Prospective evaluation of a new rapid urease test (Pronto Dry ®) for the diagnosis of Helicobacter pylori infection

Abstract

Rapid urease tests are commonly used to establish the diagnosis of Helicobacter pylori infection during upper endoscopy. The aim of this study was to evaluate the performance of a new rapid urease test (Pronto Dry) compared with histology as the gold standard. Six gastric biopsies (three in the antrum and three in the fundus) were performed in 113 consecutive patients. Eighteen patients were later excluded from analysis because they did not fulfil the inclusion criteria. Four biopsies were examined by two experienced pathologists blinded to the rapid urease tests. Two biopsies (one from antrum and one from the fundus) were pooled for the rapid urease test which was read by the endoscopist 5 and 30 minutes later using the color scale (yellow, pink, orange, dark pink, fuchsia) provided by the manufacturer. According to the histology findings 32 of the 95 patients retained for analysis (33.7%) were positive for Helicobacter pylori. Considering that a positive test was indicated by the dark pink or fuchsia colors, sensitivity and specificity of Pronto Dry were 62.5% and 98.4% at 5 minutes and 84.4% and 98.4% at 30 minutes respectively. Twenty-one of the 28 positive rapid urease tests (75%) were already positive at 5 minutes. Considering positive tests are indicated solely by the two darkest colors on the color scale, the performance of Pronto Dry is similar to that of other rapid urease tests. The rapid results provided by Pronto Dry in routine practice would seem to provide obvious advantages.