Test for Helicobacter pylori Infection

Helicobacter pylori infection can be detected by several invasive tests based on gastroscopy and by noninvasive methods such as serologic assays. Noninvasive tests can be used not only in addition to invasive tests but also by themselves to screen for H. pylori infection in patients who are not in urgent need of endoscopy. Lately, rapid qualitative serologic tests have been developed. In the present study, the accuracy of a novel rapid whole-blood test, Pyloriset Screen, detecting immunoglobulin G (IgG) and IgA antibodies against H. pylori was evaluated. A total of 207 consecutive adult outpatients referred for upper endoscopy were enrolled. Gastric biopsy spec-imens were taken from the antrum and corpus for histologic examination and rapid urease testing. Cultures were available for 113 patients. Serum samples collected from all patients were tested for H. pylori antibodies by two enzyme immunoassays (EIAs) (Pyloriset EIA and an in-house EIA), a rapid latex agglutination test (Pyloriset Dry), and Pyloriset Screen. Patients were considered H. pylori positive if helicobacters were seen on histologic examination (77 patients) or, if in combination with histologically verified (although helicobacter-negative) gastritis, their IgG antibody titers were elevated in the two EIAs (five patients). The Pyloriset Screen test had a sensitivity of 95%, a specificity of 94%, a positive predictive value of 91%, and a negative predictive value of 97%. Among 63 patients under the age of 45 years, the Pyloriset Screen test did not miss a single H. pylori diagnosis, and only 1 patient had a false-positive result. Pyloriset Screen could be used reliably t