Sensitivity of Helicobacter pylori detection by Giemsa staining is poor in comparison with immunohistochemistry and fluorescent in situ hybridization and strongly depends on inflammatory activity

Abstract

We highly recommend immunohistochemistry for clinically susceptible, nonactive chronic gastritis cases, if the conventional stain-based HP detection is negative. Moreover, we recommend to use IHC more widely as basic HP stain. Helicobacter pylori FISH technique is primarily recommended to determine bacterial clarithromycin resistance. Furthermore, it is another accurate diagnostic tool for HP.

Upfront immunohistochemistry improves specificity of Helicobacter pylori diagnosis. A French pathology laboratory point of view

“…The methods used for the detection of H. pylori in histopathologic samples must be in this manner sensitive and specific but also reproducible and cost‐effective. Albeit being widely applied, the interest of using ancillary stains as Giemsa and immunohistochemistry to detect H. pylori remains controversial . In this work, we intended to question about the place of these ancillary stains focusing on upfront immunohistochemistry based on a French pathology laboratory point of view.…”

“…Albeit being widely applied, the interest of using ancillary stains as Giemsa and immunohistochemistry to detect H. pylori remains controversial. 6,13,14 In this work, we intended to question about the place of these ancillary stains fo- In our experience, false-negative results can also arise with anti-H. pylori immunohistochemistry and caution is required searching for H. pylori based on this single test. In our study as in previous reports, the inter-rater agreement of H. pylori detection was better with ancillary stains especially using immunohistochemistry, which was also the method with the best performances.…”

“…Some argue for the use of immunohistochemistry as the basic stain searching for H. pylori to allow the detection of the bacteria even in biopsies with little to no inflammation whereas other guidelines advocate the contrary. 6,14 In our opinion, performing second-line immunohistochemistry in case of any minimal sign of chronic gastritis without obvious H. pylori infection on HE/HES-Giemsa stains could consist in a more reasonable approach, with little risk of clinically relevant underdiagnosis on the one hand and, in the other hand, little increase in the costs linked to H. pylori testing.…”

“…Then, we studied the inter‐rater agreement of H. pylori identification using the routine Hematoxylin‐Eosin Saffron (HES), Giemsa, and immunohistochemistry stains performed in our laboratory. Finally, we focused on the histologic features of biopsies with inconspicuous H. pylori infections in which histochemical stains often lead to misidentification of H. pylori; we intend to discuss the necessity of using immunohistochemistry “up front” on all gastric biopsies independently of HE/HES results or as a second‐line analysis in function of first HE/HES result …”

“…Finally, we focused on the histologic features of biopsies with inconspicuous H. pylori infections in which histochemical stains often lead to misidentification of H. pylori; we intend to discuss the necessity of using immunohistochemistry "up front" on all gastric biopsies independently of HE/HES results or as a second-line analysis in function of first HE/HES result. 14…”