齊藤 景子

Background/Aims: Esophageal motility disorders (EMDs) contribute to the pathophysiology of gastroesophageal reflux disease. However, the causes of EMDs and their impact on gastroesophageal reflux disease-associated symptoms remain unknown. This study aims to elucidate clinical features associated with various types of EMDs in patients with heartburn symptoms. Methods: Of the 511 patients who underwent high-resolution manometry, 394 who were evaluated for heartburn symptoms were examined. Patients subjected to high-resolution manometry were classified into 4 groups: outflow obstruction group, hypermotility group, hypomotility group, and normal motility group. Symptoms were evaluated using 3 questionnaires. Patient characteristics and symptoms for each EMD type were compared with those of the normal motility group. Results: Of the 394 patients, 193 (48.9%) were diagnosed with EMDs, including 71 with outflow obstruction, 15 with hypermotility, and 107 with hypomotility. The mean dysphagia score was significantly higher in each of the 3 EMD groups compared with those with normal motility. The mean acid reflux and dyspepsia scores were significantly lower in the outflow obstruction group (P < 0.05). The mean body mass index and median Brinkman index were significantly higher in the hypermotility group (P = 0.001 and P = 0.018, respectively), whereas the mean diarrhea and constipation scores were significantly lower in the hypomotility group (P < 0.05). Conclusions: The results of our study indicate that different EMDs have distinct characteristics. Cigarette smoking and high body mass index were associated with esophageal hypermotility. Assessment of the dysphagia symptom scores may help identify patients with EMDs.

The genetic characteristics of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) in the Japanese population is unclear. This study aims to investigate the genetic characteristics from nondysplastic BE (NDBE) to early EAC in Japan. Clinical information was collected. Moreover, the genetic profile of NDBE without concurrent dysplasia, early EAC, and surrounding BE were also investigated using endoscopic biopsy samples and formalin-fixed, paraffin-embedded specimens from Japanese patients by targeted next-generation sequencing. Immunohistochemical staining for p53 was also performed for EAC lesions. Targeted NGS was performed for 33 cases with 77 specimens. No significant difference exists in the NDBE group between the number of putative drivers per lesion in the short-segment Barrett's esophagus (SSBE) and long-segment Barrett's esophagus (LSBE) [0 (range, 0-1) vs. 0 (range, 0-1). p = 1.00]. TP53 putative drivers were found in two patients (16.7%) with nondysplastic SSBE. TP53 was the majority of putative drivers in both BE adjacent to EAC and EAC, accounting for 66.7% and 66.7%, respectively. More putative drivers per lesion were found in the EAC than in the NDBE group [1 (range, 0-3) vs. 0 (range, 0-1). p < 0.01]. The genetic variants of TP53 in the Japanese early EAC were similar to those in western countries. However, TP53 putative drivers were detected even in Japanese patients with nondysplastic SSBE. This is significant because such nondysplastic SSBE might have higher risk of progressing to high-grade dysplasia or EAC. The risks of progression may not be underestimated and appropriate follow-ups may be necessary even in patients with SSBE.Trial registration: This study was registered at the University Hospital Medical Information Network (UMIN000034247).

BACKGROUND AND AIM: The effectiveness of cold snare polypectomy (CSP) for superficial non-ampullary duodenal epithelial tumors (SNADETs) regarding long-term outcomes is not fully clarified. This study aimed to investigate long-term outcomes of CSP for SNADETs. METHODS: Patients diagnosed with sporadic SNADETs and treated with CSP at Chiba University Hospital between March 2015 and May 2018 were retrospectively analyzed. Long-term outcomes, short-term outcomes, and adverse events were investigated. RESULTS: In total, 35 patients with 46 lesions were included. The en-bloc resection rate was 97.8%. Thirty-seven lesions (80.4%) were diagnosed as adenomatous. The R0 resection rate for adenomatous lesions was 70.3%. Follow-up investigations more than 12 months after CSP were completed for 35 adenomatous lesions (94.6%). The median observation period after CSP was 48 months. One patient whose observation period was only 3 months died from chronic heart failure with cardiac sarcoidosis 6 months after CSP. No patient died from SNADETs. The relapse-free survival rate at 12 months after CSP was 97.1%. One recurrence (2.7%) was observed 12 months after CSP. We removed the recurrence lesion with CSP and cold forceps polypectomy. No new recurrence occurred within the observation period. No perforation or post-operative bleeding occurred for CSP. CONCLUSIONS: Cold snare polypectomy for diminutive and small SNADETs is a safe and useful procedure with a high en-bloc resection rate and long-term local control capability.

BACKGROUND/AIM: Barrett's esophagus (BE) is a precursor of esophageal adenocarcinoma (EAC). Therefore, an accurate diagnosis of BE is important for the subsequent follow-up and early detection of EAC. However, the definitions of BE have not been standardized worldwide; columnar-lined epithelium (CLE) without intestinal metaplasia (IM) and/or < 1 cm is not diagnosed as BE in most countries. This study aimed to clarify the malignant potential of CLE without IM and/or < 1 cm genetically. METHOD: A total of 96 consecutive patients (including nine patients with EAC) who had CLE were examined. Biopsies for CLE were conducted, and patients were divided into those with IM and > 1 cm (Group A) and those without IM and/or < 1 cm (Group B). Malignant potential was assessed using immunochemical staining for p53. Moreover, causative genes were examined using next-generation sequencing (NGS) on ten patients without Helicobacter pylori infection and without atrophic gastritis. RESULT: Of the 96 patients, 66 were in Group B. The proportion of carcinoma/dysplasia in Group A was significantly higher than that in Group B (26.7% in Group A and 1.5% in Group B; p < 0.01). However, one EAC patient was found in Group B. In the immunostaining study for non-EAC patients, an abnormal expression of p53 was not observed in Group A, whereas p53 loss was observed in three patients (4.6%) in Group B. In the NGS study, a TP53 mutation was found in Group B. CONCLUSION: CLE without IM and/or < 1 cm has malignant potential. This result suggests that patients with CLE as well as BE need follow-up.

Somatic mutations including the background mucosa in patients with Lugol-voiding lesions (LVLs) are still not well known. The aim of this study was to evaluate the somatic mutations of the background mucosa in patients with LVLs (Squamous cell carcinoma (SCC), intraepithelial neoplasia (IN), and hyperplasia). Twenty-five patients with LVLs (9 with SCC, 6 with IN, and 10 with hyperplasia) were included. A targeted sequence was performed for LVLs and background mucosa using an esophageal cancer panel. Each mutation was checked whether it was oncogenic or not concerning OncoKB. In LVLs, TP53 was the most dominant mutation (80%). Furthermore, 72% of TP53 mutations was putative drivers. In background mucosa, NOTCH1 was the most dominant mutation (88%) and TP53 was the second most dominant mutation (48%). Furthermore, 73% of TP53 mutations and 8% of NOTCH1 mutations were putative drivers. Putative driver mutations of TP53 had significantly higher allele frequency (AF) in SCC than in IN and hyperplasia. Conversely, putative driver mutations of NOTCH1 did not have a significant accumulation of AF in the progression of carcinogenesis. Furthermore, in SCC, AF of TP53 mutations was significantly higher in LVLs than in background mucosa, but not in IN and hyperplasia. Regarding NOTCH1, a significant difference was not observed between LVLs and background mucosa in each group. The background mucosa in patients with LVLs already had putative driver mutations such as TP53 and NOTCH1. Of these two genes, TP53 mutation could be the main target gene of carcinogenesis in esophageal SCC. Clinical Trials registry: UMIN000034247.

In 2020, Olympus Medical Systems Corporation introduced the Texture and Color Enhancement Imaging (TXI) as a new image-enhanced endoscopy. This study aimed to evaluate the visibility of neoplasms and mucosal atrophy in the upper gastrointestinal tract through TXI. We evaluated 72 and 60 images of 12 gastric neoplasms and 20 gastric atrophic/nonatrophic mucosa, respectively. The visibility of gastric mucosal atrophy and gastric neoplasm was assessed by six endoscopists using a previously reported visibility scale (1 = poor to 4 = excellent). Color differences between gastric mucosal atrophy and nonatrophic mucosa and between gastric neoplasm and adjacent areas were assessed using the International Commission on Illumination L*a*b* color space system. The visibility of mucosal atrophy and gastric neoplasm was significantly improved in TXI mode 1 compared with that in white-light imaging (WLI) (visibility score: 3.8 ± 0.5 vs. 2.8 ± 0.9, p < 0.01 for mucosal atrophy; visibility score: 2.8 ± 1.0 vs. 2.0 ± 0.9, p < 0.01 for gastric neoplasm). Regarding gastric atrophic and nonatrophic mucosae, TXI mode 1 had a significantly greater color difference than WLI (color differences: 14.2 ± 8.0 vs. 8.7 ± 4.2, respectively, p < 0.01). TXI may be a useful observation modality in the endoscopic screening of the upper gastrointestinal tract.

症例は40歳代男性で、検診の上部消化管造影検査にて胃に隆起性病変を指摘された。拡大内視鏡観察、生検結果にて明らかな悪性所見は得られなかったものの、胃底腺型胃癌、神経内分泌腫瘍の可能性も否定できず、十分なinformed consentを行ったうえで内視鏡的粘膜下層剥離術を施行した。HE染色では、病変の立ち上がりは腸上皮化生を伴わない、よく保たれた胃底腺領域の粘膜が観察された。病変中央は腺窩上皮過形成性変化とともに、粘膜固有層深層において胃底腺とは異なる異所性胃腺を認めた。同部位では正常の胃底腺は欠損していた。異所性胃腺は病変中央の粘膜固有層深層のみでなく、周囲の胃底腺領域の粘膜固有層の深層にまで入り込んでいた。異所性胃腺はMUC6で染色され、幽門腺型腺管であることが示された。以上より、胃底腺領域内の腺窩上皮過形成を伴う異所性幽門腺粘膜と診断した。

The current study aimed to evaluate the efficacy of linked color imaging (LCI) in improving the visibility of superficial non-ampullary duodenal epithelial tumors (SNADETs). We prospectively evaluated 44 consecutive patients diagnosed with SNADETs. Three trainees and three experts assessed the visibility scores of white light imaging (WLI), LCI, and blue laser imaging-bright (BLI-b) for SNADETs, which ranged from 1 (not detectable without repeated cautious examination) to 4 (excellent visibility). In addition, the L* a* b* color values and color differences (ΔE*) were evaluated using the CIELAB color space system. For SNADETs, the visibility scores of LCI (3.53 ± 0.59) were significantly higher than those of WLI and BLI-b (2.66 ± 0.79 and 3.41 ± 0.64, respectively). The color differences (ΔE*) between SNADETs and the adjacent normal duodenal mucosa in LCI mode (19.09 ± 8.33) were significantly higher than those in WLI and BLI-b modes (8.67 ± 4.81 and 12.92 ± 7.95, respectively). In addition, the visibility score of SNADETs and the color differences in LCI mode were significantly higher than those in WLI and BLI-b modes regardless of the presence of milk white mucosa (MWM). LCI has potential benefits, and it is considered a promising clinical modality that can increase the visibility of SNADETs regardless of the presence of MWM.This study was registered at the University Hospital Medical Information Network (UMIN000028840).

Ineffective esophageal motility (IEM) is the most common manometric abnormality in gastroesophageal reflux disease (GERD). However, the impact of IEM on esophageal chemical clearance has not been fully investigated. This study aimed to determine the impact of IEM on esophageal chemical clearance in patients with GERD. A total of 369 patients with GERD symptoms who underwent upper endoscopy and high-resolution manometry (HRM) test were retrospectively analyzed. The relationship between IEM and erosive esophagitis was examined. In addition, the impact of IEM on chemical clearance was examined in patients who underwent an additional combined multichannel intraluminal impedance-pH (MII-pH) test. Esophageal chemical clearance capability was evaluated via postreflux swallow-induced peristaltic wave (PSPW) index and acid clearance time (ACT). Of 369 patients, 181 (49.1%) had esophageal motility disorders, of which 78 (21.1%) had IEM. The proportion of IEM patients in those with erosive esophagitis and those without were 16.2% and 21.7%, respectively, and no significant difference was observed (P = 0.53). After excluding patients other than those with IEM and normal esophageal motility, 64 subsequently underwent MII-pH test. The median values of the PSPW index in the IEM and normal esophageal motility group were 11.1% (4.2%-20.0%) and 17.1% (9.8%-30.6%), respectively. The PSPW index was significantly lower in the IEM group than in the normal esophageal motility group (P < 0.05). The median ACT values in the IEM group and normal esophageal motility group were 125.5 (54.0-183.5) seconds and 60.0 (27.2-105.7) seconds, respectively. The ACT was significantly longer in the IEM group than in the normal esophageal motility group (P < 0.05). In conclusion, IEM was found to be associated with chemical clearance dysfunction as measured against the PSPW index and ACT. As this condition could be a risk factor for GERD, future treatments should be developed with a focus on chemical clearance.

Objective: Long-term administration of proton pump inhibitors (PPIs) after eradication of Helicobacter pylori infection has been reported to increase the risk for development of gastric cancer (GC). We investigated whether long-term administration of PPI affects ectopic and metachronous recurrence of GC after endoscopic treatment.Methods: Participants were 687 patients who underwent endoscopic treatment for GC from January 2005 to March 2018. Questionnaire surveys and medical record reviews of medications, including PPIs, H2 receptor antagonists and low-dose aspirin (LDA) were conducted for all patients. The influence of PPI in ectopic and metachronous recurrence of GC was evaluated with Cox's proportional hazard analysis.Results: Patients who did not respond to the questionnaire and those who underwent additional treatment after endoscopic treatment were excluded from analyses; 418 patients were included. During an average observation period of 1608 days (range, 375-4993 days), 136 patients (32.5%) took PPIs for more than 1 year and 94 took PPIs for more than 3 years; of those, 40 had ectopic and metachronous recurrences. Cox's proportional hazards analysis revealed that long-term use of PPIs (for both 1 year and 3 years) was not a risk factor for recurrence. In addition, age, severity of gastric atrophy, long-term use of LDA, current infection with H. pylori, and cure achieved with the first endoscopic treatment were also not risk factors for recurrence.Conclusions: Long-term use of PPIs does not affect ectopic and metachronous recurrence of GC after endoscopic treatment.

Background: The present study aimed to evaluate the efficacy of linked color imaging (LCI) in diagnosing Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC). Methods: A total of 112 and 12 consecutive patients with BE and EAC were analyzed. The visibility scores of BE and EAC ranging from 4 (excellent visibility) to 0 (not detectable) were evaluated by three trainees and three experts using white light imaging (WLI), LCI mode, and blue laser imaging bright (BLI-b) mode. In addition, L∗a∗b∗ color values and color differences (ΔE∗) were evaluated using the CIELAB color space system. Results: The visibility score of the BE in LCI mode (2.94 ± 1.32) was significantly higher than those in WLI (2.46 ± 1.48) and BLI-b mode (2.35 ± 1.46) (p < 0.01). The color difference (ΔE∗) from the adjacent gastric mucosa in LCI mode (17.11 ± 8.53) was significantly higher than those in other modes (12.52 ± 9.37 in WLI and 11.96 ± 6.59 in BLI-b mode, p < 0.01). The visibility scores of EAC in LCI mode (2.56 ± 1.47) and BLI-b mode (2.51 ± 1.28) were significantly higher than that in WLI (1.64 ± 1.46) (p < 0.01). The color difference (ΔE∗) from the adjacent normal Barrett's mucosa in LCI mode (19.96 ± 7.97) was significantly higher than that in WLI (12.95 ± 11.86) (p = 0.03). Conclusion: The present findings suggest that LCI increases the visibility of BE and EAC and contributes to the improvement of the detection of these lesions.

BACKGROUND AND AIM: Cold snare polypectomy (CSP) is a safe treatment for colorectal adenomas. However, the R0 resection rate is not sufficiently high because of inadequate resection of muscularis mucosa. We hypothesized that CSP in an underwater environment could improve this procedure by helping to safely achieve resection containing the muscularis mucosa. We have named this procedure underwater cold snare polypectomy (UCSP). We aimed to investigate the efficacy and safety of UCSP for colorectal adenomas. METHODS: Between May 2017 and April 2018, patients diagnosed with colorectal adenomas <9 mm underwent UCSP. After follow-up colonoscopy 3 weeks later, the patients post-UCSP scars were biopsied. Outcomes were compared with those of a historical control group who underwent conventional CSP in our previous study using propensity score-matching methods. RESULTS: Overall, 224 lesions in 65 patients were prospectively resected by UCSP. Pathologically, 209 lesions were adenomas (4.5 ± 1.5 mm) including one intramucosal carcinoma. Only one pathological residual adenoma was identified, but there was no significant difference in the residual rate between the UCSP and CSP groups (both 1.0%). No complications were observed. R0 resection rate and rate of area containing the muscularis mucosa in the UCSP group were significantly higher than those in the CSP group (80.2% vs 32.7%, P < 0.001; 50.0% vs 35.3%, P = 0.015). CONCLUSION: Underwater cold snare polypectomy for diminutive and small colorectal adenomas was safe and effective from the perspective of pathological complete resection, which is likely facilitated by achieving an adequate depth of resection.

Epstein-Barr virus (EBV)-positive mucocutaneous ulcer is a B-cell lymphoproliferative disorder occurring in elderly or iatrogenic immunocompromised patients. We report a 27-year-old male patient with Crohn's disease (CD) who developed immunomodulator-associated lymphoproliferative disorder. The patient was diagnosed with CD at the age of 17 and was treated with maintenance therapy including high-dose infliximab and azathioprine. When he was admitted to our hospital with a diagnosis of intestinal obstruction, his abdominal computed tomography findings showed not only colonic wall thickening and narrowing of the descending colon but also multiple liver tumor lesions. His ileus symptom improved with conservative therapy, and a pathological evaluation of the tissue biopsy specimens from the descending colon and liver lesions indicated a morphological diagnosis of EBV-positive diffuse large B-cell lymphoma. This was a case of iatrogenic immunodeficiency-associated lymphoproliferative disorder due to an immunomodulator. The treatment was initiated with chemotherapy, but he died of disease progression 10 months after the diagnosis of lymphoma. Although cases of lymphoproliferative disorder due to treatment modalities used for CD are rare in Japan, an increase in the risk of lymphoproliferative diseases should be considered in patients with CD treated with immunomodulatory agents.

BACKGROUND AND AIM: Venous thromboembolism (VTE) is a common complication of inflammatory bowel disease (IBD). The aim of the present study was to identify predictors of VTE in hospitalized patients with IBD. METHODS: Patients with IBD who were hospitalized from February 2015 to March 2016 at the Chiba University Hospital were included. VTE was detected using enhanced computed tomography, and VTE onset within 2 months after admission was assessed. Predictors of VTE onset were investigated with clinical factors during hospitalization. Availability of the Caprini risk assessment model and Padua prediction score at the time of admission was also assessed. RESULTS: Seventy-two patients with IBD were hospitalized, and central venous catheters were placed in 43 of the 72 patients. During the observation period, VTE occurred in six patients (8.3%); however, none died as a result of the condition. Cox proportional hazards regression analysis identified D-dimer values on admission as a risk factor that was highly associated with VTE onset (hazard ratio = 1.590; 95% confidence interval, 1.132-2.233; P = 0.007) and significantly predicted the occurrence of VTE using the receiver operating characteristic curve (P = 0.005, area under the curve = 0.893). However, Caprini risk assessment model and Padua prediction scores were not useful tools for predicting VTE onset in patients with IBD. CONCLUSION: In hospitalized patients with IBD, D-dimer values were highly associated with VTE onset. Therefore, measurement of D-dimer values on admission is critical for the management of thromboembolic complications in patients with IBD.

AIMS: We evaluated the long-term prognosis of patients with obscure gastrointestinal bleeding (OGIB) who underwent capsule endoscopy (CE). METHODS: In our hospital, 429 patients underwent CE between November 2007 and March 2012. Among them, 259 patients underwent CE as the first examination for OGIB and were then followed at 77 clinics and hospitals. The clinical characteristics were investigated, including age, gender, overt/occult bleeding, the use of antithrombotic drugs and NSAIDs, complications (liver cirrhosis and hemodialysis), and CE. We asked the medical institutions for their survival data as of August 2017 (> 5 years after CE). RESULTS: The prognoses of 240 patients (92.6%) were analyzed. The average follow-up period was 55.7 (1-115) months. During the follow-up period, 57 patients (23.8%) died and the survival rates were 90.5% at 1 year, 81.7% at 3 years, and 74.7% at 5 years. Age 65 years or older and liver cirrhosis were predictive factors for a poor prognosis. Rebleeding occurred in 42 patients (17.9%) and small bowel cancer and gastrointestinal stromal tumor were found at 12 and 21 months after CE, respectively. CONCLUSIONS: Patients with OGIB showed a poor prognosis, especially those who were elderly or who had liver cirrhosis.

Introduction: Endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) is well accepted. However, its adaptation for elderly patients is unclear. This study aimed to investigate the prognosis and long-term outcomes of ESD for EGC in elderly patients aged ≥80 years by comparing their findings to the findings of patients aged <80 years. Materials and Methods: The study included 533 patients (632 lesions). The patients were divided into an elderly group (age, ≥80 years; 108 patients; 128 lesions; mean age, 83.4 ± 2.7 years) and a nonelderly group (age, <80 years; 425 patients; 504 lesions; mean age, 69.6 ± 7.9 years). We compared patient and lesion characteristics, overall survival (OS), and disease-specific survival (DSS) between the 2 groups retrospectively. Multivariate analysis was performed to clarify the risk factors of death after ESD. Results: The rate of curative resection and adverse events was not significantly different between the groups. The mean survival time periods with regard to OS/DSS in the elderly and nonelderly groups were 75.8 ± 5.9 and 122.8 ± 2.6 months (P < 0.05)/120.0 ± 3.0 and 136.4 ± 0.6 months (not significant), respectively. In the elderly group, eGFR <30 ml/min/1.73 m2 was an independent risk factor of death (hazard ratio = 5.32; 95% confidence interval = 1.39-20.5; P=0.015). Conclusion: ESD for EGC can be performed safely and can achieve high curability with good prognosis in elderly patients aged ≥80 years. After ESD, close attention should be paid to elderly patients with severe chronic kidney disease.

BACKGROUND: The clinical course of ulcerative colitis (UC) is characterized by repeated episodes of relapse and remission. We hypothesized that biomarkers that help distinguish refractory UC patients who are in remission using strong anti-immunotherapy could contribute in preventing the overuse of corticosteroids for treatment. Here, we clarified novel autoantibodies for UC patients in remission as clinical indicators to distinguish between refractory and non-refractory UC. METHODS: Antigen proteins recognized by serum antibodies of patients with UC in remission were screened using the protein array method. To validate the results, AlphaLISA was used to analyze the serum antibody titers with candidate protein antigens. Serum samples from 101 healthy controls, 121 patients with UC, and 39 patients with Crohn's disease were analyzed. RESULTS: Of 66 candidate protein antigens screened by ProtoArray™, six were selected for this study. The serum titers of anti-poly ADP-ribose glycohydrolase (PARG), anti-transcription elongation factor A protein-like 1, and anti-proline-rich 13 (PRR13) antibodies were significantly higher in patients with UC than in healthy controls. Anti-PARG and anti-PRR13 antibody titers were significantly higher in patients with refractory UC than in patients with non-refractory UC. There were no significant differences in any antibody titer between the active and remission phases. CONCLUSIONS: The serum titers of anti-PARG, anti-transcription elongation factor A protein-like 1, and anti-PRR13 antibodies were elevated in patients with UC. Anti-PARG and anti-PRR13 antibody titers may be novel clinical indicators for detecting refractory UC in patients in remission.

Background and study aims  Endoscopic submucosal dissection (ESD) requires advanced skills to perform safely without complications. The current study evaluated the usefulness of a novel three-dimensional (3D) imaging system in ESD using porcine stomachs. Methods  Four endoscopists (two trainees and two experts) performed eight ESD procedures using both 3D and 2D images. The usefulness of 3D image versus 2D image was evaluated by visibility and procedure time. In addition, occurrence of eyestrain and dizziness in 3D image was assessed. Results  En bloc resection was successfully achieved, without perforation, in all cases. The evaluation score in the 3D image group was better than that in the 2D image group, particularly depth perception was statistically significantly good. No significant difference was found in the working speed between the 2D and 3D image groups. Two examiners experienced eyestrain and dizziness while using the 3D image. Conclusions  All the ESD procedures were performed safely. Depth perception using the 3D image was better than with the 2D image. A novel 3D image system may facilitate ESD.

Background: There are known associations between inflammatory bowel disease (IBD) and changes in mucosal paracellular permeability. We recently developed a novel catheter that can measure mucosal admittance (MA). Methods: Patients with ulcerative colitis (UC) in clinical remission underwent real-time MA measurement during colonoscopy between June 2014 and July 2015 and were prospectively followed. MA measures were taken from normal-appearing mucosa using the Tissue Conductance Meter (TCM). We examined relationships between mucosal admittance, clinical parameters at the time of MA measurement, and disease relapse during the follow-up period using the Cox proportional hazards model. Results: We measured baseline MA in 54 patients with UC during remission, with no complications. Of these, 23 patients relapsed during the subsequent follow-up period, at a median of 25.8 ± 7.6 months. Rectal MA was the only predictor of disease relapse in multivariate analysis (P = 0.027). The optimal rectal MA cutoff value for relapse was 781.0 (area under the receiver operating characteristic curve, 0.712), and in patients who showed lower than normal cutoff values, there was a significantly higher likelihood of relapse compared with other patients (log-rank test, P < 0.001). Conclusions: High rectal MA measured by TCM is associated with long-term sustained remission. Real-time rectal MA measurement using a novel endoscopy-guided catheter could be a safe and useful means of predicting prognosis for patients with UC in remission.

BACKGROUND: Endoscopic resection of all colonic adenomas prevents the occurrence of colon cancer and death. The European Society of Gastrointestinal Endoscopy Clinical Guideline recommends resection of all polyps predicted to be adenomas and cold snare polypectomy (CSP) for removal of adenomas ≤ 9 mm on the basis of safety; however, it also states that this recommendation lacks adequate evidence of efficacy. The residual adenoma rate after resection is an important indicator of efficacy, but there have been no reports showing this prospectively. Therefore, we aimed to investigate the residual adenoma rate after CSP of small colonic polyps. METHODS: Between March 2015 and April 2017, patients who were endoscopically diagnosed with colorectal adenomas < 9 mm underwent CSP, the site being marked with endoscopic clips. Patients with pathologically confirmed adenomas underwent follow-up colonoscopy 3 weeks after CSP and any post-CSP scars were biopsied. The primary endpoint was the presence of pathological residual adenoma 3 weeks after CSP. RESULTS: Overall, 126 lesions in 39 patients were removed and 125 (99.2 %) were resected en bloc using CSP. Pathologically, 111 lesions (88.1 %) were confirmed as adenomas (4.2 ± 1.5 mm), with 36 of these (32.4 %) determined to be R0 resections. No complications were observed. All 37 patients with pathologically confirmed adenomas underwent follow-up colonoscopy, and 102 of 111 scars were detected in 33 patients. One pathological residual adenoma (0.98 %, 95 % confidence interval 0.02 % - 5.3 %) was identified. CONCLUSIONS: CSP appears to be an effective treatment for diminutive and small colorectal adenomas, with a low residual adenoma rate.

Background/Aims: Eosinophilic esophagitis (EoE) is often erroneously diagnosed as gastroesophageal reflux disease (GERD). The aim of this study is to investigate the prevalence of EoE and the expression of tight junction (TJ) proteins in patients with GERD symptoms. Methods: One hundred patients with GERD symptoms and 10 healthy controls were prospectively studied. Sixty-two patients had symptoms refractory to proton pump inhibitors (PPI). All patients underwent esophageal biopsy. Patients were diagnosed with EoE if the number of eosinophil granulocytes per high-power field was ≥15. Immunohistochemical analysis of TJ proteins (claudin-1, claudin-4, occludin, and zonula occludin-1 [ZO-1]) was performed. Results: EoE was diagnosed in six of 100 patients (6%) with GERD symptoms and in six patients (9.7%) of 62 patients with PPI-refractory GERD. Only one had typical EoE endoscopic findings. The proportion of ZO-1-positive cells was significantly lower in the lower than in the middle esophagus (56.0%±14.0% vs 66.0%±11.5%, p＜0.05). There were no significant correlations between TJ protein expression and GERD symptoms. Conclusions: The prevalence of EoE among patients with PPI-refractory GERD is approximately 10%. Regardless of endoscopic findings, esophageal biopsy is crucial in diagnosing EoE. The disruption of ZO-1 expression in the lower esophagus is significantly associated with GERD symptoms.

BACKGROUND: Impaired esophageal mucosal integrity plays a role in causing symptoms of gastroesophageal reflux disease (GERD). Recently, the assessment of esophageal baseline impedance (BI) using the multichannel intraluminal impedance-pH (MII-pH) test was suggested as a surrogate technique for the study of esophageal mucosal integrity and was reported to be useful in distinguishing GERD from non-GERD. However, measuring BI requires a 24-h testing period, is complicated, and causes considerable patient discomfort. SUMMARY: Recently, endoscopy-guided catheters that can measure mucosal impedance (MI) and mucosal admittance (MA), which is the inverse of impedance, were developed, and their usefulness in measuring MI and MA for the diagnosis of GERD has been reported. In these studies, esophageal MI values were significantly lower in patients with GERD than in those without GERD. In contrast, esophageal MA was significantly higher in patients with GERD than in those without. Furthermore, we reported that MA is inversely correlated with BI and correlated with acid exposure time. Key Messages: Endoscopy-guided real-time measurement of MI and MA may allow the estimation of mucosal integrity and may be a useful diagnostic tool for patients with GERD in a manner similar to 24-h MII-pH monitoring.

BACKGROUND/AIMS: Endoscopic balloon dilatation (EBD) is an alternative to surgery for strictures in patients with Crohn's disease (CD). The aim of the present study was to clarify the efficacy and safety of EBD for strictures in patients with CD. METHODS: Twenty-six patients with CD who underwent EBD for strictures from August 2008 to November 2015 were followed up after dilatation. Short-term success was defined as the disappearance of obstructive symptoms after technically adequate dilatation was achieved. The short-term success rate of EBD, safety profile of EBD, and cumulative surgery-free and redilatation-free rates were analyzed. RESULTS: Sixty-five EBDs were performed for CD patients in the follow-up period. The short-term success rate was 100% (26/26), and no complications were encountered during this study. Two (7.7%) patients underwent surgery during the observation period. The cumulative surgery-free rate after the initial EBD was 90.3% at both 2 and 3 years. The cumulative redilatation-free rate after the initial EBD was 52.1% at 2 years and 39.1% at 3 years. CONCLUSION: EBD for strictures secondary to CD provides not only short-term success but also long-term efficacy. Although a high redilatation rate is one of the clinical problems of this procedure, EBD is an effective therapy for avoiding intestinal recession in CD -stricture.

BACKGROUND: In Western countries, most patients with primary sclerosing cholangitis (PSC) have concurrent ulcerative colitis (UC). The number of patients with UC in East Asia has increased markedly over the past two decades. However, current clinical features of PSC and of PSC associated with UC (PSC-UC) have not yet been clarified in East Asia, particularly in Japan. We aimed to reveal the clinical courses and associations with UC in Japanese patients with PSC from the mutual viewpoint of PSC and UC. METHODS: We retrospectively retrieved medical records of patients with PSC (69) and UC (1242) who were diagnosed at Chiba University Hospital between June 1991 and August 2017. RESULTS: In the present cohort, 37 patients had PSC-UC; the cumulative risks of PSC in patients with UC and of UC in patients with PSC were 3.0% and 53.6%, respectively. We confirmed similar distinctive results by a Japanese nationwide survey, noting that younger patients with PSC had a notably high possibility of association with UC. From the viewpoint of the UC cohort, the occurrence of right-sided disease was significantly higher in patients with PSC-UC than in those with UC (16.2% vs. 4.2%, P = 0.003). Pancolitis was more commonly observed in PSC-UC, and proctits/left-sided colitis was less commonly found in patients with UC. The number of patients with young-onset PSC-UC may be increasing similar to an increase in patients with UC in Japan. CONCLUSIONS: In our cohort, the comorbidity rate of PSC-UC was higher than that obtained in previous reports. The incidence of PSC-UC and UC may increase in the future in East Asia, particularly in Japan.

OBJECTIVES: A novel catheter that can measure mucosal admittance (MA), the inverse of impedance, was developed recently. In this pilot study, we aimed to clarify the usefulness of measuring MA for diagnosing gastroesophageal reflux disease (GERD). METHODS: We conducted two prospective studies. In the first study, esophageal MA was evaluated in 120 participants (24 with erosive esophagitis, 82 with heartburn but non-erosive esophagitis, and 14 healthy volunteers) and compared with the endoscopic findings. In the second study, multichannel intraluminal impedance combined with pH (MII-pH) tests was conducted followed by an MA measurement in 33 patients with non-erosive esophagitis and proton pump inhibitor (PPI)-refractory heartburn. Based on the MII-pH test results, patients were divided into GERD or functional heartburn (FH). MA was compared between the GERD and FH groups and also compared with the baseline impedance (BI) and acid exposure time (AET). RESULTS: Median MA at the distal esophagus was significantly higher in patients with erosive esophagitis compared with that in patients with non-erosive esophagitis and healthy volunteers (46.8, 13.1 and 6.5, respectively, P<0.01). In patients with PPI-refractory heartburn, the median MA at the distal esophagus was significantly higher in patients with GERD than those with FH (19.3 vs. 7.2, P<0.05). There was a negative correlation between MA and BI, and a positive correlation between MA and AET at the distal esophagus (r=-0.46 and r=0.53, P<0.05). CONCLUSIONS: Real-time measurement of MA is useful to distinguish GERD from non-GERD.

OBJECTIVES: The pathophysiology of functional dyspepsia (FD) is not fully understood. Impaired duodenal mucosal integrity characterized by increased mucosal permeability and/or low-grade inflammation was reported as potentially important etiologies. We aimed to determine the utility of a recently developed simple catheterization method to measure mucosal admittance (MA), the inverse of mucosal impedance, for evaluation of duodenal mucosal permeability in patients with FD. METHODS: We conducted two prospective studies. In the first study, duodenal MA of 23 subjects was determined by catheterization during upper endoscopy, and transepithelial electrical resistance (TEER) of duodenal biopsy samples in Ussing chambers was measured to assess the correlation between MA and TEER. In the second study, duodenal MA of 21 patients with FD fulfilling the Rome III criteria was compared with that of 23 healthy subjects. RESULTS: The mean MA and TEER values were 367.5±134.7 and 24.5±3.7 Ω cm2, respectively. There was a significant negative correlation between MA and TEER (r=-0.67, P=0.0004, Pearson's correlation coefficient). The mean MA in patients with FD was significantly higher than that in healthy subjects (455.7±137.3 vs. 352.1±66.9, P=0.002, unpaired t-test). No procedure-related complications were present. CONCLUSIONS: We demonstrated the presence of increased duodenal mucosal permeability in patients with FD by MA measurement using a simple catheterization method during upper endoscopy.

BACKGROUND: Maintenance of mucosal healing is a primary goal when treating Crohn's disease (CD). Endoscopy is the most precise method for the assessment of mucosal healing, but is considered overly invasive for patients with CD. In contrast, CT enterography (CTE) is less invasive, but little is known about the correlation between mucosal status and CTE parameters. METHODS: We recruited CD patients who underwent CTE and double balloon endoscopy (DBE) on the same day at our hospital between 2012 and 2014. CTE parameters evaluated included bowel-wall thickening, mural hyperenhancement, mural stratification (target sign), submucosal fat deposition, mesenteric hypervascularity (comb sign), increased fat density, mesenteric fibrofatty proliferation, enlarged mesenteric lymph nodes, and stenosis/sacculation. Endoscopic findings were evaluated using the Simple Endoscopic Score for Crohn's Disease (SES-CD). CTE parameters that were predictive of higher values in the SES-CD were extracted statistically. RESULTS: Forty-one patients were recruited, from which 191 intestinal segments were evaluated. Spearman's rank correlation coefficients showed that the majority of CTE values exhibited mild to moderate correlations with SES-CD values. Notably, multiple ordinal logistic regression analysis demonstrated that CTE findings obtained from the mesenteric area, such as mesenteric hypervascularity (comb sign) and enlarged mesenteric lymph nodes, were more critical predictors of endoscopic mucosal ulceration than those obtained from the bowel wall. CONCLUSIONS: This study was the first of its kind to assess correlations between CTE values and SES-CD values. Mesenteric findings of CTE, rather than mural findings, were highly correlated with the endoscopically evaluated severity of ulceration.

BACKGROUND AND AIM: Evidence regarding safety and efficacy of heparin-bridging therapy for colonoscopic polypectomy remains scarce. The aim of the present study was to evaluate the risk of post-polypectomy bleeding (PPB) in patients receiving heparin-bridging therapy. METHODS: We retrospectively reviewed the database of patients who underwent colonoscopic polypectomy with prophylactic clip closure between January 2007 and December 2014 at our institution. We evaluated patients receiving heparin-bridging therapy (HB group) compared with those who did not receive antithrombotic therapy (No-HB group). RESULTS: A total of 1421 polypectomies were carried out on 773 patients; 45 patients were in the HB group and 728 patients were in the No-HB group. The incidence of PPB per patient was significantly higher in the HB group (22.2% vs 1.9%, P < 0.0001), and multivariate analysis showed that heparin-bridging therapy was an independent risk factor for PPB (OR 9.80, 95% CI 4.23-22.3, P < 0.0001). In the HB group, the polyp size was not a risk factor for PPB (OR 0.67, 95% CI 0.19-2.26, P = 0.55); the incidence of PPB in lesions of <10 mm and ≥10 mm in size was 14.6% and 10.2% respectively. In contrast, that was a significant risk factor in the No-HB group (OR 4.71, 95% CI 1.41-21.3, P = 0.011). Activated partial thromboplastin time and international normalized ratio were in or under the therapeutic range in the HB group when PPB occurred. CONCLUSIONS: Heparin-bridging therapy is associated with a high risk of PPB regardless of polyp size.

BACKGROUND AND AIM: Proton pump inhibitors (PPI) are effective at healing artificial ulcers after endoscopic submucosal dissection (ESD) for gastric neoplasms; however, the efficacy of vonoprazan is not completely understood. The aim of the present study was to determine the healing effect of vonoprazan on artificial ulcers post-gastric ESD relative to PPI. METHODS: Thirty-five patients who underwent gastric ESD between April and November 2015 were treated with vonoprazan 20 mg/day for 4 weeks and subsequently underwent endoscopy for evaluation of ulcer size (V group). Ulcer contraction rate was determined by the following formula: ([ESD specimen size] - [ulcer size at 4 weeks after ESD])/(ESD specimen size) × 100%. We compared the results with those of a historical control group treated with esomeprazole 20 mg/day for 4 weeks after gastric ESD and subsequently measured their ulcer size (33 patients, E group) by propensity score-matching methods. RESULTS: Sixty-two subjects were enrolled after propensity score-matching. Ulcer contraction rate at 4 weeks after ESD in the V group was significantly higher than that of the E group (97.7 ± 3.2% vs 94.5 ± 6.7%, respectively, P = 0.025). Number of subjects with a scar-stage ulcer (100% contraction rate) tended to be higher in the V group relative to the E group (32% [10 of 31] vs 13% [4 of 31], respectively, P = 0.070, McNemar's chi-squared test). CONCLUSION: Vonoprazan has a faster post-gastric ESD artificial ulcer contraction rate than esomeprazole. Vonoprazan may supersede PPI in treating post-ESD artificial ulcers of the stomach.

BACKGROUND/AIMS: Ineffective esophageal motility (IEM) is the most common gastrointestinal motility disorder. Studies have reported that IEM is related to gastroesophageal reflux disease (GERD). However, the relationship between IEM and GERD remains uncertain. This study aims to clarify this relationship retrospectively. METHODS: We analyzed 195 subjects who underwent high-resolution manometry between January 2011 and September 2016. Of these subjects, 72 had normal esophageal motility (NEM) and 26 had IEM. We investigated differences in the clinical characteristics, severity and duration of GERD symptoms, and comorbid extra-esophageal symptoms of the subjects. Comorbid extra-esophageal symptoms were assessed with the Gastrointestinal Symptom Rating Scale questionnaire. Investigation-defined GERD was diagnosed when erosive esophagitis or abnormal multichannel intraluminal impedance was present. RESULTS: We found no significant difference in the prevalence of IEM between patients with and without GERD (37.5 and 21.1%, respectively; p = 0.174). There were no differences in age, gender, body mass index, presence of hiatal hernia, or duration of GERD between the groups. Compared to patients with NEM, those with IEM were significantly less likely to have comorbid extra-esophageal symptoms (p < 0.05). CONCLUSION: There is no association between IEM and GERD.

Here we report three cases in which the cellophane wall of the PillCam® patency capsule (tag-less PC), lacking a radio frequency identification tag, was retained. Case 1 A 33-year-old man with Crohn's disease (CD) who was administered the tag-less PC, subsequently underwent resection for perforated colon. We recovered the cellophane wall that could perforate the intestine and cause peritonitis. Case 2 A 34-year-old man with a recurring intestinal obstruction of unknown cause was administered the tag-less PC test. Computed tomography (CT) detected the cellophane wall at the oral side of an ileal stenosis. He was subsequently diagnosed with CD. Case 3 A 60-year-old woman with recurrent diarrhea was examined using CT, which revealed a thickened ileal wall. She was administered the tag-less PC test. CT detected the cellophane wall at the oral side of an ileal stenosis. Double-balloon enteroscopy revealed that the stenosis was caused by a malignant lymphoma, and the cellophane wall was simultaneously removed. Although there are numerous studies that report the usefulness and safety of tag-less PCs, few studies mention entrapment of the cellophane wall. Our present report indicated that tag-less PCs may cause such adverse effects and illustrated the usefulness of CT for detecting the trapped cellophane wall.

OBJECTIVES: Previous studies have shown that water exchange is superior to air insufflation in attenuating insertion pain during colonoscopy. We conducted a randomized controlled trial with head-to-head comparison of these methods to assess their effectiveness in colonoscopy without sedation. METHODS: A total of 447 outpatients were randomized to either water exchange (WE) or the standard air (CO2) insufflation (AI). The primary outcome was the improvement of patient intraprocedural pain (pain score), evaluated using a questionnaire (scores 1 to 5). RESULTS: After exclusion of 44 patients from further analysis, 403 patients were analyzed. There was no difference in clinical background between the WE and AI groups. Patients in the WE group reported less intraprocedural pain than those in the AI group (2.17 ± 1.06 vs. 2.42 ± 1.03; unpaired t test, p = 0.021). We divided the cases into two groups, more or less painful colonoscopy, based on age, body mass index, use of anti-peristaltic drugs or not, and physician's experience. In less painful colonoscopy, the WE method could reduce pain effectively but its effect was limited in the more painful group. CONCLUSION: WE is superior to AI for attenuating insertion pain during colonoscopy without sedation, but its efficacy is limited in more painful endoscopy.