New immunoassay for the detection of Helicobacter pylori infection compared with urease test, 13C breath test and histology: validation in the primary care setting.

Helicobacter pylori plays a major role in peptic ulcer disease and, as a result, testing for H. pylori infection among patients with dyspepsia has often been advocated. The aim of the study was to determine the diagnostic accuracy, the analytical performance, and optimal cut-off point of a new serological assay, the Pyloriset EIA-G III for the detection of H. pylori infection in the primary care setting. For 113 primary care patients with dyspepsia urea breath test, CLO test, histology and serology tests were performed. Diagnostic accuracy of the Pyloriset EIA-G III was evaluated against a reference standard of a carbon urea breath test (CUBT), CLO test and histology (from gastric biopsies). Precision, linearity and correlation of the serological assay with the CUBT and former Pyloriset were also determined. At the optimal cut-off level of 40 U/ml, the positive predictive value was 92.1%, negative predictive value 96.3%, sensitivity 87.5%, and specificity 93.9%. The within-run precision was high. The recovery data were good. The correlation of both CUBT and the former Pyloriset EIA-G and the Pyloriset EIA-G III was high. At the cut-off level of 40 U/ml, the new Pyloriset EIA-G III is a reliable method to detect H. pylori infection in the primary care setting.