An Alternative Method for a Rapid Urease Test Using Back-table Gastric Mucosal Biopsies from Gastrectomy Specimen for Making the Diagnosis of Helicobacter pylori Infection in Patients with Gastric Cancer

Kim, Sin ill; Jin, Sung Ho; Lee, Jae Hwan; Min, Jae Seok; Bang, Ho Yoon; Lee, Jong Inn

Abstract

PURPOSE
The rapid urease test is a rapid and reliable method for diagnosing Helicobacter pylori infection. However it requires gastric mucosal biopsies during endoscopy, and the test is not covered by national health insurance for patients with gastric cancer. So, we introduced an alternative method for a rapid urease test using back-table gastric mucosal biopsies from gastrectomy specimen.
MATERIALS AND METHODS
Ninety gastric cancer patients underwent an anti H. pylori IgG ELISA test and gastrectomy. Just after gastrectomy, two gastric mucosal biopsies from the prepyloric antrum and lower body of the gastrectomy specimen were taken from the back table in the operative room, and these were fixed immediately with the rapid urease test kit, and the color change was monitored for up to 24 hours. In this study, H. pylori infection was defined as positive when the serology or rapid urease test showed positive results.
RESULTS
The positive rate of the rapid urease test and serology was 91.1% and 77.8%, respectively. The sensitivity, specificity, positive predictive value and negative predictive value of the rapid urease test and serology were 94.3 and 80.5%, 100 and 100%, 100 and 100%, and 37.5 and 15%, respectively. The accuracy of the rapid urease test was higher than that of serology (94.4 vs. 81.1%, respectively). The rapid urease test showed a higher rate of detecting H. pylori infection than that of serology (McNemar's test, P=0.019).
CONCLUSION
The result of the rapid urease test using back-table gastric mucosal biopsies from a gastrectomy specimen is comparable to the reference data of the conventional rapid urease test using gastric mucosal endoscopic biopsies. Therefore, it can be an alternative diagnostic method for H. pylori infection.