Accuracy of the Ultra-Rapid Urease Test for diagnosis of Helicobacter pylori infection

Abstract

BackgroundRapid Urease Test (RUT) is a simple, cheap and relatively fast method for diagnosing Helicobacter pylori infection. It is therefore the preferred method used for patients undergoing gastroscopy. Most kits require 24h to give results. The new Ultra-Rapid Urease Test (URUT) kit by Biohit® requires less than 1h. ObjectiveTo determine URUT's diagnostic accuracy. MethodProspective, blind, multi-centre study involving dyspeptic patients. One corpus biopsy and three antral biopsies were obtained during gastroscopy for standard histological analysis, RUT and URUT. The URUT result was checked after 1min, 5min, 30min and 60min and the RUT was checked over the course of 24h. Histology was used as the gold standard test. Results144 patients were included, 68% female, with a mean age of 49 years old; 50% were H. pylori positive. RUT and URUT diagnoses were correct in 85.9% and 90% of the cases, respectively. The mean waiting time for a positive RUT result was 6h. The sensitivity, specificity, and positive and negative predictive values for RUT were, respectively, 82%, 90%, 89% and 84%. The URUT's results were similar (85%, 94%, 94% and 87%). These figures improved when patients taking PPIs were excluded (RUT: 86%, 91%, 93% and 83%; URUT: 91%, 94%, 96% and 89%). No statistically significant differences were found when comparing RUT and URUT distributions of correct diagnoses (McNemar's Test, p=0.3) but there was a tendency towards better results with the URUT. ConclusionThe URUT is equivalent to (or slightly better than) the traditional RUT in diagnosing H. pylori infection, and provides results in less than an hour.