PyloriTeK II for detection of Helicobacter pylori infection

Background: Rapid urease tests are commonly used as a convenient method to detect Helicobacter pylori infection. Our previous experiments demonstrated enhanced efficacy of agar gel rapid urease test compared to reagent strip rapid urease tests. We evaluated the efficacy of PyloriTek II (Serim Research Inc., Elkhart, IN), a new commercially available reagent strip rapid test, for detecting H. pylori infection. Methods: Gastric antral mucosal biopsies (jumbo forceps) were obtained from 100 patients for comparison between agar gel RUT and PyloriTek II (200 specimens). The rapid urease test to be used first was selected randomly. A warmer was used for the gel RUT. Biopsies obtained from a nearby area were stained using the Genta stain for determination of H. pylori status. Culture was performed to confirm H. pylori status when encountering a false rapid urease test. Results: Fifty of the 100 patients had peptic ulcer disease, 16 had dyspepsia; 31 had active H. pylori infection, and 3 had MALT lymphoma; 68 had H. pylori infection. There were two false negative and one false positive PyloriTek II when scored at 1 hour, compared to only one false positive and no false negative tests at 2 hours. While with agar gel RUT, there were no false positive tests and 5 false negative tests when scored at 1 hour and one at 24 hours; there were no false positive tests. The sensitivity and specificity's of PyloriTek II and agar gel RUTs were both >90% at 1 and 2 hours. PyloriTek II resulted in an erroneous categorization of H. pylori status and using PyloriTek occurred in 3% (95% C.I. = 1-9%) compared to 5% for agar gel RUTs (1.6-11%) at 1 hour (p>0.7). Conclusion: The new reagent strip rapid urease test, PyloriTek II is rapid and comparable in accuracy to the agar gel rapid urease tests for detecting H. pylori infection.