The Pyloritek test and the CLO test: accuracy and incremental cost analysis

The aim of this study was to compare the Pyloritek test (a 1-h rapid urease test) to the widely used CLO test.

Seventy-one patients undergoing upper endoscopy were studied. All patients gave informed consent. A single antral biopsy specimen was obtained for the CLO test, and another was obtained for the Pyloritek test. Additional specimens were obtained for culture and processed in the event of a discordant result. The Pyloritek assay was read at 1 h by one observer. The CLO test was read at 24 h by an observer blinded to the results of the Pyloritek assay.

There were 18 males and 53 females, and the mean age (+/- SEM) was 53 +/- 17 yr. Thirty-two patients had a positive result on the CLO test, and 39 had a negative test result. Of the 32 patients with a positive CLO test result at 24 h, 31 were positive by the Pyloritek test at 1 h. All 39 patients with negative CLO test results had negative Pyloritek test results as well. There was one discordant result, a negative Pyloritek test result and a positive CLO test result. Culture demonstrated growth of Helicobacter pylori. The kappa value, a measure of the reliability of the Pyloritek test compared with the CLO test, was 0.972 (SE, 0.0284; 95% confidence interval, 0.925-1). Marginal cost-effectiveness analysis favored the Pyloritek test.

Results of the Pyloritek test at 1 h and the CLO test at 24 h are comparable in terms of detection of urease activity.