Histology compared with chemical testing for urease for rapid detection of Helicobacter pylori in gastric biopsy specimens

Abstract

Gastric biopsy specimens from 283 patients with ulcer and non-ulcer dyspepsia attending five gastroenterology clinics in the northern region of the United Arab Emirates (UAE) were tested by the agar gel test (n = 115) or the ultrarapid endoscopy room test (n = 168) for the presence of Helicobacter pyloni urease. Results were compared with a histological technique using the Romanowsky type (Diff-3) stain for detecting H pylori in both antral and body type gastric mucosa. A sensitivity of 94%/O and specificity of 100% using the agar gel test compared with 87% sensitivity and 99*3% specificity for the ultrarapid endoscopy room test. Grading ofH pyloni in gastric biopsy specimens showed that the higher the histological grade, the more likely that the urease test would be positive. Both forms of urease tests have high specificity for detecting H pylon in gastric biopsy specimens, although the urea agar test has a higher sensitivity than the ultra-rapid test. Low numbers of H pylori in gastric biopsy specimens are the most important determinant of a false negative urease test.