Escherichia coli(Hemorrhagic) Culture, Stool
Order in NUlirt or complete NPHL Test Order Form


Culture, Hemorrhagic E.coli; Culture, E.coli 0157: H7; Culture, Shigatoxin Positive E. coli


Standard reference procedure for confirmation of identification of an isolate for Hemorrhagic E.coli 0157:H7 by culture or isolation of E.coli O157:H7 in Positive Shiga toxin EIA stool.




Shigatoxin positive stool in enteric transport media preferred or pure culture of E.coli sorbitol-negative isolate on MacConkey or MacConkey Sorbitol plate for identification.  Positive Shiga EIA stool in enteric transport media, fill to line.

  Collection Device:

Sterile container or stool maintenance media 
Specimen Labeling: Test subject to CLIA regulations and requires 2 patient identifiers and specimen source on container.


10 mL stool in enteric transport media.


Prior to and during shipment:  Unpreserved stool at ambient 15-25°C; if transport delayed > 2h, preserve in enteric transport media (Cary-Blair media) at ambient 15-25°C up to 4d. 

Shipping instructions, including specimen-handling requirements during transport:  Seal screw-top tubes with Parafilm™ or tape and place in biohazard bag with absorbent material.
Place specimen inside leak proof secondary container (biohazard bag and if transporting by air, use Tyvek™ Envelope) with adsorbent material. The secondary container must be packed inside an approved Category B shipping container filled with frozen gel-packs to keep specimen refrigerated. Position NUlirt packing list or NPHL Test Order form between secondary container and box lid. Seal with tape.  Label outer box as UN3373 Category B, Biological Substance. Transport by NPHL ground courier. If courier not available, ship by FedEx, UPS, or USPS (1st Class, Priority or Express Mail). Follow appropriate DOT/IATA Regulation Guidelines.  For assistance, call NPHL State Training Coordinator at (402) 559-3590.  
See instructions and shipping address: http://nphl.org/

NUlirt packing list or appropriate paperwork (completed in entirety) must accompany specimens.


Non-sterile or leaking container, multiple specimens ( more than 1 in a 24 hour period), dry specimen, delayed transport to lab without use of appropriate preservative or red transport media indicator has turned yellow. Diapers are not acceptable.  Isolates submitted on blood agar plates may lose toxin expression and are therefore not preferred transport.

  Specimen Stability:

Unpreserved stool stable at Ambient 15-25°C < 2h, preserve in maintenance media at ambient 15-25°C up to 4 days

  Reference Interval:

Reported as soon as positive detected or Final: Negative at 2 days.

  Reportable Disease:

Report toxicogenic E.coli within 7d to local or state health department. Refer to Nebraska DHHS Title 173, Communicable Diseases.


Pre-approval needed from state or local health department.  Send approval to NPHL@unmc.edu or call (402) 559-9444.
Note: To test for Shiga toxin from E.coli in stool, see order for Stool Culture or Shiga Toxin EIA. 

NUlirt packing list or NPHL Test Order Form (completed in entirety) must accompany the specimen.

  Revised: 6/9/2021