Microscopic examination of stool for ova and parasites (O&P) using a qualitative probe
This test checks for the presence of worm eggs, protozoa, or other microscopic parasites in your stool. It helps identify infections that may cause symptoms like diarrhea, abdominal pain, or fatigue.
["A simple stool test to detect hidden intestinal parasites that could affect your health."]
Key facts at a glance
- LOINC
- 108218-9
- Short code
- E vermicularis DNA Spec Ql NAA+probe
- Synonyms
- E vermicularis DNA Spec Ql NAA+probe
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- probe-amp-tar
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your healthcare provider may recommend this test if you have symptoms like persistent diarrhea, unexplained weight loss, abdominal discomfort, or a history of travel to areas with higher parasite risks. It’s also used to diagnose or monitor conditions like giardiasis, amoebiasis, or pinworm infection.
What to Expect During the Test
You’ll provide a fresh stool sample in a container provided by your lab. The sample is then examined under a microscope to look for parasite eggs or organisms. Results are typically ready within a few days.
Common Parasites Detected
This test can identify eggs from worms like *Ascaris*, *Enterobius* (pinworm), *Trichuris*, or *Taenia*, as well as protozoa like *Giardia lamblia* or *Entamoeba histolytica*. Some parasites may not always show eggs, so repeat testing may be needed.
Preparation and Sample Handling
No special preparation is needed, but it’s important to submit a fresh sample (within 24 hours) for the most accurate results. If you’ve taken medications that could interfere, inform your lab staff.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Stool O&P (qualitative probe)
Frequently asked questions
Parasitic infections can cause chronic inflammation, malnutrition, or severe complications in some cases. Early detection helps prevent complications and guides treatment with antiparasitic medications.
Results are usually available within 2–5 business days, depending on lab processing times. If you have urgent symptoms, follow up with your provider to discuss next steps.
Yes, you can eat and drink normally before providing the sample. Avoid straining or using laxatives unless instructed by your provider, as this may alter the sample.
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy