Clinical Use

• Differential diagnosis of patients with peptic ulcer disease and chronic active gastritis
• Therapeutic monitoring and documentation of cure in patients withH pylori infection

Clinical Background
H pylori is associated very strongly with peptic ulcer disease (duodenal and gastric) and chronic active gastritis. H pylori is also an independent risk factor for gastric cancer and primary malignant lymphoma of the stomach. The infection can be treated successfully with a combination of 3 drugs for 10 to 14 days.

This method detects H pylori antigen in stool specimens and can be used for diagnosis or therapeutic monitoring.

Interpretive Information
A positive result (antigen detected) is indicative of H pylori presence (96% sensitivity); however some individuals may have H pylori antigen but no disease.

A negative result (antigen not detected) indicates absence of H pylori or an antigenic level below the assay limit of detection (184 ng H pylori protein/mL of stool) (95.7% specificity). False negative results may be obtained on specimens from patients who have ingested selected compounds (antimicrobials, proton pump inhibitors, bismuth preparations) within 2 weeks prior to specimen collection. Physicians may suggest the patient go off medications for two weeks and repeat the test. Positive results are valid in the presence of medications. In populations with disease prevalence ranging from 34% to 69% (average 52%), the positive and negative predictive values were 96%.

A positive result ≥7 days post therapy is indicative of treatment failure.

A negative result ≥4 weeks post-therapy indicates eradication of the infection.

Specimen Requirements
1 gram stool