Objective: The aim of this study was to compare the diagnostic efficacy of common clinical tests to detect Helicobacter pylori infection, to evaluate the difference between antrum and corpus biopsy specimens on diagnostic tests and to investigate the effect of proton pump inhibitor use on the results of these diagnostic methods.

Materials and Methods: The presence of H. pylori infection was investigated by culture, rapid urease test and polymerase chain reaction (PCR) in antrum and corpus biopsy specimens and by ELISA in stool specimens of 100 patients. According to the gold standard criterion, patients whose culture was positive or in the case of negative culture, patients whose at least two tests out of three were positive were considered as H. pylori positive.

Results: In patients using proton pump inhibitors, the sensitivity and the specificity of culture, rapid urease test, PCR and ELISA were found to be 41-100, 77-92, 100-100, and 82%-100%, respectively,. In patients not using proton pump inhibitors, the sensitivity and the specificity of culture, rapid urease test, PCR and ELISA was found to be 74-100, 85-93, 100-100, and 96%-93% respectively.

Conclusion: Proton pump inhibitors decreased the sensitivities of all methods except PCR for the diagnosis of H. pylori infection and the difference was statistically significant for the culture method.