Investigation of disinfection failure of flexible gastrointestinal endoscope due to Burkholderia cepacia contamination in irrigation tubing.

BACKGROUND AND AIMS: This study aims to identify the cause of disinfection failure of multiple flexible gastrointestinal endoscopes and to enhance the cleaning and disinfection procedures. METHODS: Samples from endoscopy devices, surrounding objects, cleaning water, automatic sterilizer, and integrated endoscopic washing workstation in a Digestive Endoscopy Center were collected and analyzed for microbial contamination and DNA/gene contents, between May and July 2021. RESULTS: The sample analysis revealed that the sink irrigation tubing of the washing workstation was contaminated with Burkholderia cepacia. After effective disinfection measures, the B. cepacia detection in the disinfected endoscope dropped from 13.23% to 0% (p=0.041). The presence of B. cepacia was confirmed through homology search and gene sequencing. CONCLUSIONS: The primary reason for endoscope disinfection failure is the contamination of the sink irrigation tubing by the B. cepacia bacteria. These findings emphasize the need for thorough cleaning of irrigation tubings in integrated endoscopic washing workstations, which is generally neglected in routine maintanance.

What is the best therapeutic strategy for colonoscopy of colorectal neoplasia? Future perspectives from the East.

Development and improvement of endoscopic techniques and devices have changed the treatment of colorectal tumors over the last decade. For the treatment of diminutive polyps, the cold snare technique of the West is becoming a promising treatment in the East because of its short procedure time and low rate of delayed bleeding by eliminating the delayed effect of electrocautery. Rather than using piecemeal endoscopic mucosal resection or surgical resection for the treatment of large superficial tumors, the technique of the East of endoscopic submucosal dissection (ESD) achieves a high success rate of en bloc R0 resection, enabling detailed pathological evaluation with less invasive treatment. This procedure should also be useful in the West where large colorectal tumors are more frequent than in the East. Regarding outcomes, however, in the literature, the definition of 'curative resection' remains somewhat inconsistent and long-term outcomes of patients with deep submucosal and/or lymphovascular invasion in the en bloc specimen have not yet been determined. Large prospective, as well as retrospective, studies of these patients are warranted. When colorectal ESD is difficult because of size or location, the pocket-creation method and/or double-balloon-assisted technique may be useful. In the East, high-quality magnified chromoendoscopy is widely available, and endoscopists try to identify focal submucosal invasion. In the West, a systematic evaluation of surveillance for the prevention of colorectal cancer has been done and is highly refined. The East and West have much to learn from each other.

Catheter-free method is sufficient for preparation for transnasal endoscopy: randomized controlled trial.

BACKGROUND AND AIM: Although transnasal endoscopy (TNE) is generally a comfortable and safe procedure, it has some disadvantages, such as complicated preprocessing and occasional repulsion reaction during catheterization. In an attempt to simplify the preprocessing method, the efficacy of a catheter-free method in which a catheter is not inserted into the nasal cavity was assessed. METHODS: The present study was a prospective, open-label, single-center, randomized controlled study with parallel assignment allocation 1:1. Between March 2009 and August 2009, a total of 93 TNE-naïve patients were enrolled and randomized. Patients were prospectively randomized into two groups (catheter-free vs catheter-insertion method). Patients who prepared according to the catheter-free method and who were unsuccessful underwent the catheter-insertion method. Clinical characteristics, success rate, complications, vital signs, acceptability, and tolerability were assessed and compared. RESULTS: Success rates of the catheter-free and catheter-insertion methods were 88% (n=44) and 88% (n=38) (P>0.05), respectively. Causes of failure in the catheter-free method included severe rhinalgia (n=1, 2%) and narrowing of the nasal cavity (n=5, 10%). Causes of failure in the catheter-insertion method included narrowing of the nasal cavity (n=5, 11%). Six patients whose TNE failed with the catheter-free method also experienced failed TNE with the catheter-insertion method. There were no statistical differences in vital signs, acceptability, and tolerability. CONCLUSION: The catheter-free method is sufficient for preparation for TNE. The success rate of TNE depends more on the structure of the nasal cavity than the preprocessing method.

Ravulizumab can effectively treat ischemic enteritis caused by paroxysmal nocturnal hemoglobinuria.

Ischemic colitis is a common disease with a good prognosis; however, complications can occur in the presence of a serious underlying disease. Herein, we present a case report in which characteristic findings on lower gastrointestinal endoscopy led to a diagnosis of paroxysmal nocturnal hemoglobinuria (PNH). An 82-year-old woman visited our hospital for chronic heart and renal failure. She had a history of breast cancer, myocardial infarction, and hemorrhoidal fistula and was initially hospitalized for ischemic colitis. Subsequent lower gastrointestinal endoscopy revealed extensive ulcerative lesions in the ascending, transverse, and descending colon. Histopathologically, small vessels exhibited multiple fibrin thrombus formations. Based on histopathological and endoscopic results, the presence of an underlying disease was suspected. Flow cytometric analysis showed that erythrocytes and granulocytes had 5.5 and 86.4% CD55- and CD59-negative cells, respectively. The patient was ultimately diagnosed with PNH and considered severely ill, given the ischemic colitis-induced abdominal pain and the need for red blood cell transfusions (4-6 units per month). Accordingly, the patient was administered ravulizumab. Ischemic enteritis did not relapse following ravulizumab administration, and transfusion dependence improved. If a patient with ischemic colitis presents atypical lower gastrointestinal endoscopic findings, it is important to explore the presence of an underlying disease.

Clinical impact of gastrointestinal endoscopy on the early detection of pharyngeal squamous cell carcinoma: A retrospective cohort study.

BACKGROUND: In recent years, with the growing availability of image-enhanced gastrointestinal endoscopy, gastroenterologists have contributed to the early detection of pharyngeal squamous cell carcinomas (SCC). AIM: To clarify the clinical characteristics of pharyngeal SCCs detected by gastrointestinal endoscopy. METHODS: This is a retrospective cohort study conducted in a single-center, a university hospital in Japan. We retrospectively assessed the clinical records of 522 consecutive patients with oropharyngeal or hypopharyngeal SCC who were examined in our hospital between 2011 and 2018. The lesions were classified into two groups: Group GE (detected by gastrointestinal endoscopy) and Group non-GE (detected by means other than gastrointestinal endoscopy). The clinical characteristics were compared between the two groups. Continuous data were compared using the Mann-Whitney U test. Pearson's χ 2 test or Fisher's exact test was used to analyze the categorical data and compare proportions. The Kaplan-Meier method was used to estimate the cumulative patient survival rates. RESULTS: In our study group, the median age was 65 years and 474 patients (90.8%) were male. One hundred and ninety-six cases (37.5%) involved the oropharynx and 326 cases (62.5%) involved the hypopharynx. Three hundred and ninety-five cases (75.7%) had some symptoms at the time of diagnosis. One hundred and forty-five (27.8%) cases had concurrent ESCC or a history of ESCC. One hundred and sixty-four (31.4%) cases were detected by gastrointestinal endoscopy and classified as Group GE. The proportions of asymptomatic cases, cTis-1 cases and cases with no lymph node metastasis were significantly higher in Group GE than Group non-GE (61.6% vs 7.3%, P < 0.001, 32.9% vs 12.0%, P < 0.001 and 69.5% vs 19.0%, P < 0.001). Endoscopic laryngo-pharyngeal surgery or endoscopic submucosal dissection were performed in only 0.6% of the lesions in Group non-GE but in 21.3% of the lesions in Group GE (P < 0.001). Overall survival was significantly longer in Group GE than in Group non-GE (P = 0.018). The 2-year and 4-year survival rates were 82.5% and 70.7% in Group GE, and 71.5% and 59.0% in Group non-GE, respectively. CONCLUSION: Gastrointestinal endoscopy plays an important role in the early detection and improving the prognosis of pharyngeal SCCs.

Development of a real-time spectral imaging system using in-site micro-LED-based illumination and high-speed micro-camera for endoscopic applications.

We designed a compact, real-time LED-based endoscopic imaging system for the detection of various diseases including cancer. In gastrointestinal applications, conventional endoscopy cannot reliably differentiate tumor from normal tissue. Current hyperspectral imaging systems are too slow to be used for real-time endoscopic applications. We are investigating real-time spectral imaging for different tissue types. Our objective is to develop a catheter for real-time hyperspectral gastrointestinal endoscopy. The endoscope uses multiple wavelengths within UV, visible, and IR light spectra generated by a micro-LED array. We capture images with a monochrome micro camera, which is cost-effective and smaller than the current hyperspectral imagers. A wireless transceiver sends the captured images to a workstation for further processing, such as tumor detection. The spatial resolution of the system is defined by camera resolution and the distance to the object, while the number of LEDs in the multi-wavelength light source determines the spectral resolution. To investigate the properties and the limitations of our high-speed spectral imaging approach, we designed a prototype system. We conducted two experiments to measure the optimal forward voltages and lighting duration of the LEDs. These factors affect the maximum feasible imaging rate and resolution. The lighting duration of each LED can be shorter than 10 ms while producing an image with a high signal-to-noise ratio and no illumination interference. These results support the idea of using a high-speed camera and an LED-array for real-time hyperspectral endoscopic imaging.

Two cases of gastric mucosa-associated lymphoid tissue (MALT) lymphoma masquerading as follicular gastritis.

In this report, we describe two cases of extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) of the stomach, which presented with multiple small, whitish nodules in the gastric body. The endoscopic appearance was similar to that of lymphoid follicular hyperplasia found in follicular gastritis or nodular gastritis. Both patients were positive for Helicobacter pylori, and the eradication treatment resulted in complete remission of the lymphoma. However, recurrence was noted in one patient. These cases indicate that, although infrequent, gastric MALT lymphoma can show a nodular appearance resembling that of follicular gastritis.

High-quality endoscope reprocessing decreases endoscope contamination.

OBJECTIVES: Several outbreaks of severe infections due to contamination of gastrointestinal (GI) endoscopes, mainly duodenoscopes, have been described. The rate of microbial endoscope contamination varies dramatically in literature. The aim of this multicentre prospective study was to evaluate the hygiene quality of endoscopes and automated endoscope reprocessors (AERs) in Tyrol/Austria. METHODS: In 2015 and 2016, a total of 463 GI endoscopes and 105 AERs from 29 endoscopy centres were analysed by a routine (R) and a combined routine and advanced (CRA) sampling procedure and investigated for microbial contamination by culture-based and molecular-based analyses. RESULTS: The contamination rate of GI endoscopes was 1.3%-4.6% according to the national guideline, suggesting that 1.3-4.6 patients out of 100 could have had contacts with hygiene-relevant microorganisms through an endoscopic intervention. Comparison of R and CRA sampling showed 1.8% of R versus 4.6% of CRA failing the acceptance criteria in phase I and 1.3% of R versus 3.0% of CRA samples failing in phase II. The most commonly identified indicator organism was Pseudomonas spp., mainly Pseudomonas oleovorans. None of the tested viruses were detected in 40 samples. While AERs in phase I failed (n = 9, 17.6%) mainly due to technical faults, phase II revealed lapses (n = 6, 11.5%) only on account of microbial contamination of the last rinsing water, mainly with Pseudomonas spp. CONCLUSIONS: In the present study the contamination rate of endoscopes was low compared with results from other European countries, possibly due to the high quality of endoscope reprocessing, drying and storage.

A pilot study on using chlorine dioxide gas for disinfection of gastrointestinal endoscopes.

OBJECTIVES: This pilot study of employing chlorine dioxide (CD) gas to disinfect gastrointestinal endoscopes was conducted to meet the expectations of many endoscopy units in China for a high-efficiency and low-cost disinfectant. METHODS: An experimental prototype with an active circulation mode was designed to use CD gas to disinfect gastrointestinal endoscopes. One type of testing device composed of polytetrafluoroethylene (PTFE) tubes (2 m long, inner diameter 1 mm) and bacterial carrier containers was used to simulate the channel of the endoscope. PTFE bacterial carriers inoculated with Bacillus atrophaeus with or without organic burden were used to evaluate the sporicidal activity of CD gas. Factors including exposure dosage, relative humidity (RH), and flow rate (FR) influencing the disinfection effect of CD gas were investigated. Moreover, an autoptic disinfecting test on eight real gastrointestinal endoscopes after clinical use was performed using the experimental prototype. RESULTS: RH, exposure dosage, organic burden, and the FR through the channel significantly (P<0.05) affected the disinfection efficacy of CD gas for a long and narrow lumen. The log reduction increased as FR decreased. Treatment with 4 mg/L CD gas for 30 min at 0.8 L/min FR and 75% RH, resulted in complete inactivation of spores. Furthermore, all eight endoscopes with a maximum colony-forming unit of 915 were completely disinfected. The cost was only 3 CNY (0.46 USD) for each endoscope. CONCLUSIONS: The methods and results reported in this study could provide a basis for further studies on using CD gas for the disinfection of endoscopes.

Primary intestinal follicular lymphoma: How to identify follicular lymphoma by routine endoscopy.

A 69-year-old Japanese female was diagnosed with primary intestinal follicular lymphoma. Esophagogastroduodenoscopy with high-definition imaging revealed not only the typical feature of whitish polyps of up to 2 mm in diameter in the duodenal second and third portions, but also more detailed morphology, such as enlarged whitish villi and tiny whitish depositions. These findings appeared to reflect the pathological structures; infiltration of lymphoma cells into the villi were probably seen as enlargement of the villi, and the formation of lymphoid follicles were shown as opaque white spots or tiny white depositions. Thus, the above features might contribute to the distinct diagnosis of intestinal follicular lymphoma. This case indicates that routine esophagogastroduodenoscopy can visualize microsurface structures, which can be pathognomonic and help to diagnose intestinal follicular lymphoma, even without magnifying endoscopy.