Helicobacter pylori with Clarithromycin Resistance Prediction, Molecular Detection, PCR, Feces
Use
The test is useful for aiding in the diagnosis of Helicobacter pylori infection and for predicting clarithromycin resistance or susceptibility directly from stool. H. pylori is a major cause of peptic ulcer disease and is a risk factor for gastric cancer. This test detects the Helicobacter pylori 23S ribosomal RNA gene and the most common gene variations leading to clarithromycin resistance, thereby helping in treatment decisions.
Special Instructions
For confirmation of eradication, testing should not be ordered until 4 weeks after cessation of treatment. Antibiotics should not be taken 4 weeks prior to testing, while proton pump inhibitors or bismuth compounds should be avoided 2 weeks before testing. Specimen collection requires a fecal sample in a specific transport medium to avoid contamination.
Limitations
A result indicating the presence of H. pylori DNA does not necessarily confirm active infection. False negatives could occur due to PCR inhibition, sequence variability, or insufficient DNA quantity. The test does not assess other clarithromycin resistance mechanisms or resistance to non-clarithromycin agents. Cross-reactivity may occur with nonpylori Helicobacter species that are not disease-causing in humans.
New York Approved
Methodology
PCR-based (RT-PCR)
Biomarkers
LOINC Codes
- 88509-5
- 91061-2
- 88509-5
- 31208-2
Result Turnaround Time
4-6 days
Related Documents
For more information, please review the documents below
Specimen
Stool
Volume
5 mL
Minimum Volume
1 mL
Container
Commercially available transport system specific for recovery of enteric pathogens from fecal specimens
Collection Instructions
Collect fresh fecal specimen and submit 1 gram or 5 mL in container with transport medium. Place feces in preservative within 2 hours of collection. Place vial in a sealed plastic bag and send ambient or refrigerated.
Patient Preparation
For 4 weeks prior to testing, patient should not take antibiotics. For 2 weeks prior to testing, patient should not take proton pump inhibitors or bismuth compounds.
Storage Instructions
Ambient (preferred) or refrigerated for 7 days.
Causes for Rejection
Fecal swab, Eswab transport medium, Feces in gel transport medium, ECOFIX preservative formalin, PVA fixative, Unpreserved stool
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 7 days |