New Test for H pylori Evaluation

Helicobacter pylori infection is linked toapproximately 80% and 90% of gastric andduodenal ulcers, respectively. The H pyloristool antigen (HpSA) test is a new tool forevaluating infection. In a recent study, reportedin the Journal of Gastroenterologyand Hepatology (August 2005), MasanoriIto, MD, and colleagues investigated theclinical usefulness of the HpSA test, comparedwith the ¹³C-urea breath test (UBT), inevaluating bacterial eradication therapy.Patients (n = 105) with H pylori infectionreceived appropriate antibiotic eradicationtherapy (eg, amoxicillin, tetracycline), andthe results were evaluated after 8 weeks.

Of these patients, 24% and 19% testedpositive with the UBT and the HpSA test,respectively. Discordant results were seenin 8.6% of the patients (7 with UBT+ andHpSA-and 2 with UBT-and HpSA+). Fiveof the patients were determined to havefalse-positive results with the UBT. Finaldiagnostic accuracies of the UBT and theHpSAtests were 94.3% and 97.1%, respectively.In cases of weakly positive UBT values,the HpSA test was used to diagnosethe correct status of infection after eradicationin 99% of all patients. For the clinicalevaluation of eradication therapy, a combinationof both tests is recommended.