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.

Diagnostic Accuracy and Value of Magnetic Resonance Imaging–Ultrasound Fusion Transperineal Targeted and Template Systematic Prostate Biopsy Based on Bi-parametric Magnetic Resonance Imaging / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The purpose of this study was to investigate the diagnostic value of magnetic resonance imaging (MRI)–ultrasound (US) fusion transperineal targeted biopsy (FTB) and fusion template systematic biopsy (FSB) for prostate cancer (PCa) and clinically significant prostate cancer (csPCa) (intermediate/high grade [Gleason score ≥ 3+4]) based on bi-parametric MRI (bpMRI). @*Materials and methods@#Retrospectively, we analyzed 300 patients with elevated prostate-specific antigen (≥ 4.0 ng/mL) and/or abnormal findings in a digital rectal examination at the Korea University Hospital. All 300 men underwent bpMRI-US fusion transperineal FTB and FSB in the period from April 2017 to March 2019. @*Results@#PCas were detected in 158 of 300 men (52.7%), and the prevalence of csPCa was 34.0%. CsPCas were detected in 12 of 102 (11.8%) with Prostate Imaging-Reporting and Data System (PI-RADS) 3, 42 of 92 (45.7%) with PI-RADS 4, respectively; and 45 of 62 (72.6%) men with PI-RADS 5, respectively. BpMRI showed a sensitivity of 95.1% and negative predictive value of 89.6% for csPCa. FTB detected additional csPCa in 33 men (12.9%) compared to FSB. Compared to FTB, FSB detected additional csPCa in 10 men (3.9%). @*Conclusion@#BpMRI-US FTB and FSB improved detection of PCa and csPCa. The accuracy of bi-parametric MRI is comparable with that of multi-parametric MRI. Further, it is rapid, simpler, cheaper, and no side effects of contrast media. Therefore, it is expected that bpMRI-US transperineal FTB and FSB could be a good alternative to conventional US-guided transrectal biopsy, which is the current gold standard.

Updates on the Disinfection and Infection Control Process of the Accredited Endoscopy Unit

A thorough disinfection and infection control process associated with gastrointestinal endoscopy is highly important for the health and safety of the examinee and the medical staff involved in the procedure. Endoscopic reprocessing and disinfection are two of the most important steps in quality control of endoscopy. In 2019, the Korean Society of Gastrointestinal Endoscopy updated the Accreditation of Qualified Endoscopy Unit assessment items for these quality indicators. Assessment of disinfection and infection control comprises 28 mandatory items in the categories of disinfection education, pre-cleaning, cleaning, disinfection, rinsing, drying, reprocessing, storage, endoscopic accessories, water bottle and connectors, space/facilities, personal protective equipment, disinfection ledger, and regulations regarding infection control and disinfection. The updated Accreditation of Qualified Endoscopy Unit assessment items are useful for improving the quality of endoscopy by ensuring thorough inspection of endoscopic disinfection and infection control.

Adenocarcinoma of the Proximal Jejunum Misdiagnosed as Gastroparesis

The prevalence of small bowel cancer is relatively low. The abdominal pain that patients with small bowel cancer present as a symptom is non-specific and often interpreted as a normal finding on radiographic studies. To prevent delayed diagnosis of small bowel cancer, practitioners must maintain a certain level of suspicion. We report a case of delayed diagnosis of jejunal cancer as it was misdiagnosed as gastroparesis. A 69-year-old woman complained of recurrent nausea and vomiting. At the beginning of her hospitalization, we could not diagnose mechanical obstruction through esophagogastroduodenoscopy and abdominal computed tomography. A gastric emptying study revealed delayed gastric emptying. Although the patients received treatments, including administration of prokinetics and botulinum toxin injection, for gastroparesis, her symptoms aggravated. Subsequently, plain radiography of the abdomen revealed a double-bubble sign. Abdominal computed tomography was performed under the suspicion of small bowel obstruction; however, the diagnosis was not clear. Consequently, exploratory laparoscopy was performed. She underwent surgical management, including small bowel segmental resection and duodenojejunostomy, due to the jejunal mass with involvement of the stomach, pancreatic head, and mesentery of the transverse colon. The postoperative pathological results revealed a moderately differentiated adenocarcinoma of the jejunum.

Practice of Endoscopic Retrograde Cholangiopancreatography in Korea: Results from a National Survey / 대한췌담도학회지

BACKGROUND/AIMS: The aim of this study is to describe the outcome of the national survey and to determine the endoscopic retrograde cholangiopancreatography (ERCP) quality in Korea by comparing with the quality indicators. METHODS: We used the database of Health Insurance Review & Assessment Service and then performed anonymous national survey. RESULTS: Completed questionnaires were returned by 129 of 157 ERCP endoscopists. In Korea, annual ERCP rates have been consistently increased over years. Individual ERCP volume was high (>200 per year) in about half of ERCP endoscopists. Most ERCP endoscopists performed all of level I procedures. However, manometry, cholangiopancreatoscopy, and pancreatic procedures were performed mostly in institutions with high hospital volume. The rate of overall success was more than 90% in most ERCP endoscopists. However, the rate of precut sphincterotomy was high in more than a fourth of ERCP endoscopists. Twelve ERCP endoscopists experienced post-ERCP mortality within recent 1 year. ERCP training and radiation protection during ERCP did not meet the standard of quality indicators especially in institutions with low or moderate hospital volume. CONCLUSIONS: Technical issues during ERCP procedures in Korea fulfill the standard of quality indicators. However, a great effort is needed to improve issues about ERCP training and radiation protection.

Cogan Syndrome Accompanied with Meningitis / 대한평형의학회지

Cogan syndrome is a rare inflammatory disease characterized by intraocular inflammation and vestibulo-auditory dysfunction. The exact etiology of Cogan syndrome is still unknown, but is currently thought to be an autoimmune disease. Cogan syndrome can be accompanied with various conditions including fever, arthritis, skin rash, aortitis, central or peripheral nerve system involvement, lymphadenopathy, splenomegaly and diarrhea. We report a case of Cogan syndrome accompanied with meningitis.

Bone-forming peptide-2 derived from BMP-7 enhances osteoblast differentiation from multipotent bone marrow stromal cells and bone formation

Strategies for efficient osteogenic differentiation and bone formation from stem cells would have clinical applications in treating nonunion fracture healing. Many researchers have attempted to develop adjuvants as specific stimulators of bone formation for therapeutic use in patients with bone resorption. Therefore, development of specific stimulators of bone formation has therapeutic significance in the treatment of osteoporosis. To date, investigations of the mature forms of bone morphogenetic proteins (BMPs) have focused on regulation of bone generation. However, we previously identified new peptides from the immature precursor of BMP, and further analysis of these proteins should be performed. In this study, we identified a new peptide called bone-forming peptide-2 (BFP-2), which has stronger osteogenic differentiation-promoting activity than BMP-7. BFP-2 treatment of multipotent bone marrow stromal cells (BMSCs) induced expression of active alkaline phosphatase. In addition, BFP-2 enhanced CD44 and CD51 expression levels and increased Ca2+ content in BMSCs. Moreover, radiography at 8 weeks revealed that animals that had received transplants of BFP-2-treated BMSCs showed substantially increased bone formation compared with animals that had received BMSCs treated with BMP-7. Our findings indicate that BFP-2 may be useful in the development of adjuvant therapies for bone-related diseases.

Patient Monitoring and Associated Devices during Endoscopic Sedation / 대한소화기학회지

Sedation is an essential component for gastrointestinal endoscopy. It allows patients to tolerate unpleasant endoscopic procedures by relieving anxiety, discomfort, or pain. It also reduces patient's risk of physical injury during endoscopic procedures, while providing the endoscopist with an adequate setting for a detailed examination. For the safety during endoscopic sedation, patient monitoring is crucial. Minimal monitoring requirements during endoscopic sedation are periodic assessment of blood pressure and application of continuous pulse oximetry. Continuous electrocardiography is recommended in selected patients with high risk for sedation or have cardiopulmonary diseases. Continuous supplemental oxygen is also recommended for endoscopic sedation. This study describes detailed monitoring and associated devices based on the current guidelines and recommendations from gastrointestinal society of America, Europe, and Korea.

Delayed Cerebral Hyperperfusion Syndrome after Carotid Artery Stenting: the Finding of Multimodal MRI

A 78-year-old right handed man with hypertension presented with sudden onset dysarthria and right hemiparesis. Magnetic resonance angiography revealed near-occlusion of left proximal internal carotid artery. Emergent carotid stenting was performed. On the 17th day after carotid stenting, he showed decreased consciousness. Magnetic resonance imaging (MRI) showed edematous change with high signal and increased perfusion in the left hemisphere. Our case shows that delayed cerebral hyperperfusion syndrome can occur even 2 weeks after carotid artery stenting and multimodal MRI can help accurate diagnosis.

ERCP-related Cardiopulmonary Complications / 대한췌담도학회지

Cardiopulmonary complications of endoscopic retrograde cholangiopancreatography are rare, but they can cause serious morbidity and even possibly lead to death. Complications include cardiovascular events such as cardiac arrhythmias, hypotension and myocardiac infarction and respiratory-related complications like respiratory depression, hypoxia and aspiration. In many cases, these complications are a direct or indirect consequence of elderly or at-risk patients, and these problems may also arise from medications used for sedation and analgesia. Careful evaluation for high-risk patients before procedure and close cardiopulmonary monitoring during and after procedure should be warranted to reduce complications.

ERCP-related Cardiopulmonary Complications / 대한췌담도학회지

Cardiopulmonary complications of endoscopic retrograde cholangiopancreatography are rare, but they can cause serious morbidity and even possibly lead to death. Complications include cardiovascular events such as cardiac arrhythmias, hypotension and myocardiac infarction and respiratory-related complications like respiratory depression, hypoxia and aspiration. In many cases, these complications are a direct or indirect consequence of elderly or at-risk patients, and these problems may also arise from medications used for sedation and analgesia. Careful evaluation for high-risk patients before procedure and close cardiopulmonary monitoring during and after procedure should be warranted to reduce complications.

Adenomyoma in the Body of Stomach Presenting as a Pedunculated Polyp Treated by Endoscopic Mucosal Resection

An adenomyoma is a rare, benign tumor, characteristically composed of a mixture of glandular structures with intervening bundles of smooth muscle. An adenomyoma is considered to be a variant of an ectopic pancreas, without exocrine or endocrine components. Adenomyomas of the gastrointestinal tract are found most frequently in the stomach and the small intestine is rarely involved. Gastric adenomyoma is frequently localized in the antrum or pylorus and very rarely occurs in the body. Adenomyomas often appear as a submucosal mass. A 48-year-old man was referred for further management of a 2.5-cm pedunculated polyp in the stomach. The resected tumor was diagnosed as an adenomyoma of the stomach. To the best of our knowledge, this is the first case reported in the literature of gastric adenomyoma that presented as a pedunculated polyp in the body and was treated completely with endoscopic resection.

Clinical Outcomes of Endoscopic Removal in Patients with Colorectal Polypoid Leiomyomas / 대한소화기학회지

BACKGROUND/AIMS: Although polypoid leiomyomas in the colon and rectum are rare, they are increasingly detected during colonoscopy. The aim of this study was to evaluate the efficacy and clinical outcomes of endoscopic removal for colorectal polypoid leiomyoma. METHODS: Data were retrospectively collected from 22 patients with polypoid leiomyoma arising from the muscularis mucosae in the colon and rectum who underwent endoscopic removal at single referral gastrointestinal endoscopy unit. Colonoscopic findings, endoscopic removal, success rates, complication rates (bleeding or perforation), pathologic characteristics, and recurrence rates were investigated. RESULTS: Most polypoid leiomyomas were small asymptomatic lesions less than 1 cm. The tumors were located predominantly in the left colon. Ten leiomyomas were removed using cold biopsy forceps, and 12 were resected by conventional polypectomy or endoscopic mucosal resection. All tumors arose from or involved the muscularis mucosa. There were no complications, such as bleeding or perforation. No local remnant lesions were found in 19 patients who underwent at least one follow-up colonoscopy. CONCLUSIONS: This case series represent cases of small colorectal polypoid leiomyoma that were safely removed endoscopically. An awareness of their endoscopic and clinic-pathological characteristics may provide safe treatment strategy for colonic leiomyomatous tumors of similar size in capable hands.

Concurrent and predictive validation of robotic simulator Tube 3 module

PURPOSE: We previously described a new procedure specific module (Tube 3) to allow the practice of vesicourethral anastomosis after robot-assisted radical prostatectomy. Herein, we report a predetermined proficiency level of Tube 3 and preliminary validation to explore whether this new module can lead to performance improvement in the da Vinci system. MATERIALS AND METHODS: Eight urology residents and three urology fellows performed the Tube 3 module 1 hour daily for 7 days. The learning curve was depicted through a scatterplot and the stable point was identified through the cumulative sum chart. Concurrent and predictive validations were performed with the da Vinci system. The mean time to complete the task and end product rating score between Tube 3 training group and no Tube 3 training group were compared. RESULTS: Concerning the learning curve, about 41 repetitions comprising about 5 hours were needed to achieve this stable point when the mean time to complete Tube of 384 seconds was set as a target. With regarding to the concurrent and predictive validation, there significant differences were evident in the mean time to complete 16 needle passages and the vesicourethral anastomosis and the end product rating score. CONCLUSIONS: The virtual reality (VR) simulator can yield sufficient improvement in technical performance in Tube 3 within 5 hours. The acquired proficiency can be transferable to the vesicourethral anastomosis using the da Vinci system.

Renal cryoablation of small renal masses: A Korea University experience

PURPOSE: To evaluate the perioperative, functional, and oncological outcomes of renal cryoablation (RC) of small renal masses (SRMs) performed in Korea University Hospital. MATERIALS AND METHODS: We reviewed an Institutional Review Board-approved database of 70 patients who underwent RC and were followed up for a minimum of 3 months by a single surgeon in Korea University Hospital from August 2007 to May 2014. Among these patients, 68 patients (79 renal masses) were enrolled in our research. We evaluated perioperative, functional, and oncologic outcomes of RC. RESULTS: A total of 68 patients (79 renal masses) underwent RC in our institution. The mean age of the patients was 62.0 years. The mean tumor size was 2.25 cm. Among the 59 patients who underwent laparoscopic surgery, only 1 patient (1.47%) was converted to open surgery. No other perioperative complications occurred. The mean preoperative and 1-month postoperative estimated glomerular filtration ratio (eGFR) were 71.8 and 68.3 mL/min/1.73 m2, respectively (p=0.19). The mean 1-year postoperative eGFR was 65.0 mL/min/1.73 m2 (p=0.25). The mean follow-up period was 59.76 months (range, 3-119 months). Local tumor recurrence occurred in eight tumors (15.4%; a total of 52 renal cell carcinomas). Concerning treatment in the patients with recurrence, five patients underwent re-treatment and three patients are under active surveillance. None of the eight patients who experienced local recurrence had additional recurrence or tumor progression during the follow-up period. In our study, the recurrence-free rate was 83.0% and the cancer-specific survival rate was 100%. Moreover, the 5- and 10-year overall survival rates were both 100%. CONCLUSIONS: Long-term experience with RC in our institution demonstrates that RC is a safe and effective treatment for patients with SRMs.

Standardized analysis of complications after robot-assisted radical cystectomy: Korea University Hospital experience

PURPOSE: To analyze the complications after robot-assisted radical cystectomy (RARC) by use of a standardized reporting methodology by a single surgeon. MATERIALS AND METHODS: We prospectively reviewed a maintained institutional database of 52 patients who underwent RARC to manage bladder cancer and were followed up in 3 months by a single surgeon at Korea University Medical Center from 2007 through 2014. All complications within 90 days of surgery were defined and categorized into 5 grades according to the Clavien-Dindo classification. Logistic regression analysis was used to identify predictors of complications. RESULTS: Fifty percent of patients (26 of 52) experienced a complication of any grade <90 days after surgery, and 11 patients (21.2%) experienced a major complication. Complications were grouped in systems-based categories. Fifty complications occurred in 52 patients and hematologic complication (transfusion) was the most common (13 of 52). Wound dehiscence, anastomotic leakage, urinary tract obstruction, mechanical obstruction, and thromboembolism occurred as major complications. Mean estimated blood loss (EBL) was 247 mL and mean total operative time was 496 minutes. The mean number of lymph nodes harvested was 24.6, with 30.5 for extended dissection. EBL (over 300 mL), operative time, and method of urinary diversion were significant negative predictors of minor complications, whereas EBL (over 300 mL) was a significant negative predictor of major complications (p<0.05). CONCLUSIONS: The present results show that the complication rate reported by use of a standardized methodology after robotic radical cystectomy is still considerable although comparable to that of contemporary robot series. EBL, operative time, and diversion methods were predictors of complications.

Tumor-Specific Immunity Induced by Cryoablation in a Murine Renal Cell Carcinoma Model

PURPOSE: To evaluate tumor-specific immunity and define the mechanisms involved in the cryoimmunologic response, we compared the tumor control efficacy and immunologic responses of cryoablation with those of surgical excision in a tumor rechallenge model. MATERIALS AND METHODS: Sixty BALB/c mice with RENCA tumors that were generated in the left flank area underwent cryoablation or radical excision. The mice successfully treated were rechallenged with RENCA or an undifferentiated colon carcinoma cell line, CT26, in the contralateral right flank area. The recurrence rate after tumor rechallenge in each group was then observed. To assess the immunologic response of each treatment modality, fluorescent-activated cell sorting (FACS) analysis and a cytotoxicity assay using 51Cr release were performed. RESULTS: After reinoculation of the RENCA cells, the rate of tumor growth was significantly higher in the surgical excision group than in the cryoablation group (94.4% vs. 11.1%, p=0.001). In the cryoablation group, the tumor growth rate was significantly increased after rechallenge of CT26 cells compared with RENCA (94.1% vs. 11.1%, p=0.001). The cryoablation group showed an elevated CD3, CD4, CD8 T, and natural killer cell count in the FACS analysis and also showed significantly increased cytotoxicity in the 51Cr release assay compared with the excision group. CONCLUSIONS: These results showed that cryoablation, compared to surgical resection, was more effective in preventing tumor growth after rechallenge with RENCA cells and that this response was tumor-specific, because the CT26 cells did not have the same effect.

Sequential Changes in Aberrant Crypt Foci and Lectin Expression in the Early and Late Stages of DMH-Induced Colon Carcinogenesis in Rats

BACKGROUND/AIMS: The purpose of this study was to investigate the malignant potential of aberrant crypt foci (ACF) by measuring the multiplicity of crypts and lectin expression in the early and late stages of 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis. METHODS: Six-week-old Wistar rats were injected subcutaneously with DMH for 27 weeks. We classified ACF according to the number of crypts per ACF as a few crypts ( or =4 crypts, NC ACF). Immunohistochemistry was used to evaluate lectin expression. RESULTS: In the early stage, FC ACF (590/1,902, 31.0%) occurred more frequently than NC ACF (35/449, 7.8%); whereas in the late stage, NC ACF (176/449, 39.2%) occurred more frequently than FC ACF (324/1,902, 17.0%). The number of ACF peaked at 15 to 20 weeks. The ratio of NC/FC ACF increased gradually during carcinogenesis. The expression of both UEA1 and PNA was higher in NC ACF than FC ACF. Lectin expression increased in the late stage compared with the early stage. CONCLUSIONS: The expression of lectin was higher in NC ACF and ACF in the late stage. Therefore, ACF with higher multiplicities in the late stage may have more malignant potential in DMH-induced colon carcinogenesis.

The Relationship between Gastric Juice Nitrate/Nitrite Concentrations and Gastric Mucosal Surface pH

PURPOSE: To investigate gastric juice nitrate/nitrite concentration according to mucosal surface pH extent (area) of gastric corpus intimately contacting the gastric juice. MATERIALS AND METHODS: We included ninety-nine patients with dyspepsia. To evaluate gastric mucosal surface pH and its extent, gastric chromosocpy was performed by spraying phenol red dye on the corpus mucosa and estimating the extent of area with color changed. Nitrate/nitrite concentrations and pH of gastric juice were measured by ELISA and pH meter, respectively. Silver staining was done to histologically confirm the presence of Helicobacter pylori. RESULTS: Intragastric nitrate/nitrite concentrations in patients, showing phenol red staining mucosa were higher than those of unstaining mucosa (p=0.001): the more extensive in the area of phenol red staining area of corpus, the higher gastric juice pH found (r=0.692, p<0.001). Furthermore, the intragastric nitrate/nitrite concentrations correlated positively with gastric juice pH (r=0.481, p<0.001). CONCLUSION: The changes of mucosal surface pH and its extent in gastric corpus might affect either pH or nitrate/nitrite level of gastric juice.

DNA Double Strand Breaks in Gastric Epithelium with Helicobacter pylori Infection / 대한소화기학회지

BACKGROUND/AIMS: DNA double strand breaks (DSB) is one of the critical types of DNA damage. If unrepaired, DSB is accumulated in the nucleus of cells, the cells become apoptotic or transform to tumor by way of genomic instability. Some of malignant cancers and its premalignant lesions were proven to have DSB in their nuclei. There was no report that Helicobacter pylori (H. pylori), the gastric carcinogen, induce DNA DSB in gastric epithelium in vivo. The aim of this study was to investigate whether H. pylori induce DSB in the gastric epithelial cells of chronic gastritis. METHODS: Immunohistochemical stains were performed for the DSB markers, phospho-53BP1 and gammaH2AX, in the gastric epithelium derived from 44 peptic ulcer disease patients before and after H. pylori eradication. DNA fragmentation assay was performed in the cell line to investigate the DNA damage by H. pylori infection. RESULTS: The mean expression score of gammaH2AX was significantly higher in the H. pylori infected gastric epithelium as compared to the H. pylori eradicated gastric epithelium (8.8+/-5.5 vs. 6.2+/-5.3 respectively; p=0.008). The expression score of phospho-53BP1 between before and after eradication of H. pylori was not statistically different, but tended to be higher in H. pylori infection. DNA fragmentation was developed significantly more in the cell lines after infection with H. pylori. CONCLUSIONS: DSB of DNA damage was typical feature of H. pylori infection in the gastric epithelium.