Evaluation of Four commercial Enzyme Immunoassay for Detection of Helicobacter pylori Infection

Eom, Hee Sub; Kim, Pum Soo; Lee, Jong Wook; Pai, Soo Hwan; Lee, Jin Woo; Choi, Won; Lee, Don Haeng; Kwon, Kye Sook; Cho, Hyeon Geun; Kim, Hyung Gil; Shin, Yong Woon; Kim, Yong Soo

Abstract

BACKGROUND/AIMS: Serologic methods for the diagnosis of Helicobacter pylori (H. pylori) infection are simple and inexpensive but have low sensitivity and specificity. We compared four different commercial kits commonly used in Korea for the diagnosis of H. pylori infection.
METHODS
Forty-one consecutive patients were involved in this study. They all underwent gastric endoscopy and biopsy. To detect H. pylori infection, the biopsy samples were analyzed by histology, culture, and CLO(TM) test and the results were used as a gold standard. We performed serologic tests including Bio-Rad GAP IgG, Radim H. pylori IgG, CLI H. pylori IgG ELISA, and Genedia H. pylori ELISA. The results were analyzed by receiver operating characteristic (ROC) curves.
RESULTS
In comparison with a predefined gold standard, the sensitivity of GAP(TM), Genedia(TM), Radim(TM), and Clarke(TM) was 60, 100, 88, and 68%, respectively. The specificity of the tests was 87.5, 81.3, 93.8 and 93.8%, respectively. The adjusted cut-off values using the ROC curves improved the performance of the tests.
CONCLUSIONS
Four serologic test kits commonly used in Korea are not different in the diagnostic accuracy for the detection of H. pylori infection, but ROC analysis can enable us to reexamine the validity of the cut-off valuse indicated by the manufacturers. Therefore, to optimize accuracy, the diagnostic performances of various serologic kits should be evaluated locally.