pylori) in clinical practice. The rapid urease test (RUT) is a comparatively accurate and time-saving method recommended as a first-line diagnostic test. The primary objective of conducting the RUT is to obtain rapid results, thus enabling the initiation of an eradication therapy based on clarithromycin resistance testing. This study aimed to assess the reaction time and accuracy of a new liquid-type RUT. Method: In this prospective study, consecutive dyspeptic or check-up patients referred to our clinic for endoscopy were assessed to evaluate the rapidity and accuracy of a novel liquid-type RUT (Helicotest®, WON Medical, Bucheon, Republic of Korea) compared with another commercial RUT kit (HP kit, Chong Kun Dang, Seoul, Republic of Korea) and a real-time quantitative PCR-based assay (Seeplex® H.pylori-ClaR Detection, Seegene, Republic of Korea). RUTs were analyzed at 10 min, 30 min, 60 min, and 120 min. Results: Among the 177 enrolled patients, 38.6% were infected with H. pylori. The positivity rates of the liquid-type RUT were 26.1, 35.8, 39.2%, and 41.5% at 10, 30, 60, and 120 min, respectively. When compared with the HP kit test, the time needed to confirm positivity was significantly reduced by 28.6 min (95% CI, 16.60–39.73, p < 0.0001). Helicotest® had a greater accuracy (96.02 ± 1.47), sensitivity (98.53 ± 1.46) and NPV (99.03 ± 0.97) compared to the HP kit. Conclusions: Compared to the commonly used RUT, the new liquid-type RUT presented faster and reliable results. Such findings could improve H. pylori treatment outcomes, particularly in outpatient clinical settings.

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.

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.

This study aimed to develop a convolutional neural network (CNN) using the EfficientNet algorithm for the automated classification of acute appendicitis, acute diverticulitis, and normal appendix and to evaluate its diagnostic performance. We retrospectively enrolled 715 patients who underwent contrast-enhanced abdominopelvic computed tomography (CT). Of these, 246 patients had acute appendicitis, 254 had acute diverticulitis, and 215 had normal appendix. Training, validation, and test data were obtained from 4,078 CT images (1,959 acute appendicitis, 823 acute diverticulitis, and 1,296 normal appendix cases) using both single and serial (RGB [red, green, blue]) image methods. We augmented the training dataset to avoid training disturbances caused by unbalanced CT datasets. For classification of the normal appendix, the RGB serial image method showed a slightly higher sensitivity (89.66 vs. 87.89%; p = 0.244), accuracy (93.62% vs. 92.35%), and specificity (95.47% vs. 94.43%) than did the single image method. For the classification of acute diverticulitis, the RGB serial image method also yielded a slightly higher sensitivity (83.35 vs. 80.44%; p = 0.019), accuracy (93.48% vs. 92.15%), and specificity (96.04% vs. 95.12%) than the single image method. Moreover, the mean areas under the receiver operating characteristic curve (AUCs) were significantly higher for acute appendicitis (0.951 vs. 0.937; p < 0.0001), acute diverticulitis (0.972 vs. 0.963; p = 0.0025), and normal appendix (0.979 vs. 0.972; p = 0.0101) with the RGB serial image method than those obtained by the single method for each condition. Thus, acute appendicitis, acute diverticulitis, and normal appendix could be accurately distinguished on CT images by our model, particularly when using the RGB serial image method.

Objectives Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant vascular disorder characterized by recurrent epistaxis, telangiectasia, and visceral arteriovenous malformations (AVMs). Activin A receptor-like type 1 (ACVRL1/ALK1) and endoglin (ENG) are the principal genes whose mutations cause HHT. No multicenter study has yet investigated correlations between genetic variations and clinical outcomes in Korean HHT patients. Methods Seventy-two members from 40 families suspected to have HHT based on symptoms were genetically screened for pathogenic variants of ACVRL1 and ENG. Patients with genetically diagnosed HHT were also evaluated. Results In the HHT genetic screening, 42 patients from 24 of the 40 families had genetic variants that met the pathogenic criteria (pathogenic very strong, pathogenic strong, pathogenic moderate, or pathogenic supporting) based on the American College of Medical Genetics and Genomics Standards and Guidelines for either ENG or ACVRL1: 26 from 12 families (50%) for ENG, and 16 from 12 families (50%) for ACVRL1. Diagnostic screening of 42 genetically positive HHT patients based on the Curaçao criteria revealed that 24 patients (57%) were classified as having definite HHT, 17 (41%) as having probable HHT, and 1 (2%) as unlikely to have HHT. Epistaxis was the most common clinical presentation (38/42, 90%), followed by visceral AVMs (24/42, 57%) and telangiectasia (21/42, 50%). Five patients (12%) did not have a family history of HHT clinical symptoms. Conclusion Only approximately half of patients with ACVRL1 or ENG genetic variants could be clinically diagnosed as having definite HHT, suggesting that genetic screening is important to confirm the diagnosis.

Abstract While colorectal cancer is known to occur in the gastrointestinal tract. It is the third most common form of cancer of 27 major types of cancer in South Korea and worldwide. Colorectal polyps are known to increase the potential of developing colorectal cancer. Detected polyps need to be resected to reduce the risk of developing cancer. This research improved the performance of polyp classification through the fine-tuning of Network-in-Network (NIN) after applying a pre-trained model of the ImageNet database. Random shuffling is performed 20 times on 1000 colonoscopy images. Each set of data are divided into 800 images of training data and 200 images of test data. An accuracy evaluation is performed on 200 images of test data in 20 experiments. Three compared methods were constructed from AlexNet by transferring the weights trained by three different state-of-the-art databases. A normal AlexNet based method without transfer learning was also compared. The accuracy of the proposed method was higher in statistical significance than the accuracy of four other state-of-the-art methods, and showed an 18.9% improvement over the normal AlexNet based method. The area under the curve was approximately 0.930 ± 0.020, and the recall rate was 0.929 ± 0.029. An automatic algorithm can assist endoscopists in identifying polyps that are adenomatous by considering a high recall rate and accuracy. This system can enable the timely resection of polyps at an early stage.

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.

The role of Helicobacter pylori (H. pylori) eradication in patients undergoing gastrectomy for gastric cancer is unclear. Although European and Asian guidelines strongly recommend H. pylori eradication in patients who undergo endoscopic resection for early gastric cancer, these guidelines do not specify the tests useful for diagnosing H. pylori infection, the optimal timing and appropriate eradication regimens, and follow-up strategies in patients undergoing gastrectomy for gastric cancer. This review aims to update the guidelines for the diagnosis and management of H. pylori infection in patients undergoing gastrectomy for gastric cancer. We have focused on the following issues: 1) diagnostic tests for H. pylori infection in the remnant stomach, 2) optimal timing and regimen for H. pylori eradication, and 3) role of H. pylori eradication in reducing the risk of metachronous gastric cancer in the remnant stomach.

Kaposi’s sarcoma (KS) is a multicentric human immunodeficiency virus-associated neoplasm characterized by multiple vascular nodules in the skin, mucous membranes, and viscera. Gastrointestinal acquired immunodeficiency syndrome (AIDS)-related KS is the most common visceral involvement reported in disseminated disease. Here, we present the findings of a rare case of KS involving multiple organs with abdominal pain and active bleeding in the colon. Multiple intraluminal lesions were found in the terminal ileum, sigmoid colon, and rectum by ileocolonoscopy, and in the jejunum and ileum by fluoroscopy. Abdominopelvic CT revealed multiple enhanced flat lesions in the ileum and enlarged lymph nodes. The diagnosis was confirmed by histopathology, and antiretroviral therapy was initiated as the treatment of choice for KS. Owing to the increasing number of AIDS patients, it is essential for radiologists and clinicians to be aware of the imaging characteristics of KS to protect physicians from indiscriminate exposure to AIDS.

Background/Aims Frequent bleeding after endoscopic resection (ER) has been reported in patients with end-stage renal disease (ESRD). We aimed to evaluate the association and clinical significance of bleeding with ER in ESRD patients on dialysis. Methods Between February 2008 and December 2018, 7,571 patients, including 47 ESRD patients on dialysis who underwent ER for gastric neoplasia, were enrolled. A total of 47 ESRD patients on dialysis were propensity score-matched 1:10 to 470 non-ESRD patients, to adjust for between-group differences in variables such as age, sex, comorbidities, anticoagulation use, tumor characteristics, and ER method. Matching was performed using an optimal matching algorithm. For the matched data, clustered comparisons were performed using the generalized estimating equation method. Medical records were retrospectively reviewed. Frequency and outcomes of post-ER bleeding were evaluated. Results Bleeding was more frequent in the ESRD with dialysis group than in the non-ESRD group. ESRD with dialysis conferred a significant risk of post-ER bleeding (odds ratio, 6.1; 95% confidence interval, 2.7–13.6; p

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.

Abstract Background The majority of colonic obstructions result from colorectal cancer. However, malignancies of extra-colonic origin can also disrupt colorectal patency, and the efficacy of self-expanding metal stents (SEMS) insertion as a bridge to surgery in these patients are still in debate. The aim of this study is to evaluate the efficacy of endoscopic stenting as a bridge to surgery (BTS) for extra-colonic malignancy (ECM)-induced colonic obstruction. Methods Thirty-three patients with colonic obstruction due to ECM who received self-expanding metal stents (SEMS) insertion at a single academic tertiary medical center between 2004 and 2015 were included. The purpose of SEMS insertion was determined based on whether the patient’s medical records indicated any surgical plans before SEMS insertion. Technical success was defined as a patent SEMS covering the entire length of the obstruction. Bridging success was defined as elective surgical procedures after the first SEMS insertion. Results Among the 33 patients who underwent SEMS insertion for colorectal obstruction due to ECM, nine underwent SEMS as a BTS. Technical success was achieved in 100% (9/9). Seven patients underwent elective surgery after successful decompression with the first SEMS, and the bridging success rate was 77.8% (7/9). Two patients needed secondary stent insertion before elective surgery. However, none of them required emergent surgery. No major complications occurred, including death related to colorectal endoscopic procedures, perforation, or bleeding. Conclusion SEMS insertion as a BTS is a good treatment option to avoid emergent surgery in patients with colonic obstruction caused by extra-colonic malignancy.

Background/Aims Although proton pump inhibitors (PPIs) remain a mainstay for the suppression of gastric acid secretion, long-term PPI use is associated with side effects. However, the genotoxicity associated with long-term PPI use is unclear. Materials and Methods This prospective observational pilot study enrolled patients who had been on PPIs for >1 year and healthy controls from July 2015 to August 2016. The subjects completed self-report questionnaires pertaining to their drug and medical history, and only those with no medical history and a ≥2-year wash-out period (for drugs other than PPIs) were included. We collected peripheral-blood lymphocytes from long-term PPI users and healthy controls and analyzed the genotoxicity by using the cytokinesis-block micronucleus cytome assay; we also determined the fasting serum levels of pyridoxine, folate, cobalamin, and homocysteine. Results Ten long-term PPI users and 40 healthy control subjects were enrolled. The median serum pyridoxine, folate, cobalamin, and homocysteine levels were not significantly different between the groups. The median frequencies of micronuclei (MNi), nucleoplasmic bridges (NPBs), and nuclear buds (Nbuds) per 1,000 binucleated cells, in long-term PPI users and healthy controls, were 30.3 and 16.3 (P

Background/Aims There is limited data to compare the clinical characteristics and recurrence rates between left-sided primary epiploic appendagitis (PEA) versus left-sided acute colonic diverticulitis (ACD), and right-sided PEA versus right-sided ACD, respectively. Methods We retrospectively reviewed the medical records and radiologic images of the patients who presented with left-sided or right-sided acute abdominal pain and had computer tomography performed at the time of presentation showing radiological signs of PEA or ACD between January 2004 and December 2014. We compared the clinical characteristics of left PEA versus left ACD and right PEA versus right ACD, respectively. Results Fifty-six patients (left:right = 27:29) and 308 patients (left:right = 24:284) were diagnosed with symptomatic PEA and ACD, respectively. Left-sided PEA were statistically significantly younger (50.2 ± 15.4 years vs. 62.1 ± 15.8 years, P= 0.009), more obese (body mass index [BMI]: 26.3 ± 2.9 kg/m2 vs. 22.3 ± 3.1 kg/m2 , P< 0.001), and had more tendencies with normal or mildly elevated high-sensitivity C-reactive protein (hsCRP) (1.2 ± 1.3 mg/dL vs. 8.4 ± 7.9 mg/dL, P< 0.001) than patients with left-sided ACD. The discriminative function of age, BMI and CRP between left-sided PEA versus left-sided ACD was 0.71 (cutoff: age ≤ 59 years, sensitivity of 66.7%, specificity of 77.8%), 0.84 (cutoff: BMI > 24.5 kg/m2 , sensitivity of 80.0%, specificity of 80.0%) and 0.80 (cutoff: CRP < 1.8 mg/dL, sensitivity of 72.2%, specificity of 85.7%). Conclusions If patients with left lower quadrant abdominal pain are less than 60 years, obese (BMI > 24.5 kg/m2 ) with or without normal to mild elevated CRP levels (CRP < 1.8 mg/dL), it might be necessary for clinicians to suspect the diagnosis of PEA rather than ACD.

In laparoscopic surgery for colorectal and gastric cancer, it is difficult to locate the tumor in the cavity for excision. Tumors in the colon or stomach are blocked by mucous membranes; thus, the view from the cavity is obscured. Therefore, to determine the location of the tumor, a marker can be installed around the tumor and the location of the tumor can be found using a sensor. Until now, most of the clip-detectors that have been developed can detect the location of tumors for either colorectal or gastric cancer. The research on the development of a detector that can detect the location of tumors for both colorectal and gastric cancer, is insufficient. Most detectors for tumor location determination are devised using a magnet by connecting a wire to a clip. In this method, the position of the magnet moves along the length of the wire. Therefore, it is difficult for the detector to detect the exact location of the tumor. Based on this method, this study designs a clip maker to determine the location of a tumor and a detector that can detect the clip. The clip and the sensing element are directly connected. The clip is developed using ferrite and coil to generate a magnetic field induced by an eddy current in the metal (clip), and the detector is designed using the Colpitts oscillator to induce a magnetic field. After installing the prepared clip at the tumor location, the detector is used to detect the clip, and accordingly, the location of the tumor can be identified using the detector. To test the performance of the clip and detector, we conducted animal experiments. In the course of the animal experiment, four clips were installed in the colon and stomach, and we succeeded in detecting all the clips. Because the clip-detector is used to locate the tumor during laparoscopic surgery, an endoscope must be used. Therefore, it is predicted that the demand for laparoscopic surgery and endoscopic medical industry will increase because of the clip-detector.

During laparoscopic surgery for colorectal or gastric cancers, locating the tumor for excision is difficult owing to it being obscured by mucous membranes. Therefore, a clip can be installed around the tumor, which can be located using a sensor. Most of the clip–detectors developed thus far can only detect tumors in either the colon or stomach and require a wire to connect the clip and detector. This study designs a clip and detector that can locate a tumor in the stomach and colon. The clip contains a neodymium magnet that generates a magnetic field, and the detector includes a Colpitts oscillator that allows magnetic coupling of the clip and detector. After installing the prepared clip at the tumor location, the detector is used to locate the clip. To test the clip and detector, we conducted animal experiments, during which four clips were installed in the colon and stomach of a mini pig. We succeeded in locating the clips within 2.17 and 3.14 s in the stomach and colon, respectively, which were shorter than the detection times reported in previous studies. The demand for laparoscopic surgery and endoscopes is predicted to increase owing to this method.

Background: Anemia is a common extraintestinal manifestation of inflammatory bowel disease (IBD). However, data on the influence of anti-tumor necrosis factor-alpha (anti-TNF-α) agents and iron supplementation on anemia in patients with IBD are sparse. We assessed the effect of iron supplementation in patients with IBD initially treated with an anti-TNF-α agent. Methods: Data from 79 IBD patients who started anti-TNF-α treatment at a tertiary hospital were analyzed. The patients were divided into the anti-TNF-α ( n = 52) and anti-TNF-α with iron supplementation ( n = 27) groups. Effects on laboratory parameters, the prevalence of anemia, and disease activity were evaluated at baseline (year 0) and 1 year later. Results: The hemoglobin (Hb) level significantly increased between years 0 and 1 in both groups [12.0 ± 1.8–13.3 ± 2.0 g/dL in the anti-TNF-α group ( p

Background/Aims: Although some previous studies reported that a treatment combined with mucoprotective agent could improve the eradication rate in dual or triple therapy, there are other reports that question the efficacy of combining these drugs in concomitant therapy (CoCTx). The aim of this study was to investigate the effects of rebamipide or ecabet on the Helicobacter pylori (H. pylori) eradication combined with CoCTx. Methods: We retrospectively reviewed the medical records of 277 patients with proven H. pylori infection. They were assigned to one of 3 regimens for 10 days, twice daily: (a) CoCTx (n=118): lansoprazole 30 mg, amoxicillin 1 g, metronidazole 500 mg, and clarithromycin 500 mg; (b) CoCTx+rebamipide (100 mg) (n=85); (c) CoCTx+ecabet (1 g) (n=74). Results: The baseline characteristics were not significantly different. H. pylori eradication rates were 82.2% (97/118) in CoCTx, 90.6% (77/85) in CoCTx+rebamipide, and 89.2% (66/74) in CoCTx+ecabet (p=0.17), which were statistically insignificant. Overall adverse events were more frequently reported in the CoCTx+rebamipide (50.6%. 43/85) and CoCTx+ecabet (44.6%, 33/74) groups than in the CoCTx (32.2%, 38/118) (p = 0.03) group. Drug compliances were not different between three groups (CoCTx: 95.8%, 113/118; CoCT+rebamipide: 92.9%, 79/85; CoCTx+ecabet 98.6%,73/74) (p=0.209). Multivariate analysis showed that the risk of eradication failure was significantly increased with decreased drug compliance (odds ratio 3.52, 95% confidence interval 1.00-12.32; p=0.05). Conclusions: Addition of these mucoprotective agent was not superior to CoCTx alone for eradicating H. pylori infection with frequent adverse events. Rather, drug compliance is the most related factor affecting the eradication rate. Our data suggest the importance of drug compliance over the drugs used.

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.

Strongyloides stercoralis is endemic to tropical and subtropical regions, and infections are usually asymptomatic. However, immunocompromised patients, such as those receiving immunosuppressive therapy, high-dose steroids, or chemotherapy, can develop fatal hyperinfections. An 84-year-old man without any symptoms was diagnosed with strongyloidiasis during a regular screening colonoscopy. His medical history only involved a gastric endoscopic submucosal dissection for early gastric cancer 6 months previously. Few cases have been published about asymptomatic strongyloidiasis diagnosed in an immunocompetent host via endoscopic mucosal resection with characteristic colonoscopic findings. We report a case of colon-involved asymptomatic strongyloidiasis with specific colonic findings of yellowish-white nodules. This finding may be an important marker of S. stercoralis infection, which could prevent hyperinfections.

Sensors in the medical field to detect specific tissues, such as radars, must provide accurate signals from frequency generators. In order to supply an accurate frequency signal, the oscillator must have a low phase noise. Therefore, the resonator used in the oscillator must provide a high QL. Therefore, in this paper, we have proposed a low-phase-noise X-band oscillator that used a resonator with a high value of QL as a sensor for tissue-locating applications. The resonator had a split-ring structure and consisted of an open-loaded, T-type stub with a high-QL; such high-QL levels were enabled by controlling the length of the open-circuit in the T-type stub. This led to the generation of only low-phase noise in the proposed oscillator. Experimental results showed that, at an operating frequency of 10.08 GHz, the output power was 18.66 dBm, the second harmonic suppression was −34.40 dBc, and the phase noise was −138.13 dBc/Hz at an offset of 100 kHz. This proposed oscillator can be used as a sensor to detect the location of tissues during laparoscopic surgery.

Background: Increased prevalence of antibiotic resistance to Helicobacter pylori (H. pylori) infection worldwide has driven the search for a new therapeutic candidate. Recently, sitafloxacin, a novel 4-quinolone agent, has emerged as a new therapeutic option for H. pylori eradication, in Japan. However, data on its efficacy for H. pylori eradication in Korea are limited. Therefore, we aimed to investigate the therapeutic potential of sitafloxacin as a first-line treatment for patients with Helicobacter infection through gastric tissue culture-based studies. Materials and Methods: We prospectively enrolled treatment-naïve patients with H. pylori infection who visited the Gil Medical Center between March 2015 and March 2018. After obtaining written informed consent from patients, a total of 121 H. pylori strains were collected. We tested the susceptibility of these strains to sitafloxacin, and other antibiotics for Helicobacter eradication, including clarithromycin (CLR), metronidazole (MTZ), amoxicillin (AMX), tetracycline (TET), levofloxacin (LEV), and ciprofloxacin (CIP) using the agar dilution technique. The minimum inhibitory concentration (MIC) of these antibiotics against H. pylori strains were determined. Results: None of the H. pylori strains obtained were resistant to sitafloxacin (MIC > 1, n = 0), while other conventional eradication drugs including CLR, MTZ, AMX, and TET showed 24.8% (n = 30), 30.6% (n = 37), 5.0% (n = 6), and 0.8% (n = 1) resistance, respectively. Compared to the resistance rates of other quinolones (LEV [36.4%, n = 44] and CIP [37.2%, n = 45]), sitafloxacin showed the best antibiotic performance against Helicobacter strains (0%, n = 0). Furthermore, sitafloxacin also inhibited the growth of 14 H. pylori strains (12.4%), which were resistant to both of clarithromycin, and metronidazole, and 27 strains (22.3%) with multidrug resistance. Conclusions: Sitafloxacin might be a new promising candidate for Helicobacter eradication where antibiotic resistance for Helicobacter is an emerging medical burden, such as in Korea.

Oral 5-aminosalicylic acid agents (mesalazine and sulfasalazine) and azathioprine are the mainstays of treatment for inflammatory bowel disease. Reports of pulmonary toxicity induced by oral 5-aminosalicylic acid agents or azathioprine in patients with inflammatory bowel disease are very rare; to date, only 38 cases have been reported worldwide. We, herein, report a case involving a 26-year-old man who was diagnosed with eosinophilic pneumonia after using mesalazine and azathioprine for the treatment of Crohn's disease and recovered after treatment. We also found that the fraction of exhaled nitric oxide level was elevated in this patient. After treatment, the fraction of exhaled nitric oxide level decreased and the symptoms improved. The present case shows that fraction of exhaled nitric oxide is related to the disease activity and treatment effectiveness of druginduced eosinophilic pneumonia.

Background/AimsThe increased resistance of Helicobacter pylori to antibiotics has increased the need to develop new treatments for this bacterium. The aim of our study was to identify new drugs with anti-H. pylori activity.Methods : We screened a small molecule library—the library of pharmacologically active compounds (LOPAC), which includes 1,280 pharmacologically active compounds—to identify inhibitors of H. pylori growth. The minimal inhibitory concentrations (MICs) of antibiotics against multidrug-resistant H. pylori strains were determined using the agar dilution method.Results : We identified diphenyleneiodonium (DPI) as a novel anti-H. pylori agent. The MIC values for DPI were

Background/AimsThe use of laparoscopic adjustable gastric banding (LAGB) is increasing proportionally with the obesity epidemic. However, some postoperative complications have been highlighted as major problems associated with LAGB. There is no consensus concerning the endoscopic management of these adverse events. The aim of this study was to retrospectively review the feasibility and effectiveness of endoscopic treatment for LAGB complications.Methods : We retrospectively evaluated 352 patients who underwent LAGB between 2011 and 2015. LAGB-associated complications developed in 26 patients (7.4%). This study involved six patients (1.7%) who received endoscopic treatment.Results : Types of LAGB-induced complications in our series included intragastric migration (n=3), gastric leaks (n=2), and gastric fistulas (n=1). The endoscopic treatment of these complications was successful in four of the six patients. Endoscopic band removal was successful in two patients. All gastric leaks were successfully closed via an endoscopic procedure. In two cases (intragastric migration and gastric fistula), endoscopic treatment was not sufficient, and surgery was performed.Conclusion : sEndoscopic procedures afforded acceptable treatment of band migration and gastric leaks after LAGB. However, the results were poor in patients with gastric fistula.

Background/AimsMicroRNAs (miRNAs) regulate gene expression. We assess miRNA regulation by Helicobacter pylori infection and elucidate their role in H. pylori-infected gastric epithelial cells.Methods : The relationship between miRNA expression and DNA methylation was examined. Cells were treated with the nuclear factor-kappaB (NF-κB) inhibitor Bay 11-7082 to determine the relationship between miRNA expression and NF-κB signal transduction.Results : In the negative control cells infected with H. pylori 26695, the expression of six miRNAs was increased, whereas the expression of five miRNAs was decreased. The expression of upregulated miRNAs was increased when the host cells were treated with H. pylori and an NF-κB inhibitor. miR-127-5p, -155, and -181 were associated with increased interleukin 6 (IL-6) secretion in H. pylori infected cells treated with anti-miRNA. The expression of miR-155, -127-5p, -195, -216, -206, and -488 increased by approximately 3-fold following treatment with the methylation inhibitor Aza.Conclusion : sWe found novel miR-NAs in H. pylori-infected negative control cells using miRNA microarrays. Upregulated miRNA expression was inversely related to the transcription of NF-κB. miR-195 and miR-488 appear to play a pivotal role in controlling IL-6 activity in H. pylori infection. miRNA expression in H. pylori infection was affected by methylation.

Background/Aims: Gastric cancer (GC), the third-leading cause of cancer death in the world, is typically diagnosed only in its advanced stages. WNT signaling has been associated with clinicopathological characteristics in diverse cancer types. But the systematic analysis of WNT5A, a member in the signaling, has not been inspected. Thus, our study used a meta-analysis to statistically associate WNT5A expression with GC clinicopathological characteristics. Methods: For a systematic literature review of GC in combination with the WNT signaling molecule WNT5A, we searched for PubMed, Cochrane Library, and Web of Science. It led to the five cohorts, in four eligible studies, consisting of 1,034 patients (617 WNT5A-positive and 417 WNT5A-negative patients). These patients were inspected by the library “meta” in R software for our meta-analysis. Results: Our meta-analysis, revealed a statistically significant associations of WNT5A-positivity with lymph node metastasis (p=0.0047), some types of Lauren diffuse subtype GCs (p

Background/Aim. In Korea, the rate of Helicobacter pylori (H. pylori) eradication has declined steadily as a result of increasing resistance to antibiotics, especially dual resistance to clarithromycin and metronidazole. However, microbiological culture data on drug-resistant H. pylori is lacking. This study evaluated the antimicrobial efficacy of candidate antibiotics against resistant H. pylori strains. Methods. After retrospectively reviewing the data from the Helicobacter Registry in Gil Medical Center (GMC) and Asan Medical Center (AMC), along with 4 reference strains, we selected the 31 single- or multidrug-resistant strains. The susceptibility of the H. pylori strains to seven antibiotics (clarithromycin, metronidazole, levofloxacin, amoxicillin, tetracycline, rifabutin, and furazolidone) and minimum inhibitory concentration were tested using the broth microdilution technique. Results. Among 31 antibiotic resistance strains for H. pylori, there were no strains resistant to rifabutin or furazolidone, which had MICs of

BACKGROUND:Watson for oncology (WFO) is a cognitive computing system providing decision support. We evaluated the concordance rates between the treatment options determined by WFO and those determined by a multidisciplinary team (MDT). METHODS:We reviewed the medical charts of patients diagnosed with colorectal cancer who visited the MDT at a single tertiary medical center from November 2016 to April 2017. WFO classified the treatment options for specific patients into three categories: 'Recommended', 'For consideration', and 'Not recommended'. Concordance rates between the WFO- and MDT-determined chemotherapy options, and the factors that potentially influence the concordance rate, were analyzed. RESULTS:Sixty-nine patients with colorectal cancer met with the MDT from Nov. 2016 to Feb. 2017. The mean age of the patients was 62 years (range: 34-86 years), and more patients were male (47/69) than female. Of the 69 patients, 51 (73.9%) were diagnosed with colon cancer, of whom 46.4% received the same regimen recommendation from WFO ('Recommended') as they did from the MDT. After inclusion of the 'For consideration' category from WFO, the concordance rate increased to 87.0%. The concordance rate between MDT and NCCN guidelines was 97.1%, and that between the WFO and NCCN guidelines was 88.4%. The concordance rates between WFO and MDT were significantly lower in patients with stage II, IIIC, or IV disease (P

Accurate prediction of lymph node status is of crucial importance in the appropriate treatment planning for patients with early gastric cancer (EGC). Some studies have examined factors predicting lymph node metastasis (LNM) in EGC; however, these studies did not consider sex-specific differences. This study aimed to investigate sex-specific differences in predictive risk factors of LNM in EGC based on surgical specimens. Patients who underwent surgical treatment for EGC between January 2003 and February 2016 were retrospectively evaluated. Patients who underwent previous gastric surgery or treatment for gastric neoplasms were excluded. Finally, 1076 patients treated for EGC were included in the analysis. We analyzed risk factors of LNM by dividing patients into male and female groups. Of 1076 patients (mean age 59.6 years), 69% were men. The overall LNM rate was 9.4%. The LNM rate was lower in men (7.8%) than in women (12.9%). Multivariate analysis showed that elevated type (odds ratio [OR], 2.084; 95% confidence interval [CI]: 1.053-4.125; P = 0.035), submucosal invasion (OR, 2.162; 95% CI: 1.018-4.595; P = 0.045), undifferentiated type (OR, 2.044; 95% CI: 1.107-3.772; P = 0.022), and lymphovascular invasion (LVI) (OR, 7.210; 95% CI: 3.835-13.554; P

Backgrounds/Aims. Watson for Oncology (WFO) is a cognitive technology that processes medical information by analyzing the latest evidence and guidelines. However, studies of the concordance rate between WFO and clinicians for advanced gastric cancer (AGC) are lacking. Methods. We retrospectively reviewed 65 patients with AGC who consulted WFO and the Gachon Gil Medical Center multidisciplinary team (GMDT) in 2016 and 2017. The recommendations of WFO were compared with the opinions of the GMDT. WFO provided three treatment options: recommended (first treatment option), for consideration (second treatment option), and not recommended. Results. In total, 65 patients (mean age 61.0 years; 44 males and 21 females) were included in the study. The concordance rate between WFO and the GMDT was 41.5% (27/65) at the recommended level and 87.7% (57/65) at the for consideration level. The main causes of discordance between WFO and the GMDT were as follows. First, WFO did not consider the medical history. Second, WFO recommended the use of agents that are considered outdated in Korea. Third, some patients wanted to be involved in a clinical trial. Fourth, some patients refused to use the biologic agents recommended by WFO for financial reasons as they were not covered by medical insurance. Conclusions. The concordance rate at the recommended level was relatively low but was higher at the for consideration level. Discordances arose mainly from the different medical circumstances at the Gachon Gil Medical Center (GMC) and the Memorial Sloan Kettering Cancer Center (MSKCC), the main WFO consulting center. The utility of WFO as a tool for supporting clinical decision making could be further improved by incorporating regional guidelines.

Isolated mediastinal tuberculous lymphadenitis is clinically rare. Its clinical presentation may mimic an esophageal submucosal tumor by extrinsic compression. A 26-year-old woman was referred to our hospital for an esophageal subepithelial tumor. A 15×10 mm sized subepithelial lesion was found 30 cm from the upper incisors on esophagogastroduodenoscopy. We diagnosed the lesion as a submucosal tumor, and performed endoscopic ultrasonography-guided fine needle aspiration for a pathologic diagnosis. The histologic examination revealed granulomatous inflammation consistent with tuberculosis. We suggest that the use of endoscopic ultrasonography and fine needle aspiration may be helpful in making an early diagnosis and planning for an optimal treatment. (Korean J Gastroenterol 2016;68:312-316)

A 34-year-old man was referred to our hospital with gastric polypoid lesions and biopsy-confirmed neuroendocrine tumor (NET). Computed tomography (CT) revealed a 3×3.5×8-cm retroperitoneal mass behind the pancreas, with multiple hepatic metastases. His serum gastrin level was elevated to 1,396 pg/mL. We performed a wedge resection of the stomach, a right hemi-hepatectomy, and a retroperitoneal mass excision. After careful review of the clinical, radiological, histopathological, and immunohistochemical findings, peripancreatic gastrinoma, and synchronous gastric NET were ultimately diagnosed. We reviewed a CT scan that had been performed 6 years previously after surgery for a duodenal perforation. There was no evidence of gastric or hepatic lesions, but the retroperitoneal mass was present at the same site. Had gastrinoma been detected earlier, our patient could have been cured using less invasive treatment. This case demonstrates how important it is to consider Zollinger-Ellison syndrome in patients with a recurrent or aggressive ulcer.

Background/AimsRectal neuroendocrine tumors (NETs) are among the most common of gastrointestinal NETs. Due to recent advances in endoscopy, various methods of complete endoscopic resection have been introduced for small (≤10 mm) rectal NETs. However, there is a debate about the optimal treatment for rectal NETs. In our study, we aimed to evaluate the efficacy and feasibility of endoscopic resection using pneumoband and elastic band (ER-BL) for rectal NETs smaller than 10 mm in diameter.MethodsA total of 55 patients who were diagnosed with rectal NET from January 2004 to December 2011 at Gil Medical Center were analyzed retrospectively. Sixteen patients underwent ER-BL. For comparison, 39 patients underwent conventional endoscopic mucosal resection (EMR).ResultsThere was a markedly lower deep margin positive rate for ER-BL than for conventional EMR (6% [1/16] vs. 46% [18/39], P=0.029). Four patients who underwent conventional EMR experienced perforation or bleeding. However, they recovered within a few days. On the other hand, patients whounderwent endoscopic resection using a pneumoband did not experience any complications. In multivariate analysis, ER-BL (P=0.021) was independently associated with complete resection.ConclusionsER-BL is an effective endoscopic treatment with regards to deep margin resection for rectal NET smaller than 10 mm.

Background and Objectives: An effective flushing technique is essential to reduce intravenous (IV)-related complications and improve patient care. New technology should contribute to such improvements, while reducing costs and increasing care efficiency. This study evaluated the efficacy, safety, and convenience of a new flushing technique using a Baro Flush™ controller. Materials and Methods: We evaluated the efficacy and safety of Baro Flush™ by measuring the infusion flushing volume and pressure in vitro. Afterwards, we prospectively enrolled 3000 patients with flushing and assigned 1500 patients with a new technique for flushing and 1500 with a conventional flushing method, which was performed by 48 registered nurses (RNs) at the Gil Medical Center in June 2018. The efficacy, safety, and convenience of the new flushing method were evaluated though a questionnaire survey. Results: The average flushing pressure was 12.5 ± 0.6 psi (86.18 ± 4.14 kPa) with 1.2 ± 0.2 mL per flush, as recommended by the Centers for Disease Control and Prevention based on 85 experiments. No IV-catheter-related complications were reported by the RNs during the study. More than 80% of the RNs reported that the new flushing method was easier to learn, improved care efficacy, and was more convenient than conventional flushing. Conclusions: The new flushing method using a Baro Flush™ controller showed improved efficacy, safety, and convenience compared with the conventional flushing method, and no IV-catheter-related complications occurred, including occlusion and inflammation. The new flushing method promises to reduce IV-catheter-related complications and shows improved efficacy, safety, and convenience.

Antibiotic resistance is the major reason for Helicobacter pylori treatment failure, and the increasing frequency of antibiotic resistance is a challenge for clinicians. Resistance to clarithromycin and metronidazole is a particular problem. The standard triple therapy (proton pump inhibitor, amoxicillin, and clarithromycin) is no longer appropriate as the first-line treatment in most areas. Recent guidelines for the treatment of H. pylori infection recommend a quadruple regimen (bismuth or non-bismuth) as the first-line therapy. This treatment strategy is effective for areas with high resistance to clarithromycin or metronidazole, but the resistance rate inevitably increases as a result of prolonged therapy with multiple antibiotics. Novel potassium-competitive acid blocker-based therapy may be effective, but the data are limited. Tailored therapy based on antimicrobial susceptibility test results is ideal. This review discussed the current important regimens for H. pylori treatment and the optimum H. pylori eradication strategy.

Background and objective: Although obesity is associated with an increased risk of peptic ulcer disease (PUD), no study has evaluated the association of PUD with sarcopenia. The aim of this study was to evaluate the association of sarcopenia and obesity with PUD. Material and Methods: Data from the Korean National Health and Nutrition Examination Survey (KNHANES) IV and V for 2007−2012 were used. PUD history, dietary, alcohol consumption, smoking, physical activity patterns, and other socioeconomic factors were analyzed. Sarcopenia index (appendicular skeletal muscle mass (kg) ÷ body mass index (kg/m2)) and body fat mass were determined by dual-energy X-ray absorptiometry. Univariate and multivariate analyses were performed to evaluate the association of sarcopenia with the prevalence of PUD. Results: The 7092 patients were divided into the sarcopenic obesity (SO, n = 870), sarcopenic non-obesity (n = 2676), non-sarcopenic obesity (NSO, n = 2698), and non-sarcopenic non-obesity (NSNO, n = 848) groups. The prevalence of PUD in these groups was 70 (7.9%), 170 (7.4%), 169 (6.3%), and 47 (3.8%), respectively (p < 0.001). A crude analysis revealed that the prevalence of PUD was 2.2-fold higher in the SO group than in the NSNO group (odds ratio (OR), 2.2; 95% confidence interval (CI), 1.5−3.2), the significance of which remained after adjustment for age, sex, body mass index, and HOMA-IR (homeostatic model assessment insulin resistance) score (OR, 1.9; 95% CI, 1.3−2.7). Conclusion: In conclusion, in this nationally representative cohort, the combination of muscle and fat mass, as well as obesity, was associated with an increased risk of PUD.

Background/Aims Gastric cancer ranks fifth for incidence and fourth leading cause of mortality worldwide. Therefore, detecting gastric cancer in early stage is important for favourable disease outcome. In this study, we aimed to validate previously developed artificial intelligence (AI) computer-aided detection (CADe) algorithm, called ALPHAON and to compare outcome with previous studies present AI outperforming and assisting endoscopists of diverse levels of expertise in detecting gastric neoplasm. Methods We used the retrospective data of 500 still images, including 5 benign gastric ulcers and 95 with gastric cancer, and 400 normal images. Thereby we validated CADe algorithm in addition to comparing diagnostic performance status of 4 expert endoscopists, 4 trainees and 4 beginners from two university affiliated hospital with CADe algorithm. After a washing-out period of over 2 weeks, endoscopists perform gastric detection on the same dataset of the 500 endoscopic images again marked by ALPHAON. Results The CADe algorithm presented high validity on detecting gastric neoplasm with accuracy (0.88, 95% CI:0.85 to 0.91), sensitivity (0.93, 95% CI:0.88 to 0.98), specificity (0.87, 95% CI:0.84 to 0.90) and AUC (0.962). There were no significant differences between AI and expert (0.97, 95% CI:0.94 to 0.99, p=0.170) in sensitivity apart from trainee (0.85, 95% CI:0.81 to 0.89, p=0.003) and beginner (0.73, 95% CI:0.67 to 0.79, p<0.001). After a washing-out period of over 2 weeks, significant improvement was present especially in beginner group (accuracy 0.94 (0.93 to 0.96) p<0.001, sensitivity 0.87 (0.82 to 0.92) p<0.001, specificity 0.96 (0.95 to 0.97) p<0.001). Conclusion High validation performance state of CADe algorithm system, detecting gastric neoplasm was verified. Also, ALPHAON has demonstrated its potential to serve as endoscopic educator for beginner. Prospective validation in multicenter would be required before application of CADe in clinical field for delicate endoscopic screening. [ABSTRACT FROM AUTHOR]

Stomach cancer has a high annual mortality rate worldwide necessitating early detection and accurate treatment. Even experienced specialists can make erroneous judgments based on several factors. Artificial intelligence (AI) technologies are being developed rapidly to assist in this field. Here, we aimed to determine how AI technology is used in gastric cancer diagnosis and analyze how it helps patients and surgeons. Early detection and correct treatment of early gastric cancer (EGC) can greatly increase survival rates. To determine this, it is important to accurately determine the diagnosis and depth of the lesion and the presence or absence of metastasis to the lymph nodes, and suggest an appropriate treatment method. The deep learning algorithm, which has learned gastric lesion endoscopyimages, morphological characteristics, and patient clinical information, detects gastric lesions with high accuracy, sensitivity, and specificity, and predicts morphological characteristics. Through this, AI assists the judgment of specialists to help select the correct treatment method among endoscopic procedures and radical resections and helps to predict the resection margins of lesions. Additionally, AI technology has increased the diagnostic rate of both relatively inexperienced and skilled endoscopic diagnosticians. However, there were limitations in the data used for learning, such as the amount of quantitatively insufficient data, retrospective study design, single-center design, and cases of non-various lesions. Nevertheless, this assisted endoscopic diagnosis technology that incorporates deep learning technology is sufficiently practical and future-oriented and can play an important role in suggesting accurate treatment plans to surgeons for resection of lesions in the treatment of EGC. [ABSTRACT FROM AUTHOR]