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

Laboratory Fee Schedule
Procedure #:  MAA0047A
CPT:    87427

Synonym(s):  Shiga-like toxin, STX-1 STX-2, STEC, EHEC, 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 culture E. coli; Clinical stool
Minimum Volume/Size Required Pure culture: At least one viable colony
Clinical sample: 500 µl
Storage/Preservation Prior to Shipping Pure Culture: 
  • Refrigerated
Broth/liquid transport
  • Refrigerated: Received < 7 days
  • Frozen @-70C: Received > 7 days
Transport Medium
  • Media supporting growth of isolate
  • Clinical sample in GN broth or transport media
Specimen Labeling
  • Two patient-specific identifiers required (e.g., patient full name, date of birth, Medical record number)
  • Identifiers on specimen must exactly match submission form.
Shipping and Specimen Handling Requirements
  • Ship according to Dangerous Goods Regulations, IATA, and/or CFR 49.
  • Ship specimens overnight Monday-Thursday, to avoid weekend deliveries.
Method Enzyme Immunoassay
Turn-around Time 3-21 days
  • Material 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)   https://www.dshs.state.tx.us/idcu/investigation/conditions/