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Ova and Parasite Exam

Item Value
Approval req'd? Contact Microbiology at x3-1268 for Stool O&P requests on inpatients > 72 hours after admission.
Available Stat? No
Test code P401
Test group Parasites
Performed by Microbiology
In House Availability Monday-Friday, day shift
Method Microscopy
Patient Preparation Patient should be off ALL antibiotics for ≥ 2 weeks before for an O&P examination to be valid.
Collection Instructions Collect 3 stool samples (one every 48 hours preferred, one per day is acceptable) to improve the chance of a positive result.

Aspirates submitted in a sterile container or leuken trap should be received in laboratory within 30 minutes of collection.
Container type Hepatic abscess aspirates: Sterile container

All other samples: SAF vial

SAF vials and instructions available from Material Services (PMM # 44366 Vials SAF Sterile Child Resistant Cap 574-05-CRC-WB).

Outpatients can obtain these from the laboratories' draw stations.
Amount to Collect See preferred volume
Sample type Stool; Duodenal/Colonic/Stool aspirates; Hepatic abscess aspirates
Preferred volume Stool: 10 mL (fill SAF vial to red line on container label)

Duodenal/Colonic/Stool aspirates: 15 mL

Hepatic abscess aspirates: 2 mL
Min. Volume 5 mL (2 mL for Hepatic abscess aspirates)
UCSF Rejection Criteria Unpreserved stool received > 1 hour after collection.
Stool in a preservative other than SAF.
More than one stool sample received within 24 hours.
Stool not mixed well in SAF, or if preservative has been poured out or is expired.
SAF container filled past the red line on the container label.
Processing notes Hepatic abscess aspirates: Put 1 ml of the specimen into a 15 ml centrifuge tube and add 2 parts SAF to 1 part specimen. Label tube as "SAF preserved." The remaining unpreserved aspirate should be refrigerated.

Transfer all other unpreserved samples to SAF preservative upon receipt in lab.

Do not reject unpreserved aspirates >1 hour post collection. Enter COMPRO in SREQ.

When receiving O&Ps by mail open each box individually. If necessary, label sample with patient name from information sheet in box. If information sheet is not filled out, give mailing container to parasitologist to investigate. If collection date is missing from specimens, accession each specimen and freetext note in SREQ "No collection date provided."
Normal range No parasites seen
Critical value Entamoeba histolytica in hepatic aspirate.
Synonyms Ova & Parasites; O&P; scolex; Protozoan concentration; Coccidia; Entamoeba histolytica
Stability Preserved: 2 weeks

Unpreserved: 1 hour (aspirates will be accepted >1 hour, but results may be compromised).
Turn around times 1-3 days
Additional information Includes concentration and iron-hematoxylin smear, and Kinyoun stain of unconcentrated sample for Cyclospora, Cryptosporidia, and Cystoisospora.

Aspirates are not acceptable for Giardia Antigen or Entamoeba histolytica antigen.

Also see entries for Giardia Antigen, Coccidia Exam, and Microsporidia.

For hepatic abscess aspirates: If the specimen is QNS to prepare stained smears, a wet mount alone will be done and procedure P412 charged.
CPT coding 87177, 88313, 87206
LOINC code 10704-5
Last Updated 1/25/2018 9:55:23 AM
Entry Number 719
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