Interobserver Agreement of Endoscopic Diagnosis of Helicobacter Pylori Based on the Arrangement of Gastric Collecting Venules: Prospective and Multicenter Study

We designed a prospective study including patients who will undergo upper gastrointestinal endoscopy from July 2019 to June 2020 at the Endoscopy Unit of Hospital Clinic of Barcelona.

The Ethics Committee of Hospital Clinic of Barcelona approved the study.

Upper gastrointestinal endoscopies will be performed with high definition endoscopes (Olympus, Germany) without magnification by three endoscopists. One of the endoscopists is considered as an expert with more than 20 years of experience and prior training in Japanese centers. All the examinations will be performed with sedation controlled by an anesthesiologist. After the routine examination of the esophagus, stomach, and duodenum, close observation will be carried out at the distal part of the lesser curvature and pictures will be taken. The Olympus system will be used for image storing and text reporting.

The presence of a regular or irregular arrangement of collecting venules will be evaluated in real time during gastric exploration in the lower part of the lesser curvature of the gastric body with good insufflation, close to the incisura angularis. If minute red points were visible regularly and homogenously, the finding will be scored as RAC positive (RAC+). If this finding was absent or there was a patchy distribution at the site of close observation, it will be defined as RAC negative (RAC-).

The following baseline characteristics will be collected: age, sex, antibiotics, proton-pump inhibitors, non-steroidal anti-inflammatory drugs (NSAIDs), antithrombotic or anticoagulant use in the last two weeks, history of Hp eradication and detection of significant endoscopic findings (erosive duodenitis, non-erosive duodenitis, duodenal ulcer, erosive gastritis, gastric ulcer and signs of atrophic gastritis or intestinal metaplasia).