Comparison of the diagnostic accuracy of the updated Sydney system and single biopsy.

Background: Updated Sydney system (USS) recommends taking biopsies from certain areas of the stomach for the diagnosis of precancerous lesions associated with Helicobacter pylori. Our aim was to evaluate the contribution of each of the biopsy sites to the diagnosis.

Methods: This prospective study included 97 patients aged 40 and over with dyspeptic complaints. Biopsies were taken from five regions: the lesser curvature of the antrum (LCA), the lesser curvature of the corpus (LCC), incisura angularis (IA), the greater curvature of the antrum (GCA), and the greater curvature of the corpus (GCC). Biopsy specimens were stained with hematoxylin-eosin stain, periodic acid Schiff-alcian blue, and Giemsa histochemical stain and evaluated according to the Sydney classification.

Results: Thirty-seven (38%) patients were positive for H. pylori in at least one biopsy site. Atrophic gastritis without intestinal metaplasia (IM) was found in 17 (17.5%) of the patients (6.2% in IA, 5.2% in each of LCA, GCA, and LCC, and 2% in GCC). The prevalence of atrophic gastritis with IM was 42.3% (21.6% in LCA, 20.6% in GCA, 20.6% in IA, 14.4% in LCC, and 5.2% in GCC). Endoscopic follow-up was planned in 21 (22%) patients due to the presence of extensive atrophy or incomplete IM. If a single biopsy of the LCA or a biopsy of both LCA and GCA was taken, endoscopic follow-up would have been missed in 12 (57%) or 6 (29%) patients, respectively.

Conclusion: Taking biopsies in accordance with the USS had higher sensitivity in detecting atrophic gastritis with or without IM compared to single biopsy. One or two biopsies is not sufficient to identify patients for whom endoscopic follow-up is recommended.