The risk of endoscopic mucosal resection in the setting of clopidogrel use.

Objective. Guidelines on antiplatelet medication use during endoscopy are based on limited evidence. We investigate the risk of bleeding and ischemic events in patients undergoing endoscopic mucosal resection (EMR) of esophageal lesions in the setting of scheduled cessation and prompt resumption of clopidogrel. Design. Single centre retrospective review. Patients. Patients undergoing EMR of esophageal lesions. Interventions. Use of clopidogrel before EMR and resumption after EMR. Patients cease antiplatelets and anticoagulants 7 days before EMR and resume clopidogrel 2 days after EMR in average risk patients. Main Outcomes. Gastrointestinal bleeding (GIB) and ischemic events (IE) within 30 days of EMR. Results. 798 patients underwent 1716 EMR. 776 EMR were performed on patients on at least 1 antiplatelet/anticoagulant (APAC). 17 EMR were performed following clopidogrel cessation. There were 14 GIB and 2 IE. GIB risk in the setting of recent clopidogrel alone (0%) was comparable to those not on APAC (1.1%) (P = 1.0). IE risk on clopidogrel (6.3%) was higher than those not on APAC (0.1%) (P = 0.03). Limitations. Retrospective study. Conclusions. Temporary cessation of clopidogrel before EMR and prompt resumption is not associated with an increased risk of gastrointestinal bleeding but may be associated with increased ischemic events.

Safety of prior endoscopic mucosal resection in patients receiving radiofrequency ablation of Barrett's esophagus.

BACKGROUND & AIMS: Radiofrequency ablation (RFA) is safe and effective treatment for flat dysplasia associated with Barrett's esophagus (BE). However, there are limited data on the safety of RFA in patients who had prior endoscopic mucosal resection (EMR), which might increase the risk of complications. We compared complications and histologic outcomes between patients who had EMR before RFA and those who received only RFA. METHODS: We performed a retrospective analysis of data collected from patients treated for BE, associated with dysplasia or intramucosal cancer, at the Mayo Clinic in Rochester, Minnesota, from 1998-2009. Patients were divided into groups that had RFA after EMR (group 1, n = 44) or only RFA (group 2, n = 46). We compared the incidence of complications (strictures, bleeding, and esophageal perforation) and histologic features (complete resolution of dysplasia and complete resolution of intestinal metaplasia [CR-IM]) between groups. Logistic regression analysis was performed to assess predictors of stricture formation. RESULTS: Stricture rates were 14% in group 1 and 9% in group 2 (odds ratio, 1.53; 95% confidence interval [CI], 0.26-9.74). The rates of CR-IM were 43% in group 1 and 74% in group 2 (odds ratio, 0.33; 95% CI, 0.14-0.78). The rates of complete resolution of dysplasia were 76% in group 1 and 71% in group 2 (odds ratio, 1.28; 95% CI, 0.39-4.17). The adjusted odds ratio for CR-IM in group 1 (adjusting for age, segment length, and grade of dysplasia) was 0.50 (95% CI, 0.15-1.66). CONCLUSIONS: Stricture rates among patients who receive only RFA are comparable to those of patients who had prior EMR. EMR appears safe to perform prior to RFA.

Prohibitin inhibits tumor necrosis factor alpha-induced nuclear factor-kappa B nuclear translocation via the novel mechanism of decreasing importin alpha3 expression.

Expression of prohibitin 1 (PHB), a multifunctional protein in the cell, is decreased during inflammatory bowel disease (IBD). Little is known regarding the regulation and role of PHB during intestinal inflammation. We examined the effect of tumor necrosis factor alpha (TNF-alpha), a cytokine that plays a central role in the pathogenesis of IBD, on PHB expression and the effect of sustained PHB expression on TNF-alpha activation of nuclear factor-kappa B (NF-kappaB) and epithelial barrier dysfunction, two hallmarks of intestinal inflammation. We show that TNF-alpha decreased PHB protein and mRNA abundance in intestinal epithelial cells in vitro and in colon mucosa in vivo. Sustained expression of prohibitin in intestinal epithelial cells in vitro and in vivo (prohibitin transgenic mice, PHB TG) resulted in a marked decrease in TNF-alpha-induced nuclear translocation of the NF-kappaB protein p65, NF-kappaB/DNA binding, and NF-kappaB-mediated transcriptional activation despite robust IkappaB-alpha phosphorylation and degradation and increased cytosolic p65. Cells overexpressing PHB were protected from TNF-alpha-induced increased epithelial permeability. Expression of importin alpha3, a protein involved in p50/p65 nuclear import, was decreased in cells overexpressing PHB and in colon mucosa of PHB TG mice. Restoration of importin alpha3 levels sustained NF-kappaB activation by TNF-alpha during PHB transfection. These results suggest that PHB inhibits NF-kappaB nuclear translocation via a novel mechanism involving alteration of importin alpha3 levels. TNF-alpha decreases PHB expression in intestinal epithelial cells and restoration of PHB expression in these cells can protect against the deleterious effects of TNF-alpha and NF-kappaB on barrier function.