Comparison of stool antigen immunoassay methods for detecting Helicobacter pylori infection before and after eradication treatment.

The aim of the study was to compare 6 stool antigen immunoassays for detecting Helicobacter pylori before and after eradication treatment. We compared 3 enzyme immunoassay (EIA) and 3 monoclonal immunochromatographic assays in diagnosing infection and in determining H. pylori status after eradication treatment. We evaluated stool samples from 80 patients diagnosed with H. pylori infection and from 18 patients without infection. To confirm H. pylori eradication, we evaluated 40 patients who received H. pylori treatment. The sensitivity and specificity were 87.3% and 83.3% for Immundiagnostik ELISA, 92.5% and 72.2% for HpSA EIA test, 95% and 66.6% for HpStAR EIA, 83.8% and 66.6% for H. pylori Letitest, 52.5% and 94.4% for ImmunoCard HpSA, and 78.8% and 55.5% for RAPID HpStAR, respectively. From the 40 patients evaluated 6 weeks after eradication therapy, the best agreement between the urea breath tests and immunoassay tests was with HpStAR EIA (90%) and H. pylori Letitest (85%). HpStAR EIA and H. pylori Letitest could be used as a routine diagnostic tool in the microbiology laboratory for assessing clinical significance and eradication control of H. pylori infection.