How reliable are general histopathologists in detection of helicobacter pylori on routine histology ?

Abstract EN

Background: Many studies agree that routine histology is less sensitive and less specific than special stains and immunohistochemistry (IHC) with false‑positive and false‑negative rates.

Objectives: The aim was to evaluate the accuracy of four general histopathologists in documenting Helicobacter pylori (Hp) bacteria in gastric biopsies (stained with H and E) by using IHC and modified Giemsa stain (MG), also to assess the specificity of MG and whether it can replace IHC.

Materials and Methods: Twenty seven reported gastric biopsies were collected from each of four pathologists (9 reported as negative for Hp, 9 reported as scant Hp, and 9 as abundant Hp).

The pathologists selected were known to have different thresholds for Hp.

The biopsies were stained with MG and IHC and they were read by two pathologists.

Results: The four pathologists showed different thresholds for labeling luminal gastric pits' structures as Hp.

Overall, there were 5/36 false‑negative cases(13.9% ) and 26/72 false‑positive cases (36% ), most of them in the category reported as scant Hp detected.

The results of MG were concordant with that of IHC in 107/108 cases.

Conclusion: The overall accuracy rate of Hp detection on routine histology was 71% ; false positivity was much more common than false negativity, especially when only scant Hp reported to be present.

MG is a reliable stain and if done properly, it can replace the more costly IHC.

When Hp identification is crucial from the clinical management of view, special stains and/or IHC should be Background: Many studies agree that routine histology is less sensitive and less specific than special stains and immunohistochemistry (IHC) with false‑positive and false‑negative rates.

Objectives: The aim was to evaluate the accuracy of four general histopathologists in documenting Helicobacter pylori (Hp) bacteria in gastric biopsies (stained with H and E) by using IHC and modified Giemsa stain (MG), also to assess the specificity of MG and whether it can replace IHC.

Materials and Methods: Twenty seven reported gastric biopsies were collected from each of four pathologists (9 reported as negative for Hp, 9 reported as scant Hp, and 9 as abundant Hp).

The pathologists selected were known to have different thresholds for Hp.

The biopsies were stained with MG and IHC and they were read by two pathologists.

Results: The four pathologists showed different thresholds for labeling luminal gastric pits' structures as Hp.

Overall, there were 5/36 false‑negative cases(13.9% ) and 26/72 false‑positive cases (36% ), most of them in the category reported as scant Hp detected.

The results of MG were concordant with that of IHC in 107/108 cases.

Conclusion: The overall accuracy rate of Hp detection on routine histology was 71% ; false positivity was much more common than false negativity, especially when only scant Hp reported to be present.

MG is a reliable stain and if done properly, it can replace the more costly IHC.

When Hp identification is crucial from the clinical management of view, special stains and/or IHC should be requested.