[Diagnosis of Helicobacter pylori infection on gastric biopsies: Standard stain, special stain or immunohistochemistry?].

INTRODUCTION

There is no consensus on the benefit of performing a systematic complementary technique for the diagnosis of Helicobacter pylori infection. In our laboratory, a cresyl violet was carried out systematically until July 2014; since that date, a cresyl violet or immunohistochemistry is only made on request. We evaluated the value of cresyl violet staining of gastric biopsies to diagnose H. pylori infection by comparing a period of systematic staining to a time when it was made on demand.

MATERIAL AND METHODS

We retrospectively studied the gastric biopsy of 786 consecutive patients from April to November 2014, taken in the absence of focal endoscopic lesion. During the first period, hematoxylin-eosin and cresyl violet were performed on all biopsies. During the second period, hematoxylin-eosin was performed and then, if necessary, cresyl violet or immunohistochemistry. All hematoxylin-eosin stained slides were revised to identify H. pylori. We performed immunohistochemistry in cases of active chronic gastritis without H. pylori identified on hematoxylin-eosin or cresyl violet.

RESULTS

We have shown that gastric biopsy performed in the absence of focal mucosal lesion are normal in 55% of cases. The percentage of H. pylori infection was similar in both groups. In cases of active chronic gastritis, H. pylori infection is visible, in most cases, on hematoxylin-eosin (94%). Immunohistochemistry should be prescribed only in case of chronic active gastritis without H. pylori identified on standard staining, with bacteria rare or atypically located.

CONCLUSION

In our experiment, H. pylori is present only in case of active gastritis (33% of the biopsies in our series) and being almost always identifiable on the standard staining with H-E (in 94% of the cases), it is not It is not necessary to systematically perform, on all gastric biopsies, a complementary histo- or immunohistochemical technique.