Solution structure of the HOIL-1L NZF domain reveals a conformational switch regulating linear ubiquitin affinity.

Attachment of polyubiquitin (poly-Ub) chains to proteins is a major posttranslational modification in eukaryotes. Linear ubiquitin chain assembly complex, consisting of HOIP (HOIL-1-interacting protein), HOIL-1L (heme-oxidized IRP2 Ub ligase 1), and SHARPIN (Shank-associated RH domain-interacting protein), specifically synthesizes "head-to-tail" poly-Ub chains, which are linked via the N-terminal methionine α-amino and C-terminal carboxylate of adjacent Ub units and are thus commonly called "linear" poly-Ub chains. Linear ubiquitin chain assembly complex-assembled linear poly-Ub chains play key roles in immune signaling and suppression of cell death and have been associated with immune diseases and cancer; HOIL-1L is one of the proteins known to selectively bind linear poly-Ub via its Npl4 zinc finger (NZF) domain. Although the structure of the bound form of the HOIL-1L NZF domain with linear di-Ub is known, several aspects of the recognition specificity remain unexplained. Here, we show using NMR and orthogonal biophysical methods, how the NZF domain evolves from a free to the specific linear di-Ub-bound state while rejecting other potential Ub species after weak initial binding. The solution structure of the free NZF domain revealed changes in conformational stability upon linear Ub binding, and interactions between the NZF core and tail revealed conserved electrostatic contacts, which were sensitive to charge modulation at a reported phosphorylation site: threonine-207. Phosphomimetic mutations reduced linear Ub affinity by weakening the integrity of the linear di-Ub-bound conformation. The described molecular determinants of linear di-Ub binding provide insight into the dynamic aspects of the Ub code and the NZF domain's role in full-length HOIL-1L.

High risk stigmata and treatment strategy for acute lower gastrointestinal bleeding: a nationwide study in Japan.

BACKGROUND: The rebleeding risks and outcomes of endoscopic treatment for acute lower gastrointestinal bleeding (ALGIB) may differ depending on the bleeding location, type, and etiology of stigmata of recent hemorrhage (SRH) but have yet to be fully investigated. We aimed to identify high risk endoscopic SRH and to propose an optimal endoscopic treatment strategy. METHODS: We retrospectively analyzed 2699 ALGIB patients with SRH at 49 hospitals (CODE BLUE-J Study), of whom 88.6 % received endoscopic treatment. RESULTS: 30-day rebleeding rates of untreated SRH significantly differed among locations (left colon 15.5 % vs. right colon 28.6 %) and etiologies (diverticular bleeding 27.5 % vs. others [e. g. ulcerative lesions or angioectasia] 8.9 %), but not among bleeding types. Endoscopic treatment reduced the overall rebleeding rate (adjusted odds ratio [AOR] 0.69; 95 %CI 0.49-0.98), and the treatment effect was significant in right-colon SRH (AOR 0.46; 95 %CI 0.29-0.72) but not in left-colon SRH. The effect was observed in both active and nonactive types, but was not statistically significant. Moreover, the effect was significant for diverticular bleeding (AOR 0.60; 95 %CI 0.41-0.88) but not for other diseases. When focusing on treatment type, the effectiveness was not significantly different between clipping and other modalities for most SRH, whereas ligation was significantly more effective than clipping in right-colon diverticular bleeding. CONCLUSIONS: A population-level endoscopy dataset allowed us to identify high risk endoscopic SRH and propose a simple endoscopic treatment strategy for ALGIB. Unlike upper gastrointestinal bleeding, the rebleeding risks for ALGIB depend on colonic location, bleeding etiology, and treatment modality.

Long-term Risks of Recurrence After Hospital Discharge for Acute Lower Gastrointestinal Bleeding: A Large Nationwide Cohort Study.

BACKGROUND & AIMS: Currently, large, nationwide, long-term follow-up data on acute lower gastrointestinal bleeding (ALGIB) are scarce. We investigated long-term risks of recurrence after hospital discharge for ALGIB using a large multicenter dataset. METHODS: We retrospectively analyzed 5048 patients who were urgently hospitalized for ALGIB at 49 hospitals across Japan (CODE BLUE-J study). Risk factors for the long-term recurrence of ALGIB were analyzed by using competing risk analysis, treating death without rebleeding as a competing risk. RESULTS: Rebleeding occurred in 1304 patients (25.8%) during a mean follow-up period of 31 months. The cumulative incidences of rebleeding at 1 and 5 years were 15.1% and 25.1%, respectively. The mortality risk was significantly higher in patients with out-of-hospital rebleeding episodes than in those without (hazard ratio, 1.42). Of the 30 factors, multivariate analysis showed that shock index ≥1 (subdistribution hazard ratio [SHR], 1.25), blood transfusion (SHR, 1.26), in-hospital rebleeding (SHR, 1.26), colonic diverticular bleeding (SHR, 2.38), and thienopyridine use (SHR, 1.24) were significantly associated with increased rebleeding risk. Multivariate analysis of colonic diverticular bleeding patients showed that blood transfusion (SHR, 1.20), in-hospital rebleeding (SHR, 1.30), and thienopyridine use (SHR, 1.32) were significantly associated with increased rebleeding risk, whereas endoscopic hemostasis (SHR, 0.83) significantly decreased the risk. CONCLUSIONS: These large, nationwide follow-up data highlighted the importance of endoscopic diagnosis and treatment during hospitalization and the assessment of the need for ongoing thienopyridine use to reduce the risk of out-of-hospital rebleeding. This information also aids in the identification of patients at high risk of rebleeding.

Outcomes and recurrent bleeding risks of detachable snare and band ligation for colonic diverticular bleeding: a multicenter retrospective cohort study.

BACKGROUND AND AIMS: Ligation therapy, including endoscopic detachable snare ligation (EDSL) and endoscopic band ligation (EBL), has emerged as an endoscopic treatment for colonic diverticular bleeding (CDB); its comparative effectiveness and risk of recurrent bleeding remain unclear, however. Our goal was to compare the outcomes of EDSL and EBL in treating CDB and identify risk factors for recurrent bleeding after ligation therapy. METHODS: We reviewed data of 518 patients with CDB who underwent EDSL (n = 77) or EBL (n = 441) in a multicenter cohort study named the Colonic Diverticular Bleeding Leaders Update Evidence From Multicenter Japanese Study (CODE BLUE-J Study). Outcomes were compared by using propensity score matching. Logistic and Cox regression analyses were performed for recurrent bleeding risk, and a competing risk analysis was used to treat death without recurrent bleeding as a competing risk. RESULTS: No significant differences were found between the 2 groups in terms of initial hemostasis, 30-day recurrent bleeding, interventional radiology or surgery requirements, 30-day mortality, blood transfusion volume, length of hospital stay, and adverse events. Sigmoid colon involvement was an independent risk factor for 30-day recurrent bleeding (odds ratio, 1.87; 95% confidence interval, 1.02-3.40; P = .042). History of acute lower GI bleeding (ALGIB) was a significant long-term recurrent bleeding risk factor on Cox regression analysis. A performance status score of 3/4 and history of ALGIB were long-term recurrent bleeding factors on competing risk regression analysis. CONCLUSIONS: There were no significant differences in outcomes between EDSL and EBL for CDB. After ligation therapy, careful follow-up is required, especially in the treatment of sigmoid diverticular bleeding during admission. History of ALGIB and performance status at admission are important risk factors for long-term recurrent bleeding after discharge.

Timing of colonoscopy in acute lower GI bleeding: a multicenter retrospective cohort study.

BACKGROUND AND AIMS: We aimed to determine the optimal timing of colonoscopy and factors that benefit patients who undergo early colonoscopy for acute lower GI bleeding. METHODS: We identified 10,342 patients with acute hematochezia (CODE BLUE-J study) admitted to 49 hospitals in Japan. Of these, 6270 patients who underwent a colonoscopy within 120 hours were included in this study. The inverse probability of treatment weighting method was used to adjust for baseline characteristics among early (≤24 hours, n = 4133), elective (24-48 hours, n = 1137), and late (48-120 hours, n = 1000) colonoscopy. The average treatment effect was evaluated for outcomes. The primary outcome was 30-day rebleeding rate. RESULTS: The early group had a significantly higher rate of stigmata of recent hemorrhage (SRH) identification and a shorter length of stay than the elective and late groups. However, the 30-day rebleeding rate was significantly higher in the early group than in the elective and late groups. Interventional radiology (IVR) or surgery requirement and 30-day mortality did not significantly differ among groups. The interaction with heterogeneity of effects was observed between early and late colonoscopy and shock index (shock index <1, odds ratio [OR], 2.097; shock index ≥1, OR, 1.095; P for interaction = .038) and performance status (0-2, OR, 2.481; ≥3, OR, .458; P for interaction = .022) for 30-day rebleeding. Early colonoscopy had a significantly lower IVR or surgery requirement in the shock index ≥1 cohort (OR, .267; 95% confidence interval, .099-.721) compared with late colonoscopy. CONCLUSIONS: Early colonoscopy increased the rate of SRH identification and shortened the length of stay but involved an increased risk of rebleeding and did not improve mortality and IVR or surgery requirement. Early colonoscopy particularly benefited patients with a shock index ≥1 or performance status ≥3 at presentation.

Weekend Effect on Clinical Outcomes of Acute Lower Gastrointestinal Bleeding: A Large Multicenter Cohort Study in Japan.

INTRODUCTION: Weekend admissions showed increased mortality in several medical conditions. This study aimed to examine the weekend effect on acute lower gastrointestinal bleeding (ALGIB) and its mortality and other outcomes. METHODS: This retrospective cohort study (CODE BLUE-J Study) was conducted at 49 Japanese hospitals between January 2010 and December 2019. In total, 8,120 outpatients with acute hematochezia were enrolled and divided into weekend admissions and weekday admissions groups. Multiple imputation (MI) was used to handle missing values, followed by propensity score matching (PSM) to compare outcomes. The primary outcome was mortality; the secondary outcomes were rebleeding, length of stay (LOS), blood transfusion, thromboembolism, endoscopic treatment, the need for interventional radiology, and the need for surgery. Colonoscopy and computed tomography (CT) management were also evaluated. RESULTS: Before PSM, there was no significant difference in mortality (1.3% vs. 0.9%, p = 0.133) between weekend and weekday admissions. After PSM with MI, 1,976 cases were matched for each admission. Mortality was not significantly different for weekend admissions compared with weekday admissions (odds ratio [OR] 1.437, 95% confidence interval [CI] 0.785-2.630; p = 0.340). No significant difference was found with other secondary outcomes in weekend admissions except for blood transfusion (OR 1.239, 95% CI 1.084-1.417; p = 0.006). Weekend admission had a negative effect on early colonoscopy (OR 0.536, 95% CI 0.471-0.609; p < 0.001). Meanwhile, urgent CT remained significantly higher in weekend admissions (OR 1.466, 95% CI 1.295-1.660; p < 0.001). CONCLUSION: Weekend admissions decrease early colonoscopy and increase urgent CT but do not affect mortality or other outcomes except transfusion.

Early feeding reduces length of hospital stay in patients with acute lower gastrointestinal bleeding: A large multicentre cohort study.

AIM: No studies have compared the clinical outcomes of early and delayed feeding in patients with acute lower gastrointestinal bleeding (ALGIB). This study aimed to evaluate the benefits and risks of early feeding in a nationwide cohort of patients with ALGIB in whom haemostasis was achieved. METHODS: We reviewed data for 5910 patients with ALGIB in whom haemostasis was achieved and feeding was resumed within 3 days after colonoscopy at 49 hospitals across Japan (CODE BLUE-J Study). Patients were divided into an early feeding group (≤1 day, n = 3324) and a delayed feeding group (2-3 days, n = 2586). Clinical outcomes were compared between the groups by propensity matching analysis of 1508 pairs. RESULTS: There was no significant difference between the early and delayed feeding groups in the rebleeding rate within 7 days after colonoscopy (9.4% vs. 8.0%; p = 0.196) or in the rebleeding rate within 30 days (11.4% vs. 11.5%; p = 0.909). There was also no significant between-group difference in the need for interventional radiology or surgery or in mortality. However, the median length of hospital stay after colonoscopy was significantly shorter in the early feeding group (5 vs. 7 days; p < 0.001). These results were unchanged when subgroups of presumptive and definitive colonic diverticular bleeding were compared. CONCLUSION: The findings of this nationwide study suggest that early feeding after haemostasis can shorten the hospital stay in patients with ALGIB without increasing the risk of rebleeding.

LONG-HOSP Score: A Novel Predictive Score for Length of Hospital Stay in Acute Lower Gastrointestinal Bleeding - A Multicenter Nationwide Study.

INTRODUCTION: Length of stay (LOS) in hospital affects cost, patient quality of life, and hospital management; however, existing gastrointestinal bleeding models applicable at hospital admission have not focused on LOS. We aimed to construct a predictive model for LOS in acute lower gastrointestinal bleeding (ALGIB). METHODS: We retrospectively analyzed the records of 8,547 patients emergently hospitalized for ALGIB at 49 hospitals (the CODE BLUE-J Study). A predictive model for prolonged hospital stay was developed using the baseline characteristics of 7,107 patients and externally validated in 1,440 patients. Furthermore, a multivariate analysis assessed the impact of additional variables during hospitalization on LOS. RESULTS: Focusing on baseline characteristics, a predictive model for prolonged hospital stay was developed, the LONG-HOSP score, which consisted of low body mass index, laboratory data, old age, nondrinker status, nonsteroidal anti-inflammatory drug use, facility with ≥800 beds, heart rate, oral antithrombotic agent use, symptoms, systolic blood pressure, performance status, and past medical history. The score showed relatively high performance in predicting prolonged hospital stay and high hospitalization costs (area under the curve: 0.70 and 0.73 for derivation, respectively, and 0.66 and 0.71 for external validation, respectively). Next, we focused on in-hospital management. Diagnosis of colitis or colorectal cancer, rebleeding, and the need for blood transfusion, interventional radiology, and surgery prolonged LOS, regardless of the LONG-HOSP score. By contrast, early colonoscopy and endoscopic treatment shortened LOS. CONCLUSIONS: At hospital admission for ALGIB, our novel predictive model stratified patients by their risk of prolonged hospital stay. During hospitalization, early colonoscopy and endoscopic treatment shortened LOS.

Development and validation of a novel model for predicting stigmata of recent hemorrhage in acute lower gastrointestinal bleeding: Multicenter nationwide study.

OBJECTIVES: Stigmata of recent hemorrhage (SRH) directly indicate a need for endoscopic therapy in acute lower gastrointestinal bleeding (LGIB). Colonoscopy would be prioritized for patients with highly suspected SRH, but the predictors of colonic SRH remain unclear. We aimed to construct a predictive model for the efficient detection of SRH using a nationwide cohort. METHODS: We retrospectively analyzed 8360 patients admitted through hospital emergency departments for acute LGIB in the CODE BLUE-J Study (49 hospitals throughout Japan). All patients underwent inpatient colonoscopy. To develop an SRH predictive model, 4863 patients were analyzed. Baseline characteristics, colonoscopic factors (timing, preparation, and devices), and computed tomography (CT) extravasation were extensively assessed. The performance of the model was externally validated in 3497 patients. RESULTS: Colonic SRH was detected in 28% of patients. A novel predictive model for detecting SRH (CS-NEED score: ColonoScopic factors, No abdominal pain, Elevated PT-INR, Extravasation on CT, and DOAC use) showed high performance (area under the receiver operating characteristic curve [AUC] 0.74 for derivation and 0.73 for external validation). This score was also highly predictive of active bleeding (AUC 0.73 for derivation and 0.76 for external validation). Patients with low (0-6), intermediate (7-8), and high (9-12) scores in the external validation cohort had SRH identification rates of 20%, 31%, and 64%, respectively (P < 0.001 for trend). CONCLUSIONS: A novel predictive model for colonic SRH identification (CS-NEED score) can specify colonoscopies likely to achieve endoscopic therapy in acute LGIB. Using the model during initial management would contribute to finding and treating SRH efficiently.

Effectiveness of clip-and-thread traction-assisted duodenal endoscopic submucosal dissection: a propensity score-matched study (with video).

BACKGROUND AND AIMS: The indications for endoscopic submucosal dissection (ESD) in superficial nonampullary duodenal epithelial tumors (SNADETs) remain controversial because the procedure is technically challenging. Moreover, the effectiveness of clip-and-thread traction-assisted ESD (TA-ESD) for SNADETs has not been assessed. The aim of the current study was to compare the effectiveness of duodenal TA-ESD and conventional ESD for SNADETs. METHODS: SNADETs treated with conventional ESD or TA-ESD between April 2017 and March 2021 at Saitama Medical University International Medical Center were evaluated retrospectively. RESULTS: There were 49 cases of conventional ESD and 32 cases of TA-ESD for SNADETs. Using a propensity score-matched design, we selected 26 pairs of cases with conventional ESD and TA-ESD. In the unmatched cohort, patients treated with TA-ESD were characterized by a higher R0 (no tumor identified at the lateral or vertical margins) resection rate (P = .004), more frequent poor submucosal lifting because of fibrosis (P = .014), and shorter follow-up period (P = .0004) than patients treated with conventional ESD. In the propensity score-matched pairs, patients treated with TA-ESD were characterized by a higher rate of R0 resection (P = .021) and a shorter follow-up period (P = .0061). The findings regarding R0 resection rates were confirmed by multivariate logistic regression models, which found a higher odds ratio (OR) for R0 resection in patients who underwent TA-ESD than in patients who underwent conventional ESD both in the unmatched cohort (OR, 17.0; 95% confidence interval, 1.6-178.8; P = .018) and in the propensity score-matched pairs (OR, 26.7; 95% confidence interval, 1.5-460.2; P = .024). CONCLUSIONS: Our findings suggest TA-ESD may increase the rate of R0 resection in patients with SNADETs in comparison with conventional ESD.

Vonoprazan versus proton pump inhibitors for postendoscopic submucosal dissection bleeding in the stomach: a multicenter population-based comparative study.

BACKGROUND AND AIMS: The effectiveness of vonoprazan relative to that of proton pump inhibitors (PPIs) after gastric endoscopic submucosal dissection (ESD) is unclear. Although previous studies used post-ESD ulcer healing as the outcome measure, post-ESD bleeding rate is the most objective and appropriate outcome measure because it has less ascertainment bias. We aimed to compare the post-ESD bleeding rates between vonoprazan and PPIs. METHODS: This nationwide population-based retrospective cohort study was conducted between 2014 and 2018 and involved 9 hospitals. After 2 days of intravenous PPI administration, either vonoprazan or PPI was administrated from postoperative day 2 to 30. RESULTS: Overall, data of 1715 patients (627 patient pairs) were analyzed through propensity score matching. The vonoprazan group had significantly lower post-ESD bleeding rates than the PPI group (overall, 11.9% vs 17.2%, P = .008; bleeding between days 2 and 30, 7.8% vs 11.8%, P = .015). The readmission rate because of post-ESD bleeding was lower in the vonoprazan group (2.4% vs 4.1%, P = .081). Blood transfusion (2.1% vs 3.0%, P = .15) and additional surgery because of delayed perforation (.5% vs 1.0%, P = .32) were not significantly different between the 2 groups. No deaths within 30 days occurred in both groups. On Cox regression analysis, vonoprazan use, lesion location (antrum), aspirin use, direct oral anticoagulant use, and Charlson Comorbidity Index (≥2) were associated with an increased risk of post-ESD bleeding within 30 days. CONCLUSIONS: Vonoprazan has a lower post-ESD bleeding rate than PPIs. Further prospective studies are required to confirm these results.

Treatment strategies for reducing early and late recurrence of colonic diverticular bleeding based on stigmata of recent hemorrhage: a large multicenter study.

BACKGROUND AND AIMS: Treatment strategies for colonic diverticular bleeding (CDB) based on stigmata of recent hemorrhage (SRH) remain unstandardized, and no large studies have evaluated their effectiveness. We sought to identify the best strategy among combinations of SRH identification and endoscopic treatment strategies. METHODS: We retrospectively analyzed 5823 CDB patients who underwent colonoscopy at 49 hospitals throughout Japan (CODE-BLUE J-Study). Three strategies were compared: find SRH (definitive CDB) and treat endoscopically, find SRH (definitive CDB) and treat conservatively, and without finding SRH (presumptive CDB) treat conservatively. In conducting pairwise comparisons of outcomes in these groups, we used propensity score-matching analysis to balance baseline characteristics between the groups being compared. RESULTS: Both early and late recurrent bleeding rates were significantly lower in patients with definitive CDB treated endoscopically than in those with presumptive CDB treated conservatively (<30 days, 19.6% vs 26.0% [P < .001]; <365 days, 33.7% vs 41.6% [P < .001], respectively). In patients with definitive CDB, the early recurrent bleeding rate was significantly lower in those treated endoscopically than in those treated conservatively (17.4% vs 26.7% [P = .038] for a single test of hypothesis; however, correction for multiple testing of data removed this significance). The late recurrent bleeding rate was also lower, but not significantly, in those treated endoscopically (32.0% vs 36.1%, P = .426). Definitive CDB treated endoscopically showed significantly lower early and late recurrent bleeding rates than when treated conservatively in cases of SRH with active bleeding, nonactive bleeding, and in the right-sided colon but not left-sided colon. CONCLUSIONS: Treating definitive CDB endoscopically was most effective in reducing recurrent bleeding over the short and long term, compared with not treating definitive CDB or presumptive CDB. Physicians should endeavor to find and treat SRH for suspected CDB.

Effectiveness and adverse events of endoscopic clipping versus band ligation for colonic diverticular hemorrhage: a large-scale multicenter cohort study.

BACKGROUND : Prior studies have shown the effectiveness of both endoscopic band ligation (EBL) and clipping for colonic diverticular hemorrhage (CDH) but have been small and conducted at single centers. Therefore, we investigated which was the more effective and safe treatment in a multicenter long-term cohort study. METHODS : We reviewed data for 1679 patients with CDH who were treated with EBL (n = 638) or clipping (n = 1041) between January 2010 and December 2019 at 49 hospitals across Japan (CODE BLUE-J study). Logistic regression analysis was used to compare outcomes between the two treatments. RESULTS : In multivariate analysis, EBL was independently associated with reduced risk of early rebleeding (adjusted odds ratio [OR] 0.46; P < 0.001) and late rebleeding (adjusted OR 0.62; P < 0.001) compared with clipping. These significantly lower rebleeding rates with EBL were evident regardless of active bleeding or early colonoscopy. No significant differences were found between the treatments in the rates of initial hemostasis or mortality. Compared with clipping, EBL independently reduced the risk of needing interventional radiology (adjusted OR 0.37; P = 0.006) and prolonged length of hospital stay (adjusted OR 0.35; P < 0.001), but not need for surgery. Diverticulitis developed in one patient (0.16 %) following EBL and two patients (0.19 %) following clipping. Perforation occurred in two patients (0.31 %) following EBL and none following clipping. CONCLUSIONS : Analysis of our large endoscopy dataset suggests that EBL is an effective and safe endoscopic therapy for CDH, offering the advantages of lower early and late rebleeding rates, reduced need for interventional radiology, and shorter length of hospital stay.

Efficacy and Safety of Early vs Elective Colonoscopy for Acute Lower Gastrointestinal Bleeding.

BACKGROUND & AIMS: We performed a large, multicenter, randomized controlled trial to determine the efficacy and safety of early colonoscopy on outcomes of patients with acute lower gastrointestinal bleeding (ALGIB). METHODS: We performed an open-label study at 15 hospitals in Japan of 170 patients with ALGIB randomly assigned (1:1) to groups that underwent early colonoscopy (within 24 hours of initial visit to the hospital) or elective colonoscopy (24-96 hours after hospital admission). The primary outcome was identification of stigmata of recent hemorrhage (SRH). Secondary outcomes were rebleeding within 30 days, endoscopic treatment success, need for transfusion, length of stay, thrombotic events within 30 days, death within 30 days, and adverse events. RESULTS: SRH were identified in 17 of 79 patients (21.5%) in the early colonoscopy group vs 17 of 80 patients (21.3%) in the elective colonoscopy group (difference, 0.3; 95% confidence interval, -12.5 to 13.0; P = .967). Rebleeding within 30 days of hospital admission occurred in 15.3% of patients in the early colonoscopy group and 6.7% of patients in the elective colonoscopy group (difference, 8.6; 95% confidence interval, -1.4 to 18.7); there were no significant differences between groups in successful endoscopic treatment rate, transfusion rate, length of stay, thrombotic events, or death within 30 days. The adverse event of hemorrhagic shock occurred during bowel preparation in no patient in the early group vs 2 patients (2.5%) in the elective colonoscopy group. CONCLUSIONS: In a randomized controlled study, we found that colonoscopy within 24 hours after hospital admission did not increase SRH or reduce rebleeding compared with colonoscopy at 24-96 hours in patients with ALGIB. ClinicalTrials.gov, Numbers: UMIN000021129 and NCT03098173.

Identifying Bleeding Etiologies by Endoscopy Affected Outcomes in 10,342 Cases With Hematochezia: CODE BLUE-J Study.

INTRODUCTION: The bleeding source of hematochezia is unknown without performing colonoscopy. We sought to identify whether colonoscopy is a risk-stratifying tool to identify etiology and predict outcomes and whether presenting symptoms can differentiate the etiologies in patients with hematochezia. METHODS: This multicenter retrospective cohort study conducted at 49 hospitals across Japan analyzed 10,342 patients admitted for outpatient-onset acute hematochezia. RESULTS: Patients were mostly elderly population, and 29.5% had hemodynamic instability. Computed tomography was performed in 69.1% and colonoscopy in 87.7%. Diagnostic yield of colonoscopy reached 94.9%, most frequently diverticular bleeding. Thirty-day rebleeding rates were significantly higher with diverticulosis and small bowel bleeding than with other etiologies. In-hospital mortality was significantly higher with angioectasia, malignancy, rectal ulcer, and upper gastrointestinal bleeding. Colonoscopic treatment rates were significantly higher with diverticulosis, radiation colitis, angioectasia, rectal ulcer, and postendoscopy bleeding. More interventional radiology procedures were needed for diverticulosis and small bowel bleeding. Etiologies with favorable outcomes and low procedure rates were ischemic colitis and infectious colitis. Higher rates of painless hematochezia at presentation were significantly associated with multiple diseases, such as rectal ulcer, hemorrhoids, angioectasia, radiation colitis, and diverticulosis. The same was true in cases of hematochezia with diarrhea, fever, and hemodynamic instability. DISCUSSION: This nationwide data set of acute hematochezia highlights the importance of colonoscopy in accurately detecting bleeding etiologies that stratify patients at high or low risk of adverse outcomes and those who will likely require more procedures. Predicting different bleeding etiologies based on initial presentation would be challenging.

Cumulative evidence for reducing recurrence of colonic diverticular bleeding using endoscopic clipping versus band ligation: Systematic review and meta-analysis.

BACKGROUND AND AIM: Either clipping or band ligation will become the most common endoscopic treatment for colonic diverticular bleeding (CDB). Rebleeding is a significant clinical outcome of CDB, but there is no cumulative evidence comparing reduction of short-term and long-term rebleeding between them. Thus, we conducted a systematic review and meta-analysis to determine which endoscopic treatment is more effective to reduce recurrence of CDB. METHODS: A comprehensive search of the databases PubMed/MEDLINE and Embase was performed through December 2019. Main outcomes were early and late rebleeding rates, defined as bleeding within 30 days and 1 year of endoscopic therapy for CDB. Initial hemostasis, need for transcatheter arterial embolization, or surgery were also assessed. Overall pooled estimates were calculated. RESULTS: Sixteen studies fulfilled the eligibility criteria, and a total of 790 participants were included. The pooled prevalence of early rebleeding was significantly lower for band ligation than clipping (0.08 vs 0.19; heterogeneity test, P = 0.012). The pooled prevalence of late rebleeding was significantly lower for band ligation than clipping (0.09 vs 0.29; heterogeneity test, P = 0.024). No significant difference of initial hemostasis rate was noted between the two groups. Pooled prevalence of need for transcatheter arterial embolization or surgery was significantly lower for band ligation than clipping (0.01 vs 0.02; heterogeneity test, P = 0.031). There were two cases with colonic diverticulitis due to band ligation but none in clipping. CONCLUSION: Band ligation therapy was more effective compared with clipping to reduce recurrence of colonic diverticular hemorrhage over short-term and long-term durations.

[A Case of Remnant Gastric Necrosis after Laparoscopy-Assisted Distal Gastrectomy].

A 77-year-old man with a medical history of hypertension, dyslipidemia, angina pectoris, and internal carotid artery stenosis underwent laparoscopy-assisted distal gastrectomy, D2 lymphadenectomy, and Billroth Ⅰ reconstruction for advanced gastric cancer. Hematologic examination revealed severe anemia on postoperative day 2, and abdominal CT scan detected contrast media leakage into the remnant gastric lumen. Upper gastrointestinal endoscopy revealed mucosal necrosis and ulceration of a large range. The patient recovered with conservative treatment and was discharged on postoperative day 18. Endoscopic balloon dilation was required to improve anastomotic stenosis after discharge, after which the patient received adjuvant chemotherapy. The stomach is resistant to ischemic changes because of the microvascular networks in the stomach wall; thus, gastric remnant necrosis after gastrectomy is rare. However, for patients with arterial sclerosis, such as in this case, physicians must consider the range of gastrectomy and reconstruction methods.

[A Case of Laparoscopy-Assisted Surgery for Intestinal Malignant Lymphoma with Bowel Obstruction].

An 83-year-old woman visited our emergency department with a chief complaint of abdominal pain and vomiting. Abdominal computed tomography showed thickening of the wall of the small intestine in the right middle abdomen and marked bowel dilation and fluid retention in the oral side of the small intestine. The patient was diagnosed with adhesive bowel obstruction and hospitalized for conservative treatment. However, the treatment was unsuccessful, and laparoscopic surgery was performed. The intraoperative findings included thickening of the wall and hardening of the obstructed part, suggestive of an intestinal tumor; thus, this part was resected. A histopathological examination revealed diffuse infiltration of large-sized atypical lymphocytes in the tumor, and diffuse large B-cell lymphoma was diagnosed through immunochemical staining. The postoperative course was uneventful, and the lymphoma has not recurred. Intestinal malignant lymphoma rarely causes bowel obstruction without invagination. Here, we report this case and review the literature.