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Test Code
PTRYP
Test Name
Tryptophan, Plasma
CPT Codes
82131
Expected Turnaround Time
6 days
Specimen and Container Info

Specimen Type: Plasma

Collection Container: Lavender Top (EDTA)

Alternate Collection Container: Green Top (Sodium Heparin) or White Top (EDTA)

Desired Specimen Volume: 0.5 mL
Collection Instructions
  1. Collect a lavender top (EDTA) tube via venipuncture.
Processing and Submission Instructions
  1. Separate plasma from cells ASAP.
  2. Transfer 0.5 mL of plasma to a clear aliquot tube (screw cap) and freeze immediately.
  3. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.
Transport Instructions

Transport to the laboratory frozen. 
Stability Requirements

Frozen

14 days
Causes for Rejection
  • Gross hemolysis
Methodology
Chromatography/Mass Spectrometry
Reference Intervals

 See patient report.
Limitations

This test is NOT to be used for newborn screening.
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Monday-Friday
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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