Optimal Sampling Site for the Diagnosis of Helicobacter pylori Infection with the Rapid Urease Test: A Prospective Cohort Study

Background/Aims: infection and identify the optimal gastric tissue acquisition site for RUT in clinical settings. Methods: We prospectively enrolled 377 patients who underwent esophagogastroduodenoscopy from December 2021 to June 2023. The diagnostic performance of the RUT of tissues from five gastric sites was evaluated using IHC as the reference standard. Performance was summarized by sensitivity, specificity, positive and negative predictive values, and Cohen's κ coefficient. Results: was detected by IHC in at least one of the five biopsy sites in 61.0% of the patients. Positivity was higher at the greater curvatures (GCs) than the lesser curvatures (LCs) of both the antrum and corpus for both tests. Among single-site tests, corpus-GC biopsy yielded the best diagnostic performance (sensitivity 0.89, specificity 0.78, κ=0.65). Multisite RUTs improved agreement; the combination of antrum-GC and corpus-GC showed the highest κ (0.70) and accuracy (0.86). When stratified by the Kimura-Takemoto atrophy classification, the antrum-LC and corpus-GC pair performed best in closed-type atrophy (κ=0.80), whereas antrum-GC and corpus-GC were superior in open-type atrophy (κ=0.66). Conclusions: The RUT demonstrated the highest diagnostic accuracy when performed at the GCs of both the antrum and corpus. A two-site biopsy approach at these locations is recommended to optimize diagnostic performance.