Classification of histological severity of Helicobacter pylori - associated gastritis by confocal laser endomicroscopy

AIM: To classify the histological severity of Helicobacter pylori (H. pylori) infection-associated gastritis by confocal laser endomicroscopy (CLE). METHODS: Patients with upper gastrointestinal symptoms or individuals who were screened for gastric cancer were enrolled in this study. Histological severity of H. pylori infection-associated gastritis was graded according to the established CLE criteria. Diagnostic value of CLE for histological gastritis was investigated and compared with that of white light endoscopy (WLE). Targeted biopsies from the sites observed by CLE were performed. RESULTS: A total of 118 consecutive patients with H. pylori infection-associated gastritis were enrolled in this study. Receiver operating characteristic curve analysis showed that the sensitivity and specificity of CLE were 82.9% and 90.9% for the diagnosis of H. pylori infection, 94.6% and 97.4% for predicting gastric normal mucosa, 98.5% and 94.6% for predicting histological active inflammation, 92.9% and 95.2% for predicting glandular atrophy, 98.6% and 100% for diagnosing intestinal metaplasia, respectively. Post-CLE image analysis showed that goblet cells and absorptive cells were the two most common parameters on the CLE-diagnosed intestinal metaplasia (IM) images (P < 0.001). More histological lesions of the stomach could be found by CLE than by WLE (P < 0.001). CONCLUSION: CLE can accurately show the histological severity of H. pylori infection-associated gastritis. Mapping IM by CLE has a rather good diagnostic accuracy.