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Test Code
POSTL
Test Name
Potassium, Stool
CPT Codes
84999
Expected Turnaround Time
5 - 10 days
Specimen and Container Info

Specimen Type: Random Stool

Alternate Specimen Type: 24 Hour Stool

Collection Container: Sterile Container

Alternate Collection Container: Timed Stool Collection Container

Desired Specimen Volume: 5 g
Collection Instructions
  1. Collect 24 hour or random stool in a sterile container (no preservatives).
Processing and Submission Instructions
  1. Do not add saline or water to liquefy specimen.
  2. Transport 5g of stool in the original collection container.
Transport Instructions

Transport to the laboratory refrigerated. 
Stability Requirements

Room Temperature

1 hour

Refrigerated

14 days

Frozen

6 months
Causes for Rejection
  • Formed or viscous stool
Methodology
Quantitative Ion-Selective Electrode
Reference Intervals

See patient report.
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Routine, daily
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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