Usefulness of a Helicobacter pylori stool antigen test for diagnosing H. pylori infected C57BL/6 mice.

Among several diagnostic tests, a Helicobacter pylori stool antigen (HpSA) test may offer a useful noninvasive method for diagnosing infection without sacrificing animals. In this study, male C57BL/6 mice (n=6) were infected with H. pylori ATCC 49503 (1×10(8) CFU/mouse) by intragastric inoculation three times at 2-day intervals, and H. pylori infected stool specimens were collected 1, 3, 5, 7, 14, 21 days after infection to assess reliability of the HpSA test. Five of six specimens were positive at 5-21 days after infection, and the sensitivity of the HpSA test was 83.33%. The presence of H. pylori infection was confirmed by the rapid urease test and genomic DNA polymerase chain reaction (PCR), and showed the same results as the HpSA. However, the rapid urease test and genomic DNA PCR are invasive tests and require animal sacrifice to detect H. pylori in gastric biopsy samples. We suggest that an HpSA test kit would be useful and effective for monitoring H. pylori in various laboratory animals, as H. pylori can be easily monitored without sacrificing animals.