Evaluation of a New Serologic Test for Diagnosis of Helicobacter pylori Infection in Children

Abstract

A new semiquantitative enzyme immunoassay (Platelia Helicobacter pylori; Sanofi Diagnostics Pasteur, France) was evaluated and compared with two other serological assays (Gap-test IgG; Bio-Rad, France; and Cobas Core; Roche, Switzerland) for the diagnosis of Helicobacter pylori infection in children. The three tests were compared with the examination of biopsy samples obtained from 160 dyspeptic subjects (mean age, 9 +/- 4.7 years). Discrepant results were studied using an immunoblot technique. The response obtained for the Platelia assay in children was significantly lower than that obtained in a previously described population of 92 adults (Helicobacter pylori-negative mean ratios, 0.376 vs. 0.504, P<0.000783; Helicobacter pylori-positive mean ratios, 1.95 vs. 2.67, P<0.000003). Thus, the optimal cut-off for children (0.80) was lower than the one recommended for adults (1.10). According to the Receiver Operating Characteristic (ROC) curve analysis and to the Wilcoxon value, the Platelia and Cobas Core assays showed the highest discriminatory properties (Wilcoxon value, 0.94 for both) compared with the Gap-test IgG (Wilcoxon value, 0.91). When the newly established cut-off value (0.80) was used, the performance of Platelia was equivalent to that of Cobas Core (sensitivity: 94.4% for each; respective specificities, 86.8% and 90.6%). The Gap-test IgG had a lower sensitivity (maximum, 79%) and a higher specificity (maximum, 95.3%), but there were difficulties in interpretation because its grey zone encompassed 12% of the sera. In conclusion, the results showed good performance of the Platelia Helicobacter pylori assay and confirmed the merit of a specific cut-off value for use of this test in children.

Antibody-Based Detection Tests for the Diagnosis of Helicobacter pylori Infection in Children: A Meta-Analysis

“…Of the 38 articles, 18 [52], [53], [56], [58], [59], [61], [62], [67], [69], [71], [73], [74], [76], [78], [79], [82], [85], [89] (47.5%) used culture and histological examination as the gold standard; ten [54], [60], [64], [70], [72], [80], [81], [83], [84], [87] (26.3%) used histology in combination with RUT and UBT; two articles [63], [68] (5.2%) used histology alone and seven articles [55], [57], [66], [75], [77], [86], [88] (18.4%) used UBT; and finally one article [65] (2.6%) used culture + UBT as gold-standard. For all articles the ELISA and WB tests did not form part of the reference standard.…”

“…Three papers in Spanish were included [62], [64], [76]. Thirty-one (81.5%) articles reported using a case-control design and the remaining seven [53], [57], [65], [66], [68], [69], [75] (18.5%) a cross-sectional design. Thirty-two of the 38 (84.2%) articles collected samples prospectively and six [53], [65], [66], [69], [74], [85] (15.8%) retrospectively; two [65], [75] (5.2%) articles reported the use of a randomly selected subset of the sample for validation with the reference standard.…”

“…Thirty-one (81.5%) articles reported using a case-control design and the remaining seven [53], [57], [65], [66], [68], [69], [75] (18.5%) a cross-sectional design. Thirty-two of the 38 (84.2%) articles collected samples prospectively and six [53], [65], [66], [69], [74], [85] (15.8%) retrospectively; two [65], [75] (5.2%) articles reported the use of a randomly selected subset of the sample for validation with the reference standard. Eleven [52], [61], [63], [64], [67], [68], [78]–[81], [83] (28.9%) articles reported at least single-blinded interpretation of the ELISA and WB tests and reference standard results, while 27 (71.1%) articles did not mention the blinding status.…”