The diagnostic accuracy of gastric
urease activity for Helicobacter pylori (HP)
infection were studied in 98 patients with
peptic ulcer,
gastritis and
chronic renal failure. Gastric aspirates were analyzed for
urea nitrogen and
ammonia.
Urease activity was calculated as the ratio of gastric
ammonia to sum of gastric
urea nitrogen and
ammonia. Gold standard assessments to HP
infection were rapid
urease test, histology and/or culture. The results showed that the values of
urease activity in patients with HP
infection higher than that in patients without HP
infection. This were further assessed by eradication of HP. Sixteen patients with HP
infection were treated with
DeNol 330 mg/day for 4 weeks. HP was eradicated in 8/16 patients. In those cases
urease activity reduced (P < 0.05). If taken 0.31 as the cut-off index of
urease activity to diagnosis HP
infection, the sensitivity, specificity and accuracy were 95%, 84%, 93% respectively and were not affected by blood
urea nitrogen.