New IgG blood test for H. pylori shows high specificity but limited sensitivity

Researchers have evaluated a domestically produced ELISA kit that detects IgG antibodies against Helicobacter pylori, and the results reveal a familiar trade-off in serological diagnostics: the new kit was the most accurate of four commercial and prototype assays at ruling out infection, yet it missed more true infections than its competitors.

The cross-sectional study enrolled 90 adults with dyspepsia who underwent upper gastrointestinal endoscopy. Using concordant results from two reference standards, the rapid urease test and histopathology, the investigators classified 48 patients as infected with H. pylori and 42 as uninfected. Serum anti-H. pylori IgG levels were then measured with four ELISA kits: the Sina Biotech kit under evaluation, along with Pishtazteb, Immunolab and Demeditec assays, and sensitivity and specificity were calculated for each.

The performance figures varied widely. The Pishtazteb kit showed 74 percent sensitivity and 70 percent specificity. The Immunolab kit achieved the highest sensitivity at 90 percent but the lowest specificity at 52 percent. Demeditec fell in between, with 84 percent sensitivity and 60 percent specificity. The Sina Biotech kit recorded the highest specificity of the group at 86 percent, but its sensitivity of 68 percent was the lowest reported in the comparison.

These numbers translate into distinct clinical roles. Because the Immunolab assay detected nine of every ten truly infected patients, it was the most effective at identifying infection, though its low specificity meant more than half of uninfected individuals would be flagged as positive. Conversely, the Sina Biotech kit, with its 86 percent specificity, was superior at correctly identifying people who were not infected, reducing false positives at the cost of missing roughly one in three true infections.

The authors conclude that the high specificity of the Sina Biotech kit makes it a cost-effective, locally produced serological tool for detecting H. pylori infection, particularly valuable in resource-limited settings where access to invasive diagnostics such as endoscopy is restricted, while its low sensitivity remains a clear limitation. The study’s scope should be kept in mind: it involved a single cohort of 90 dyspeptic adults, classification relied on concordant rapid urease and histopathology results, and the findings describe diagnostic performance in that setting rather than outcomes of patient care. The article was published as an open-access paper in BMC Microbiology on 27 October 2026, in a version shared early for faster access and subject to further editorial edits before the final Version of Record.

Subject of Research: Diagnostic performance of a new IgG ELISA kit for Helicobacter pylori compared with commercial kits and reference standards

Article Title: Diagnostic evaluation of a new IgG kit for Helicobacter pylori: comparison with commercial kits and gold standards

Article References: Shamsdin, S. A., Pouladfar, G., Samani, H., Fattahi, M. R., Nikmanesh, Y., & Kamyab, A. (2026). Diagnostic evaluation of a new IgG kit for Helicobacter pylori: comparison with commercial kits and gold standards. BMC Microbiology. https://doi.org/10.1186/s12866-026-05791-1

Image Credits: AI Generated

DOI: 10.1186/s12866-026-05791-1

Keywords: Helicobacter pylori, IgG antibodies, ELISA, diagnostic accuracy, sensitivity, specificity, serology, rapid urease test, histopathology, dyspepsia, BMC Microbiology, Diagnostic