New monoclonal antibody-based test for Helicobacter pylori urease in gastric tissue

ABSTRACT

BACKGROUND/AIMS: To evaluate a new monoclonal antibody for Helicobacter pylori urease in gastric tissue. METHODS: A total of 107 volunteers were enrolled. All subjects underwent a 13C-urea breath test and esophagogastroduodenoscopy. Gastric aspirates were analyzed for pH and ammonia. Six biopsy specimens in the gastric antrum and body were obtained for a rapid urease test and histology. The new monoclonal antibody-based H. pylori urease test (HPU) was performed to rapidly and qualitatively detect urease in two biopsy specimens. RESULTS: H. pylori infection was diagnosed in 73 subjects. The sensitivity and specificity of the HPU was 89% and 74%, respectively. The subjects were divided into two groups one with true-positive and true-negative HPU results (n = 90) and the other with false-positive and false-negative HPU results (n = 17). Across all subjects, ammonia levels were 900.5 +/- 646.7 and 604.3 +/- 594.3 mumol/L (p > 0.05), and pH was 3.37 +/- 1.64 and 2.82 +/- 1.51 (p > 0.05). Sensitivity was higher in the presence of atrophic gastritis or intestinal metaplasia. CONCLUSIONS: HPU detected H. pylori in approximately 10 min. Gastric aspirate ammonia and pH levels did not affect the test results. Sensitivity was good in the presence of atrophic gastritis or intestinal metaplasia.