The media of rapid urease test influence the diagnosis of Helicobacter pylori.

BACKGROUND/AIMS The influence of different media on the validity of the rapid urease test, including accuracy, reaction time and cost-effectiveness is evaluated. METHODOLOGY Biopsies were obtained from the antral and body mucosa of 100 KMUH patients (51 men, 49 women; mean age: 54.0 years, range: 21-79 years old) undergoing gastroendoscopy due to dyspepsia. None of the patients had received any Helicobacter pylori eradicating treatment, nor any other antibiotic or bismuth treatment in the previous one month, nor had they had any type of gastric operation in the past. Helicobacter pylori status was evaluated by seven different tests: culture, histology, home-made rapid urease test, 13C-urea breath test, and three different commercially available rapid urease tests--including the CLO test, the ProntoDry test, and the Pyloriset Urease test. Helicobacter pylori status was defined as positive when the culture was positive or if concordance of two of the other three tests (histology, homemade rapid urease test and 13C-urea breath test) was positive. RESULTS Three different rapid urease tests have similar sensitivities (97.3% vs. 100% vs. 100%) and specificities (98.4% vs. 96.8% vs. 98.2%), and accuracy (98.4% vs. 96.8% vs. 98.2%). But the reaction time was longer in the CLO test than for the other two rapid urease tests (22.3 vs. 5.6 vs. 10.1 minutes) (P < 0.05). The ProntoDry test and the Pyloriset Urease test also have more rapid positive rate than CLO test. However, in vitro study, three tests show similar rapidity of positive reaction at different densities of Helicobacter pylori. CONCLUSIONS These three tests have practical advantages for physicians who need a rapid and accurate method of diagnosing Helicobacter pylori infections. The ProntoDry test and Pyloriset Urease test have degrees of accuracy similar to the CLO test, but results are obtained more rapidly and they are cheaper. Furthermore, The ProntoDry test can be stored at room temperature and thereby save on the storage expense.