Removal of diminutive colorectal polyps: A prospective randomized clinical trial between cold snare polypectomy and hot forceps biopsy

AIM To compare the efficacy and safety of cold snare polypectomy(CSP) and hot forceps biopsy(HFB) for diminutive colorectal polyps.METHODS This prospective, randomized single-center clinical trial included consecutive patients ≥ 20 years of age with diminutive colorectal polyps 3-5 mm from December 2014 to October 2015. The primary outcome measures were en-bloc resection(endoscopic evaluation) and complete resection rates(pathological evaluation). The secondary outcome measures were the immediate bleeding or immediate perforation rate after polypectomy, delayed bleeding or delayed perforation rate after polypectomy, use of clipping for bleeding or perforation, and polyp retrieval rate. Prophylactic clipping after polyp removal wasn't routinely performed.RESULTS Two hundred eight patients were randomized into the CSP(102), HFB(106) and 283 polyps were evaluated(CSP: 148, HFB: 135). The en-bloc resection rate was significantly higher with CSP than with HFB [99.3%(147/148) vs 80.0%(108/135), P < 0.0001]. The complete resection rate was significantly higher with CSP than with HFB [80.4%(119/148) vs 47.4%(64/135), P < 0.0001]. The immediate bleeding rate was similar between the groups [8.6%(13/148) vs 8.1%(11/135), P = 1.000], and endoscopic hemostasis with hemoclips was successful in all cases. No cases of perforation or delayed bleeding occurred. The rate of severe tissue injury to the pathological specimen was higher HFB than CSP [52.6%(71/135) vs 1.3%(2/148), P < 0.0001]. Polyp retrieval failure was encountered CSP(7), HFB(2).CONCLUSION CSP is more effective than HFB for resecting diminutive polyps. Further long-term follow-up study is required.

Autoimmune hepatitis and IgG4-related disease

IgG4-related disease(IgG4-RD) is a chronic-fibroinflammatory disorder affecting a wide range of organs. Elevation of serum IgG4 concentrations and abundant infiltration of IgG4-expressing plasma cells are key diagnostic features of this autoimmune disease. Although common organ involvement of IgG4-RD includes the salivary glands, pancreas, and bile duct, hepatic involvement is less well established. Recently, five studies identified a subtype of autoimmune hepatitis(AIH), called IgG4-associated AIH(IgG4-AIH). IgG4-AIH is diagnosed based on significant accumulation of IgG4-expressing plasmacytes in the liver in patients who met the diagnostic criteria for classical AIH. Although four of the five reports regarded IgG4-AIH based on hepatic accumulation of IgG4-positive cells alone, one report diagnosed IgG4-AIH based on both hepatic accumulation of IgG4-positive cells and elevated serum concentrations of IgG4. IgG4-AIH diagnosed based on the latter criteria may be a hepatic manifestation of IgG4-RD whereas IgG4-AIH diagnosed based on the former criteria may be a subtype of AIH. In this review article, we summarize and discuss clinicopathological features of IgG4-AIH.

Biomarkers in autoimmune pancreatitis and immunoglobulin G4-related disease

Solitary organ autoimmune disorders,formerly known as autoimmune pancreatitis(AIP),autoimmune sialadenitis,and autoimmune sclerosing cholangitis,are now considered organ-specific manifestations of systemic immunoglobulin G4-related disease(IgG4-RD).AIP and IgG4-RD are characterized by elevated serum concentration of IgG4 antibody(Ab),accumulation of IgG4-expressing plasmacytes in the affected organs,and involvement of multiple organs.It is well established that enhanced IgG4 Ab responses are a hallmark of AIP and IgG4-RD for diagnosis and monitoring disease activity.However,a significant fraction of patients with AIP and IgG4-RD who develop chronic fibroinflammatory responses have normal serum concentrations of this IgG subtype.In addition,disease flare-up is sometimes seen even in the presence of normalized serum concentrations of IgG4 Ab after successful induction of remission by prednisolone.Therefore,it is necessary to identify new biomarkers based on the understanding of the pathophysiology of AIP and IgG4-RD.Recently,we found that activation of plasmacytoid dendritic cells producing both interferon-α(IFN-α)and interleukin-33(IL-33)mediate murine AIP and human IgG4-RD.More importantly,we provided evidence that serum concentrations of IFN-αand IL-33 could be useful biomarkers for the diagnosis and monitoring of AIP and IgG4-RD activity after induction of remission in these autoimmune disorders.In this Frontier article,we have summarized and discussed biomarkers of AIP and IgG4-RD,including Igs,autoAbs,and cytokines to provide useful information not only for clinicians but also for researchers.

Endoscopic ultrasound-guided gallbladder drainage for acute cholecystitis: Long-term outcomes after removal of a self-expandable metal stent

AIM To assess the long-term outcomes of this procedure after removal of self-expandable metal stent(SEMS). The efficacy and safety of endoscopic ultrasoundguided gallbladder drainage(EUS-GBD) with SEMS were also assessed.METHODS Between January 2010 and April 2015, 12 patients with acute calculous cholecystitis, who were deemed unsuitable for cholecystectomy, underwent EUSGBD with a SEMS. EUS-GBD was performed under the guidance of EUS and fluoroscopy, by puncturing the gallbladder with a needle, inserting a guidewire, dilating the puncture hole, and placing a SEMS. TheSEMS was removed and/or replaced with a 7-Fr plastic pigtail stent after cholecystitis improved. The technical and clinical success rates, adverse event rate, and recurrence rate were all measured.RESULTS The rates of technical success, clinical success, and adverse events were 100%, 100%, and 0%, respectively. After cholecystitis improved, the SEMS was removed without replacement in eight patients, whereas it was replaced with a 7-Fr pigtail stent in four patients. Recurrence was seen in one patient(8.3%) who did not receive a replacement pigtail stent. The median follow-up period after EUS-GBD was 304 d(78-1492).CONCLUSION EUS-GBD with a SEMS is a possible alternative treatment for acute cholecystitis. Long-term outcomes after removal of the SEMS were excellent. Removal of the SEMS at 4-wk after SEMS placement and improvement of symptoms might avoid migration of the stent and recurrence of cholecystitis due to food impaction.

Risk factors for local recurrence and appropriate surveillance interval after endoscopic resection

BACKGROUND Risk factors for local recurrence after polypectomy, endoscopic mucosal resection(EMR), and endoscopic submucosal dissection(ESD) have not been identified.Additionally, the appropriate interval for endoscopic surveillance of colorectal tumors at high-risk of local recurrence has not been established.AIM To clarify the clinicopathological characteristics of recurrent lesions after endoscopic colorectal tumor resection and determine the appropriate interval.METHODS Three hundred and sixty patients(1412 colorectal tumors) who underwent polypectomy, EMR, or ESD and received endoscopic surveillance subsequently for more than one year to detect local recurrence were enrolled in this study. The clinicopathological factors associated with local recurrence were determined via univariate and multivariate analyses.RESULTS Local recurrence was observed in 31 of 360(8.6%) patients [31 of 1412(2.2%)lesions] after colorectal tumor resection. Piecemeal resection, tumor size of more than 2 cm, and the presence of villous components were associated with colorectal tumor recurrence after endoscopic resection. Of these three factors, the piecemeal resection procedure was identified as an independent risk factor for recurrence. Colorectal tumors resected into more than five pieces were associated with a high risk of recurrence since the average period from resection torecurrence in these cases was approximately 3 mo. The period to recurrence in cases resected into more than 5 pieces was much shorter than that in those resected into less than 4 pieces(3.8 ± 1.9 mo vs 7.9 ± 5.0 mo, P < 0.05).CONCLUSION Local recurrence of endoscopically treated colorectal tumors depends upon the outcome of first endoscopic procedure. Piecemeal resection was the only significant risk factor associated with local recurrence after endoscopic resection.

Nucleotide-binding oligomerization domain 1 and Helicobacter pylori infection: A review

Nucleotide-binding oligomerization domain 1(NOD1) is an intracellular innate immune sensor for small molecules derived from bacterial cell components. NOD1 activation by its ligands leads to robust production of pro-inflammatory cytokines and chemokines by innate immune cells, thereby mediating mucosal host defense systems against microbes. Chronic gastric infection due to Helicobacter pylori(H. pylori) causes various upper gastrointestinal diseases, including atrophic gastritis, peptic ulcers, and gastric cancer. It is now generally accepted that detection of H. pylori by NOD1 expressed in gastric epithelial cells plays an indispensable role in mucosal host defense systems against this organism. Recent studies have revealed the molecular mechanism by which NOD1 activation caused by H. pylori infection is involved in the development of chronic gastritis and gastric cancer. In this review, we have discussed and summarized how sensing of H. pylori by NOD1 mediates the prevention of chronic gastritis and gastric cancer.

Alterations of autophagic and innate immune responses by the Crohn’s disease-associated ATG16L1 mutation

Crohn’s disease(CD)is driven by the loss of tolerance to intestinal microbiota and excessive production of pro-inflammatory cytokines.These pro-inflammatory cytokines are produced by macrophages and dendritic cells(DCs)upon sensing the intestinal microbiota by the pattern recognition receptors(PRRs).Impaired activation of PRR-mediated signaling pathways is associated with chronic gastrointestinal inflammation,as shown by the fact that loss-of-function mutations in the nucleotide-binding oligomerization domain 2 gene increase the risk of CD development.Autophagy is an intracellular degradation process,during which cytoplasmic nutrients and intracellular pathogens are digested.Given that impaired reaction to intestinal microbiota alters signaling pathways mediated by PRRs,it is likely that dysfunction of the autophagic machinery is involved in the development of CD.Indeed,the loss-of-function mutation T300A in the autophagy related 16 like 1(ATG16L1)protein,a critical regulator of autophagy,increases susceptibility to CD.Recent studies have provided evidence that ATG16L1 is involved not only in autophagy,but also in PRR-mediated signaling pathways.ATG16L1 negatively regulates pro-inflammatory cytokine responses of macrophages and DCs after these cells sense the intestinal microbiota by PRRs.Here,we discuss the molecular mechanisms underlying the development of CD in the T300A ATG16L1 mutation by focusing on PRR-mediated signaling pathways.

Clinical utility of treatment method conversion during single-session endoscopic ultrasound-guided biliary drainage

BACKGROUND Although several techniques for endoscopic ultrasound-guided biliary drainage(EUS-BD)are available at present,an optimal treatment algorithm of EUS-BD has not yet been established.AIM To evaluate the clinical utility of treatment method conversion during single endoscopic sessions for difficult cases in initially planned EUS-BD.METHODS This was a single-center retrospective analysis using a prospectively accumulated database.Patients with biliary obstruction undergoing EUS-BD between May 2008 and April 2016 were included.The primary outcome was to evaluate the improvement in EUS-BD success rates by converting the treatment methods during a single endoscopic session.Secondary outcomes were clarification of the factors leading to the conversion from the initial EUS-BD and the assessment of efficacy and safety of the conversion as judged by technical success,clinical success,and adverse events(AEs).RESULTS A total of 208 patients underwent EUS-BD during the study period.For 18.8%(39/208)of the patients,the treatment methods were converted to another EUSBD technique from the initial plan.Biliary obstruction was caused by pancreatobiliary malignancies,other malignant lesions,biliary stones,and other benign lesions in 22,11,4,and 2 patients,respectively.The reasons for the difficulty with the initial EUS-BD were classified into the following 3 procedures:Target puncture(n=13),guidewire manipulation(n=18),and puncture tract dilation(n=8).Technical success was achieved in 97.4%(38/39)of the cases and clinical success was achieved in 89.5%of patients(34/38).AEs occurred in 10.3%of patients,including bile leakage(n=2),bleeding(n=1),and cholecystitis(n=1).The puncture target and drainage technique were altered in subsequent EUSBD procedures in 25 and 14 patients,respectively.The final technical success rate with 95%CI for all 208 cases was 97.1%(95%CI:93.8%-98.9%),while that of the initially planned EUS-BD was 78.8%(95%CI:72.6%-84.2%).CONCLUSION Among multi-step procedures in EUS-BD,guidewire manipulation appeared to be the most technically challenging.When initially planned EUS-BD is technically difficult,treatment method conversion in a single endoscopic session may result in successful EUS-BD without leading to severe AEs.

Castor oil as booster for colon capsule endoscopy preparation reduction: A prospective pilot study and patient questionnaire

BACKGROUND Preparation for colon capsule endoscopy(CCE)requires a large liquid laxative volume for capsule excretion,which compromises the procedure's tolerability.AIM To assess the safety and utility of castor oil-boosted bowel preparation.METHODS This prospective cohort study including 20 patients(age range,16-80 years;six men and 14 women)suspected of having colorectal disease was conducted at Kindai University Hospital from September 2017 to August 2019.All patients underwent CCE because of the following inclusion criteria:previous incomplete colonoscopy in other facility(n=20),history of abdominal surgery(n=7),or organ abnormalities such as multiple diverticulum(n=4)and adhesion after surgery(n=6).The exclusion criteria were as follows:Dysphagia,history of allergic reactions to the drugs used in this study(magnesium citrate,polyethylene glycol,metoclopramide,and castor oil),possibility of pregnancy,possibility of bowel obstruction or stenosis based on symptoms,or scheduled magnetic resonance imaging within 2 wk after CCE.The primary outcome was the capsule excretion rate within the battery life,as evaluated by the total large bowel observation rate,large bowel transit time,and bowel creasing level using a fivegrade scale in different colorectal segments.The secondary outcomes were complications,colorectal lesion detection rates,and patients’tolerability.RESULTS The castor oil-based regimen was implemented in 17 patients.Three patients cancelled CCE because they could tolerate castor oil,but not liquid laxatives.The capsule excretion rate within the battery life was 88%(15/17).The mean large bowel transit time was 236 min.Approximately 70%of patients had satisfactory colon cleansing levels.CCE detected colon polyps(14/17,82%)and colonic diverticulum(4/12,33%).The sensitivity,specificity,and diagnostic accuracy rates for detecting colorectal polyps(size≥6 mm)were 76.9%,75.0%,and 76.4%,respectively.The sensitivity,specificity,and diagnostic accuracy rates for detection of diverticulum were 100%each.Twelve patients(71%)rated CCE as more than“good”,confirming the new regimen’s tolerability.No serious adverse events occurred during this study.CONCLUSION The castor oil-based regimen could reduce bowel preparation dose and improve CCE tolerability.

Proposal of Walking to Prevent a Fall of a Planetary Exploration Legged Rover Using Effect of Loose Soil Caused by a Propagation of Vibration

In this study,a walking method that prevents a fall of the planetary exploration-legged rover is proposed.In the proposed walking method,the leg is sunk by giving vibration to the ground.The posture of the rover is changed to prevent a fall of the rover by sinking the leg.First,the relationship between the kind of vibration and the subsidence of the leg is confirmed.In this experimental result,the leg is shown to be easy to sink to the ground by giving vibration.Moreover,the larger the vibratory force is,the easier the leg sinks to the ground.Finally,the legged testbed walks on the loose ground with a slope using the proposed walking method.In this experimental result,the testbed is difficult to fall down when it uses the proposed walking.Moreover,the angle of a slope that the testbed can walk becomes large by using the proposed walking.

疣状胃窦炎与幽门螺杆菌感染、营养状态及胃黏膜萎缩的相关性

背景:英文文献中鲜有关于疣状胃窦炎(VG)的报道。本研究旨在分析VG的临床和内镜特征,重点关注幽门螺杆菌(Hp)感染、营养及胃黏膜萎缩。方法:本回顾性研究的对象为接受常规靛蓝胭脂红染色内镜检查的患者,对其中VG阳性与VG阴性病例进行比较。基于疣状病变的数量和分布,将VG进一步分为经典型和多灶型。收集人口统计学、临床及内镜资料,包括体质指数、血清白蛋白、胆固醇、胃黏膜萎缩、反流性食管炎、Barrett食管及Hp感染情况等。采用单因素和多因素分析明确VG发生的相关因素。结果:我们分析了621例常规内镜检查病例的相关资料,发现VG病例(352例)体质指数相对较高(OR 1.12,95%CI:1.05-1.18,P<0.01),更多伴随反流性食管炎(OR 1.96,95%CI:1.10-3.28,P<0.01),Hp阴性者比例更高,无论既往有Hp根治史(OR 9.94,95%CI:6.00-16.47,P<0.01)还是无Hp根治史(OR 6.12,95%CI:3.51-10.68,P<0.01)。与经典型VG相比,多灶型VG病例更多出现胃黏膜萎缩,包括闭锁型萎缩(OR 9.90,95%CI:4.04-21.37,P<0.001)和开放型萎缩(OR 8.10,95%CI:3.41-19.24,P<0.001)。年龄、性别、总胆固醇、血清白蛋白及胆汁色胃液方面的组间差异均无统计学意义。结论:VG的发生与高体质指数、反流性食管炎及Hp阴性有关;多灶型VG则多伴有胃黏膜萎缩。这些结果提示VG可能是一种由高胃酸状态、胃负荷过重及胃黏膜脆弱所引起的生理现象。