Helicobacter pylori (HP) is an important etiological factor in chronic gastritis and duodenal ulceration. Demonstration of HP by means of culture and histological examination is relatively time-consuming. The object of this investigation was to assess the validity of two rapidly read chemical tests: the buffered urease reagent (BR) and the unbuffered urease reagent (UBR) in demonstration of HP among patients referred for gastroscopy on account of upper abdominal dyspepsia. In 230 sets of biopsies investigated for HP by culture and histology, the following results were obtained by reading of the BR test three hours later at room temperature: Nosographic sensitivity 0.54, nosographic specificity 0.97, PVpos 0.93 and PVneg 0.71. In another material consisting of 57 sets of biopsies, both BR and UBR were performed. Reading of UBR after 15 minutes yielded the following results: Nosographic sensitivity 0.56, nosographic specificity 1.00, PVpos 1.00 and PVneg 0.61. It is concluded that positive results of the urease tests indicate the presence of HP. If the urease tests are negative, supplementary culture and/or histological examination for HP should be performed. UBR is preferable rather than BR.
