How proton pump inhibitors affect stool DNA testing for Helicobacter pylori

Effect of Proton Pump Inhibitors on Stool DNA Detection of Helicobacter Pylori: A Prospective Clinical Study

This study will test whether taking proton pump inhibitors changes the accuracy of stool DNA tests for detecting H. pylori in adults on long-term PPI therapy.

Quick facts

• Study type: Observational
• Enrollment: 25 (estimated)
• Ages: 18 Years to 80 Years
• Sex: All
• Sponsor: Shanghai Jiao Tong University School of Medicine (Academic / other)
• Locations: 1 site (Shanghai, Shanghai Municipality)
• Trial ID: NCT07516262 on ClinicalTrials.gov

What this trial studies

This is a prospective, self-controlled study enrolling adults on planned long-term PPI therapy who meet criteria for active H. pylori infection. After at least four weeks of PPI use participants provide a stool sample for stool DNA testing and undergo gastroscopy with tissue PCR, histology, and rapid urease testing plus antibody testing. Participants then stop PPI therapy for four weeks and receive a 13C-urea breath test and a repeat stool DNA test. The study compares sensitivity, specificity, and consistency of stool DNA testing before and after PPI discontinuation to characterize PPI interference with test results.

Who should consider this trial

Good fit: Adults aged 18–80 who need or are on long-term PPI therapy, have not had prior H. pylori eradication, and have at least two positive gastric H. pylori tests are ideal candidates.

Not a fit: Patients who have already undergone H. pylori eradication, are pregnant or breastfeeding, have severe organ failure, or cannot tolerate endoscopy are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, the results could help clinicians know whether stool DNA testing gives reliable results during PPI use and guide when to perform testing to avoid false negatives or positives.

How similar studies have performed: Prior work shows PPIs can suppress H. pylori and reduce sensitivity of breath and antigen tests, but the specific impact on stool DNA testing is less well studied and remains uncertain.

Eligibility criteria

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.

Where this trial is running

Shanghai, Shanghai Municipality

• Renji Hospital, School of Medicine, Shanghai Jiao Tong University — Shanghai, Shanghai Municipality, China (Recruiting)

Study contacts

• Study coordinator: Hong Lu, MD

Conditions Helicobacter Pylori Infection; Helicobacter pylori; Stool DNA Testing; Proton pump inhibitors