Identification of Helicobacter pylori by different conventional staining techniques and its comparison with polymerase chain reaction

OBJECTIVE: To evaluate Helicobacter pylori (H. pylori) detection by histological staining methods, and to compare with those of Gram staining and polymerase chain reaction (PCR).

METHODS: This is a cross-sectional study conducted at the Department of Microbiology, Shree P. M. Patel Paramedical College, Anand, Gujarat, India on 436 patients attending the Deep Surgical Hospital, Anand, Gujarat between February 2008 and October 2011. Biopsies were subjected to histological staining using Hematoxylin & Eosin (H&E), Giemsa, and Warthin-Starry stains, as well as with Gram staining. The PCR was performed on 71 biopsy samples.

RESULTS: Sensitivity and negative predictive values of all 3 histological stains (Warthin-Starry, H&E, and Giemsa) were excellent. Gram staining showed excellent results pertaining to sensitivity, specificity, positive predictive value, and accuracy. Sensitivity of PCR was remarkably low compared to all the staining methods. The sensitivity of all histological stains was found better than PCR.

CONCLUSION: From the findings in our study, we conclude that in a mediocre laboratory, where PCR facility is not available, histological stain can be a better substitute for the diagnosis of H. pylori. Our findings also confirm the assertion that Gram staining is a preferred stain, affordable, reliable, and simple means for identifying H. pylori compared with both histology and PCR.