Enterohaemorrhagic Escherichia Coli (EHEC), Shiga- like Toxin Assay

Laboratory Fee Schedule
Procedure #: MAA0047A
CPT: 87427

Synonym(s):	Shiga- toxin producing, STX-1, STX-2, STEC, , E. coli toxin
Requisition Form	G-2B
Test Description	Escherichia coli Shiga toxin assay
Pre-Approval Needed	N/A
Supplemental Information Required	N/A
Supplemental Form(s)	N/A
Performed on Specimens from (sources)	Human
Sample/Specimen Type for Testing	Pure isolate of E. coli; Clinical stool
Minimum Volume/Size Required	Pure culture: At least one viable colony Clinical sample: At least 500 µl
Storage/Preservation Prior to Shipping	Pure Culture: • Keep isolates refrigerated at 2°C to 8°C. Broth/Liquid Transport Media: • Keep refrigerated if specimens will be received by Laboratory < 7 days after collection. • Keep frozen at -70°C if specimens will be received by Laboratory ≥ 7 days after collection.
Transport Medium	Appropriate media that support growth. Clinical specimens may be submitted in GN broth or in transport media.
Specimen Labeling	At least two patient-specific identifiers required on specimen (e.g., patient full name, date of birth, medical record number). Three unique patient identifiers are preferred. Patient identifiers on specimen label must exactly match identifiers on submission form (e.g., abbreviated name on label and full name on form is not acceptable.) Additional DSHS Laboratory specimen labeling guidelines available online here.
Shipping and Specimen Handling Requirements	• Ship according to Dangerous Goods Regulations, IATA, and/or CFR 49. • Category B Biological Substance, UN3373 shipping requirements apply. • Submitters are responsible for packaging and shipping specimens according to regulatory requirements. • Ship overnight on cold packs if specimens are refrigerated. • Ship overnight on dry ice if specimens are frozen. • Ship specimens overnight Monday–Thursday to avoid weekend deliveries. • Do not ship specimens for holiday or weekend delivery. • Ensure media used to isolate and ship clinical specimens or isolates are not expired. • Additional DSHS Laboratory specimen shipping guidelines online here.
Method	Enzyme Immunoassay
Turn-around Time	3–21 days
Interferences/Limitations	Isolates must be viable. Improper storage or shipping temperatures limit organism recovery.
Common Causes for Rejection	• insufficient quantity • unacceptable specimen type or source • improper shipping conditions • expired media or collection container • discrepancies between specimen label and submission form • incomplete or missing submission form
Additional Information	Shiga toxin-producing Escherichia coli infection (all E. coli O157:H7 isolates and any E. coli isolates or specimens in which Shiga toxin activity has been demonstrated (STX1, STX2) are required to be submitted per Texas Administrative code (TAC) chapter 97: §97.3(a)(4), §97.4(a)(6), and §97.5(a)(2)(C) Notifiable Conditions \| Texas DSHS