What is the treatment for antral gastritis with a negative rapid urease test (RUT)?

Treatment of Antral Gastritis with Negative Rapid Urease Test

For antral gastritis with a negative rapid urease test (RUT), initiate empirical proton pump inhibitor (PPI) therapy at high doses (esomeprazole 20-40 mg or rabeprazole 20 mg twice daily, 30 minutes before meals) for 4-8 weeks, while recognizing that the negative RUT may be falsely negative if the patient was recently on PPIs, antibiotics, or bismuth. 1

Understanding the Negative RUT Result

The negative RUT does not definitively exclude H. pylori infection, as several factors can produce false negative results:

• Recent medication use: PPIs, antibiotics, and bismuth compounds temporarily reduce bacterial load and can cause false negative RUT results 2, 3

  • PPIs should be stopped for at least 2 weeks before testing 2, 3
  • Antibiotics should be discontinued for at least 4 weeks before testing 3

• Low bacterial density: The RUT requires approximately 10⁴ organisms for a positive result, and some patients harbor lower densities 2

• Technical factors: RUT sensitivity ranges from 80-95%, meaning up to 20% of infected patients may test negative 2

Initial Management Algorithm

Step 1: Assess Medication History

• If the patient was on PPIs, antibiotics, or bismuth within the past 2-4 weeks, the negative RUT is unreliable 2, 3
• Consider repeating H. pylori testing with a non-invasive method (urea breath test or monoclonal stool antigen test) after appropriate washout periods 1, 3

Step 2: Empirical PPI Therapy

Regardless of H. pylori status, initiate acid suppression for symptom relief and mucosal healing:

• First-line options 1:

  • Rabeprazole 20 mg twice daily
  • Esomeprazole 20-40 mg twice daily
  • Lansoprazole 30 mg twice daily

• Duration: 4-8 weeks initially 2, 1

• Timing: Take 30 minutes before meals for optimal effectiveness 1

Step 3: Consider Confirmatory Testing for H. pylori

If clinical suspicion for H. pylori remains high (persistent symptoms, history of peptic ulcer disease, or endoscopic findings suggestive of infection):

• Repeat non-invasive testing after proper medication washout 3:

  • Urea breath test (gold standard for non-invasive diagnosis) 1
  • Monoclonal stool antigen test 1

• If repeat testing is positive, treat with bismuth quadruple therapy for 14 days 1

• If repeat testing remains negative but symptoms persist, consider endoscopy with multiple biopsies from both antrum and corpus 3, 4

  • Biopsies from corpus are particularly important in patients on acid suppression, as H. pylori may migrate proximally 4
  • Use histology with special stains (immunohistochemistry is the gold standard) 2, 3

Special Considerations

For Patients on Acid Suppression Therapy

• H. pylori can migrate from the antrum to the gastric corpus during PPI or H2-blocker therapy 4
• Testing only the antrum may miss 8% of infections in patients on acid suppression 4
• If endoscopy is performed, obtain biopsies from both antrum and corpus 4

NSAID-Related Gastritis

If the patient has been taking NSAIDs:

• Use the lowest effective NSAID dose for the shortest duration 1
• Continue PPI therapy for gastroprotection 1
• Consider H. pylori eradication before starting long-term NSAID therapy if infection is confirmed 1

Response Assessment and Follow-Up

• If symptoms resolve with PPI therapy: Continue treatment for the full 4-8 week course 1

• If symptoms persist despite adequate PPI therapy:

  • Reassess for H. pylori with non-invasive testing after medication washout 3
  • Consider endoscopy to rule out other causes (malignancy, other forms of gastritis) 2, 1

• Antacids can be used on-demand for breakthrough symptoms 1

Common Pitfalls to Avoid

• Do not rely solely on a single negative RUT in patients with recent medication use or high clinical suspicion 2, 3
• Avoid inadequate PPI dosing or premature discontinuation of treatment 1
• Do not use serological testing to confirm or exclude active H. pylori infection, as it cannot distinguish between active infection and past exposure 3
• Avoid testing for H. pylori while patients are on PPIs or antibiotics, as this increases false negative rates 2, 3