Evaluation of two enzyme immunoassays for detecting Helicobacter pylori in stool specimens of dyspeptic patients after eradication therapy

The aim of the current study was to assess the reliability of two enzyme immunoassays in detecting the Helicobacter pylori status of stool specimens of Turkish dyspeptic patients in the post-treatment period. Forty-eight patients with non-ulcer dyspepsia who were positive for H. pylori underwent a 1 week regimen of triple therapy. Stool samples of patients were obtained 2 and 6 weeks after eradication therapy and a [13C]urea breath test was performed 6 weeks after therapy in order to assess the reliability of mAb-based (Amplified IDEIA HpStAR, DakoCytomation) and polyclonal-antiserum-based (Premier Platinum HpSA, Meridian Diagnostics) stool antigen test kits and to compare their diagnostic accuracies. Using a minimum cutoff OD450 value of 0.19 for Amplified IDEIA HpStAR and 0.16 for Premier Platinum HpSA the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of the tests were determined 2 and 6 weeks after completion of eradication therapy. At both the second and the sixth week in the post-treatment period the diagnostic accuracy of Amplified IDEIA HpStAR was significantly better than the Premier Platinum's (75% versus 50%, S2=6.4; P=0.011, and 90% versus 69%, S2=6.316; P=0.012, respectively). In light of these findings the mAb-based Amplified IDEIA HpStAR has a high diagnostic accuracy for H. pylori infection in Turkish dyspeptic patients 6 weeks after completion of eradication therapy.