# A Comparative Analysis of the Clinical Application of a Novel Helicobacter pylori Serum Antibody Typing Test and the 13C-Urea Breath Test

## TL;DR

This study compares two tests for Helicobacter pylori infection and finds that one test's accuracy depends on whether the patient has previously been treated for the infection.

## Contribution

The study introduces a novel serum antibody typing test for Helicobacter pylori and evaluates its diagnostic consistency compared to the 13C-urea breath test.

## Key findings

- The Hp-sATT detected more positive cases than the 13C-UBT, with distinct Type I and Type II infection classifications.
- Consistency between the Hp-sATT and 13C-UBT improved in patients without prior Helicobacter pylori eradication therapy.
- Hp-infected patients showed more severe gastric lesions, but Type I infections did not.

## Abstract

Background/Objectives: To compare and analyze the application of a Helicobacter pylori (H. pylori, Hp) serum antibody typing test (Hp-sATT) and the 13C-urea breath test (13C-UBT) in the diagnosis of Hp infection against an empirical therapy background. Methods: The detection of Hp-sATT using a combination of the quantum dot immunofluorescence method and the 13C-UBT was carried out in 237 patients who visited the Department of Gastroenterology at Beijing Tsinghua Changgung Hospital. The diagnostic consistency and correlation with gastric lesions of the two detection methods were analyzed by integrating the detection results, clinical information, and special staining of Hp in histopathological tissues (SS-Hp). Results: For the 13C-UBT, 104 (43.88%) cases were positive and 133 (56.12%) were negative. Positive results were found in 127 (53.59%) patients by using the Hp-sATT, with 67 (28.27%) cases of Type I Hp infection and 60 (25.32%) cases of Type II Hp infection. The consistency analysis between the Hp-sATT and 13C-UBT for all the patients showed a Kappa value of 0.339 (p < 0.001); the consistency analysis between the Hp-sATT and the 127 patients with SS-Hp showed a Kappa value of 0.427 (p < 0.001); and the consistency analysis between the 13C-UBT and the 127 patients with SS-Hp indicated a Kappa value of 0.621 (p < 0.001). However, in 191 patients without a history of Hp eradication, the consistency analysis results for the three methods improved, with Kappa values of 0.467 (p < 0.001) and 0.457 (p < 0.001) for the Hp-sATT with the 13C-UBT and SS-Hp, respectively, and 0.646 (p < 0.001) for the 13C-UBT with SS-Hp. In addition, a positive correlation was found between the signal values of anti-urease antibodies and the Delta Over Baseline (DOB) values of the 13C-UBT. The results also indicated that Hp-infected patients exhibited more pronounced gastric lesions, while cases with Type I Hp infection did not. Conclusions: In patients without a history of Hp eradication, the consistency between the Hp-sATT and 13C-UBT is moderate. However, Hp eradication therapy can reduce the consistency of the test results. When screening for Hp infection using the Hp-sATT, it is necessary to consider the patient’s history of Hp eradication.