A Screening Trial of <b><i>Helicobacter pylori</i></b>-Specific Antigen Tests in Saliva to Identify an Oral Infection

Abstract

Objective:Helicobacter pylori infection places a heavy burden on medical and economic resources. Standard diagnosis requires the presence of established H. pylori gastric disease. Study Design and Setting: A multicenter screening trial assessing 2 immunochromatographic H. pylori antigen oral tests was carried out with 201 participants. The analysis also included a urea breath test (UBT), a Campylobacter-like organism test, silver stain, culture, serology, and stool tests. Results: The participants were grouped into UBT positive (UBT+) and UBT negative (UBT-) people, using conventional methods with congruent clusters based on p values from McNemar's paired χ² analysis and 95% CI estimates. Both oral tests were also positive in 82% of the seropositive UBT- people. However, oral antigen and seroprevalence divided UBT- people into 2 statistically separate CI subgroups: the UBT- symptomatic (highly positive) group and the UBT- asymptomatic (mostly negative) group. 90.5% of all people whose oral tests were both negative were also UBT-. Conclusions: Saliva H. pylori antigen is an important indicator in UBT- asymptomatic patients. Currently, its clinical significance remains uncertain, but saliva may be a reservoir from where H. pylori is transmitted to the stomach. In symptomatic patients, it is strongly associated with stomach infection.

A novel one-step Helicobacter pylori saliva antigen test

“…The analytical sensitivity of the test is 10 ng/mL of H. pylori urease. 17 There was no interference or cross reactivity with the other bacteria in the oral cavity and there was statistical correlation between oral antigen and serum antibody test results.…”

“…Several studies have suggested that oral H. pylori is associated with the presence of gastric H. pylori 14,15 infection, and patients who test positive for oral H. pylori have a lower success rate of gastric H. pylori eradication than oral H. pylori-negative individuals. 16,17 A search using PubMed found 305 articles that have "Helicobacter pylori" and "saliva" in the title, 26 titles that also include antigen in the title, and only three titles that are about detection of oral H. pylori antigen in humans.…”

“…The one-step HPS test is an immune-sandwich assay, highly sensitive to H. pylori urease, developed to use saliva as a specimen for detecting H. pylori colonization in the gastrological tract and oral cavity. 17 The monoclonal antibody used in the assay reacts with only H. pylori urease; thus, it has a high sensitivity and specificity. The analytical sensitivity of the test is 10 ng/mL of H. pylori urease.…”

“…It further identified those with no symptoms but with antigenic evidence of possible oral H. pylori infection who are thus at risk for developing gastric disease and recurrence infection. 16,17 It is a simple and rapid method to test for and eliminate oral H. pylori. This method can be used to prove the elimination of gastric H. pylori, and it is practical for use in the clinical environment as well.…”

Noninvasive diagnostic methods for Helicobacter pylori infection

“…9 Another study detecting H. pylori saliva antigen suggested that oral H. pylori infection continued to persist even though gastric H. pylori was already cured (negative UBT). 10 Yang et al's 2 study, in this issue, showed that the one-step H. pylori saliva antigen test exhibited a moderate sensitivity (71%) but low specificity (55%). The detection of H. pylori in saliva and dental plaque may precede or may be independent of gastric infection.…”