Competence development in ERCP: the learning curve of novice trainees

Background and study aim: Measures for competence in endoscopic retrograde cholangiopancreatography (ERCP) during training are poorly defined. Currently, various training and accreditation programs base verification of competence on performance of a minimum number of procedures. There is a general awareness that procedural competence certification should be based on objective performance criteria. Continuous self-assessment using a Rotterdam Assessment Form for ERCP (RAF-E) can provide insight into trainee performance. The study aim was to express development in ERCP competence as a learning curve. Methods: ERCP trainees at a tertiary referral center in the Netherlands were invited to participate. Performed procedures were appraised using RAF-E. Indication for each ERCP and presence of a virgin papilla were documented. Complexity was graded on a 3-point scale. The primary outcome parameter was common bile duct (CBD) cannulation success rate. Success of the intended therapeutic interventions was additionally expressed as a learning curve. Results: 15 trainees were included. 1541 ERCPs (624 procedures in native papillary anatomy) were assessed through RAF-E. Unassisted CBD cannulation success rate improved from 36% at baseline to 85% after 200 procedures (P<0.001), and in 624 patients with a virgin papilla from 22% at baseline to 68% after 180 procedures (P<0.001). Learning curves for therapeutic interventions showed significant improvements for successful sphincterotomy (P=0.01) and stent placement (P<0.001). Conclusions: Learning curves are a valuable means for assessing competence in ERCP. Differences in learning curves can be shown with RAF-E. Verification of competence should be based on actual performance, instead of minimum numbers

Expression and subcellular distribution of toll-like receptors TLR4, TLR5 and TLR9 on the gastric epithelium in Helicobacter pylori infection

Toll-like receptors (TLRs) expressed by mucosal epithelium play an essential role in the defense against microbes by recognizing conserved bacterial molecules. For the first time TLR4, TLR5 and TLR9 have been microanatomically localized in patients with noninflamed gastric mucosa and Helicobacter pylori gastritis by immunohistochemistry. Because polarized expression of TLRs in apical and basolateral epithelial compartments is thought to modulate mucosal immunity, subcellular TLR distribution by gastric epithelium was investigated using confocal microscopy. TLR4, TLR5 and TLR9 were expressed by gastric epithelium in antrum and corpus of all patients with H. pylori gastritis (n = 14) and with noninflamed gastric mucosa (n = 5). TLR4 was expressed at the apical and the basolateral pole of the gastric epithelium as well in noninflamed gastric mucosa as in H. pylori gastritis. TLR5 and TLR9 expression in the noninflamed gastric mucosa was identical to that of TLR4 with localization at the apical and the basolateral epithelial pole. However, in H. pylori gastritis TLR5 and TLR9 expression on the gastric epithelium changed to an exclusive basolateral localization without detectable expression at the apical pole. In the human stomach, the gastric epithelium expressed TLR4, TLR5 and TLR9, which gives it the possibility to interact with H. pylori. Furthermore, gastric epithelial TLR4 expression is highly polarized in an apical and a basolateral compartment, whereas TLR5 and TLR9 polarization seems to be a process dynamically influenced by H. pylori infection. This polarized and dynamically regulated gastric epithelial expression of TLRs supports a sentinel role for these receptors in the mucosal immunity to H. pylori