Two Enzyme Immunoassays and PCR for Detection of Helicobacter pylori in Stool Specimens from Pediatric Patients before and after Eradication Therapy

Abstract

This study of pediatric patients was intended to determine the suitability of stool PCR and two antigen enzyme immunoassays (EIAs; Premier Platinum HpSA and the novel FemtoLab H. pylori), which detectHelicobacter pylori antigens in feces, as pretreatment diagnostic tools and especially as posttreatment control. Forty-nineH. pylori-infected children with dyspepsia received eradication therapy. Successful treatment was determined by a negative [13C]urea breath test 4 and 12 weeks after discontinuation of therapy. Fecal specimens were collected prior to eradication therapy as well as 4 weeks after the end of treatment. Successfully treated children delivered stool samples at 6, 8, and 12 weeks posttreatment also. Specimens were examined by seminested PCR and Premier Platinum HpSA and were reexamined by both EIAs as soon as FemtoLab H. pylori was available. In the first test series, the overall sensitivities of PCR and Premier Platinum HpSA were 93.0 and 91.1%, respectively. With specimens collected at 4 weeks after treatment, the respective specificities were 68.8 and 79.3%. After longer follow-up periods, however, they gradually increased to 100 and 96.9%, respectively. In the new test series, Premier Platinum HpSA delivered a considerably lower number of false-positive results (4 versus 18), indicating intertest variations. The overall test sensitivity was 94.6%, and the overall specificity was 97.5%. FemtoLab H. pylori showed an excellent performance with an overall sensitivity and specificity of 98.2 and 98.1%, respectively. Thus, in contrast to PCR, both EIAs were shown to be suitable for early posttreatment control.

Multicenter Comparison of Rapid Lateral Flow Stool Antigen Immunoassay and Stool Antigen Enzyme Immunoassay for the Diagnosis of Helicobacter pylori Infection in Children

“…In the EIA method with polyclonal antibodies, indeterminate absorbance values, a gray zone, is set up according to the manufacturer's instruction, although indeterminate cases are rare [8,9,18]. It has been reported that the HpSA EIA test can be performed using a single cut-off value with an absorbance of 0.110 at 450/ 630 nm, which is located within a gray zone [5,9]. However, the selection of an appropriate cut-off value for the EIA method is still a matter of debate [18,19].…”

“…Clearly, larger studies are needed. In adults [18,20] and children [5,9,21], there are reports that the HpSA EIA method is useful to assess H. pylori eradication. However, several studies have suggested that the HpSA EIA is less reliable than [ 13 C]UBT in the assessment of H. pylori eradication [22,23] and the Maastricht 2-2000 consensus conference recommended [ 13 C]UBT as the most reliable, noninvasive test to assess eradication efficacy [13].…”

“…H elicobacter pylori infection is associated with the development of chronic gastritis, peptic ulcer disease, gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma and has been implicated in the pathogenesis of many extragastric diseases, ranging from atherosclerosis to skin diseases, although the association is controversial [1]. Among noninvasive tests for the diagnosis of H. pylori infection, the 13 C-labelled urea breath test ([ 13 C]UBT) [2 -4] and the stool antigen tests using enzyme immunoassay (EIA) with polyclonal antibodies [5][6][7][8][9] have shown good diagnostic accuracy in children and adolescents. Recently, another stool antigen test using monoclonal antibodies has also been reported to have excellent test performances [5,10,11].…”

“…Among noninvasive tests for the diagnosis of H. pylori infection, the 13 C-labelled urea breath test ([ 13 C]UBT) [2 -4] and the stool antigen tests using enzyme immunoassay (EIA) with polyclonal antibodies [5][6][7][8][9] have shown good diagnostic accuracy in children and adolescents. Recently, another stool antigen test using monoclonal antibodies has also been reported to have excellent test performances [5,10,11]. A metaanalysis demonstrated that the [ 13 C]UBT and the stool antigen test were both highly sensitive and specific [12] and the European Helicobacter pylori Study Group [13] has recommended both noninvasive tests for diagnosing H. pylori infection.…”

Novel Monoclonal Antibody‐Based Helicobacter pylori Stool Antigen Test

“…The monoclonal antibodies used and the technical features of the kit employed might be further improved to enhance the sensitivity of the test. The greater performance of the tests employing monoclonal antibodies compared to the tests employing polyclonal antibodies has recently been reported [5,7]. Leodolter et al reported that in the post-treatment setting the sensitivity of FemtoLab H. pylori test was higher than that of the Premier Platinum HpSA assay (94.3% vs. 80%), although not statistically significant [5].…”