Neutrophil extracellular trap formation and its implications in nonsteroidal anti-inflammatory drug-induced small intestinal injury.

BACKGROUND AND AIM: Nonsteroidal anti-inflammatory drugs (NSAIDs) damage the small intestine via neutrophil infiltration driven by the mucosal invasion of enterobacteria. The antimicrobial function of neutrophils is partially dependent on neutrophil extracellular traps (NETs). Excessive NET formation has been associated with several inflammatory diseases. Here, we aimed to investigate the role of NETs in NSAID-induced small intestinal damage using human samples and an experimental mouse model. METHODS: Human small intestine specimens were obtained from NSAID users during double-balloon enteroscopy. Wild-type, protein arginine deiminase 4 (PAD4) knockout, and antibiotic-treated mice were administered indomethacin to induce small intestinal injury. The expression of NET-associated proteins, including PAD4, citrullinated histone H3 (CitH3), cell-free DNA, and myeloperoxidase (MPO), was evaluated. RESULTS: The double-positive stained area with CitH3 and MPO, which is specific for neutrophil-derived extracellular traps, was significantly high in the injured small intestinal mucosa of NSAID users. In a mouse model, small intestinal damage developed at 6 h after indomethacin administration, accompanied by increased mRNA levels of interleukin-1ß and keratinocyte chemoattractant and elevated NET-associated protein levels of PAD4, CitH3, and MPO in small intestine and serum levels of cell-free DNA. Both genetic deletion and pharmacological inhibition of PAD4 attenuated this damage by reducing the mRNA expression of inflammatory cytokines and NET-associated proteins. Furthermore, mice pretreated with antibiotics showed resistance to indomethacin-induced small intestinal damage, with less NET formation. CONCLUSION: These results suggest that NETs aggravate NSAID-induced small intestinal injury. Therefore, NET inhibition could be a potential treatment for NSAID-induced small intestinal injury.

Esophageal submucosal hematoma during transnasal endoscopy: A rare case report.

Esophageal submucosal hematoma is a rare, often incidental complication of therapeutic endoscopic procedures marked by disrupted blood vessels beneath the esophageal mucosa, forming a hematoma. We report the unique case of a severely thin and alcoholic 38-year-old woman with a history of reflux esophagitis who developed an esophageal submucosal hematoma during an unsedated transnasal endoscopy for health check-up. During the procedure, the patient experienced strong vomiting reflexes and vomited blood, leading to the initial suspicion of either Mallory-Weiss syndrome or epistaxis. However, subsequent sedated endoscopy revealed an esophageal submucosal tumor-like lesion and a mucosal laceration with blood clots, prompting a dual diagnosis of esophageal submucosal hematoma and Mallory-Weiss syndrome. The bleeding was not severe enough to require hemostatic intervention. The patient opted for conservative treatment with vonoprazan, which resulted in the improvement and healing of the hematoma within 28 days. This is the first report of an esophageal submucosal hematoma during transnasal endoscopy and emphasizes the importance of including an esophageal submucosal hematoma and Mallory-Weiss syndrome in the differential diagnosis of hematemesis encountered in similar scenarios. Factors such as severe thinness, daily alcohol consumption, and reflux esophagitis may have possibly contributed to the development of the esophageal submucosal hematoma in this patient.

The impact of COVID-19 on Japanese patients with eosinophilic gastrointestinal disorders during the vaccination era.

Background: Eosinophilic gastrointestinal disorders (EGIDs) are chronic allergic diseases categorized as eosinophilic esophagitis (EoE) and non-EoE EGIDs. Few studies regarding the association between EGIDs and coronavirus disease 2019 (COVID-19) have been reported. Although most Japanese individuals received the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine, the incidence of COVID-19 remained high in 2022. This study examines the incidence of COVID-19 in patients with EGIDs during the vaccination era. Methods: Patients with EGIDs who visited our department between October and December 2022 were enrolled in the study. The incidence and severity of COVID-19 prior to October 1, 2022 were determined. Patients who reported having COVID-19 also reported their hospitalization history, intensive care unit admissions, and EGID flares. The number of SARS-CoV-2 vaccinations received and treatment for EGIDs were obtained from the patients' medical records. Results: Of 111 patients with EGIDs (65 with EoE and 46 with non-EoE EGIDs) included in this study, 31 (28%) patients reported having COVID-19, including 14 (22%) with EoE and 17 (37%) with non-EoE EGIDs. Fifty-nine (84%) patients received two or more vaccinations, and 11 (16%) patients received no vaccinations. COVID-19 was mild in all but one patient who had moderate symptoms. COVID-19 was not associated with EGID flares. EGID treatments and an unvaccinated status were not associated with an increased risk of COVID-19. Conclusion: COVID-19 was mild in patients with EGIDs and not associated with EGIDs flares during the vaccination era. There was a relatively high incidence of COVID-19 among patients with non-EoE EGIDs.

Importance of Bowel Habits in Predicting Inadequate Bowel Preparation: A Prospective Observational Study.

OBJECTIVES: Inadequate bowel preparation (BP) negatively affects the efficacy and quality of colonoscopy. Although constipation has already been reported as one of the most important predictors of inadequate BP, there is limited information on the relation between inadequate BP and bowel habits including constipation-related symptoms, medications, and severity of constipation. METHODS: This single-center, prospective observational study was conducted between August 2019 and May 2020. All participants answered questionnaires regarding personal bowel habits and received low-volume polyethylene glycol plus ascorbic acid for outpatient colonoscopy. Severity of constipation was evaluated by constipation scoring system. Bowel preparation cleansing was evaluated using Boston Bowel Preparation Scale (BBPS). Potential predictors of inadequate BP were analyzed using multivariate logistic regression models. RESULTS: Overall, 1054 patients were enrolled, of which, 105 (10%) had inadequate BP (total BBPS ≤ 6 or any segmental BBPS < 2). The risk of inadequate BP increased with constipation severity (P = 0.01). Multivariate analysis showed that frequent straining (> 25% of defecations) (OR 2.09, 95% CI: 1.33-3.28) and chronic use of stimulant laxatives (OR 2.57, 95% CI: 1.59-4.17) were significant predictors of inadequate BP, among personal bowel habits. CONCLUSION: Frequent straining and chronic use of stimulant laxatives were predictors of inadequate BP. An intensified preparation regimen should be considered for severely constipated patients with straining and chronic use of stimulant laxatives.

Two cases of eosinophilic gastrointestinal disorder due to newly appearing food allergies after cord blood transplantation.

Eosinophilic gastrointestinal disorders (EGIDs) are infrequent complications after allogeneic hematopoietic cell transplantation (allo-HCT). Furthermore, it is well-known that allergic diseases are transferable after allo-HCT from allergic donors to non-allergic recipients. However, the type of graft-versus host disease (GVHD) prophylaxis that leads to allergic disease transfer is unclear. Furthermore, no study has reported a case of acquired food allergy resulting in EGID that was detected based on the clinical course and the detection of antigen-specific immunoglobulin E after allo-HCT. We encountered two patients with acute leukemia accompanied by eosinophilic esophagitis (EoE) and eosinophilic gastroenteritis (EGE) due to newly appearing food allergy after cord blood transplantation (CBT) with T-cell non-depletion GVHD prophylaxis. Despite having no history of allergic disease, the patients experienced allergic symptoms due to dairy products (Case 1) and eggs (Case 2) after CBT. They subsequently experienced severe nausea, heartburn, and anorexia (Case 1) and diarrhea (Case 2). Cases 1 and 2 were diagnosed with EoE and EGE, respectively, based on endoscopic and histological examinations. Dietary treatment without steroids improved the symptoms in both cases. These cases highlight that the unexpected transfer of food allergy after CBT can lead to EGIDs, especially in patients receiving T-cell non-depletion GVHD prophylaxis.

Efficacy and tolerability of 1 L polyethylene glycol plus ascorbic acid with senna versus 2 L polyethylene glycol plus ascorbic acid for colonoscopic bowel preparation: Prospective, randomized, investigator-blinded trial.

OBJECTIVES: Low-volume polyethylene glycol plus ascorbic acid (PEG-Asc) reduces the dosage of colonoscopic bowel preparation (BP) solution, but is still poorly tolerated. Adding laxatives to the BP solution reduces the volume of fluid required, without affecting quality. This study aimed to compare 1 L PEG-Asc plus 24 mg senna (1L-PEG/AS) and conventional 2 L PEG-Asc (2L-PEG/A) regimens on BP quality and patient tolerability. METHODS: A single-center, randomized, investigator-blinded, noninferiority trial was performed between June and August 2022. Outpatients scheduled for colonoscopy were randomized (1:1) to the 1L-PEG/AS or 2L-PEG/A group. The Boston Bowel Preparation Scale (BBPS) was used to evaluate BP quality. Adverse events and tolerability were surveyed using questionnaires. RESULTS: Overall, 344 patients received 1L-PEG/AS or 2L-PEG/A regimens. The baseline characteristics and adverse events of the two groups were comparable. The 1L-PEG/AS group showed noninferior adequate BP rates compared with the 2L-PEG/A group (88% vs. 89%, P = 1.00); overall BBPS was 7.1 ± 1.5 and 7.2 ± 1.5, respectively (P = 0.39). Higher willingness to repeat the BP was observed in the 1L-PEG/AS group (85% vs. 62%, P < 0.01). CONCLUSIONS: The 1L-PEG/AS regimen was comparable to the 2L-PEG/A regimen in terms of BP adequacy, requiring lower BP solution volumes, with better patient tolerance. Thus, it may be a suitable alternative to the conventional BP solution for colonoscopy. The Japan Registry of Clinical Trials (jRCT1051220043).

[Current real-world treatments for Japanese patients with eosinophilic esophagitis].

A total of 306 patients with eosinophilic esophagitis (EoE) were analyzed at our department. Proton pump inhibitors or potassium-competitive acid blockers were used as the first-line treatment in 286 (93.5%) patients. Fifty-five (18.0%) patients received topical steroid swallowing therapy. During 17.7-month mean follow-up, 46.4% of the patients were followed-up with no medications, 37.3% of the patients received maintenance or on-demand therapy using acid-suppressive drugs, and 9.8% of the patients received maintenance therapy with steroid swallowing. The majority of patients with EoE were treated using a therapeutic strategy similar to that used for gastroesophageal reflux disease. However, some patients were refractory to the treatment. Current real-world treatment strategies for Japanese patients with EoE are clarified.

Long-term rebleeding rate and predictive factors of rebleeding after capsule endoscopy in patients with obscure GI bleeding.

BACKGROUND AND AIMS: The incidence of rebleeding in obscure GI bleeding (OGIB) remains unclear. This study used capsule endoscopy (CE) to determine the long-term rebleeding rate and predictive factors for rebleeding in patients with OGIB. METHODS: This single-center, observational study enrolled consecutive patients with OGIB who underwent CE as the first small intestinal examination between March 2004 and December 2015 and were followed up through medical records or letters. RESULTS: Three hundred eighty-nine patients were included in the analysis. Survival curve analysis showed that the overall cumulative rebleeding rate in OGIB during the 5 years was 41.7%. Multivariate analysis using the Cox proportional hazards model revealed that overt OGIB (hazard ratio [HR], 2.017; 95% confidence interval [CI], 1.299-3.131; P = .002), anticoagulants (HR, 1.930; 95% CI, 1.093-3.410; P = .023), positive balloon-assisted enteroscopy findings after CE (HR, 2.927; 95% CI, 1.791-4.783; P < .001), and iron supplements without therapeutic intervention (HR, 2.202; 95% CI, 1.386-3.498; P = .001) were associated with rebleeding, whereas a higher minimum hemoglobin level (HR, .902; 95% CI, .834-.975; P = .009) and therapeutic intervention (HR, .288; 95% CI, .145-.570; P < .001) significantly reduced the risk of rebleeding. Among the Charlson Comorbidity Index components, liver cirrhosis was an independent predictor associated with rebleeding in patients with OGIB (HR, 4.362; 95% CI, 2.622-7.259; P < .001) and in patients with negative CE findings (HR, 8.961; 95% CI, 4.424-18.150; P < .001). CONCLUSIONS: Rebleeding is common during the long-term follow-up of patients with OGIB. Careful follow-up is required for patients with liver cirrhosis or previous massive bleeding.

Pirfenidone prevents esophageal stricture by inhibiting nucleotide binding oligomerization domain like receptor protein 3 inflammasome activation.

BACKGROUND AND AIM: Esophageal injury often results in a scar, leading to refractory strictures. The NLRP3 inflammasome activates caspase-1, causing the maturation of interleukin (IL)-1ß. Here, we aimed to investigate the preventive effect of pirfenidone (PFD), an antifibrotic drug, on esophageal stricture after ulcer healing and studied its mechanism by focusing on the activation of the NLRP3 inflammasome. METHODS: Esophageal ulcers were induced in rats via the local application of acetic acid in the serosa. PFD was intraperitoneally administered to the rats 3 days after ulcer induction. The effect of PFD on esophageal stricture after ulcer healing was assessed by esophagography on day 9. The protein levels of mature caspase-1 and IL-1ß were assessed by western blotting. RESULTS: The ulcers fully developed 3 days after induction and were almost scarred by day 9 with severe strictures. PFD promoted ulcer healing and attenuated fibrotic collagen in the submucosa by suppressing the increase in NLRP3, cleaved caspase-1, and mature IL-1ß expression, improving stricture rate (PFD vs vehicle = 55% vs 81%). Exogenous IL-1ß abolished the therapeutic effects of PFD on ulcer healing and stricture formation. Furthermore, NLRP3 and caspase-1 inhibitors mimicked the effects of PFD on ulcer healing and stricture formation, with suppression of the increase in cleaved caspase-1 and mature IL-1ß proteins and expression of fibrosis-related molecules including transforming growth factor (TGF)-ß1. CONCLUSION: The NLRP3 inflammasome promotes esophageal stricture formation following ulcer healing, and PFD exerts potential prophylactic activity against strictures, possibly via the inhibition of the NLRP3/IL-1ß/TGF-ß1 axis.

Clinical Implication of Preoperative C-Reactive Protein/Albumin Ratio in Malignant Transformation of Intraductal Papillary Mucinous Neoplasm: A Propensity Score Analysis.

BACKGROUND: Inflammation-based scoring has been reported to be useful for predicting the recurrence and prognosis of various carcinomas. This study retrospectively investigated the relationship between inflammation-based score and intraductal papillary mucinous neoplasms (IPMNs). METHODS: Between January 2013 and October 2018, we enrolled 417 consecutive patients with pancreatic tumors who received surgical resections at our hospital. The main outcome was the association between the preoperative inflammation-based score and their accuracy in predicting malignant transformation of IPMN. RESULTS: Seventy six patients were eligible. Pathological findings indicated that 35 patients had low-grade dysplasia, 18 had high-grade dysplasia, and 23 had invasive carcinomas. As the C-reactive protein albumin ratio (CAR) was higher, malignant transformation of IPMNs also increased (p = 0.007). In comparing CARhigh and CARlow using cutoff value, the results using a propensity score analysis showed that the CARhigh group predicted malignant transformation of IPMNs (odds ratio, 4.18; 95% confidence interval, 1.37-12.8; p = 0.01). In the CARhigh group, disease-free survival (DFS) was significantly shorter (p = 0.04). In the worrisome features, the AUC for the accuracy of malignant transformation with CARhigh was 0.84 when combining with the MPD findings. CONCLUSIONS: Preoperative CAR could be a predictive marker of malignant transformation of IPMNs.