Stool Culture
Enteric Pathogens
Stool Culture for Enteric Pathogens
Last Updated: 04/01/2017
Procedure:
- The Specimen should be passed on a clean, dry surface such as a bed pan or collection cup. The specimen must not be taken from the toilet or contaminated with urine.
- Unscrew the Red cap from the Stool Culture Collection (ETM) vial.
- Using the collection "spork", collect scoops of stool specimen from areas of the stool that are bloody, slimy, or watery. (See notes below for watery vs. hard stools)
- Continue to add specimen to the bottles until the liquid reaches the red line.
- Mix the specimen THOROUGHLY with the spork and tightly twist cap to close.
- Mix container thoroughly and completely until there are no lumps
- Mix the spcimen thoroughly by stirring with the spork and tightly twist the cap closed.
- Mix container thoroughly and completely by shaking until there are no lumps.
- Be sure caps are tight.
- Label according to laboratory policy, and send to the laboratory at room temperature.
Note:
- The liquid in the Stool Culture Collection (ETM) vials is poisonous. Keep out of the reach of children and adults who might accidentally ingest!
- If the stool is formed or hard, take small scoops from the ends and middle of the specimen.
- If the specimen is watery, a protion can be carefully poured into the vials.
- Always check the expiration date printed on the vials before using.
- The specimen should be put into the preservative vials immediately after passage of specimen. The ETM vial will preserve all known enteric pathogenic bacteria for 72 hours.
- The stool collectionvials are stocked on the supply carts on the nursing units, Clinics and Outreach Centers. (Store room number: 900612)
Specimens Unacceptable for Stool Culture:
- Unpreserved stool samples >2 hours old.
- Preserved stool samples with yellow phenol red indicator, indicating failure of the buffering system to maintain a neutral pH and thus death of some organisms, especially Shigella spp.
- Dry rectal swabs (acceptable for screening for vanomycin-resistant Enterococci only)
- Multiple specimens collected on the same day.
- Stool cultures requested on inpatients who have been in-house greater than 3 days. These are of limited diagnostic value. Diarrhea developing three days or more after admission is most likely caused by C. difficile.
- Stool Preserved > 3 days old