Effect of PPIs on Stool DNA Test for H. Pylori

Shanghai Jiao Tong University School of Medicine25 enrolled

Overview

This prospective, self-controlled clinical study aims to evaluate the impact of proton pump inhibitor (PPI) use on the accuracy of stool DNA testing for Helicobacter pylori (H. pylori) and to assess the applicability of this test in patients receiving PPI therapy. Patients requiring long-term PPI treatment and meeting the inclusion criteria were enrolled. After at least four weeks of PPI therapy, a stool DNA test was performed, along with collection of gastric mucosal samples via gastroscopy for tissue PCR, histology, and rapid urease testing, as well as H. pylori antibody detection. Subsequently, PPI treatment was discontinued for four weeks, after which a 13C-urea breath test and a repeat stool DNA test were conducted. By comparing the sensitivity, specificity, and consistency of stool DNA testing before and after PPI discontinuation, this study aims to characterize the interference of PPIs with the test results, thereby providing evidence to support improvements in H. pylori diagnostic methods.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Helicobacter Pylori Infection

Interventions

Proton Pump Inhibitor DiscontinuationDRUG

Participants underwent stool DNA testing and endoscopic evaluation after at least 4 weeks of continuous proton pump inhibitor (PPI) therapy. Subsequently, PPI treatment was discontinued for 4 weeks, after which a 13C-urea breath test and a repeat stool DNA test were performed. The intervention involves a 4-week washout period of PPI to assess its interference with stool DNA detection of Helicobacter pylori.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 80 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Male or female patients aged 18-80 years; * No prior H. pylori eradication therapy; * Patients requiring proton pump inhibitor (PPI) therapy in the near future due to gastritis, peptic ulcer disease, or other indicated conditions; * Patients with at least two positive results among H. pylori antibody test, histology, and rapid urease test (RUT); * Provision of signed informed consent and being informed of the specific study protocol. Exclusion Criteria: * Prior H. pylori eradication therapy; * Pregnant or lactating women; * Acute gastrointestinal bleeding; * History of subtotal gastrectomy; * Severe dysfunction of vital organs (heart, liver, kidney, lungs, etc.) or congenital diseases, such as class IV cardiac insufficiency, liver failure, uremia, respiratory failure, hemophilia, Wilson's disease, etc.; * Refusal of enrollment by the guardian or the patient; * Alcohol and/or drug abuse (addiction or dependence), or poor compliance as judged by the investigator; * Individuals without legal capacity or with impaired insight; * Abnormal neurological signs on physical examination; * Use of oral antibiotics with bactericidal activity against H. pylori within 4 weeks.

Outcomes

Primary Outcomes

Change in Diagnostic Sensitivity and Specificity of Stool DNA Test Before and After PPI Discontinuation

The sensitivity and specificity of stool DNA testing for Helicobacter pylori detection will be assessed under two conditions: (1) after at least 4 weeks of continuous proton pump inhibitor (PPI) therapy, and (2) after a 4-week PPI washout period. The reference standard comprises gastric mucosal biopsy results (histology, tissue PCR, and rapid urease test) combined with H. pylori antibody testing during the PPI-on phase, and 13C-urea breath test during the PPI-off phase. The primary outcome is the difference in sensitivity and specificity between the two conditions.

Time frame: Assessed at two time points: at baseline (after ≥4 weeks of PPI use) and at 4 weeks after PPI discontinuation

Secondary Outcomes

Inter-Method Agreement Among Diagnostic Tests

The level of agreement (kappa coefficient) among stool DNA test, gastric biopsy-based methods (histology, PCR, RUT), H. pylori antibody test, and 13C-urea breath test. This outcome assesses the overall concordance of diagnostic results across different testing modalities under varying PPI conditions.

Time frame: Baseline (for comparisons involving biopsy-based methods and serology) and 4 weeks after PPI discontinuation (for comparisons involving UBT)