Gastrointestinal Pathogens Stool PCR-Parasite - Provincial
Discipline
Microbiology
Overview
Description
- Parasite stool PCR is a multiplex, real-time PCR assay for direct detection of nucleic acid from parasites causing infectious gastroenteritis. This assay detects only the most common protozoan parasites transmitted by contaminated water or food including Giardia lamblia, Crytosporidium spp. (parvum and hominis) and Entamoeba histolytica.
Ordering Recommendations
- Patients with acute diarrheal syndromes and signs of infection consistent with parasites
- Patients hospitalized for 3 days or less
- Patients associated with Cryptosporidium outbreaks
- Symptomatic patients with known exposure to contaminated lake water
- Patients with travel history consistent with Entamoeba histolytica
- This test is not recommended as a test of cure
- Repeat PCR testing not indicated within 7 days of a negative or 14 days of a positive result
- Ova and Parasite exam is still required for other parasitic causes of diarrhea including Cyclospora spp., Cytoisospora spp., Microsporidium spp., nematodes (round worms), cestodes (tape worms) and trematodes (flat worms)
Specimen Information
Specimen types accepted
- Stool in Cary-Blair transport media (Enteric Culture Transport Media)
- Rectal swabs are NOT accepted
Collection procedure
- Do not let urine or water mix with stool specimen
- Do not use toilet paper to collect stool
- You will need a separate, sterile disposable container to collect stool prior to placing inside Cary-Blair transport media. Using the plastic paddle attached to the lid of the Cary-Blair tube, collect small portions from each end and the middle of the stool, especially sampling areas of stool that contain mucus or blood
- Place solid stool about the size of a walnut into the Cary-Blair vial or sterile container
- Fill liquid stool to the fill indicator line on the container. DO NOT FILL PAST THIS MARK.
- Place cap on container securely.
- Ensure outside of container is not contaminated with stool.
- Wash hands with soap and water.
Required volume
- 1 stool specimen
- Recommended walnut sized solid stool or to Cary-Blair fill line for liquid stool
Transport and stability
- Store at 2-4 °C and transport without delay
- Specimen should be received by lab within 48h of collection
- Specimens older than 4 days will be rejected
Testing Information
Relevant clinical history
- If patient is part of an outbreak, include the outbreak number
- Patient should not take any laxatives, enemas or antibiotics for 1 week prior to specimen collection
- Consider C. difficile testing with new onset diarrhea from patients hospitalized greater than three days
Performance
Methodology
- BD Max Enteric Viral PCR Panels
Days/times performed
Availability
- Test performed 7 days per week
Maximum laboratory time
Result Reporting
- 24-48h turnaround time for PCR
Specimen retention time
- Specimens are retained for 3 days after initial processing
Other information
Any additional comments
- Specimens requiring microscopic Ova and Parasite exam should be submitted with separate, appropriate collection media and a Parasitology History Sheet
- No patient history or incomplete patient history provided will result in ONLY a screen for Giardia, Cryptosporidium, and Entamoeba histolytica (one specimen per 7 days) being performed
Last Updated: April 17, 2024