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

Abstract

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 (ROC) 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.

Figures

Figure 1

Confocal laser endomicroscopy classification of Helicobacter pylori-associated gastritis severity in gastric antrum and corpus. A, B: Normal mucosa with normal antral and corporal pits, and free of fluorescein leakage; C, D: Active inflammation (mild) with slightly distorted pits and intact epithelium, scattered focal fluorescein leakage (arrows); E, F: Active inflammation (moderate) with more distorted pits and partly destroyed epithelium (arrows), and more fluorescein leakage; G, H: Active inflammation (marked) with markedly distorted pits and dilated opening, destroyed epithelium (arrows), and widespread fluorescein leakage; I, J: Glandular atrophy with decreased gastric pits and markedly dilated opening (arrows); K, L: Intestinal metaplasia with villous-like gastric pits and goblet cells (black arrows), absorptive cells (white arrows) and brush border (arrowheads) appearing. CLE: Confocal laser endomicroscopy.

Figure 2

Box plot analysis of mean confocal gastritis score in 4 Helicobacter pylori test groups. mCGS: Mean confocal gastritis score.

Figure 3

Receiver operating characteristic curve analysis showing the sensitivity and specificity of confocal laser endomicroscopy and mean confocal gastritis score for diagnosing Helicobacter pylori infection. AUC: Area under curve; mCGS: Mean confocal gastritis score.

Figure 4

Correlation between mean confocal gastritis score and mean histologic gastritis score for histological chronic inflammation (R2 = 0.795, A) and activity (R2 = 0.736, B). mCGS: Mean confocal gastritis score; mHGS: Mean histologic gastritis score.

Figure 5

Gastric pits on confocal laser endomicroscopy images. CLE: Confocal laser endomicroscopy.

Figure 6

Prevalence of intestinal metaplasia features on confocal laser endomicroscopy images. IM: Intestinal metaplasia; CLE: Confocal laser endomicroscopy.