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Test Code
PHENM
Test Name
Phenylalanine Monitoring
CPT Codes
82131
Expected Turnaround Time
3 - 5 days
Specimen and Container Info

Preferred Specimen Type: Plasma

Preferred Collection Container: Green Top (Sodium Heparin)

Alternate Collection Container: Green Top (Lithium Heparin), Lavender Top (EDTA), White Top (EDTA)

Desired Specimen Volume: 0.5 mL
Collection Instructions
  1. Collect specimen in green top (sodium heparin) tube via venipuncture.
Processing and Submission Instructions
  1. Separate plasma from cells.
  2. Transfer 0.5 mL of plasma to a LabCorp pp transpak frozen purple tube.
  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
  • Room temperature or thawed specimens
  • Specimens collected in yellow-top (ACD) tubes
Methodology
Liquid Chromatography - Tandem Mass Spectrometry (Lc/Ms/Ms)
Reference Intervals

See patient report.
Limitations

This test is not to be used for newborn screening.
Alternate Names
  •  Phenylalanine, Quantitative, Plasma
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Varies
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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