Confocal laser endomicroscopy for diagnosis of Helicobacter pylori infection: a prospective study.

BACKGROUND AND AIM: Confocal laser endomicroscopy (CLE) is a new endoscopy technique for subsurface analysis of the gastric mucosa and in vivo histology examination during endoscopy. We aimed to compare the clinical applicability and predictive power of CLE with the diagnosis of Helicobacter pylori infection in patients with gastrointestinal symptoms. METHODS: A total of 103 consecutive patients scheduled to undergo endoscopy were enrolled. CLE image criteria for H. pylori infection were established in a pilot study of 20 patients, then images for 83 consecutive patients were prospectively evaluated, and data were correlated with the final diagnosis of H. pylori infection in a blinded manner. RESULTS: We found good association between histopathology and CLE findings. H. pylori infection was identified by CLE with any of the following three features: white spots, neutrophils and microabscesses. The accuracy, sensitivity and specificity of CLE diagnosis of H. pylori infection were 92.8%, 89.2% and 95.7%, respectively. The mean kappa-value for interobserver agreement in the prediction of H. pylori infection was 0.78. Neutrophils were the best diagnostic feature and had good sensitivity (83.8%) and specificity (97.8%). H. pylori-associated changes were more common in the antrum than in the corpus among infected patients (P < 0.001). CONCLUSIONS: H. pylori infection can be identified by specific cellular and subcellular changes of the surface gastric mucosa with CLE. CLE is a novel, useful method for predicting H. pylori infection in vivo during endoscopy.