Comparison of a new office-based stool immunoassay and (13)C-UBT in the diagnosis of current Helicobacter pylori infection

Abstract

Noninvasive methods to diagnose the infection status of Helicobacter pylori were a new developed trend. In this study, the authors sought to investigate the difference between a new office-based stool immunoassay (ImmunoCard STAT! HpSA) and (13)C-Urea Breath Test ((13)C-UBT). We studied 254 dyspeptic patients (159 men, 95 women; mean age=52.8 +/- 14.3 years, range: 19--89 years). All of them underwent gastroendoscopy, (13)C-UBT test, and delivered stool samples within 3 days after endoscopy for the ImmunoCard STAT! HpSA test. The exclusion criteria were those who (1) had received previous anti-Hp treatment, proton pump inhibitor, antibiotics, or bismuth within 1 month of endoscopic examination; (2) had bleeding peptic ulcers; (3) had previously undergone gastric surgery; (4) had long-term use of corticosteroid or immunosuppressant drugs; (5) were pregnant or lactating; and (6) had incomplete data. Hp infection was considered positive when either culture was positive, or both histology and rapid urea test were positive. Those patients were classified as pre- and post-Hp treatment groups. Those in the post-treatment group were patients who received Hp eradication therapy at our hospital more than 2 months ago. The overall sensitivity, specificity, and positive and negative predictive values of (13)C-UBT and ImmunoCard STAT! HpSA were 96.3%, 87.6%, 85.4%, 96.9%, and 95.4%, 83.4%, 81.3%, 96.0%, respectively. The sensitivity, specificity, and accuracy of both tests are comparable in the pre- and post- treatment groups. The advantages of ImmunoCard STAT! HpSA over a breath test are that it is cheaper, more time-saving, and can be used in-office.