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Bacterial Culture, Stool
|Approval req'd?||Yes, consultation required for samples submitted > 72 hours after inpatient admission. Contact Microbiology at x31268|
|Test group||Bacterial Culture|
|In House Availability||Set up daily on day and evening shifts|
|Collection Instructions||Submit stool in a cup with a screw-on lid within 3 hours of collecting the specimen. Alternatively, using Cary-Blair collection vial, add stool to red line and mix well with a spoon (see below).
Two specimens collected 24-48 hours apart are sufficient for the detection of the great majority of pathogens.
Vials containing Cary-Blair transport medium for stool specimens which cannot be inoculated by the laboratory within 3 hours of passage can be obtained from ACC phlebotomy stations at A 122 or A 220A or from the Emergency Dept. (e.g., specimens to be collected at home or after midnight, when the Microbiology Department is closed)
|Container type||Collection cup, or Cary-Blair transport media|
|Amount to Collect||8 gm or 8 mL|
|Preferred volume||8 gm or 8 mL|
|Min. Volume||8 gm or 8 mL|
|UCSF Rejection Criteria||Unpreserved stool received > 3 hours after collection. More than two samples per episode or more than one sample received within 24 hours|
|Processing notes||Maintain sample at room temperature|
|Critical value||Stools positive with E. coli O157:H7, Vibrio cholerae or Salmonella sp. that cause enteric fever (e.g. S. typhi). Stools positive for Shiga toxin producing E.coli.|
|Synonyms||Salmonella; Shigella; Campylobacter; Vibrio|
|Stability||Unpreserved 3 hours, preserved 1 week.|
|Turn around times||3-5 days|
|Reflex?||If bacteria are detected that are not normal mixed flora they are automatically identified and susceptibility testing is performed if appropriate.
Full ID and/or susceptibility testing may be omitted upon request when sample is submitted for testing.
If stool is visibly bloody or the box for 'bloody stool' is checked on the Microbiology requisition, media to detect E. coli 0157:H7 will automatically be set up.
If E.coli O157 is detected the isolate is automatically referred to SFPH to determine if the strain is a toxin producer.
|Additional information||Unusual findings such as the absence of normal gram-negative enteric flora are reported.
If suspected, E. coli O157 [P157], Yersinia species [P158] and Vibrio species [P159] must be requested separately to ensure that selective media are inoculated, However, if the sample is bloody or the 'bloody stool' box is checked on the Microbiology requisition the media to detect E. coli 0157 will be set up automatically.
For followup of a culture positive for Salmonella order a culture for this organism only [P156].
C. difficile is not cultured. If C. diffile is supected request the C. difficile antigen assay (P328).
|CPT coding||87045, 87046|
|Last Updated||10/2/2010 11:51:24 AM|
If you have additional questions regarding this test, please call: 415-353-1667