Evaluation of five commercial serological tests for the detection of Helicobacter pylori infection in Chinese

Background: Commercial serological tests for the detection of Helicobacter pylori infection must be locally validated. We evaluated the accuracy of fi ve commercial tests in the Chinese population. Methods: Serum samples were collected from patients referred for upper endo scopy. Antral biopsies were taken for histological examination and culture of H. pylori. The gold standard for diagnosing H. pylori infection was posi tive histological staining and/or positive H. pylori culture. The serum sam ples were tested for H. pylori antibodies using the following tests: (i) Co bas Core Anti-H. pylori EIA; (ii) GAP IgG; (iii) GAP IgM: (iv) H. pylori mi crowell EIA (Ouidel): and (v) Premier H. pylori. The sensitivity, specifici ty and accuracy of each test was calculated according to the manufacturers' instructions or according to a new cut-off value. Results: A total of 158 patients were recruited amongst whom 114 (72%) were H. pylori-positive. Indeterminate results varied from 7% to 19%. The accur acy of the tests varied from 57% to 85%. By using new cut-off values, the a ccuracy was much improved, ranging from 73.4% to 86.7%. Conclusions: By defining new cut-off values for the Chinese population, we were able to improve the performance of some of the serology tests. This il lustrates the importance of local validation.