Helminth Ova, Stool Examination
Code:6001
| Includes | Diphhyllobothrium latum Ascaris lumbricoides Trichocephalus trichiurus Thominx aerophilus Ancylostomatidae genus sp. Fasciola hepatica Schistosoma mansoni Schistosoma japonicum Schistosoma haematobium Taeniidae genus sp. Hymenolepis nana Opisthorchis felineus Trichostrongylidae sp. Dicrocoelium lanceatum |
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Analysis details
Methodology
- Light microscopy
Expected Turnaround Time
1 day
Special Instructions
- Do not use laxatives, rectal suppositories, or mineral/castor oil for 72 hours before collecting the specimen.
- If clinically feasible, hold medicines that alter intestinal motility (eg, belladonna alkaloids, pilocarpine) for 72 hours prior to collection.
- Avoid substances that discolor stool—iron, bismuth, or barium sulfate—for 72 hours before collection.
How to use
Helminth Ova, Stool Examination (also called an O&P or stool ova and parasite exam) is used to identify helminth ova and larvae in stool in order to assess prolonged diarrhea and other gastrointestinal complaints in patients with epidemiologic risk factors. It is also used to document clearance or persistence of infection following antiparasitic therapy. Clinicians frequently order this test alongside other stool studies, such as bacterial culture, when nonparasitic causes of diarrhea are being evaluated and a broad differential diagnosis is needed.
Limitations
The examination relies on light microscopy of wet mounts or stained preparations of stool to recognize characteristic helminth ova and, when present, larvae. Many helminths have complex life cycles and can survive in the environment; transmission most often follows ingestion of contaminated food or water, though some species penetrate intact skin. Disease severity may be increased in young children, older adults, and immunocompromised patients. Common manifestations include prolonged diarrhea, abdominal pain, nausea, and occasionally fever; stool may contain blood and mucus. With sustained illness, weight loss, dehydration, and electrolyte disturbances can occur. Enterobius vermicularis eggs are not detected by this assay. When pinworm infection is suspected, a perianal adhesive tape test (Rabinovich method) should be performed.
| Unit | qualitative |
|---|---|
| Reference interval | — |
| Indications | Ongoing or recurrent diarrhea, Abdominal pain or cramping, Nausea or vomiting, Visible blood or mucus in the stool, History of contact with untreated surface water, Household or close exposure to someone with an intestinal helminth infection, Recent travel to endemic areas or developing countries, Follow-up after treatment of a confirmed helminth infection |
Specimen Requirements
| Specimen | Stool |
|---|---|
| Container | Sterile Stool Container |