Enteric – Bacteria – Confirmatory Testing

Consistent with O. Reg. 671/92 of the French Language Services Act, laboratory testing information on this page is only available in English because it is scientific or technical in nature and is for use only by qualified health care providers and not by members of the public.

Testing Indications

Note to Submitters

Bacterial identification, confirmation and serotyping tests are applicable for Salmonella, Shigella, Campylobacter, pathogenic Yersinia, E.coli O157:H7 and non-O157 shiga toxin producing E. coli (STEC), Vibrio and other gram negative fermenting bacteria.

Specimen Collection and Handling

Specimen Requirements

Test Requested Required Requisition(s) Specimen Type Minimum Volume Collection Kit

Enteric bacteria identification

Pure viable subculture of organism on media that supports the growth1

None

Pure bacteria in appropriate agar plate, tube or swab for identification and speciation.

Submission and Collection Notes

1

Provide the name of the organism being submitted – Campylobacter, E. coli O157, non-O157 shiga toxin producing E. coli (STEC), Salmonella, Shigella, specific genus and/or species of Enterobacteriaceae, etc.

Limitations

Storage and Transport

Label the specimen container with the patient’s full name, date of collection and one other unique identifier such as the patient’s date of birth or Health Card Number. Failure to provide this information may result in rejection or testing delay.

Special Instructions

Specimens should be stored at 2-8°C following collection and shipped to PHOL on ice packs.

Requisitions and Kit Ordering

Test Frequency and Turnaround Time (TAT)

Enteric bacterial speciation is performed Monday to Friday.

Screening of non-O157 shiga toxin producing E. coli (STEC) is performed by polymerase chain reaction (PCR) twice a week.

Turnaround time is up to 10 days from receipt at the PHO laboratory.

Test Methods

Specimens are tested by conventional bacterial culture.
Bacterial identification includes Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF), biotyping and serotyping procedures.

Screening of non-O157 shiga toxin producing E. coli (STEC) is performed by PCR.

Antimicrobial susceptibility testing is routinely performed on Shigella and Vibrio.

Antimicrobial susceptibility testing is routinely performed on Salmonella Typhi, and Salmonella Paratyphi and for clinical indications (from blood or sterile sites, infants <1 year old, immuno-compromised patients and hospitalized patients–if documented).

Antimicrobial susceptibility testing on Campylobacter and Yersinia upon request only or for clinical indications (from blood or sterile sites, infants <1 year old, immuno-compromised patients and hospitalized patients – if documented).

Antimicrobial susceptibility testing on other bacteria is available upon request.

Reporting

Results are reported to the ordering physician or health care provider as indicated on the requisition.

Specimens that are positive for Salmonella, Shigella, Campylobacter, pathogenic Yersinia, E.coli O157:H7 and other shiga toxin producing E. coli, and Vibrio are reported to the Medical Officer of Health as per the Health Protection and Promotion Act.

References

LAB-SD-125, Reference Bacteriology and Antimicrobial Susceptibility: New Requisition and Testing Algorithm for Improved Test Utilization

Additional Information

For outbreaks, contact your local Health Unit, your local Public Health Laboratory or the Public Health Ontario, Public Health Laboratory Customer Service at 416-235-6555 or 1-877-604-4567.

Updated 25 Sep 2019