Phenylalanine and Tyrosine

Test Code

26336

CPT Code(s)

84030, 84510

Test Code

26336

CPT Code(s)

84030, 84510

Not offered in Quest Diagnostics Nichols Institute (IFD) – San Juan Capistrano. Please provide SERVICE AREA INFORMATION to find available tests you can order.

In-home collection is not available in your area through Quest Mobile.

Clinical Significance

Phenylalanine and Tyrosine

Test Resources

None found for this test
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Test Details

Patient Preparation

Collect specimen after an overnight fast (or at least 4 hrs after a meal) if possible. Non-fasting samples are acceptable for pediatric patients.

Methodology

Chromatography/Mass Spectrometry

Assay Category

This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Reference Range(s)

⁠⁠⁠⁠⁠⁠⁠Phenylalanine

≤30 days	30-79 umol/L
31 days-23 months	31-92 umol/L
2-17 years	38-86 umol/L
≥18 years	40-74 umol/L

Tyrosine

≤30 days	33-160 umol/L
31 days-23 months	24-125 umol/L
2-17 years	31-108 umol/L
≥18 years	38-96 umol/L

LOINC® Codes, Performing Laboratory

Service Area must be determined

Patient Preparation

Collect specimen after an overnight fast (or at least 4 hrs after a meal) if possible. Non-fasting samples are acceptable for pediatric patients.

Methodology

Chromatography/Mass Spectrometry

Assay Category

Reference Range(s)

⁠⁠⁠⁠⁠⁠⁠Phenylalanine

≤30 days	30-79 umol/L
31 days-23 months	31-92 umol/L
2-17 years	38-86 umol/L
≥18 years	40-74 umol/L

Tyrosine

≤30 days	33-160 umol/L
31 days-23 months	24-125 umol/L
2-17 years	31-108 umol/L
≥18 years	38-96 umol/L

LOINC® Codes, Performing Laboratory

Service Area must be determined

Preferred Specimen(s)

0.4 mL plasma collected in a sodium heparin (green-top) tube

Alternative Specimen(s)

Plasma collected in: EDTA (lavender-top) or lithium heparin (green-top) tube

Minimum Volume

0.2 mL

Collection Instructions

Separate plasma from cells as soon as possible and freeze below -20° C

Transport Container

Transport tube

Transport Temperature

Frozen

Specimen Stability

Room temperature: Unacceptable
Refrigerated: 7 days
Frozen: 28 days

Setup Schedule

Service Area must be determined

Preferred Specimen(s)

0.4 mL plasma collected in a sodium heparin (green-top) tube

Alternative Specimen(s)

Plasma collected in: EDTA (lavender-top) or lithium heparin (green-top) tube

Minimum Volume

0.2 mL

Collection Instructions

Separate plasma from cells as soon as possible and freeze below -20° C

Transport Container

Transport tube

Transport Temperature

Frozen

Specimen Stability

Room temperature: Unacceptable
Refrigerated: 7 days
Frozen: 28 days

Setup Schedule

Service Area must be determined

Not offered in Quest Diagnostics Nichols Institute (IFD) – San Juan Capistrano. Please provide SERVICE AREA INFORMATION to find available tests you can order.

In-home collection is not available in your area through Quest Mobile.

Test Details

Clinical Significance

Test Resources

Reference ranges are provided as general guidance only. To interpret test results use the reference range in the laboratory report.

The CPT codes provided are based on AMA guidance and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

This material contains content from LOINC® (http://loinc.org). The LOINC Table, LOINC Table Core are copyright © 1995-2019, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license at http://loinc.org/license.

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