Efficacy of immunohistochemical staining in detecting Helicobacter pylori in Saudi patients with minimal and atypical infection

Abstract

Background Gastric Helicobacter pylori infection is diagnosed based on histopathological evaluation of gastric mucosal biopsies, urease test, urea breath test, H. pylori culturing, or direct detection using polymerase chain reaction (PCR). This study aimed to evaluate the efficacy of immunohistochemical (IHC) staining in detecting H. pylori in gastric biopsies from dyspeptic patients with minimal and/or atypical infection. Gastric biopsies from 50 patients with chronic gastritis were subjected to routine haematoxylin and eosin (H&E), modified Giemsa, and IHC staining. The results of staining were compared with those of quantitative real-time PCR (qRT-PCR). Results The qRT-PCR analysis identified 32 (64%) H. pylori-positive cases, whereas IHC, H&E, and modified Giemsa staining identified 29 (58%), 27 (54%), and 21 (42%) positive cases. The false-positive rates of H&E and modified Giemsa staining were 16% and 14%, respectively. The sensitivity of IHC staining (87.50%) was higher than that of H&E (59.38%) and modified Giemsa (43.75%) staining. The specificity of H&E, modified Giemsa, and IHC staining was 55.56%, 61.11%, and 94.44%, respectively. IHC staining exhibited the highest diagnostic accuracy (90%), followed by H&E (58%) and modified Giemsa (50%) staining. Active gastritis, intestinal metaplasia, and lymphoid follicles were detected in 32 (64%), 4 (8%), and 22 (44%) cases, respectively, and all of these cases were H. pylori positive. Conclusions H. pylori can be detected using routine H&E or modified Giemsa staining. However, the high sensitivity, specificity, and diagnostic accuracy of IHC staining minimise the false-positive/negative results and enable H. pylori detection in cases with minimal or atypical infection. Moreover, IHC can be an alternative diagnostic method to qRT-PCR for detection of H. pylori in such cases.

The high sensitivity and specificity of rapid urease test in diagnosis of Helicobacter pylori infection in Moroccan children

“…Moreover, our laboratory used a simple stain method (hematoxylin and eosin) for its histological examinations, which may increase the number of false negatives in the gold standard. Nevertheless, two different staining methods should be used: hematoxylin and eosin for the assessment of inflammatory cells, and Giemsa for the determination of pathogens (17).…”

“…Histologic study. According to Zaitoun AM et al (17), the biopsy specimens collected for histology (one antral and one corpus biopsy) were fixed in 10% formalin, embedded in paraffin, and cut at 6 µm. Sections were stained with hematoxylin-eosin-saffron for light microscopy.…”