ENTERIC BACTERIAL CULTURE & IDENTIFICATION

Laboratory: Microbial Reference

Test Description: Culture, identification, and additional characterization of enteric bacterial pathogens including, Salmonella species, Shiga toxin-producing Escherichia coli (STEC), Shigella species, Vibrio species, Vibrio cholerae, and Yersinia species (other than pestis)

Order Approval Required? No

Specimen Type:

• Stool in Cary-Blair Transport Medium
• Fecal or rectal swabs in gel transport media or in Cary-Blair Transport media
• MacConkey (MAC) or GN broth cultures (for STEC only)
• Pure bacterial isolate sent on slant or plate media, or on a transport swab or in Cary-Blair Transport media

Collection Container: Cary-Blair Transport Medium for submitting stool specimens

Optimal Volume: Enough stool sample should be collected to bring the Cary-Blair media level up to, but not exceeding, the fill line

Collection Guidelines:

• See Patient Instructions for Stool Collection
• • Instructions in additional languages are available on the following DCLS page: Sample Kit Collection and Shipping Stool specimens should preferably be collected before any antibiotic treatment is administered to the patient.
• Antibiotic therapy should be noted on the test request form.
• Instructions for the Submission of Stool Specimens

DCLS approved submitters can request collection kits at DCLS_SSSKits@dgs.virginia.gov.

Storage Instructions:

• Store Cary-Blair stools and fecal/rectal swabs at 2-30°C unless recovery of Shigella is required, in which case the specimen should be maintained at 2-8°C
• Cary-Blair stools and fecal/rectal swabs should be sent with minimal delay but must be received within 7 days of collection
• Store GN/MAC broth cultures at 2-8°C
• GN/MAC broth cultures must be received within 4 days of inoculation; broth tube must be labeled with date of inoculation
• Store isolates at 2-30°C

Transportation Instructions:

• Transport Cary-Blair stools and fecal/rectal swabs at 2-30°C unless recovery of Shigella or Campylobacter is required, in which case transport specimen at 2-8°C
• Cary-Blair stools and fecal/rectal swabs should be sent with minimal delay but must be received within 7 days of collection
• GN/MAC broth cultures transport: 2-8°C
• GN/MAC broth cultures must be received within 4 days of inoculation; broth tube must be labeled with date of inoculation
• Isolate transport: 2-30°C

Test Methodology: MALDI-TOF organism identification, conventional techniques; serology for Salmonella species, Shigella species and Vibrio cholerae; PCR detection of Shiga Toxins and Shigella species/Enteroinvasive E. coli

Causes for Rejection:

• Broken transport media
• Incorrect transport media
• Media that has expired prior to inoculation
• Evidence of exposure to temperature extremes during transport / Improper transport temperature
• Samples with no name or identifier, mismatched samples and test request forms
• Not enough or too much specimen in the Cary-Blair transport media
• True duplicate specimens (same collection date, source, and patient identifiers) may be rejected
• Specimen received out of the appropriate temperature range