Comparison of Different Histological Staining Methods for Detection of Helicobacter pylori Infection in Gastric Biopsy

Background: Helicobacter pylori gastritis affects two-thirds of the world's human population. Among various invasive and non-invasive tests, histology play a very important role in detecting H. pylori in gastric biopsies. In histology, for detection of H. pylori, we use different histological staining techniques like routine haematoxylin & eosin (H&E) stain, Giemsa stain, Gimenez stain, and periodic acid Schiff - Alcian blue (PAS-AB) stain. Objective: Aim of our study was to evaluate these different histopathological staining techniques for detecting H. pylori in gastric mucosal biopsies and to determine the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of H&E stain, Gemenez stain and PAS-AB in the detection of H. pylori in gastric biopsies using Giemsa stain as the reference standard. Materials and Methods: It was a prospective descriptive study design of 45 gastric biopsies of patients having gastritis. This study was conducted at Vivekananda Polyclinic and Institute of Medical Sciences over a period of one year, from March 2021 to February 2022. From each formalin-fixed paraffin-embedded block, four glass slides were prepared and stained with H&E stain, Giemsa stains, Gemenez stain, and PAS-AB stain to detect the presence/absence of H. pylori in gastric biopsies. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were assessed. Results: Various staining techniques for detecting H. pylori in gastric mucosal biopsies were compared. In reference to Giemsa stain results, statistical analysis indicates that the diagnostic accuracy of the Gimenez stain, H&E stain, and PAS-AB stain were 95.6%, 91.1%, and 84.4% respectively. Gimenez stain is confirmed to be better than H&E stain and PAS-AB stain to detect H. pylori in 45 gastric biopsies of patients having gastritis. PAS-AB stain is the worst stain to detect H. pylori in gastric biopsies. Conclusion: Gimenez stain has higher diagnostic accuracy than PAS-AB stain in the detection of H. pylori in gastric biopsy. In fact, Gimenez stain has high sensitivity, specificity and diagnostic accuracy as compared to traditional H&E stain while PAS-AB stain has lower sensitivity, specificity and diagnostic accuracy. Thus, Gimenez stain is also recommended for the detection of H. pylori in gastric biopsy.