Optimization of upper gastrointestinal endoscopy: value of real-time gastric juice analysis

Diagnostic Accuracy of EndoFaster® and Narrow-Band Imaging Endoscopy in Patients with Impaired Gastric Acid Secretion: A Real-Time Prospective Study

BACKGROUND

EndoFaster® analyzes gastric juice in real time during gastroscopy allowing the detection of hypo-achlorhydric conditions, like corpus atrophic gastritis. Narrow-band imaging (NBI) endoscopy allows to accurately detect and perform target biopsies in areas of intestinal metaplasia, a histological change often associated to corpus atrophic gastritis.

AIMS

To compare the diagnostic accuracy of EndoFaster® with histological evaluation for corpus atrophic gastritis through high-resolution (HR) NBI targeted biopsies.

METHODS

Prospective study on consecutive adult patients undergoing gastroscopy between April and November 2018. Patients in therapy with proton pump inhibitors, previous gastric surgery, and/or known gastric neoplasia were excluded. At the beginning of gastroscopy, gastric juice was aspirated and analyzed by EndoFaster® in 15 seconds. Endoscopists were blinded to the report of EndoFaster®. Evaluation of gastric mucosa in HR-white light was firstly performed, then with HR-NBI allowing to perform targeted biopsies on areas suspected for intestinal metaplasia; otherwise, biopsies were performed according to the updated Sydney System protocol and sent for histopathological evaluation.

RESULTS

Overall, 124 patients were included [64% F; 56 (18-85) years]. Corpus atrophic gastritis was present in 41.9% of patients. EndoFaster® showed an accuracy for corpus atrophic gastritis diagnosis, compared to histopathological evaluation as gold standard, of 87.1% and a sensitivity, specificity, PPV, and NPV of 78.8%, 93.1%, 89.1%, and 85.9%, respectively. pH showed a positive correlation with the severity score of atrophy (r = 0.67, 95% CI: 0.73-0.81, and p < 0.0001). EndoFaster® allowed to diagnose corpus atrophic gastritis in 3.7% of patients negative to NBI (corpus atrophic gastritis without intestinal metaplasia).

CONCLUSION

EndoFaster® seems a promising tool to diagnose corpus atrophic gastritis. The evaluation of hypo-achlorhydria during gastroscopy can address bioptic sampling in corpus atrophic gastritis patients without intestinal metaplasia.

Real-time diagnosis of H. pylori infection during endoscopy: Accuracy of an innovative tool (EndoFaster)

BACKGROUND

EndoFaster is novel device able to perform real-time ammonium measurement in gastric juice allowing H. pylori diagnosis during endoscopy. This large study aimed to validate the accuracy of EndoFaster for real-time H. pylori detection.

METHODS

Consecutive patients who underwent upper endoscopy in two centres were prospectively enrolled. During endoscopy, 4 ml of gastric juice were aspirated to perform automatic analysis by EndoFaster within 90 seconds, and H. pylori was considered present (>62 ppm/ml) or absent (≤62 ppm/ml). Accuracy was measured by using histology as gold standard, and (13)C-urea breath test (UBT) in discordant cases. Accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) were calculated.

RESULTS

Overall, 189 patients were enrolled, but in seven (3.4%) the aspirated gastric juice amount was insufficient to perform the test. The accuracy, sensitivity, specificity, PPV, and NPV were 87.4%, 90.3%, 85.5%, 80.2%, 93.1%, respectively, and 92.6%, 97.1%, 89.7%, 85.9%, 98.0%, respectively, when H. pylori status was reclassified according to the UBT result in discordant cases.

CONCLUSIONS

This study found a high accuracy/feasibility of EndoFaster for real-time H. pylori diagnosis. Use of EndoFaster may allow selecting those patients in whom routine gastric biopsies could be avoided.